Method for analysis and assessment of the relation between stress and reliability of knowledge-based actions in the probabilistic safety analysis

International Nuclear Information System (INIS)

Fassmann, Werner

2014-06-01

According to the current theoretical and empirical state-of-the-art, stress has to be understood as the emotional and cognitive reaction by which humans adapt to situations which imply real or imagined danger, threat, or frustration of important personal goals or needs. The emotional reaction to such situations can be so extreme that rational coping with the situation will be precluded. In less extreme cases, changes of cognitive processes underlying human action will occur, which may systematically affect the reliability of tasks personnel has to perform in a stressful situation. Reliable task performance by personnel of nuclear power plants and other risk technologies is also affected by such effects. The method developed in the frame of the research and development project RS1198 sponsored by the German Federal Ministry for Economic Affairs and Energy (BMWi) addresses both aspects of emotional and cognitive coping with stressful situations. Analytical and evaluation steps of the approach provide guidance to the end users on how to capture and quantify the contribution of stress-related emotional and cognitive factors to the reliable performance of knowledge-based actions. For this purpose, a suitable guideline has been developed. Further research for clarifying open questions has been identified. A case study application illustrates how to use the method. Part of the work performed in this project was dedicated to a review addressing the question to which extent Swain's approach to the analysis and evaluation of stress is in line with current scientific knowledge. Suitable suggestions for updates have been developed.

Orthopaedic nurses' knowledge and interrater reliability of neurovascular assessments with 2-point discrimination test.

Science.gov (United States)

Turney, Jennifer; Raley Noble, Deana; Kim, Son Chae

2013-01-01

: This study was conducted to evaluate the effects of education on knowledge and interrater reliability of neurovascular assessments with 2-point discrimination (2-PD) test among pediatric orthopaedic nurses. : A pre- and posttest study was done among 60 nurses attending 2-hour educational sessions. Neurovascular assessments with 2-PD test were performed on 64 casted pediatric patients by the nurses and 5 nurse experts before and after the educational sessions. : The mean neurovascular assessment knowledge score was improved at posteducation compared with the preeducation (p < .001). The 2-PD test interrater reliability also improved from Cohen's kappa value of 0.24-0.48 at posteducation. : The 2-hour educational session may be effective in improving nurses' knowledge and the interrater reliability of neurovascular assessment with 2-PD test.

Developing safety performance functions incorporating reliability-based risk measures.

Science.gov (United States)

Ibrahim, Shewkar El-Bassiouni; Sayed, Tarek

2011-11-01

Current geometric design guides provide deterministic standards where the safety margin of the design output is generally unknown and there is little knowledge of the safety implications of deviating from these standards. Several studies have advocated probabilistic geometric design where reliability analysis can be used to account for the uncertainty in the design parameters and to provide a risk measure of the implication of deviation from design standards. However, there is currently no link between measures of design reliability and the quantification of safety using collision frequency. The analysis presented in this paper attempts to bridge this gap by incorporating a reliability-based quantitative risk measure such as the probability of non-compliance (P(nc)) in safety performance functions (SPFs). Establishing this link will allow admitting reliability-based design into traditional benefit-cost analysis and should lead to a wider application of the reliability technique in road design. The present application is concerned with the design of horizontal curves, where the limit state function is defined in terms of the available (supply) and stopping (demand) sight distances. A comprehensive collision and geometric design database of two-lane rural highways is used to investigate the effect of the probability of non-compliance on safety. The reliability analysis was carried out using the First Order Reliability Method (FORM). Two Negative Binomial (NB) SPFs were developed to compare models with and without the reliability-based risk measures. It was found that models incorporating the P(nc) provided a better fit to the data set than the traditional (without risk) NB SPFs for total, injury and fatality (I+F) and property damage only (PDO) collisions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Reliability and consistency of a validated sun exposure questionnaire in a population-based Danish sample.

Science.gov (United States)

Køster, B; Søndergaard, J; Nielsen, J B; Olsen, A; Bentzen, J

2018-06-01

An important feature of questionnaire validation is reliability. To be able to measure a given concept by questionnaire validly, the reliability needs to be high. The objectives of this study were to examine reliability of attitude and knowledge and behavioral consistency of sunburn in a developed questionnaire for monitoring and evaluating population sun-related behavior. Sun related behavior, attitude and knowledge was measured weekly by a questionnaire in the summer of 2013 among 664 Danes. Reliability was tested in a test-retest design. Consistency of behavioral information was tested similarly in a questionnaire adapted to measure behavior throughout the summer. The response rates for questionnaire 1, 2 and 3 were high and the drop out was not dependent on demographic characteristic. There was at least 73% agreement between sunburns in the measurement week and the entire summer, and a possible sunburn underestimation in questionnaires summarizing the entire summer. The participants underestimated their outdoor exposure in the evaluation covering the entire summer as compared to the measurement week. The reliability of scales measuring attitude and knowledge was high for majority of scales, while consistency in protection behavior was low. To our knowledge, this is the first study to report reliability for a completely validated questionnaire on sun-related behavior in a national random population based sample. Further, we show that attitude and knowledge questions confirmed their validity with good reliability, while consistency of protection behavior in general and in a week's measurement was low.

Risk Management of New Microelectronics for NASA: Radiation Knowledge-base

Science.gov (United States)

LaBel, Kenneth A.

2004-01-01

Contents include the following: NASA Missions - implications to reliability and radiation constraints. Approach to Insertion of New Technologies Technology Knowledge-base development. Technology model/tool development and validation. Summary comments.

Reliability and consistency of a validated sun exposure questionnaire in a population-based Danish sample

Directory of Open Access Journals (Sweden)

B. Køster

2018-06-01

Full Text Available An important feature of questionnaire validation is reliability. To be able to measure a given concept by questionnaire validly, the reliability needs to be high.The objectives of this study were to examine reliability of attitude and knowledge and behavioral consistency of sunburn in a developed questionnaire for monitoring and evaluating population sun-related behavior.Sun related behavior, attitude and knowledge was measured weekly by a questionnaire in the summer of 2013 among 664 Danes. Reliability was tested in a test-retest design. Consistency of behavioral information was tested similarly in a questionnaire adapted to measure behavior throughout the summer.The response rates for questionnaire 1, 2 and 3 were high and the drop out was not dependent on demographic characteristic. There was at least 73% agreement between sunburns in the measurement week and the entire summer, and a possible sunburn underestimation in questionnaires summarizing the entire summer. The participants underestimated their outdoor exposure in the evaluation covering the entire summer as compared to the measurement week. The reliability of scales measuring attitude and knowledge was high for majority of scales, while consistency in protection behavior was low.To our knowledge, this is the first study to report reliability for a completely validated questionnaire on sun-related behavior in a national random population based sample. Further, we show that attitude and knowledge questions confirmed their validity with good reliability, while consistency of protection behavior in general and in a week's measurement was low. Keywords: Questionnaire, Validation, Reliability, Skin cancer, Prevention, Ultraviolet radiation

Optimal, Reliability-Based Code Calibration

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2002-01-01

Reliability based code calibration is considered in this paper. It is described how the results of FORM based reliability analysis may be related to the partial safety factors and characteristic values. The code calibration problem is presented in a decision theoretical form and it is discussed how...... of reliability based code calibration of LRFD based design codes....

Development of a tool for knowledge base verification of expert system based on Design/CPN

International Nuclear Information System (INIS)

Kim, Jong Hyun

1998-02-01

Verification is a necessary work in developing a reliable expert system. Verification is a process aimed at demonstrating whether a system meets it's specified requirements. As expert systems are used in various applications, the knowledge base verification of systems takes an important position. The conventional Petri net approach that has been studied recently in order to verify the knowledge base is found that it is inadequate to verify the knowledge base of large and complex system, such as alarm processing system of nuclear power plant. Thus, we propose an improved method that models the knowledge base as enhanced colored Petri net. In this study, we analyze the reachability and the error characteristics of the knowledge base. Generally, verification process requires computational support by automated tools. For this reason, this study developed a tool for knowledge base verification based on Design/CPN, which is a tool for editing, modeling, and simulating Colored Petri net. This tool uses Enhanced Colored Petri net as a modeling method. By applying this tool to the knowledge base of nuclear power plant, it is noticed that it can successfully check most of the anomalies that can occur in a knowledge base

A method of knowledge base verification for nuclear power plant expert systems using extended Petri Nets

International Nuclear Information System (INIS)

Kwon, I. W.; Seong, P. H.

1996-01-01

The adoption of expert systems mainly as operator supporting systems is becoming increasingly popular as the control algorithms of system become more and more sophisticated and complicated. The verification phase of knowledge base is an important part for developing reliable expert systems, especially in nuclear industry. Although several strategies or tools have been developed to perform potential error checking, they often neglect the reliability of verification methods. Because a Petri net provides a uniform mathematical formalization of knowledge base, it has been employed for knowledge base verification. In this work, we devise and suggest an automated tool, called COKEP(Checker of Knowledge base using Extended Petri net), for detecting incorrectness, inconsistency, and incompleteness in a knowledge base. The scope of the verification problem is expended to chained errors, unlike previous studies that assume error incidence to be limited to rule pairs only. In addition, we consider certainty factor in checking, because most of knowledge bases have certainly factors. 8 refs,. 2 figs,. 4 tabs. (author)

Designing the database for a reliability aware Model-Based System Engineering process

International Nuclear Information System (INIS)

Cressent, Robin; David, Pierre; Idasiak, Vincent; Kratz, Frederic

2013-01-01

This article outlines the need for a reliability database to implement model-based description of components failure modes and dysfunctional behaviors. We detail the requirements such a database should honor and describe our own solution: the Dysfunctional Behavior Database (DBD). Through the description of its meta-model, the benefits of integrating the DBD in the system design process is highlighted. The main advantages depicted are the possibility to manage feedback knowledge at various granularity and semantic levels and to ease drastically the interactions between system engineering activities and reliability studies. The compliance of the DBD with other reliability database such as FIDES is presented and illustrated. - Highlights: ► Model-Based System Engineering is more and more used in the industry. ► It results in a need for a reliability database able to deal with model-based description of dysfunctional behavior. ► The Dysfunctional Behavior Database aims to fulfill that need. ► It helps dealing with feedback management thanks to its structured meta-model. ► The DBD can profit from other reliability database such as FIDES.

Reliability-Based Optimization in Structural Engineering

DEFF Research Database (Denmark)

Enevoldsen, I.; Sørensen, John Dalsgaard

1994-01-01

In this paper reliability-based optimization problems in structural engineering are formulated on the basis of the classical decision theory. Several formulations are presented: Reliability-based optimal design of structural systems with component or systems reliability constraints, reliability...

Development of knowledge acquisition methods for knowledge base construction for autonomous plants

Energy Technology Data Exchange (ETDEWEB)

Yoshikawa, S. [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center; Sasajima, M.; Kitamura, Y.; Ikeda, M.; Mizoguchi, R.

1993-03-01

In order to enhance safety and reliability of nuclear plant operation, it is strongly desired to construct diagnostic knowledge base without lacking, contradiction, and description inconsistency. Nowadays, an advanced method Knowledge Compiler` has been studied to acquire diagnostic knowledge, mainly based on qualitative reasoning technique, without accumulating heuristics by interviews. Until now, 2 methods to suppress the ambiguity observed when qualitative reasoning mechanism were applied to heat transport systems of nuclear power plants: In the first method, qualitative values are allocated to the system variables along with the causality direction, avoiding contradictions among plural variables in each qualitative constraint describing knowledge of deviation propagation, heat balance, or energy conservation. In the second method, all the qualitative information is represented as a set of simultaneous qualitative equations. And, an appropriate subset is selected so that the qualitative solutions of unknowns in this subset can be derived independently of the remaining part. A contrary method is applied for the selected subset to derive local solutions. Then the problem size is reduced by substituting solutions of the subset, in a recursive manner. In the previous report on this research project, complete computer softwares have been constructed based on these methods, and applied to a 2-loop heat transport system of a nuclear power plant. The detailed results are discussed in this report. In addition, an integrated configuration of diagnostic knowledge generation system of nuclear power plants is proposed, based upon the results and new foundings obtained through the research activities so far, and the future works to overcome remaining problems are also identified. (author)

Inverse Reliability Task: Artificial Neural Networks and Reliability-Based Optimization Approaches

OpenAIRE

Lehký , David; Slowik , Ondřej; Novák , Drahomír

2014-01-01

Part 7: Genetic Algorithms; International audience; The paper presents two alternative approaches to solve inverse reliability task – to determine the design parameters to achieve desired target reliabilities. The first approach is based on utilization of artificial neural networks and small-sample simulation Latin hypercube sampling. The second approach considers inverse reliability task as reliability-based optimization task using double-loop method and also small-sample simulation. Efficie...

Knowledge collaborative incentive based on inter-organizational cooperative innovation of project-based supply chain

Directory of Open Access Journals (Sweden)

Guangdong Wu

2013-09-01

Full Text Available Purpose: Within project-based supply chain inter-organizational cooperative innovation, the achievement of project value-adding reflects by factors such as project-based organizational effect level, the relationship between project cooperative innovation objectives etc. The purpose is to provide a reliable reference for the contractor reasonably allocate the effect level and resources between the knowledge input and innovation stage and realize the knowledge collaboration for project-based supply chain. Design/methodology/approach: Based on the assumption of equal cooperation between project-based organizations, from the view of maximizing project value-adding and the relationship of effect cost between knowledge input and innovation stage in consideration, the knowledge collaborative incentive model for project-based supply chain inter-organizational cooperative innovation was established, and solved through the first-order and second-order approach, then the digital simulation and example analysis were presented. Findings: The results show that, the project management enterprise resorted to adjust project knowledge collaboration incentive intensity and implemented knowledge input-innovation coordinative incentive strategy, not only could achieve project value-adding maximization, but also could realize net earnings Pareto improvement between project management enterprise and contractor. Research limitations/implications: To simplify the knowledge flow among project-based organizations, the knowledge flow in the model hypothesis is presented as knowledge input and knowledge innovation stage, thus it may affect the final analysis results. Originality/value: In construction project practice, knowledge is become more and more important to achieve project value-adding. The research can provide a theoretical guideline for the project-based organizations, such as the contractor, the owner, especially how to utilize their core knowledge.

Reliability of two social cognition tests: The combined stories test and the social knowledge test.

Science.gov (United States)

Thibaudeau, Élisabeth; Cellard, Caroline; Legendre, Maxime; Villeneuve, Karèle; Achim, Amélie M

2018-04-01

Deficits in social cognition are common in psychiatric disorders. Validated social cognition measures with good psychometric properties are necessary to assess and target social cognitive deficits. Two recent social cognition tests, the Combined Stories Test (COST) and the Social Knowledge Test (SKT), respectively assess theory of mind and social knowledge. Previous studies have shown good psychometric properties for these tests, but the test-retest reliability has never been documented. The aim of this study was to evaluate the test-retest reliability and the inter-rater reliability of the COST and the SKT. The COST and the SKT were administered twice to a group of forty-two healthy adults, with a delay of approximately four weeks between the assessments. Excellent test-retest reliability was observed for the COST, and a good test-retest reliability was observed for the SKT. There was no evidence of practice effect. Furthermore, an excellent inter-rater reliability was observed for both tests. This study shows a good reliability of the COST and the SKT that adds to the good validity previously reported for these two tests. These good psychometrics properties thus support that the COST and the SKT are adequate measures for the assessment of social cognition. Copyright © 2018. Published by Elsevier B.V.

An assessment of maintainability of elevator system to improve facilities management knowledge-base

Science.gov (United States)

Siti, N. A.; Asmone, A. S.; Chew, M. Y. L.

2018-02-01

Elevator system is a highly specialized machinery that requires technicians that have a wider array of knowledge in maintaining the system to be safe and reliable. While attaining reliable data of elevator malfunction become challenges, this study has filled the gap by gathering the management-maintenance issues and operational defects of elevator system. Forty-three types of operation defects were found and the consequence defects and their possible causes of occurrences were discussed. To respond to the prime challenges of maintaining elevator system provided by the industry players’ perspective, a theoretical framework is established as a recommendation to improve knowledge base of defects in elevator system which comprises good practices, and solutions to rectify each defects found. Hence, this research paper has theoretically improved the knowledge base of maintainability of elevator system and provide meaningful guidelines in practical senses to the industry professionals.

Development and Initial Reliability Testing of NAK-50+: A Nutrition Attitude and Knowledge Questionnaire for Adults 50+ Years of Age.

Science.gov (United States)

Ducak, Kate; Keller, Heather

2016-03-01

Few questionnaires to test nutrition knowledge and attitudes of older adults living independently in the community have been developed and tested to assess self-management tools such as Nutri-eSCREEN and other education programs. This study is a first step in the development of a questionnaire designed to evaluate the nutrition knowledge and attitudes of independent older adults (NAK-50+). The steps involved in this study were: (i) drafting initial questions based on the content of the Nutri-eSCREEN education material, (ii) using cognitive interviewing to determine if these questions were understandable and relevant (n = 9 adults ≥50 years of age), and (iii) completing test-retest reliability in a convenient community sample (n = 60 adults ≥50 years of age). Intra-class coefficients (ICC) and kappa were used to determine reliability. A 33-item questionnaire resulted from this development and analysis. ICC for the total score was 0.68 indicating good agreement and thus initial reliability. NAK-50+ is a face valid and reliable questionnaire that assesses nutrition knowledge and attitudes in independent adults aged ≥50 years. Further work to determine construct validity and to refine the questionnaire is warranted. Availability of the questionnaire for this age group will support rigorous evaluation of education and self-management interventions for this segment of the population.

Knowledge base mechanisms

Energy Technology Data Exchange (ETDEWEB)

Suwa, M; Furukawa, K; Makinouchi, A; Mizoguchi, T; Mizoguchi, F; Yamasaki, H

1982-01-01

One of the principal goals of the Fifth Generation Computer System Project for the coming decade is to develop a methodology for building knowledge information processing systems which will provide people with intelligent agents. The key notion of the fifth generation computer system is knowledge used for problem solving. In this paper the authors describe the plan of Randd on knowledge base mechanisms. A knowledge representation system is to be designed to support knowledge acquisition for the knowledge information processing systems. The system will include a knowledge representation language, a knowledge base editor and a debugger. It is also expected to perform as a kind of meta-inference system. In order to develop the large scale knowledge base systems, a knowledge base mechanism based on the relational model is to be studied in the earlier stage of the project. Distributed problem solving is also one of the main issues of the project. 19 references.

Validity and Reliability of Knowledge, Attitude and Behavior Assessment Tool Among Vulnerable Women Concerning Sexually Transmitted Diseases

Directory of Open Access Journals (Sweden)

Zahra Boroumandfar

2016-05-01

Full Text Available Objective: The study aimed to design and evaluate the content and face validity, and reliability of knowledge, attitude, and behavior questionnaire on preventive behaviors among vulnerable women concerning sexually transmitted diseases (STDs.Materials and methods: This cross-sectional study was carried out in two phases of an action research. In the first phase, to explain STDs preventive domains, 20 semi- structured interviews were conducted with the vulnerable women, residing at women prison and women referred to counseling centers. After analyzing content of interviews, three domains were identified: improve their knowledge, modify their attitude and change their behaviors. In the second phase, the questionnaire was designed and tested in a pilot study. Then, its content validity was evaluated. Face validity and reliability of the questionnaire were assessed by test re- test method and Cronbach alpha respectively.Results: Index of content validity in each three domain of the questionnaire (knowledge, attitude and behavior concerning STDs was obtained over 0.6. Overall content validity index was 0.86 in all three domains of the questionnaire. The Cronbach’s alpha as reliability of questionnaire was 0.80 for knowledge, 0.79 for attitude and 0.85 for behavior.Conclusion: The results showed that the designed questionnaire was a valid and reliable tool to measure knowledge, attitude and behavior of vulnerable women, predisposed to risk of STDs.

Software Development for Auto-Generation of Interlocking Knowledge base using Artificial Intelligence Approach

Energy Technology Data Exchange (ETDEWEB)

Ko, Yun Seok [Nanseoul University (Korea); Kim, JOng Sun [Kwangwoon University (Korea)

1999-06-01

This paper proposes IIKBAG (Intelligent Interlocking Knowledge Base Generator) which can build automatically the interlocking knowledge base utilized as the real-time interlocking strategy of the electronic interlocking system in order to enhance it's reliability and expansion. The IIKBAG consists of the inference engine and the knowledge base. The former has an auto-learning function which searches all the train routes for the given station model based on heuristic search technique while dynamically searching the model, and then generates automatically the interlocking patterns obtained from the interlocking relations of signal facilities on the routes. The latter is designed as the structure which the real-time expert system embedded on IS (Interlocking System) can use directly in order to enhances the reliability and accuracy. The IIKBAG is implemented in C computer language for the purpose of the build and interface of the station structure database. And, a typical station model is simulated to prove the validity of the proposed IIKBAG. (author). 13 refs., 5 figs., 2 tabs.

Semantics-based plausible reasoning to extend the knowledge coverage of medical knowledge bases for improved clinical decision support.

Science.gov (United States)

Mohammadhassanzadeh, Hossein; Van Woensel, William; Abidi, Samina Raza; Abidi, Syed Sibte Raza

2017-01-01

Capturing complete medical knowledge is challenging-often due to incomplete patient Electronic Health Records (EHR), but also because of valuable, tacit medical knowledge hidden away in physicians' experiences. To extend the coverage of incomplete medical knowledge-based systems beyond their deductive closure, and thus enhance their decision-support capabilities, we argue that innovative, multi-strategy reasoning approaches should be applied. In particular, plausible reasoning mechanisms apply patterns from human thought processes, such as generalization, similarity and interpolation, based on attributional, hierarchical, and relational knowledge. Plausible reasoning mechanisms include inductive reasoning , which generalizes the commonalities among the data to induce new rules, and analogical reasoning , which is guided by data similarities to infer new facts. By further leveraging rich, biomedical Semantic Web ontologies to represent medical knowledge, both known and tentative, we increase the accuracy and expressivity of plausible reasoning, and cope with issues such as data heterogeneity, inconsistency and interoperability. In this paper, we present a Semantic Web-based, multi-strategy reasoning approach, which integrates deductive and plausible reasoning and exploits Semantic Web technology to solve complex clinical decision support queries. We evaluated our system using a real-world medical dataset of patients with hepatitis, from which we randomly removed different percentages of data (5%, 10%, 15%, and 20%) to reflect scenarios with increasing amounts of incomplete medical knowledge. To increase the reliability of the results, we generated 5 independent datasets for each percentage of missing values, which resulted in 20 experimental datasets (in addition to the original dataset). The results show that plausibly inferred knowledge extends the coverage of the knowledge base by, on average, 2%, 7%, 12%, and 16% for datasets with, respectively, 5%, 10%, 15

Reliability-based optimization of engineering structures

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2008-01-01

The theoretical basis for reliability-based structural optimization within the framework of Bayesian statistical decision theory is briefly described. Reliability-based cost benefit problems are formulated and exemplitied with structural optimization. The basic reliability-based optimization...... problems are generalized to the following extensions: interactive optimization, inspection and repair costs, systematic reconstruction, re-assessment of existing structures. Illustrative examples are presented including a simple introductory example, a decision problem related to bridge re...

Validity and reliability of a questionnaire on knowledge of cardiovascular risk factors for use in Brazil

Directory of Open Access Journals (Sweden)

Marco Aurelio Lumertz Saffi

2013-10-01

Full Text Available Using a sample of patients with coronary artery disease, this methodological study aimed to conduct a cross-cultural adaptation and validation of a questionnaire on knowledge of cardiovascular risk factors (Q-FARCS, lifestyle changes, and treatment adherence for use in Brazil. The questionnaire has three scales: general knowledge of risk factors (RFs; specific knowledge of these RFs; and lifestyle changes achieved. Cross-cultural adaptation included translation, synthesis, back-translation, expert committee review, and pretesting. Face and content validity, reliability, and construct validity were measured. Cronbach’s alpha for the total sample (n = 240 was 0.75. Assessment of psychometric properties revealed adequate face and content validity, and the construct revealed seven components. It was concluded that the Brazilian version of Q-FARCS had adequate reliability and validity for the assessment of knowledge of cardiovascular RFs.

Study on reliability analysis based on multilevel flow models and fault tree method

International Nuclear Information System (INIS)

Chen Qiang; Yang Ming

2014-01-01

Multilevel flow models (MFM) and fault tree method describe the system knowledge in different forms, so the two methods express an equivalent logic of the system reliability under the same boundary conditions and assumptions. Based on this and combined with the characteristics of MFM, a method mapping MFM to fault tree was put forward, thus providing a way to establish fault tree rapidly and realizing qualitative reliability analysis based on MFM. Taking the safety injection system of pressurized water reactor nuclear power plant as an example, its MFM was established and its reliability was analyzed qualitatively. The analysis result shows that the logic of mapping MFM to fault tree is correct. The MFM is easily understood, created and modified. Compared with the traditional fault tree analysis, the workload is greatly reduced and the modeling time is saved. (authors)

An AHP-Based Weighted Analysis of Network Knowledge Management Platforms for Elementary School Students

Science.gov (United States)

Lee, Chung-Ping; Lou, Shi-Jer; Shih, Ru-Chu; Tseng, Kuo-Hung

2011-01-01

This study uses the analytical hierarchy process (AHP) to quantify important knowledge management behaviors and to analyze the weight scores of elementary school students' behaviors in knowledge transfer, sharing, and creation. Based on the analysis of Expert Choice and tests for validity and reliability, this study identified the weight scores of…

Validity and reliability of the Turkish version of the pressure ulcer prevention knowledge assessment instrument.

Science.gov (United States)

Tulek, Zeliha; Polat, Cansu; Ozkan, Ilknur; Theofanidis, Dimitris; Togrol, Rifat Erdem

2016-11-01

Sound knowledge of pressure ulcers is important to enable good prevention. There are limited instruments assessing pressure ulcer knowledge. The Pressure Ulcer Prevention Knowledge Assessment Instrument is among the scales of which psychometric properties have been studied rigorously and reflects the latest evidence. This study aimed to evaluate the validity and reliability of the Turkish version of the Pressure Ulcer Prevention Knowledge Assessment Instrument (PUPKAI-T), an instrument that assesses knowledge of pressure ulcer prevention by using multiple-choice questions. Linguistic validity was verified through front-to-back translation. Psychometric properties of the instrument were studied on a sample of 150 nurses working in a tertiary hospital in Istanbul, Turkey. The content validity index of the translated instrument was 0.94, intra-class correlation coefficients were between 0.37 and 0.80, item difficulty indices were between 0.21 and 0.88, discrimination indices were 0.20-0.78, and the Kuder Richardson for the internal consistency was 0.803. The PUPKAI-T was found to be a valid and reliable tool to evaluate nurses' knowledge on pressure ulcer prevention. The PUPKAI-T may be a useful tool for determining educational needs of nurses on pressure ulcer prevention. Copyright © 2016 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

[Knowledge of university students in Szeged, Hungary about reliable contraceptive methods and sexually transmitted diseases].

Science.gov (United States)

Devosa, Iván; Kozinszky, Zoltán; Vanya, Melinda; Szili, Károly; Fáyné Dombi, Alice; Barabás, Katalin

2016-04-03

Promiscuity and lack of use of reliable contraceptive methods increase the probability of sexually transmitted diseases and the risk of unwanted pregnancies, which are quite common among university students. The aim of the study was to assess the knowledge of university students about reliable contraceptive methods and sexually transmitted diseases, and to assess the effectiveness of the sexual health education in secondary schools, with specific focus on the education held by peers. An anonymous, self-administered questionnaire survey was carried out in a randomized sample of students at the University of Szeged (n = 472, 298 women and 174 men, average age 21 years) between 2009 and 2011. 62.1% of the respondents declared that reproductive health education lessons in high schools held by peers were reliable and authentic source of information, 12.3% considered as a less reliable source, and 25.6% defined the school health education as irrelevant source. Among those, who considered the health education held by peers as a reliable source, there were significantly more females (69.3% vs. 46.6%, p = 0.001), significantly fewer lived in cities (83.6% vs. 94.8%, p = 0.025), and significantly more responders knew that Candida infection can be transmitted through sexual intercourse (79.5% versus 63.9%, p = 0.02) as compared to those who did not consider health education held by peers as a reliable source. The majority of respondents obtained knowledge about sexual issues from the mass media. Young people who considered health educating programs reliable were significantly better informed about Candida disease.

Application of knowledge based software to industrial automation in Japan

International Nuclear Information System (INIS)

Matsumoto, Yoshihiro

1985-01-01

In Japan, large industrial undertakings such as electric utilities or steel works are making first steps towards knowledge engineering, testing the applicability of knowledge based software to industrial automation. The goal is to achieve more intelligent, computer-aided assistance for the personnel and thus to enhance safety, reliability, and maintenance efficiency in large industrial plants. The article presents various examples showing advantages and draw-backs of such systems, and potential applications among others in nuclear or fossil fueled power plants or in electricity supply control systems. (orig./HP) [de

SIIA: a knowledge-based assistant for the SAFT ultrasonic inspection system(a)

International Nuclear Information System (INIS)

Melton, R.B.; Doctor, S.R.; Taylor, T.T.; Badalamente, R.V.

1987-01-01

SIIA(b) is a knowledge-based system designed to assist in making the operation of the Synthetic Aperture Focussing Technique (SAFT) Ultrasonic Inspection System more reliable and efficient. This paper reports on their effort to develop a prototype version of SIIA to demonstrate the feasibility of using knowledge-based systems in nondestructive evaluation (NDE). The first section of the paper describes the structure of the problem and their conceptual design of the knowledge-based system. The next section describes the current state of the prototype SIIA system and relates some of their experiences in developing the system. The final section discusses their plans for future development of SIIA and the implications of this type of system for other NDE techniques and applications

Reliability analysis of software based safety functions

International Nuclear Information System (INIS)

Pulkkinen, U.

1993-05-01

The methods applicable in the reliability analysis of software based safety functions are described in the report. Although the safety functions also include other components, the main emphasis in the report is on the reliability analysis of software. The check list type qualitative reliability analysis methods, such as failure mode and effects analysis (FMEA), are described, as well as the software fault tree analysis. The safety analysis based on the Petri nets is discussed. The most essential concepts and models of quantitative software reliability analysis are described. The most common software metrics and their combined use with software reliability models are discussed. The application of software reliability models in PSA is evaluated; it is observed that the recent software reliability models do not produce the estimates needed in PSA directly. As a result from the study some recommendations and conclusions are drawn. The need of formal methods in the analysis and development of software based systems, the applicability of qualitative reliability engineering methods in connection to PSA and the need to make more precise the requirements for software based systems and their analyses in the regulatory guides should be mentioned. (orig.). (46 refs., 13 figs., 1 tab.)

Reliability-based design of wind turbine blades

DEFF Research Database (Denmark)

Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

2011-01-01

Reliability-based design of wind turbine blades requires identification of the important failure modes/limit states along with stochastic models for the uncertainties and methods for estimating the reliability. In the present paper it is described how reliability-based design can be applied to wi...

A knowledge-based approach to the design of integrated renewable energy systems

Energy Technology Data Exchange (ETDEWEB)

Ramakumar, R.; Abouzahr, I. (Oklahoma State Univ., Stillwater, OK (United States). Engineering Energy Lab.); Ashenayi, K. (Dept. of Electrical Engineering, Univ. of Tulsa, Tulsa, OK (United States))

1992-12-01

Integrated Renewable Energy Systems (IRES) utilize two or more renewable energy resources and end-use technologies to supply a variety of energy needs, often in a stand-alone mode. A knowledge-based design approach that minimizes the total capital cost at a pre-selected reliability level is presented. The reliability level is quantified by the loss of power supply probability (LPSP). The procedure includes some resource-need matching based on economics, the quality of energy needed, and the characteristics of the resource. A detailed example is presented in this paper and discussed to illustrate the usefullness of the design approach.

Role of Knowledge Based Communities in Knowledge Process

Directory of Open Access Journals (Sweden)

Sebastian Ion CEPTUREANU

2015-12-01

Full Text Available In the new economy, knowledge is an essential component of economic and social systems. The organizational focus has to be on building knowledge-based management, development of human resource and building intellectual capital capabilities. Knowledge-based management is defined, at company level, by economic processes that emphasize creation, selling, buying, learning, storing, developing, sharing and protection of knowledge as a decisive condition for profit and long-term sustainability of the company. Hence, knowledge is, concurently, according to a majoritiy of specialists, raw material, capital, product and an essential input. Knowledge-based communities are one of the main constituent elements of a framework for knowledge based management. These are peer networks consisting of practitioners within an organization, supporting each other to perform better through the exchange and sharing of knowledge. Some large companies have contributed or supported the establishment of numerous communities of practice, some of which may have several thousand members. They operate in different ways, are of different sizes, have different areas of interest and addresses knowledge at different levels of its maturity. This article examines the role of knowledge-based communities from the perspective of knowledge based management, given that the arrangements for organizational learning, creating, sharing, use of knowledge within organizations become more heterogeneous and take forms more difficult to predict by managers and specialists.

Development of web-based reliability data base platform

International Nuclear Information System (INIS)

Hwang, Seok Won; Lee, Chang Ju; Sung, Key Yong

2004-01-01

Probabilistic safety assessment (PSA) is a systematic technique which estimates the degree of risk impacts to the public due to an accident scenario. Estimating the occurrence frequencies and consequences of potential scenarios requires a thorough analysis of the accident details and all fundamental parameters. The robustness of PSA to check weaknesses in a design and operation will allow a better informed and balanced decision to be reached. The fundamental parameters for PSA, such as the component failure rates, should be estimated under the condition of steady collection of the evidence throughout the operational period. However, since any single plant data does not sufficiently enough to provide an adequate PSA result, in actual, the whole operating data was commonly used to estimate the reliability parameters for the same type of components. The reliability data of any component type consists of two categories; the generic that is based on the operating experiences of whole plants, and the plant-specific that is based on the operation of a specific plant of interest. The generic data is highly essential for new or recently-built nuclear power plants (NPPs). Generally, the reliability data base may be categorized into the component reliability, initiating event frequencies, human performance, and so on. Among these data, the component reliability seems a key element because it has the most abundant population. Therefore, the component reliability data is essential for taking a part in the quantification of accident sequences because it becomes an input of various basic events which consists of the fault tree

KNOWLEDGE SOCIETY, GENERAL FRAMEWORK FOR KNOWLEDGE BASED ECONOMY

Directory of Open Access Journals (Sweden)

Dragos CRISTEA

2011-03-01

Full Text Available This paper tries to present the existent relation between knowledge society and knowledge based economy. We will identify the main pillars of knowledge society and present their importance for the development of knowledge societies. Further, we will present two perspectives over knowledge societies, respectively science and learning perspectives, that directly affects knowledge based economies. At the end, we will conclude by identifying some important questions that must be answered regarding this new social paradigm.

Knowledge-based utility

International Nuclear Information System (INIS)

Chwalowski, M.

1997-01-01

This presentation provides industry examples of successful marketing practices by companies facing deregulation and competition. The common thread through the examples is that long term survival of today's utility structure is dependent on the strategic role of knowledge. As opposed to regulated monopolies which usually own huge physical assets and have very little intelligence about their customers, unregulated enterprises tend to be knowledge-based, characterized by higher market value than book value. A knowledge-based enterprise gathers data, creates information and develops knowledge by leveraging it as a competitive weapon. It institutionalizes human knowledge as a corporate asset for use over and over again by the use of databases, computer networks, patents, billing, collection and customer services (BCCS), branded interfaces and management capabilities. Activities to become knowledge-based such as replacing inventory/fixed assets with information about material usage to reduce expenditure and achieve more efficient operations, and by focusing on integration and value-adding delivery capabilities, were reviewed

Validity and Reliability of Asbestos Knowledge and Awareness Questionnaire for Environmental Asbestos Exposure in Rural Areas

Directory of Open Access Journals (Sweden)

Selma Metintaş

2017-04-01

Full Text Available Objective: There is no treatment for asbestos–related diseases, but they can be prevented. One of the first interventions is to improve the knowledge level of people in order to protect people from asbestos and asbestos–related diseases. The present study was conducted to develop a questionnaire for measuring the knowledge and awareness level of asbestos and also assess its validity and reliability in a rural population that is exposed to asbestos environmentally. Methods: A questionnaire, interviewer–administered, that included 37 items was employed on a convenient sample consisting of adult persons who attended a tertiary teaching hospital in Eskişehir where asbestos exposure is widespread in its rural areas. After assessment of validity and reliability of the results, the questionnaire was refined to 19 items and one subscale. Results: A total of 760 participants were included in this study. The mean age of participants was 53.2±15.1 years and 51.6% of them were male. The discrimination and difficulty indices of the asbestos knowledge and awareness questionnaire ranged between 20.0–60.5% and 0.39–0.98, respectively. Cronbach’s alpha coefficient was 0.951 for overall items. The median (min–max and mean (SD score of the study population were 30 (19–56 and 33.9 (11.9, respectively. The score increased correspondingly with greater knowledge levels. Conclusion: This questionnaire is a practical and easy tool to apply with acceptable reliability and validity on high-risk adults in rural areas with environmental asbestos exposure.

[Evaluation on the validity and reliability of the Diabetes Self-management Knowledge, Attitude, and Behavior Assessment Scale (DSKAB)].

Science.gov (United States)

Liu, Xiaoli; Dai, Long; Chen, Bo; Feng, Nongping; Wu, Qianhui; Lin, Yonghai; Zhang, Lan; Tan, Dong; Zhang, Jinhua; Tu, Huijuan; Li, Changfeng; Wang, Wenjuan

2016-01-01

To evaluate the validity and reliability of Diabetes Self-management Knowledge, Attitude, and Behavior Assessment Scale (DSKAB). We selected 460 patients with diabetes in the community, used the scale which was after two rounds of the Delphi method and pilot study. Investigators surveyed the patients by the way of face to face. by draw lots, we selected 25 community diabetes randomly for repeating investigations after one week. The validity analyses included face validity, content validity, construct validity and discriminant validity. The reliability analyses included Cronbach's α coefficient, θ coefficient, Ω coefficient, split-half reliability and test-retest reliability. This study distributed a total of 460 questionnaires, reclaimed 442, qualified 432. The score of the scale was 254.59 ± 28.90, the scores of the knowledge, attitude, behavior sub-scales were 82.44 ± 11.24, 63.53 ± 5.77 and 108.61 ± 17.55, respectively. It had excellent face validity and content validity. The correlation coefficient was from 0.71 to 0.91 among three sub-scales and the scale, Pvalidity. The scores of high group and low group in three sub-scales were: knowledge (91.12 ± 3.62) and (69.96 ± 11.20), attitude (68.75 ± 4.51) and (58.79 ± 4.87), behavior (129.38 ± 8.53) and (89.65 ± 11.34),mean scores of three sub-scales were apparently different, which compared between high score group and low score group, the t value were - 19.45, -16.24 and -30.29, respectively, Pvalidity. The Cronbach's α coefficient of the scale and three sub-scales was from 0.79 to 0.93, the θ coefficient was from 0.86 to 0.95, the Ω coefficient was from 0.90 to 0.98, split-half reliability was from 0.89 to 0.95.Test-retest reliability of the scale was 0.51;the three sub-scales was from 0.46 to 0.52, Pvalidity and reliability of the Diabetes Self-management Knowledge, Attitude, and Behavior Assessment Scale are excellent, which is a suitable instrument to evaluate the self-management for patients

The knowledge base of journalism

DEFF Research Database (Denmark)

Svith, Flemming

In this paper I propose the knowledge base as a fruitful way to apprehend journalism. With the claim that the majority of practice is anchored in knowledge – understood as 9 categories of rationales, forms and levels – this knowledge base appears as a contextual look at journalists’ knowledge......, and place. As an analytical framework, the knowledge base is limited to understand the practice of newspaper journalists, but, conversely, the knowledge base encompasses more general beginnings through the inclusion of overall structural relationships in the media and journalism and general theories...... on practice and knowledge. As the result of an abductive reasoning is a theory proposal, there is a need for more deductive approaches to test the validity of this knowledge base claim. It is thus relevant to investigate which rationales are included in the knowledge base of journalism, as the dimension does...

The analysis phase in development of knowledge-based systems

International Nuclear Information System (INIS)

Brooking, A.G.

1986-01-01

Over the past twenty years computer scientists have realized that, in order to produce reliable software that is easily modifiable, a proven methodology is required. Unlike conventional systems there is little knowledge of the life cycle of these knowledge-based systems. However, if the life cycle of conventional systems, it is not unreasonable to assume that analysis will come first. With respect to the analysis task there is an enormous difference in types of analysis. Conventional systems analysis is predominately concerned with what happens within the system. Typically, procedures will be noted in the way they relate to each other, the way data moves and changes within the system. There is often an example, on paper or machine, that can be observed

Reliability Based Optimization of Structural Systems

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

1987-01-01

The optimization problem to design structural systems such that the reliability is satisfactory during the whole lifetime of the structure is considered in this paper. Some of the quantities modelling the loads and the strength of the structure are modelled as random variables. The reliability...... is estimated using first. order reliability methods ( FORM ). The design problem is formulated as the optimization problem to minimize a given cost function such that the reliability of the single elements satisfies given requirements or such that the systems reliability satisfies a given requirement....... For these optimization problems it is described how a sensitivity analysis can be performed. Next, new optimization procedures to solve the optimization problems are presented. Two of these procedures solve the system reliability based optimization problem sequentially using quasi-analytical derivatives. Finally...

The Development of the IMIA Knowledge Base

Directory of Open Access Journals (Sweden)

Graham Wright

2011-10-01

Objectives: The aim of the project was to explore the theoretical constructs underpinning the discipline of health informatics and produce a cognitive map of the existing understanding of the discipline and develop the knowledge base of health informatics for the IMIA and the BCS. Method: The five-phase project, described in this article, undertaken to define the discipline of health informatics used four forms of triangulation. Results: The output from the project is a framework giving the 14 major headings (Subjects and 245 elements, which together describe the current perception of the discipline of health informatics. Conclusion: This article describes how each phase of the project was strengthened, through using triangulation within and between the different phases. This was done to ensure that the investigators could be confident in the confirmation and completeness of data, and assured of the validity and reliability of the final output of the ‘IMIA Knowledge Base’ that was endorsed by the IMIA Board in November 2009.

Knowledge Acquisition Using Linguistic-Based Knowledge Analysis

Science.gov (United States)

Daniel L. Schmoldt

1998-01-01

Most knowledge-based system developmentefforts include acquiring knowledge from one or more sources. difficulties associated with this knowledge acquisition task are readily acknowledged by most researchers. While a variety of knowledge acquisition methods have been reported, little has been done to organize those different methods and to suggest how to apply them...

Designing the central knowledge base for the purposes of final works in architecture

Directory of Open Access Journals (Sweden)

Aleksić Ljiljana

2014-01-01

Full Text Available The solution for many issues related to the selection of construction products, currently present on the market, could be a Central knowledge base, consisting of verified and reliable data of construction products. Beside previous participants: investor, architect and contractor, that were involved in the processes of design and construction, herein is equally introduced manufacturer construction materials and products. The Central knowledge base consists of: a catalog sheets of the graphics base, alphanumeric base and base with textual data, and represents a flexible system that is subject to amendments. It is built to support architects during processes design and construction, as well as for education of students attending subject Final works at the Faculty of Civil Engineering in Subotica.

Foundation: Transforming data bases into knowledge bases

Science.gov (United States)

Purves, R. B.; Carnes, James R.; Cutts, Dannie E.

1987-01-01

One approach to transforming information stored in relational data bases into knowledge based representations and back again is described. This system, called Foundation, allows knowledge bases to take advantage of vast amounts of pre-existing data. A benefit of this approach is inspection, and even population, of data bases through an intelligent knowledge-based front-end.

Knowledge Representation and Inference for Analysis and Design of Database and Tabular Rule-Based Systems

Directory of Open Access Journals (Sweden)

Antoni Ligeza

2001-01-01

Full Text Available Rulebased systems constitute a powerful tool for specification of knowledge in design and implementation of knowledge based systems. They provide also a universal programming paradigm for domains such as intelligent control, decision support, situation classification and operational knowledge encoding. In order to assure safe and reliable performance, such system should satisfy certain formal requirements, including completeness and consistency. This paper addresses the issue of analysis and verification of selected properties of a class of such system in a systematic way. A uniform, tabular scheme of single-level rule-based systems is considered. Such systems can be applied as a generalized form of databases for specification of data pattern (unconditional knowledge, or can be used for defining attributive decision tables (conditional knowledge in form of rules. They can also serve as lower-level components of a hierarchical multi-level control and decision support knowledge-based systems. An algebraic knowledge representation paradigm using extended tabular representation, similar to relational database tables is presented and algebraic bases for system analysis, verification and design support are outlined.

Reliability Assessment of Cloud Computing Platform Based on Semiquantitative Information and Evidential Reasoning

Directory of Open Access Journals (Sweden)

Hang Wei

2016-01-01

Full Text Available A reliability assessment method based on evidential reasoning (ER rule and semiquantitative information is proposed in this paper, where a new reliability assessment architecture including four aspects with both quantitative data and qualitative knowledge is established. The assessment architecture is more objective in describing complex dynamic cloud computing environment than that in traditional method. In addition, the ER rule which has good performance for multiple attribute decision making problem is employed to integrate different types of the attributes in assessment architecture, which can obtain more accurate assessment results. The assessment results of the case study in an actual cloud computing platform verify the effectiveness and the advantage of the proposed method.

One knowledge base or many knowledge pools?

DEFF Research Database (Denmark)

Lundvall, Bengt-Åke

It is increasingly realized that knowledge is the most important resource and that learning is the most important process in the economy. Sometimes this is expressed by coining the current era as characterised by a ‘knowledge based economy'. But this concept might be misleading by indicating...... that there is one common knowledge base on which economic activities can be built. In this paper we argue that it is more appropriate to see the economy as connecting to different ‘pools of knowledge'. The argument is built upon a conceptual framework where we make distinctions between private/public, local....../global, individual/collective and tacit/codified knowledge. The purpose is both ‘academic' and practical. Our analysis demonstrates the limits of a narrowly economic perspective on knowledge and we show that these distinctions have important implications both for innovation policy and for management of innovation....

Knowledge-Based Systems for the Assessment and Management of Bridge Structures

DEFF Research Database (Denmark)

Miyamoto, A.; Thoft-Christensen, Palle; Yan, B.

2004-01-01

. The aim of this paper is to summarize the finding of up-to-date research articles concerning the application of knowledge-based systems to assessment and management of structures and to illustrate the potential of such systems in the structural engineering. Two modern bridge management systems (BMS......It is becoming an important social problem to make maintenance and rehabilitation of existing infrastructures such as bridges, buildings, etc. The kernel of such structure management is to develop a method of safety assessment on items which include remaining life and load carrying capacity......'s) are presented in the paper. The first is a BMS to assess the performance and derive optimal strategies for inspection and maintenance of concrete structures using reliability based and knowledge based systems. The second is the concrete bridge rating expert system (BREX) to evaluate the performance of existing...

Knowledge representation and knowledge base design for operator advisor system

International Nuclear Information System (INIS)

Hangos, K.M.; Sziano, T.; Tapolcai, L.

1990-01-01

The problems of knowledge representation, knowledge base handling and design has been described for an Operator Advisor System in the Paks Nuclear Power Plant. The Operator Advisor System is to be implemented as a part of the 5th and 6th unit. The knowledge of the Operator Advisor system is described by a few elementary knowledge items (diagnostic event functions, fault graph, action trees), weighted directed graphs have been found as their common structure. List-type and relational representation of these graphs have been used for the on-line and off-line part of the knowledge base respectively. A uniform data base design and handling has been proposed which consists of a design system, a knowledge base editor and a knowledge base compiler

On Bayesian System Reliability Analysis

Energy Technology Data Exchange (ETDEWEB)

Soerensen Ringi, M

1995-05-01

The view taken in this thesis is that reliability, the probability that a system will perform a required function for a stated period of time, depends on a person`s state of knowledge. Reliability changes as this state of knowledge changes, i.e. when new relevant information becomes available. Most existing models for system reliability prediction are developed in a classical framework of probability theory and they overlook some information that is always present. Probability is just an analytical tool to handle uncertainty, based on judgement and subjective opinions. It is argued that the Bayesian approach gives a much more comprehensive understanding of the foundations of probability than the so called frequentistic school. A new model for system reliability prediction is given in two papers. The model encloses the fact that component failures are dependent because of a shared operational environment. The suggested model also naturally permits learning from failure data of similar components in non identical environments. 85 refs.

On Bayesian System Reliability Analysis

International Nuclear Information System (INIS)

Soerensen Ringi, M.

1995-01-01

The view taken in this thesis is that reliability, the probability that a system will perform a required function for a stated period of time, depends on a person's state of knowledge. Reliability changes as this state of knowledge changes, i.e. when new relevant information becomes available. Most existing models for system reliability prediction are developed in a classical framework of probability theory and they overlook some information that is always present. Probability is just an analytical tool to handle uncertainty, based on judgement and subjective opinions. It is argued that the Bayesian approach gives a much more comprehensive understanding of the foundations of probability than the so called frequentistic school. A new model for system reliability prediction is given in two papers. The model encloses the fact that component failures are dependent because of a shared operational environment. The suggested model also naturally permits learning from failure data of similar components in non identical environments. 85 refs

Knowledge-based machine indexing from natural language text: Knowledge base design, development, and maintenance

Science.gov (United States)

Genuardi, Michael T.

1993-01-01

One strategy for machine-aided indexing (MAI) is to provide a concept-level analysis of the textual elements of documents or document abstracts. In such systems, natural-language phrases are analyzed in order to identify and classify concepts related to a particular subject domain. The overall performance of these MAI systems is largely dependent on the quality and comprehensiveness of their knowledge bases. These knowledge bases function to (1) define the relations between a controlled indexing vocabulary and natural language expressions; (2) provide a simple mechanism for disambiguation and the determination of relevancy; and (3) allow the extension of concept-hierarchical structure to all elements of the knowledge file. After a brief description of the NASA Machine-Aided Indexing system, concerns related to the development and maintenance of MAI knowledge bases are discussed. Particular emphasis is given to statistically-based text analysis tools designed to aid the knowledge base developer. One such tool, the Knowledge Base Building (KBB) program, presents the domain expert with a well-filtered list of synonyms and conceptually-related phrases for each thesaurus concept. Another tool, the Knowledge Base Maintenance (KBM) program, functions to identify areas of the knowledge base affected by changes in the conceptual domain (for example, the addition of a new thesaurus term). An alternate use of the KBM as an aid in thesaurus construction is also discussed.

[Reliability of nursing outcomes classification label "Knowledge: cardiac disease management (1830)" in outpatients with heart failure].

Science.gov (United States)

Cañón-Montañez, Wilson; Oróstegui-Arenas, Myriam

2015-01-01

To determine the reliability (internal consistency, inter-rater reproducibility and level of agreement) of nursing outcome: "Knowledge: cardiac disease management (1830)" of the version published in Spanish, in outpatients with heart failure. A reliability study was conducted on 116 outpatients with heart failure. Six indicators of nursing outcome were operationalized. All participants were assessed simultaneously by two evaluators. Three evaluation periods were defined: initial (at baseline), final (a month later), and follow-up (two months later). Internal consistency by Cronbach alpha coefficient, inter-rater reproducibility with intraclass correlation coefficient of reproducibility or agreement and level agreement using the 95% limits of Bland and Altman. Cronbach's alpha was 0.83 (95% CI: 0.77 - 0.89) in the final evaluation, and follow-up values of 0.85 (95% CI: 0.82-0.89) and 0.83 (95% CI: 0.78 - 0.88) were found for the first and second evaluator, respectively. The intraclass correlation coefficient showed values greater 0.9 in the three evaluation periods in both the random and mixed model. The Bland-Altman 95% limits of agreement were close to zero in the three evaluations performed. The questionnaire operationalized to assess the nursing outcome: "Knowledge: cardiac disease management (1830)" in its Spanish version, is a reliable method to measure skills and knowledge in outpatients with heart failure in the Colombian context. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Awareness, knowledge, and attitude of dentistry students in Kerman towards evidence-based dentistry

Science.gov (United States)

Sarani, Arezoo; Sarani, Melika; Abdar, Mohammad Esmaeli; Abdar, Zahra Esmaeili

2016-01-01

Introduction Evidence-based care helps dentists provide quality dental services to patients, and such care is based on the use of reliable information about treatment and patient care from a large number of papers, books, and published textbooks. This study aimed to determine the knowledge, awareness, and attitude of dentistry students towards evidence-based dentistry. Methods In this cross-sectional study, all dentistry students who were studying in their sixth semester and higher in the Kerman School of Dentistry (n = 73) were studied. The data were analyzed using SPSS version 17 and the independent-samples t-tests and the ANOVA test. Results The means of the students’ knowledge, awareness, and attitude scores were 29.2 ± 10.8, 29.9 ± 8.12 and 44.5 ± 5.3, respectively. Among demographic variables, only the number of semesters showed a significant difference with knowledge, awareness, and attitude of dentistry students toward evidence-based dentistry (p = 0.001). Conclusion According to the results of this study, knowledge and awareness of dentistry students at Kerman University of Medical Sciences towards evidence-based dentistry were average and have a neutral attitude. Thus, providing necessary training in this regard will cause promoting the knowledge, awareness, and improved attitudes of dentistry students. PMID:27382446

Fuzzy knowledge bases integration based on ontology

OpenAIRE

Ternovoy, Maksym; Shtogrina, Olena

2012-01-01

the paper describes the approach for fuzzy knowledge bases integration with the usage of ontology. This approach is based on metadata-base usage for integration of different knowledge bases with common ontology. The design process of metadata-base is described.

Dynamic reliability of digital-based transmitters

Energy Technology Data Exchange (ETDEWEB)

Brissaud, Florent, E-mail: florent.brissaud.2007@utt.f [Institut National de l' Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France) and Universite de Technologie de Troyes - UTT, Institut Charles Delaunay - ICD and UMR CNRS 6279 STMR, 12 rue Marie Curie, BP 2060, 10010 Troyes Cedex (France); Smidts, Carol [Ohio State University (OSU), Nuclear Engineering Program, Department of Mechanical Engineering, Scott Laboratory, 201 W 19th Ave, Columbus OH 43210 (United States); Barros, Anne; Berenguer, Christophe [Universite de Technologie de Troyes (UTT), Institut Charles Delaunay (ICD) and UMR CNRS 6279 STMR, 12 rue Marie Curie, BP 2060, 10010 Troyes Cedex (France)

2011-07-15

Dynamic reliability explicitly handles the interactions between the stochastic behaviour of system components and the deterministic behaviour of process variables. While dynamic reliability provides a more efficient and realistic way to perform probabilistic risk assessment than 'static' approaches, its industrial level applications are still limited. Factors contributing to this situation are the inherent complexity of the theory and the lack of a generic platform. More recently the increased use of digital-based systems has also introduced additional modelling challenges related to specific interactions between system components. Typical examples are the 'intelligent transmitters' which are able to exchange information, and to perform internal data processing and advanced functionalities. To make a contribution to solving these challenges, the mathematical framework of dynamic reliability is extended to handle the data and information which are processed and exchanged between systems components. Stochastic deviations that may affect system properties are also introduced to enhance the modelling of failures. A formalized Petri net approach is then presented to perform the corresponding reliability analyses using numerical methods. Following this formalism, a versatile model for the dynamic reliability modelling of digital-based transmitters is proposed. Finally the framework's flexibility and effectiveness is demonstrated on a substantial case study involving a simplified model of a nuclear fast reactor.

Knowledge-based Telecom Industry

OpenAIRE

Vinje, Villeman; Nordkvelde, Marius

2011-01-01

BI Norwegian School of Management is conducting a national research project entitled “A knowledge-based Norway”. Thirteen major knowledge-based industries in Norway are being analyzed under the auspices of the project. This study assesses the underlying properties of a global knowledge hub to examine the extent to which the Norwegian telecom industry – which encompasses all telecom firms located in Norway regardless of ownership – constitutes a global knowledge hub. It commences with a ge...

Reliability-based sensitivity of mechanical components with arbitrary distribution parameters

International Nuclear Information System (INIS)

Zhang, Yi Min; Yang, Zhou; Wen, Bang Chun; He, Xiang Dong; Liu, Qiaoling

2010-01-01

This paper presents a reliability-based sensitivity method for mechanical components with arbitrary distribution parameters. Techniques from the perturbation method, the Edgeworth series, the reliability-based design theory, and the sensitivity analysis approach were employed directly to calculate the reliability-based sensitivity of mechanical components on the condition that the first four moments of the original random variables are known. The reliability-based sensitivity information of the mechanical components can be accurately and quickly obtained using a practical computer program. The effects of the design parameters on the reliability of mechanical components were studied. The method presented in this paper provides the theoretic basis for the reliability-based design of mechanical components

Structural hybrid reliability index and its convergent solving method based on random–fuzzy–interval reliability model

Directory of Open Access Journals (Sweden)

Hai An

2016-08-01

Full Text Available Aiming to resolve the problems of a variety of uncertainty variables that coexist in the engineering structure reliability analysis, a new hybrid reliability index to evaluate structural hybrid reliability, based on the random–fuzzy–interval model, is proposed in this article. The convergent solving method is also presented. First, the truncated probability reliability model, the fuzzy random reliability model, and the non-probabilistic interval reliability model are introduced. Then, the new hybrid reliability index definition is presented based on the random–fuzzy–interval model. Furthermore, the calculation flowchart of the hybrid reliability index is presented and it is solved using the modified limit-step length iterative algorithm, which ensures convergence. And the validity of convergent algorithm for the hybrid reliability model is verified through the calculation examples in literature. In the end, a numerical example is demonstrated to show that the hybrid reliability index is applicable for the wear reliability assessment of mechanisms, where truncated random variables, fuzzy random variables, and interval variables coexist. The demonstration also shows the good convergence of the iterative algorithm proposed in this article.

IAEA's experience in compiling a generic component reliability data base

International Nuclear Information System (INIS)

Tomic, B.; Lederman, L.

1988-01-01

Reliability data are an essential part of probabilistic safety assessment. The quality of data can determine the quality of the study as a whole. It is obvious that component failure data originated from the plant being analyzed would be most appropriate. However, in few cases complete reliance on plant experience is possible, mainly because of the rather limited operating experience. Nuclear plants, although of different design, often use fairly similar components, so some of the experience could be combined and transferred from one plant to another. In addition information about component failures is available also from experts with knowledge on component design, manufacturing and operation. That bring us to the importance of assessing generic data. (Generic is meant to be everything that is not plant specific regarding the plant being analyzed). The generic data available in the open literature, can be divided in three broad categories. The first one includes data base used in previous analysis. These can be plant specific or updated from generic with plant specific information (latter case deserve special attention). The second one is based on compilation of plants' operating experience usually based on some kind of event reporting system. The third category includes data sources based on expert opinions (single or aggregate) or combination of expert opinions and other nuclear and non-nuclear experience. This paper reflects insights gained in compiling data from generic data sources and highlights advantages and pitfalls of using generic component reliability data in PSAs

THE EFFECT OF INQURY BASED LEARNING ON THE PROCEDURAL KNOWLEDGE DIMENSION ABOUT ELECTRIC AND MAGNET CONCEPT

Directory of Open Access Journals (Sweden)

Y. Yusrizal

2017-11-01

Full Text Available The purpose of this study to determine the effect of the use of inquiry-based learning to the increased dimensions of procedural knowledge in electrical magnetic material. The study used a quasi-experimental research methods with research design is non-equivalent control group design and a sampel are selected with the random sampling method. The experimental group was taught by the method of inquiry-based learning and the control group was taught by conventional methods. Collecting data using the instrument of multiple-choice test that developed through this research with category of validity is valid, reliability with category of reliable, index of discrimination with category of low, and level of difficulty with category of medium. The results of the data analysis by using the formula N-Gain and t-test showed that an increase in the dimensions of procedural knowledge siginificantly for experimental class and less significant for control class. Based on the results of this study suggested to the teacher to always use the method of inquiry learning that an increase in procedural knowledge dimension, especially for topics related to experimental physics.

Interactive Reliability-Based Optimal Design

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Thoft-Christensen, Palle; Siemaszko, A.

1994-01-01

Interactive design/optimization of large, complex structural systems is considered. The objective function is assumed to model the expected costs. The constraints are reliability-based and/or related to deterministic code requirements. Solution of this optimization problem is divided in four main...... tasks, namely finite element analyses, sensitivity analyses, reliability analyses and application of an optimization algorithm. In the paper it is shown how these four tasks can be linked effectively and how existing information on design variables, Lagrange multipliers and the Hessian matrix can...

Knowledge-based dialogue in Intelligent Decision Support Systems

International Nuclear Information System (INIS)

Hollnagel, E.

1987-01-01

The overall goal for the design of Intelligent Decision Support Systems (IDSS) is to enhance understanding of the process under all operating conditions. For an IDSS to be effective, it must: select or generate the right information; produce reliable and consistent information; allow flexible and effective operator interaction; relate information presentation to current plant status and problems; and make the presentation at the right time. Several ongoing R and D programs try to design and build IDSSs. A particular example is the ESPRIT project Graphics and Knowledge Based Diaglogue for Dynamic Systems (GRADIENT). This project, the problems it addresses, and its uses, are discussed here

A knowledge base architecture for distributed knowledge agents

Science.gov (United States)

Riedesel, Joel; Walls, Bryan

1990-01-01

A tuple space based object oriented model for knowledge base representation and interpretation is presented. An architecture for managing distributed knowledge agents is then implemented within the model. The general model is based upon a database implementation of a tuple space. Objects are then defined as an additional layer upon the database. The tuple space may or may not be distributed depending upon the database implementation. A language for representing knowledge and inference strategy is defined whose implementation takes advantage of the tuple space. The general model may then be instantiated in many different forms, each of which may be a distinct knowledge agent. Knowledge agents may communicate using tuple space mechanisms as in the LINDA model as well as using more well known message passing mechanisms. An implementation of the model is presented describing strategies used to keep inference tractable without giving up expressivity. An example applied to a power management and distribution network for Space Station Freedom is given.

The structure of surface texture knowledge

International Nuclear Information System (INIS)

Yan Wang; Scott, Paul J; Jiang Xiangqian

2005-01-01

This research aims to create an intelligent knowledge-based system for engineering and bio-medical engineering surface texture, which will provide expert knowledge of surface texture to link surface function, specification of micro- and nano-geometry through manufacture, and verification. The intelligent knowledge base should be capable of incorporating knowledge from multiple sources (standards, books, experts, etc), adding new knowledge from these sources and still remain a coherent reliable system. A new data model based on category theory will be adopted to construct this system

Development of an integrated knowledge-base and its management tool for computerized alarm processing system

International Nuclear Information System (INIS)

Heo, Gyun Young; Choi, Seong Soo; Kim, Han Gon; Chang, Soon Heung

1997-01-01

For a long time, a number of alarm processing techniques have been researched to reduce the number of actuated alarms for operators to deal with effectively during the abnormal as well as the normal conditions. However, the strategy that the only systems with a few clear technologies should be used as a part of an alarm annunciation system has been adopted considering the effectiveness and the reliability in actual alarm processing systems. Therefore, alarm processing systems have difficult knowledge-base maintenance problems and limited expansion or enhancement defects. To solve these shortcomings, the integrated knowledge-base which can express the general information related to all the alarm processing techniques is proposed and its management tool, Knowledge Input Tool for Alarm (KIT-A) which can handle the data of the knowledge-base efficiently is developed. Since the integrated knowledge-base with KIT-A can manipulate all the alarm information without the modification of alarm processing system itself, it is expected to considerably advance the overall capability of maintenance and enhancement of the alarm processing systems

Structural hybrid reliability index and its convergent solving method based on random–fuzzy–interval reliability model

OpenAIRE

Hai An; Ling Zhou; Hui Sun

2016-01-01

Aiming to resolve the problems of a variety of uncertainty variables that coexist in the engineering structure reliability analysis, a new hybrid reliability index to evaluate structural hybrid reliability, based on the random–fuzzy–interval model, is proposed in this article. The convergent solving method is also presented. First, the truncated probability reliability model, the fuzzy random reliability model, and the non-probabilistic interval reliability model are introduced. Then, the new...

Experiential Knowledge Complements an LCA-Based Decision Support Framework

Directory of Open Access Journals (Sweden)

Heng Yi Teah

2015-09-01

Full Text Available A shrimp farmer in Taiwan practices innovation through trial-and-error for better income and a better environment, but such farmer-based innovation sometimes fails because the biological mechanism is unclear. Systematic field experimentation and laboratory research are often too costly, and simulating ground conditions is often too challenging. To solve this dilemma, we propose a decision support framework that explicitly utilizes farmer experiential knowledge through a participatory approach to alternatively estimate prospective change in shrimp farming productivity, and to co-design options for improvement. Data obtained from the farmer enable us to quantitatively analyze the production cost and greenhouse gas (GHG emission with a life cycle assessment (LCA methodology. We used semi-quantitative graphical representations of indifference curves and mixing triangles to compare and show better options for the farmer. Our results empower the farmer to make decisions more systematically and reliably based on the frequency of heterotrophic bacteria application and the revision of feed input. We argue that experiential knowledge may be less accurate due to its dependence on varying levels of farmer experience, but this knowledge is a reasonable alternative for immediate decision-making. More importantly, our developed framework advances the scope of LCA application to support practically important yet scientifically uncertain cases.

Knowledge-based public health situation awareness

Science.gov (United States)

Mirhaji, Parsa; Zhang, Jiajie; Srinivasan, Arunkumar; Richesson, Rachel L.; Smith, Jack W.

2004-09-01

There have been numerous efforts to create comprehensive databases from multiple sources to monitor the dynamics of public health and most specifically to detect the potential threats of bioterrorism before widespread dissemination. But there are not many evidences for the assertion that these systems are timely and dependable, or can reliably identify man made from natural incident. One must evaluate the value of so called 'syndromic surveillance systems' along with the costs involved in design, development, implementation and maintenance of such systems and the costs involved in investigation of the inevitable false alarms1. In this article we will introduce a new perspective to the problem domain with a shift in paradigm from 'surveillance' toward 'awareness'. As we conceptualize a rather different approach to tackle the problem, we will introduce a different methodology in application of information science, computer science, cognitive science and human-computer interaction concepts in design and development of so called 'public health situation awareness systems'. We will share some of our design and implementation concepts for the prototype system that is under development in the Center for Biosecurity and Public Health Informatics Research, in the University of Texas Health Science Center at Houston. The system is based on a knowledgebase containing ontologies with different layers of abstraction, from multiple domains, that provide the context for information integration, knowledge discovery, interactive data mining, information visualization, information sharing and communications. The modular design of the knowledgebase and its knowledge representation formalism enables incremental evolution of the system from a partial system to a comprehensive knowledgebase of 'public health situation awareness' as it acquires new knowledge through interactions with domain experts or automatic discovery of new knowledge.

Logically automorphically equivalent knowledge bases

OpenAIRE

Aladova, Elena; Plotkin, Tatjana

2017-01-01

Knowledge bases theory provide an important example of the field where applications of universal algebra and algebraic logic look very natural, and their interaction with practical problems arising in computer science might be very productive. In this paper we study the equivalence problem for knowledge bases. Our interest is to find out how the informational equivalence is related to the logical description of knowledge. Studying various equivalences of knowledge bases allows us to compare d...

Reliability data bases: the current picture

International Nuclear Information System (INIS)

Fragola, J.R.

1985-01-01

The paper addresses specific advances in nuclear power plant reliability data base development, a critical review of a select set of relevant data bases and suggested future data bases and suggested future data development needs required for risk assessment techniques to reach full potential

Reliability Based Ship Structural Design

DEFF Research Database (Denmark)

Dogliani, M.; Østergaard, C.; Parmentier, G.

1996-01-01

This paper deals with the development of different methods that allow the reliability-based design of ship structures to be transferred from the area of research to the systematic application in current design. It summarises the achievements of a three-year collaborative research project dealing...... with developments of models of load effects and of structural collapse adopted in reliability formulations which aim at calibrating partial safety factors for ship structural design. New probabilistic models of still-water load effects are developed both for tankers and for containerships. New results are presented...... structure of several tankers and containerships. The results of the reliability analysis were the basis for the definition of a target safety level which was used to asses the partial safety factors suitable for in a new design rules format to be adopted in modern ship structural design. Finally...

An integrated reliability-based design optimization of offshore towers

International Nuclear Information System (INIS)

Karadeniz, Halil; Togan, Vedat; Vrouwenvelder, Ton

2009-01-01

After recognizing the uncertainty in the parameters such as material, loading, geometry and so on in contrast with the conventional optimization, the reliability-based design optimization (RBDO) concept has become more meaningful to perform an economical design implementation, which includes a reliability analysis and an optimization algorithm. RBDO procedures include structural analysis, reliability analysis and sensitivity analysis both for optimization and for reliability. The efficiency of the RBDO system depends on the mentioned numerical algorithms. In this work, an integrated algorithms system is proposed to implement the RBDO of the offshore towers, which are subjected to the extreme wave loading. The numerical strategies interacting with each other to fulfill the RBDO of towers are as follows: (a) a structural analysis program, SAPOS, (b) an optimization program, SQP and (c) a reliability analysis program based on FORM. A demonstration of an example tripod tower under the reliability constraints based on limit states of the critical stress, buckling and the natural frequency is presented.

An integrated reliability-based design optimization of offshore towers

Energy Technology Data Exchange (ETDEWEB)

Karadeniz, Halil [Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft (Netherlands)], E-mail: h.karadeniz@tudelft.nl; Togan, Vedat [Department of Civil Engineering, Karadeniz Technical University, Trabzon (Turkey); Vrouwenvelder, Ton [Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft (Netherlands)

2009-10-15

After recognizing the uncertainty in the parameters such as material, loading, geometry and so on in contrast with the conventional optimization, the reliability-based design optimization (RBDO) concept has become more meaningful to perform an economical design implementation, which includes a reliability analysis and an optimization algorithm. RBDO procedures include structural analysis, reliability analysis and sensitivity analysis both for optimization and for reliability. The efficiency of the RBDO system depends on the mentioned numerical algorithms. In this work, an integrated algorithms system is proposed to implement the RBDO of the offshore towers, which are subjected to the extreme wave loading. The numerical strategies interacting with each other to fulfill the RBDO of towers are as follows: (a) a structural analysis program, SAPOS, (b) an optimization program, SQP and (c) a reliability analysis program based on FORM. A demonstration of an example tripod tower under the reliability constraints based on limit states of the critical stress, buckling and the natural frequency is presented.

Reliability-Based Optimization of Series Systems of Parallel Systems

DEFF Research Database (Denmark)

Enevoldsen, I.; Sørensen, John Dalsgaard

1993-01-01

Reliability-based design of structural systems is considered. In particular, systems where the reliability model is a series system of parallel systems are treated. A sensitivity analysis for this class of problems is presented. Optimization problems with series systems of parallel systems...... optimization of series systems of parallel systems, but it is also efficient in reliability-based optimization of series systems in general....

Knowledge base verification based on enhanced colored petri net

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Hyun; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1998-12-31

Verification is a process aimed at demonstrating whether a system meets it`s specified requirements. As expert systems are used in various applications, the knowledge base verification of systems takes an important position. The conventional Petri net approach that has been studied recently in order to verify the knowledge base is found that it is inadequate to verify the knowledge base of large and complex system, such as alarm processing system of nuclear power plant. Thus, we propose an improved method that models the knowledge base as enhanced colored Petri net. In this study, we analyze the reachability and the error characteristics of the knowledge base and apply the method to verification of simple knowledge base. 8 refs., 4 figs. (Author)

Knowledge base verification based on enhanced colored petri net

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Hyun; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1997-12-31

Verification is a process aimed at demonstrating whether a system meets it`s specified requirements. As expert systems are used in various applications, the knowledge base verification of systems takes an important position. The conventional Petri net approach that has been studied recently in order to verify the knowledge base is found that it is inadequate to verify the knowledge base of large and complex system, such as alarm processing system of nuclear power plant. Thus, we propose an improved method that models the knowledge base as enhanced colored Petri net. In this study, we analyze the reachability and the error characteristics of the knowledge base and apply the method to verification of simple knowledge base. 8 refs., 4 figs. (Author)

Distributed, cooperating knowledge-based systems

Science.gov (United States)

Truszkowski, Walt

1991-01-01

Some current research in the development and application of distributed, cooperating knowledge-based systems technology is addressed. The focus of the current research is the spacecraft ground operations environment. The underlying hypothesis is that, because of the increasing size, complexity, and cost of planned systems, conventional procedural approaches to the architecture of automated systems will give way to a more comprehensive knowledge-based approach. A hallmark of these future systems will be the integration of multiple knowledge-based agents which understand the operational goals of the system and cooperate with each other and the humans in the loop to attain the goals. The current work includes the development of a reference model for knowledge-base management, the development of a formal model of cooperating knowledge-based agents, the use of testbed for prototyping and evaluating various knowledge-based concepts, and beginning work on the establishment of an object-oriented model of an intelligent end-to-end (spacecraft to user) system. An introductory discussion of these activities is presented, the major concepts and principles being investigated are highlighted, and their potential use in other application domains is indicated.

The Development of the IMIA Knowledge Base

Directory of Open Access Journals (Sweden)

Graham Wright

2011-03-01

Full Text Available Background: The discipline of health or medical informatics is relatively new in that the literature has existed for only 40 years. The British Computer Society (BCS health group was of the opinion that work should be undertaken to explore the scope of medical or health informatics. Once the mapping work was completed the International Medical Informatics Association (IMIA expressed the wish to develop it further to define the knowledge base of the discipline and produce a comprehensive internationally applicable framework. This article will also highlight the move from the expert opinion of a small group to the analysis of publications to generalise and refine the initial findings, and illustrate the importance of triangulation.Objectives: The aim of the project was to explore the theoretical constructs underpinning the discipline of health informatics and produce a cognitive map of the existing understanding of the discipline and develop the knowledge base of health informatics for the IMIA and the BCS.Method: The five-phase project, described in this article, undertaken to define the discipline of health informatics used four forms of triangulation.Results: The output from the project is a framework giving the 14 major headings (Subjects and 245 elements, which together describe the current perception of the discipline of health informatics.Conclusion: This article describes how each phase of the project was strengthened, through using triangulation within and between the different phases. This was done to ensure that the investigators could be confident in the confirmation and completeness of data, and assured of the validity and reliability of the final output of the ‘IMIA Knowledge Base’ that was endorsed by the IMIA Board in November 2009.

Reliability Assessment and Reliability-Based Inspection and Maintenance of Offshore Wind Turbines

DEFF Research Database (Denmark)

Ramírez, José G. Rangel; Sørensen, John Dalsgaard

2009-01-01

Probabilistic methodologies represent an important tool to identify the suitable strategy to inspect and deal with the deterioration in structures such as offshore wind turbines (OWT). Reliability based methods such as Risk Based Inspection (RBI) planning may represent a proper methodology to opt...

Mechanical reliability analysis of tubes intended for hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Nahal, Mourad; Khelif, Rabia [Badji Mokhtar University, Annaba (Algeria)

2013-02-15

Reliability analysis constitutes an essential phase in any study concerning reliability. Many industrialists evaluate and improve the reliability of their products during the development cycle - from design to startup (design, manufacture, and exploitation) - to develop their knowledge on cost/reliability ratio and to control sources of failure. In this study, we obtain results for hardness, tensile, and hydrostatic tests carried out on steel tubes for transporting hydrocarbons followed by statistical analysis. Results obtained allow us to conduct a reliability study based on resistance request. Thus, index of reliability is calculated and the importance of the variables related to the tube is presented. Reliability-based assessment of residual stress effects is applied to underground pipelines under a roadway, with and without active corrosion. Residual stress has been found to greatly increase probability of failure, especially in the early stages of pipe lifetime.

Component fragility data base for reliability and probability studies

International Nuclear Information System (INIS)

Bandyopadhyay, K.; Hofmayer, C.; Kassier, M.; Pepper, S.

1989-01-01

Safety-related equipment in a nuclear plant plays a vital role in its proper operation and control, and failure of such equipment due to an earthquake may pose a risk to the safe operation of the plant. Therefore, in order to assess the overall reliability of a plant, the reliability of performance of the equipment should be studied first. The success of a reliability or a probability study depends to a great extent on the data base. To meet this demand, Brookhaven National Laboratory (BNL) has formed a test data base relating the seismic capacity of equipment specimens to the earthquake levels. Subsequently, the test data have been analyzed for use in reliability and probability studies. This paper describes the data base and discusses the analysis methods. The final results that can be directly used in plant reliability and probability studies are also presented in this paper

Knowledge representation for integrated plant operation and maintenance

DEFF Research Database (Denmark)

Lind, Morten

2010-01-01

Integrated operation and maintenance of process plants has many advantages. One advantage is the improved economy obtained by reducing the number of plant shutdowns. Another is to increase reliability of operation by monitoring of risk levels during on-line maintenance. Integrated plant operation...... and maintenance require knowledge bases which can capture the interactions between the two plant activities. As an example, taking out a component or a subsystem for maintenance during operation will require a knowledge base representing the interactions between plant structure, functions, operating states...... and goals and incorporate knowledge about redundancy and reliability data. Multilevel Flow Modeling can be used build knowledge bases representing plant goals and functions and has been applied for fault diagnosis and supervisory control but currently it does not take into account structural information...

Community-based knowledge translation: unexplored opportunities

Directory of Open Access Journals (Sweden)

Armstrong Rebecca

2011-06-01

Full Text Available Abstract Background Knowledge translation is an interactive process of knowledge exchange between health researchers and knowledge users. Given that the health system is broad in scope, it is important to reflect on how definitions and applications of knowledge translation might differ by setting and focus. Community-based organizations and their practitioners share common characteristics related to their setting, the evidence used in this setting, and anticipated outcomes that are not, in our experience, satisfactorily reflected in current knowledge translation approaches, frameworks, or tools. Discussion Community-based organizations face a distinctive set of challenges and concerns related to engaging in the knowledge translation process, suggesting a unique perspective on knowledge translation in these settings. Specifically, community-based organizations tend to value the process of working in collaboration with multi-sector stakeholders in order to achieve an outcome. A feature of such community-based collaborations is the way in which 'evidence' is conceptualized or defined by these partners, which may in turn influence the degree to which generalizable research evidence in particular is relevant and useful when balanced against more contextually-informed knowledge, such as tacit knowledge. Related to the issues of evidence and context is the desire for local information. For knowledge translation researchers, developing processes to assist community-based organizations to adapt research findings to local circumstances may be the most helpful way to advance decision making in this area. A final characteristic shared by community-based organizations is involvement in advocacy activities, a function that has been virtually ignored in traditional knowledge translation approaches. Summary This commentary is intended to stimulate further discussion in the area of community-based knowledge translation. Knowledge translation, and exchange

Machine intelligence and knowledge bases

Energy Technology Data Exchange (ETDEWEB)

Furukawa, K

1981-09-01

The basic functions necessary in machine intelligence are a knowledge base and a logic programming language such as PROLOG using deductive reasoning. Recently inductive reasoning based on meta knowledge and default reasoning have been developed. The creative thought model of Lenit is reviewed and the concept of knowledge engineering is introduced. 17 references.

Statistical reliability assessment of software-based systems

International Nuclear Information System (INIS)

Korhonen, J.; Pulkkinen, U.; Haapanen, P.

1997-01-01

Plant vendors nowadays propose software-based systems even for the most critical safety functions. The reliability estimation of safety critical software-based systems is difficult since the conventional modeling techniques do not necessarily apply to the analysis of these systems, and the quantification seems to be impossible. Due to lack of operational experience and due to the nature of software faults, the conventional reliability estimation methods can not be applied. New methods are therefore needed for the safety assessment of software-based systems. In the research project Programmable automation systems in nuclear power plants (OHA), financed together by the Finnish Centre for Radiation and Nuclear Safety (STUK), the Ministry of Trade and Industry and the Technical Research Centre of Finland (VTT), various safety assessment methods and tools for software based systems are developed and evaluated. This volume in the OHA-report series deals with the statistical reliability assessment of software based systems on the basis of dynamic test results and qualitative evidence from the system design process. Other reports to be published later on in OHA-report series will handle the diversity requirements in safety critical software-based systems, generation of test data from operational profiles and handling of programmable automation in plant PSA-studies. (orig.) (25 refs.)

Evaluation of mobile ad hoc network reliability using propagation-based link reliability model

International Nuclear Information System (INIS)

Padmavathy, N.; Chaturvedi, Sanjay K.

2013-01-01

A wireless mobile ad hoc network (MANET) is a collection of solely independent nodes (that can move randomly around the area of deployment) making the topology highly dynamic; nodes communicate with each other by forming a single hop/multi-hop network and maintain connectivity in decentralized manner. MANET is modelled using geometric random graphs rather than random graphs because the link existence in MANET is a function of the geometric distance between the nodes and the transmission range of the nodes. Among many factors that contribute to the MANET reliability, the reliability of these networks also depends on the robustness of the link between the mobile nodes of the network. Recently, the reliability of such networks has been evaluated for imperfect nodes (transceivers) with binary model of communication links based on the transmission range of the mobile nodes and the distance between them. However, in reality, the probability of successful communication decreases as the signal strength deteriorates due to noise, fading or interference effects even up to the nodes' transmission range. Hence, in this paper, using a propagation-based link reliability model rather than a binary-model with nodes following a known failure distribution to evaluate the network reliability (2TR m , ATR m and AoTR m ) of MANET through Monte Carlo Simulation is proposed. The method is illustrated with an application and some imperative results are also presented

Application of Metric-based Software Reliability Analysis to Example Software

International Nuclear Information System (INIS)

Kim, Man Cheol; Smidts, Carol

2008-07-01

The software reliability of TELLERFAST ATM software is analyzed by using two metric-based software reliability analysis methods, a state transition diagram-based method and a test coverage-based method. The procedures for the software reliability analysis by using the two methods and the analysis results are provided in this report. It is found that the two methods have a relation of complementary cooperation, and therefore further researches on combining the two methods to reflect the benefit of the complementary cooperative effect to the software reliability analysis are recommended

A Temporal Fuzzy Logic Formalism for Knowledge Based Systems

Directory of Open Access Journals (Sweden)

Vasile MAZILESCU

2012-11-01

Full Text Available This paper shows that the influence of knowledge on new forms of work organisation can be described as mutual relationships. Different changes in work organisation also have a strong influence on the increasing importance of knowledge of different individual and collective actors in working situations. After that, we characterize a piece of basic formal system, an Extended Fuzzy Logic System (EFLS with temporal attributes, to conceptualize future DKMSs based on human imprecise for distributed just in time decisions. The approximate reasoning is perceived as a derivation of new formulas with the corresponding temporal attributes, within a fuzzy theory defined by the fuzzy set of special axioms. In a management application, the reasoning is evolutionary because of unexpected events which may change the state of the DKMS. In this kind of situations it is necessary to elaborate certain mechanisms in order to maintain the coherence of the obtained conclusions, to figure out their degree of reliability and the time domain for which these are true. These last aspects stand as possible further directions of development at a basic logic level for future technologies that must automate knowledge organizational processes.

Reliability assessment using Bayesian networks. Case study on quantative reliability estimation of a software-based motor protection relay

International Nuclear Information System (INIS)

Helminen, A.; Pulkkinen, U.

2003-06-01

In this report a quantitative reliability assessment of motor protection relay SPAM 150 C has been carried out. The assessment focuses to the methodological analysis of the quantitative reliability assessment using the software-based motor protection relay as a case study. The assessment method is based on Bayesian networks and tries to take the full advantage of the previous work done in a project called Programmable Automation System Safety Integrity assessment (PASSI). From the results and experiences achieved during the work it is justified to claim that the assessment method presented in the work enables a flexible use of qualitative and quantitative elements of reliability related evidence in a single reliability assessment. At the same time the assessment method is a concurrent way of reasoning one's beliefs and references about the reliability of the system. Full advantage of the assessment method is taken when using the method as a way to cultivate the information related to the reliability of software-based systems. The method can also be used as a communicational instrument in a licensing process of software-based systems. (orig.)

Reliability-based performance simulation for optimized pavement maintenance

International Nuclear Information System (INIS)

Chou, Jui-Sheng; Le, Thanh-Son

2011-01-01

Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: →A novel algorithm using multi-objective particle swarm optimization technique. → Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. → A probabilistic model for regression parameters is employed to assess reliability-based performance. → The proposed approach can help decision makers to optimize roadway maintenance plans.

Reliability-based performance simulation for optimized pavement maintenance

Energy Technology Data Exchange (ETDEWEB)

Chou, Jui-Sheng, E-mail: jschou@mail.ntust.edu.tw [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China); Le, Thanh-Son [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China)

2011-10-15

Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: > A novel algorithm using multi-objective particle swarm optimization technique. > Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. > A probabilistic model for regression parameters is employed to assess reliability-based performance. > The proposed approach can help decision makers to optimize roadway maintenance plans.

Placing knowledge

DEFF Research Database (Denmark)

Adriansen, Hanne Kirstine; Valentin, Karen; Nielsen, Gritt B.

; on the other hand, the rationale for strengthening mobility through internationalisation is based on an imagination of the potentials of particular locations (academic institutions). Intrigued by this tension between universality and particularity in academic knowledge production, this paper presents...... preliminary findings from a project that study internationalisation of higher education as an agent in the interrelated processes of place-making and knowledge-making. The project is based on three case-studies. In this paper, focus is on PhD students’ change of research environment. This is used as a case......Internationalisation of higher education is premised by a seeming paradox: On the one hand, academic knowledge strives to be universal in the sense that it claims to produce generalizable, valid and reliable knowledge that can be used, critiqued, and redeveloped by academics from all over the world...

Integrated Reliability-Based Optimal Design of Structures

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Thoft-Christensen, Palle

1987-01-01

In conventional optimal design of structural systems the weight or the initial cost of the structure is usually used as objective function. Further, the constraints require that the stresses and/or strains at some critical points have to be less than some given values. Finally, all variables......-based optimal design is discussed. Next, an optimal inspection and repair strategy for existing structural systems is presented. An optimization problem is formulated , where the objective is to minimize the expected total future cost of inspection and repair subject to the constraint that the reliability...... value. The reliability can be measured from an element and/or a systems point of view. A number of methods to solve reliability-based optimization problems has been suggested, see e.g. Frangopol [I]. Murotsu et al. (2], Thoft-Christensen & Sørensen (3] and Sørensen (4). For structures where...

Knowledge Based Economy Assessment

OpenAIRE

Madalina Cristina Tocan

2012-01-01

The importance of knowledge-based economy (KBE) in the XXI century is evident. In the article the reflection of knowledge on economy is analyzed. The main point is targeted to the analysis of characteristics of knowledge expression in economy and to the construction of structure of KBE expression. This allows understanding the mechanism of functioning of knowledge economy. The authors highlight the possibility to assess the penetration level of KBE which could manifest itself trough the exist...

Diabetes knowledge in nursing homes and home-based care services: a validation study of the Michigan Diabetes Knowledge Test adapted for use among nursing personnel.

Science.gov (United States)

Haugstvedt, Anne; Aarflot, Morten; Igland, Jannicke; Landbakk, Tilla; Graue, Marit

2016-01-01

Providing high-quality diabetes care in nursing homes and home-based care facilities requires suitable instruments to evaluate the level of diabetes knowledge among the health-care providers. Thus, the aim of this study was to examine the psychometric properties of the Michigan Diabetes Knowledge Test adapted for use among nursing personnel. The study included 127 nursing personnel (32 registered nurses, 69 nursing aides and 26 nursing assistants) at three nursing homes and one home-based care facility in Norway. We examined the reliability and content and construct validity of the Michigan Diabetes Knowledge Test. The items in both the general diabetes subscale and the insulin-use subscale were considered relevant and appropriate. The instrument showed satisfactory properties for distinguishing between groups. Item response theory-based measurements and item information curves indicate maximum information at average or lower knowledge scores. Internal consistency and the item-total correlations were quite weak, indicating that the Michigan Diabetes Knowledge Test measures a set of items related to various relevant knowledge topics but not necessarily related to each other. The Michigan Diabetes Knowledge Test measures a broad range of topics relevant to diabetes care. It is an appropriate instrument for identifying individual and distinct needs for diabetes education among nursing personnel. The knowledge gaps identified by the Michigan Diabetes Knowledge Test could also provide useful input for the content of educational activities. However, some revision of the test should be considered.

A full life cycle nuclear knowledge management framework based on digital system

International Nuclear Information System (INIS)

Wang, Minglu; Zheng, Mingguang; Tian, Lin; Qiu, Zhongming; Li, Xiaoyan

2017-01-01

Highlights: • A full life cycle nuclear power plant knowledge management framework is introduced. • This framework benefits the safe design, construction, operation and maintenance. • This framework enhances safety, economy and reliability of nuclear power plant. - Abstract: The nuclear power plant is highly knowledge-intensive facility. With the rapid advent and development of modern information and communication technology, knowledge management in nuclear industry has been provided with new approaches and possibilities. This paper introduces a full cycle nuclear power plant knowledge management framework based on digital system and tries to find solutions to knowledge creation, sharing, transfer, application and further innovation in nuclear industry. This framework utilizes information and digital technology to build top-tier object driven work environment, automatic design and analysis integration platform, digital dynamic performance Verification & Validation (V&V) platform, collaborative manufacture procedure, digital construction platform, online monitoring and configuration management which benefit knowledge management in NPP full life cycle. The suggested framework will strengthen the design basis of the nuclear power plants (NPPs) and will ensure the safety of the NPP design throughout the whole lifetime of the plant.

Knowledge Base Editor (SharpKBE)

Science.gov (United States)

Tikidjian, Raffi; James, Mark; Mackey, Ryan

2007-01-01

The SharpKBE software provides a graphical user interface environment for domain experts to build and manage knowledge base systems. Knowledge bases can be exported/translated to various target languages automatically, including customizable target languages.

Understanding images using knowledge based approach

International Nuclear Information System (INIS)

Tascini, G.

1985-01-01

This paper presents an approach to image understanding focusing on low level image processing and proposes a rule-based approach as part of larger knowledge-based system. The general system has a yerarchical structure that comprises several knowledge-based layers. The main idea is to confine at the lower level the domain independent knowledge and to reserve the higher levels for the domain dependent knowledge, that is for the interpretation

Reliability-based design code calibration for concrete containment structures

International Nuclear Information System (INIS)

Han, B.K.; Cho, H.N.; Chang, S.P.

1991-01-01

In this study, a load combination criteria for design and a probability-based reliability analysis were proposed on the basis of a FEM-based random vibration analysis. The limit state model defined for the study is a serviceability limit state of the crack failure that causes the emission of radioactive materials, and the results are compared with the case of strength limit state. More accurate reliability analyses under various dynamic loads such as earthquake loads were made possible by incorporating the FEM and random vibration theory, which is different from the conventional reliability analysis method. The uncertainties in loads and resistance available in Korea and the references were adapted to the situation of Korea, and especially in case of earthquake, the design earthquake was assessed based on the available data for the probabilistic description of earthquake ground acceleration in the Korea peninsula. The SAP V-2 is used for a three-dimensional finite element analysis of concrete containment structure, and the reliability analysis is carried out by modifying HRAS reliability analysis program for this study. (orig./GL)

Interactive Reliability-Based Optimization of Structural Systems

DEFF Research Database (Denmark)

Pedersen, Claus

In order to introduce the basic concepts within the field of reliability-based structural optimization problems, this chapter is devoted to a brief outline of the basic theories. Therefore, this chapter is of a more formal nature and used as a basis for the remaining parts of the thesis. In section...... 2.2 a general non-linear optimization problem and corresponding terminology are presented whereupon optimality conditions and the standard form of an iterative optimization algorithm are outlined. Subsequently, the special properties and characteristics concerning structural optimization problems...... are treated in section 2.3. With respect to the reliability evalutation, the basic theory behind a reliability analysis and estimation of probability of failure by the First-Order Reliability Method (FORM) and the iterative Rackwitz-Fiessler (RF) algorithm are considered in section 2.5 in which...

Reliability of microprocessor-based relay protection devices: Myths and reality

Directory of Open Access Journals (Sweden)

Gurevich Vladimir

2009-01-01

Full Text Available The article examines four basic theses about the ostensibly extremely high reliability of microprocessor-based relay protection (MP touted by supporters of MP. Through detailed analysis based on many references it is shown that the basis of these theses are widespread myths, and actually MP reliability is lower than the reliability of electromechanical and electronic protective relays on discrete components.

Reliability-Based Robustness Analysis for a Croatian Sports Hall

DEFF Research Database (Denmark)

Čizmar, Dean; Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

2011-01-01

This paper presents a probabilistic approach for structural robustness assessment for a timber structure built a few years ago. The robustness analysis is based on a structural reliability based framework for robustness and a simplified mechanical system modelling of a timber truss system....... A complex timber structure with a large number of failure modes is modelled with only a few dominant failure modes. First, a component based robustness analysis is performed based on the reliability indices of the remaining elements after the removal of selected critical elements. The robustness...... is expressed and evaluated by a robustness index. Next, the robustness is assessed using system reliability indices where the probabilistic failure model is modelled by a series system of parallel systems....

Reusing Design Knowledge Based on Design Cases and Knowledge Map

Science.gov (United States)

Yang, Cheng; Liu, Zheng; Wang, Haobai; Shen, Jiaoqi

2013-01-01

Design knowledge was reused for innovative design work to support designers with product design knowledge and help designers who lack rich experiences to improve their design capacity and efficiency. First, based on the ontological model of product design knowledge constructed by taxonomy, implicit and explicit knowledge was extracted from some…

Automated knowledge-base refinement

Science.gov (United States)

Mooney, Raymond J.

1994-01-01

Over the last several years, we have developed several systems for automatically refining incomplete and incorrect knowledge bases. These systems are given an imperfect rule base and a set of training examples and minimally modify the knowledge base to make it consistent with the examples. One of our most recent systems, FORTE, revises first-order Horn-clause knowledge bases. This system can be viewed as automatically debugging Prolog programs based on examples of correct and incorrect I/O pairs. In fact, we have already used the system to debug simple Prolog programs written by students in a programming language course. FORTE has also been used to automatically induce and revise qualitative models of several continuous dynamic devices from qualitative behavior traces. For example, it has been used to induce and revise a qualitative model of a portion of the Reaction Control System (RCS) of the NASA Space Shuttle. By fitting a correct model of this portion of the RCS to simulated qualitative data from a faulty system, FORTE was also able to correctly diagnose simple faults in this system.

Refining Automatically Extracted Knowledge Bases Using Crowdsourcing.

Science.gov (United States)

Li, Chunhua; Zhao, Pengpeng; Sheng, Victor S; Xian, Xuefeng; Wu, Jian; Cui, Zhiming

2017-01-01

Machine-constructed knowledge bases often contain noisy and inaccurate facts. There exists significant work in developing automated algorithms for knowledge base refinement. Automated approaches improve the quality of knowledge bases but are far from perfect. In this paper, we leverage crowdsourcing to improve the quality of automatically extracted knowledge bases. As human labelling is costly, an important research challenge is how we can use limited human resources to maximize the quality improvement for a knowledge base. To address this problem, we first introduce a concept of semantic constraints that can be used to detect potential errors and do inference among candidate facts. Then, based on semantic constraints, we propose rank-based and graph-based algorithms for crowdsourced knowledge refining, which judiciously select the most beneficial candidate facts to conduct crowdsourcing and prune unnecessary questions. Our experiments show that our method improves the quality of knowledge bases significantly and outperforms state-of-the-art automatic methods under a reasonable crowdsourcing cost.

Refining Automatically Extracted Knowledge Bases Using Crowdsourcing

Directory of Open Access Journals (Sweden)

Chunhua Li

2017-01-01

Full Text Available Machine-constructed knowledge bases often contain noisy and inaccurate facts. There exists significant work in developing automated algorithms for knowledge base refinement. Automated approaches improve the quality of knowledge bases but are far from perfect. In this paper, we leverage crowdsourcing to improve the quality of automatically extracted knowledge bases. As human labelling is costly, an important research challenge is how we can use limited human resources to maximize the quality improvement for a knowledge base. To address this problem, we first introduce a concept of semantic constraints that can be used to detect potential errors and do inference among candidate facts. Then, based on semantic constraints, we propose rank-based and graph-based algorithms for crowdsourced knowledge refining, which judiciously select the most beneficial candidate facts to conduct crowdsourcing and prune unnecessary questions. Our experiments show that our method improves the quality of knowledge bases significantly and outperforms state-of-the-art automatic methods under a reasonable crowdsourcing cost.

XML-Based SHINE Knowledge Base Interchange Language

Science.gov (United States)

James, Mark; Mackey, Ryan; Tikidjian, Raffi

2008-01-01

The SHINE Knowledge Base Interchange Language software has been designed to more efficiently send new knowledge bases to spacecraft that have been embedded with the Spacecraft Health Inference Engine (SHINE) tool. The intention of the behavioral model is to capture most of the information generally associated with a spacecraft functional model, while specifically addressing the needs of execution within SHINE and Livingstone. As such, it has some constructs that are based on one or the other.

Current trends on knowledge-based systems

CERN Document Server

Valencia-García, Rafael

2017-01-01

This book presents innovative and high-quality research on the implementation of conceptual frameworks, strategies, techniques, methodologies, informatics platforms and models for developing advanced knowledge-based systems and their application in different fields, including Agriculture, Education, Automotive, Electrical Industry, Business Services, Food Manufacturing, Energy Services, Medicine and others. Knowledge-based technologies employ artificial intelligence methods to heuristically address problems that cannot be solved by means of formal techniques. These technologies draw on standard and novel approaches from various disciplines within Computer Science, including Knowledge Engineering, Natural Language Processing, Decision Support Systems, Artificial Intelligence, Databases, Software Engineering, etc. As a combination of different fields of Artificial Intelligence, the area of Knowledge-Based Systems applies knowledge representation, case-based reasoning, neural networks, Semantic Web and TICs used...

Efficient approach for reliability-based optimization based on weighted importance sampling approach

International Nuclear Information System (INIS)

Yuan, Xiukai; Lu, Zhenzhou

2014-01-01

An efficient methodology is presented to perform the reliability-based optimization (RBO). It is based on an efficient weighted approach for constructing an approximation of the failure probability as an explicit function of the design variables which is referred to as the ‘failure probability function (FPF)’. It expresses the FPF as a weighted sum of sample values obtained in the simulation-based reliability analysis. The required computational effort for decoupling in each iteration is just single reliability analysis. After the approximation of the FPF is established, the target RBO problem can be decoupled into a deterministic one. Meanwhile, the proposed weighted approach is combined with a decoupling approach and a sequential approximate optimization framework. Engineering examples are given to demonstrate the efficiency and accuracy of the presented methodology

Case-based reasoning: The marriage of knowledge base and data base

Science.gov (United States)

Pulaski, Kirt; Casadaban, Cyprian

1988-01-01

The coupling of data and knowledge has a synergistic effect when building an intelligent data base. The goal is to integrate the data and knowledge almost to the point of indistinguishability, permitting them to be used interchangeably. Examples given in this paper suggest that Case-Based Reasoning is a more integrated way to link data and knowledge than pure rule-based reasoning.

Objectives, priorities, reliable knowledge, and science-based management of Missouri River interior least terns and piping plovers

Science.gov (United States)

Sherfy, Mark; Anteau, Michael J.; Shaffer, Terry; Sovada, Marsha; Stucker, Jennifer

2011-01-01

Supporting recovery of federally listed interior least tern (Sternula antillarum athalassos; tern) and piping plover (Charadrius melodus; plover) populations is a desirable goal in management of the Missouri River ecosystem. Many tools are implemented in support of this goal, including habitat management, annual monitoring, directed research, and threat mitigation. Similarly, many types of data can be used to make management decisions, evaluate system responses, and prioritize research and monitoring. The ecological importance of Missouri River recovery and the conservation status of terns and plovers place a premium on efficient and effective resource use. Efficiency is improved when a single data source informs multiple high-priority decisions, whereas effectiveness is improved when decisions are informed by reliable knowledge. Seldom will a single study design be optimal for addressing all data needs, making prioritization of needs essential. Data collection motivated by well-articulated objectives and priorities has many advantages over studies in which questions and priorities are determined retrospectively. Research and monitoring for terns and plovers have generated a wealth of data that can be interpreted in a variety of ways. The validity and strength of conclusions from analyses of these data is dependent on compatibility between the study design and the question being asked. We consider issues related to collection and interpretation of biological data, and discuss their utility for enhancing the role of science in management of Missouri River terns and plovers. A team of USGS scientists at Northern Prairie Wildlife Research Center has been conducting tern and plover research on the Missouri River since 2005. The team has had many discussions about the importance of setting objectives, identifying priorities, and obtaining reliable information to answer pertinent questions about tern and plover management on this river system. The objectives of this

A Hybrid Approach for Reliability Analysis Based on Analytic Hierarchy Process and Bayesian Network

International Nuclear Information System (INIS)

Zubair, Muhammad

2014-01-01

By using analytic hierarchy process (AHP) and Bayesian Network (BN) the present research signifies the technical and non-technical issues of nuclear accidents. The study exposed that the technical faults was one major reason of these accidents. Keep an eye on other point of view it becomes clearer that human behavior like dishonesty, insufficient training, and selfishness are also play a key role to cause these accidents. In this study, a hybrid approach for reliability analysis based on AHP and BN to increase nuclear power plant (NPP) safety has been developed. By using AHP, best alternative to improve safety, design, operation, and to allocate budget for all technical and non-technical factors related with nuclear safety has been investigated. We use a special structure of BN based on the method AHP. The graphs of the BN and the probabilities associated with nodes are designed to translate the knowledge of experts on the selection of best alternative. The results show that the improvement in regulatory authorities will decrease failure probabilities and increase safety and reliability in industrial area.

Effect of imperfect knowledge of hazards on the reliability of concrete face rockfill dam and breakwater

Directory of Open Access Journals (Sweden)

D. De León–Escobedo

2008-07-01

Full Text Available A formulation to treat aleatory and epistemic uncertainties, in a separate way, on infrastructures is proposed and applied to a dam and a breakwater in Mexico. The purpose of that is to de termine 2nd order bounds on the reliability estimation due to the in complete knowledge of some design parameters. These bounds provide a quantitative basis for risk management according to the risk–aversion of owners and operators of the infrastructure. Also, acceptable values of reliability, are assessed in terms of consequences costs, and an initial cost curve for a breakwater is presented, as they may contribute to enhance the decision making process.The in corporation of epistemic uncertainty makes the reliability index to become a random variable and its his to gram is obtained to estimate percentiles as a means to measure a new additional room for decisions as compared to the traditionally used mean value of the reliability. Conservative decisions are illustrated for design and assessment of structures like a dam and a breakwater.The procedure involves a double loop of Monte Carlo simulation and represents a basis for the optimal design and risk management of dams and breakwaters.

Reliability-based Assessment of Fatigue Life for Bridges

DEFF Research Database (Denmark)

Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

2012-01-01

The reliability level for bridges is discussed based on a comparison of the reliability levels proposed and used by e.g. JCSS, ISO, NKB and Eurocodes. The influence of reserve capacity by which failure of a specific detail does not lead to structural collapse is investigated. The results show...

Reliability evaluation of microgrid considering incentive-based demand response

Science.gov (United States)

Huang, Ting-Cheng; Zhang, Yong-Jun

2017-07-01

Incentive-based demand response (IBDR) can guide customers to adjust their behaviour of electricity and curtail load actively. Meanwhile, distributed generation (DG) and energy storage system (ESS) can provide time for the implementation of IBDR. The paper focus on the reliability evaluation of microgrid considering IBDR. Firstly, the mechanism of IBDR and its impact on power supply reliability are analysed. Secondly, the IBDR dispatch model considering customer’s comprehensive assessment and the customer response model are developed. Thirdly, the reliability evaluation method considering IBDR based on Monte Carlo simulation is proposed. Finally, the validity of the above models and method is studied through numerical tests on modified RBTS Bus6 test system. Simulation results demonstrated that IBDR can improve the reliability of microgrid.

Validation Of Critical Knowledge-Based Systems

Science.gov (United States)

Duke, Eugene L.

1992-01-01

Report discusses approach to verification and validation of knowledge-based systems. Also known as "expert systems". Concerned mainly with development of methodologies for verification of knowledge-based systems critical to flight-research systems; e.g., fault-tolerant control systems for advanced aircraft. Subject matter also has relevance to knowledge-based systems controlling medical life-support equipment or commuter railroad systems.

Reliability analysis for new technology-based transmitters

Energy Technology Data Exchange (ETDEWEB)

Brissaud, Florent, E-mail: florent.brissaud.2007@utt.f [Institut National de l' Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Universite de Technologie de Troyes (UTT), Institut Charles Delaunay (ICD) and STMR UMR CNRS 6279, 12 rue Marie Curie, BP 2060, 10010 Troyes cedex (France); Barros, Anne; Berenguer, Christophe [Universite de Technologie de Troyes (UTT), Institut Charles Delaunay (ICD) and STMR UMR CNRS 6279, 12 rue Marie Curie, BP 2060, 10010 Troyes cedex (France); Charpentier, Dominique [Institut National de l' Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France)

2011-02-15

The reliability analysis of new technology-based transmitters has to deal with specific issues: various interactions between both material elements and functions, undefined behaviours under faulty conditions, several transmitted data, and little reliability feedback. To handle these particularities, a '3-step' model is proposed, based on goal tree-success tree (GTST) approaches to represent both the functional and material aspects, and includes the faults and failures as a third part for supporting reliability analyses. The behavioural aspects are provided by relationship matrices, also denoted master logic diagrams (MLD), with stochastic values which represent direct relationships between system elements. Relationship analyses are then proposed to assess the effect of any fault or failure on any material element or function. Taking these relationships into account, the probabilities of malfunction and failure modes are evaluated according to time. Furthermore, uncertainty analyses tend to show that even if the input data and system behaviour are not well known, these previous results can be obtained in a relatively precise way. An illustration is provided by a case study on an infrared gas transmitter. These properties make the proposed model and corresponding reliability analyses especially suitable for intelligent transmitters (or 'smart sensors').

A method of knowledge base verification and validation for nuclear power plants expert systems

International Nuclear Information System (INIS)

Kwon, Il Won

1996-02-01

The adoption of expert systems mainly as operator supporting systems is becoming increasingly popular as the control algorithms of system become more and more sophisticated and complicated. As a result of this popularity, a large number of expert systems are developed. The nature of expert systems, however, requires that they be verified and validated carefully and that detailed methodologies for their development be devised. Therefore, it is widely noted that assuring the reliability of expert systems is very important, especially in nuclear industry, and it is also recognized that the process of verification and validation is an essential part of reliability assurance for these systems. Research and practices have produced numerous methods for expert system verification and validation (V and V) that suggest traditional software and system approaches to V and V. However, many approaches and methods for expert system V and V are partial, unreliable, and not uniform. The purpose of this paper is to present a new approach to expert system V and V, based on Petri nets, providing a uniform model. We devise and suggest an automated tool, called COKEP (Checker Of Knowledge base using Extended Petri net), for checking incorrectness, inconsistency, and incompleteness in a knowledge base. We also suggest heuristic analysis for validation process to show that the reasoning path is correct

[Validity, reliability, and acceptability of the brief version of the self-management knowledge, attitude, and behavior assessment scale for diabetes patients].

Science.gov (United States)

Wu, Y Z; Wang, W J; Feng, N P; Chen, B; Li, G C; Liu, J W; Liu, H L; Yang, Y Y

2016-07-06

To evaluate the validity, reliability, and acceptability of the brief version of the self-management knowledge, attitude, and behavior (KAB) assessment scale for diabetes patients. Diabetes patients who were managed at the Xinkaipu Community Health Service Center of Tianxin in Changsha, Hunan Province were selected for survey by cluster sampling. A total of 350 diabetes patients were surveyed using the brief scale to collect data on knowledge, attitudes, and behaviors of self-management. Content validity was evaluated by Pearson correlation coefficient between the brief scale and subscales of knowledge, attitude, and behavior. Structure validity was evaluated by factor analysis, and discrimination validity was evaluated by an independent sample t-test between the high-score and low-score groups. Reliability was tested by internal consistency reliability and split-half reliability. The evaluation indexes of internal consistency reliability were Cronbach's α coefficients, θ coefficient, and Ω coefficient. Acceptability was evaluated by valid response rate and completion time of the brief scale. A total of 346(98.9%) valid questionnaires were returned, with average survey time of (11.43±3.4) minutes. Average score of the brief scale was 78.85 ± 11.22; scores of the knowledge, attitude, and behavior subscales were 16.45 ± 4.42, 21.33 ± 2.03, and 41.07 ± 8.34, respectively. Pearson correlation coefficients between the brief scale and the knowledge, attitude, and behavior subscales were 0.92, 0.42, and 0.60, respectively; P-values were all less than 0.01, indicating that the face validity and content validity of the brief scale were achieved to a good level. The common factor cumulative variance contribution rate of the brief scale and three subscales was from 53.66% to 61.75%, which achieved more than 50% of the approved standard. There were 11 common factors; 41 of the total 42 items had factor loadings above 0.40 in their relevant common factor, indicating

Exchanging Description Logic Knowledge Bases

NARCIS (Netherlands)

Arenas, M.; Botoeva, E.; Calvanese, D.; Ryzhikov, V.; Sherkhonov, E.

2012-01-01

In this paper, we study the problem of exchanging knowledge between a source and a target knowledge base (KB), connected through mappings. Differently from the traditional database exchange setting, which considers only the exchange of data, we are interested in exchanging implicit knowledge. As

Querying Natural Logic Knowledge Bases

DEFF Research Database (Denmark)

Andreasen, Troels; Bulskov, Henrik; Jensen, Per Anker

2017-01-01

This paper describes the principles of a system applying natural logic as a knowledge base language. Natural logics are regimented fragments of natural language employing high level inference rules. We advocate the use of natural logic for knowledge bases dealing with querying of classes...... in ontologies and class-relationships such as are common in life-science descriptions. The paper adopts a version of natural logic with recursive restrictive clauses such as relative clauses and adnominal prepositional phrases. It includes passive as well as active voice sentences. We outline a prototype...... for partial translation of natural language into natural logic, featuring further querying and conceptual path finding in natural logic knowledge bases....

A heuristic-based approach for reliability importance assessment of energy producers

International Nuclear Information System (INIS)

Akhavein, A.; Fotuhi Firuzabad, M.

2011-01-01

Reliability of energy supply is one of the most important issues of service quality. On one hand, customers usually have different expectations for service reliability and price. On the other hand, providing different level of reliability at load points is a challenge for system operators. In order to take reasonable decisions and obviate reliability implementation difficulties, market players need to know impacts of their assets on system and load-point reliabilities. One tool to specify reliability impacts of assets is the criticality or reliability importance measure by which system components can be ranked based on their effect on reliability. Conventional methods for determination of reliability importance are essentially on the basis of risk sensitivity analysis and hence, impose prohibitive calculation burden in large power systems. An approach is proposed in this paper to determine reliability importance of energy producers from perspective of consumers or distribution companies in a composite generation and transmission system. In the presented method, while avoiding immense computational burden, the energy producers are ranked based on their rating, unavailability and impact on power flows in the lines connecting to the considered load points. Study results on the IEEE reliability test system show successful application of the proposed method. - Research highlights: → Required reliability level at load points is a concern in modern power systems. → It is important to assess reliability importance of energy producers or generators. → Generators can be ranked based on their impacts on power flow to a selected area. → Ranking of generators is an efficient tool to assess their reliability importance.

Reliability-Based Optimization of Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Tarp-Johansen, N.J.

2004-01-01

Reliability-based optimization of the main tower and monopile foundation of an offshore wind turbine is considered. Different formulations are considered of the objective function including benefits and building and failure costs of the wind turbine. Also different reconstruction policies in case...

Reliability analysis of cluster-based ad-hoc networks

International Nuclear Information System (INIS)

Cook, Jason L.; Ramirez-Marquez, Jose Emmanuel

2008-01-01

The mobile ad-hoc wireless network (MAWN) is a new and emerging network scheme that is being employed in a variety of applications. The MAWN varies from traditional networks because it is a self-forming and dynamic network. The MAWN is free of infrastructure and, as such, only the mobile nodes comprise the network. Pairs of nodes communicate either directly or through other nodes. To do so, each node acts, in turn, as a source, destination, and relay of messages. The virtue of a MAWN is the flexibility this provides; however, the challenge for reliability analyses is also brought about by this unique feature. The variability and volatility of the MAWN configuration makes typical reliability methods (e.g. reliability block diagram) inappropriate because no single structure or configuration represents all manifestations of a MAWN. For this reason, new methods are being developed to analyze the reliability of this new networking technology. New published methods adapt to this feature by treating the configuration probabilistically or by inclusion of embedded mobility models. This paper joins both methods together and expands upon these works by modifying the problem formulation to address the reliability analysis of a cluster-based MAWN. The cluster-based MAWN is deployed in applications with constraints on networking resources such as bandwidth and energy. This paper presents the problem's formulation, a discussion of applicable reliability metrics for the MAWN, and illustration of a Monte Carlo simulation method through the analysis of several example networks

A Reliability Based Model for Wind Turbine Selection

Directory of Open Access Journals (Sweden)

A.K. Rajeevan

2013-06-01

Full Text Available A wind turbine generator output at a specific site depends on many factors, particularly cut- in, rated and cut-out wind speed parameters. Hence power output varies from turbine to turbine. The objective of this paper is to develop a mathematical relationship between reliability and wind power generation. The analytical computation of monthly wind power is obtained from weibull statistical model using cubic mean cube root of wind speed. Reliability calculation is based on failure probability analysis. There are many different types of wind turbinescommercially available in the market. From reliability point of view, to get optimum reliability in power generation, it is desirable to select a wind turbine generator which is best suited for a site. The mathematical relationship developed in this paper can be used for site-matching turbine selection in reliability point of view.

A novel knowledge-based potential for RNA 3D structure evaluation

Science.gov (United States)

Yang, Yi; Gu, Qi; Zhang, Ben-Gong; Shi, Ya-Zhou; Shao, Zhi-Gang

2018-03-01

Ribonucleic acids (RNAs) play a vital role in biology, and knowledge of their three-dimensional (3D) structure is required to understand their biological functions. Recently structural prediction methods have been developed to address this issue, but a series of RNA 3D structures are generally predicted by most existing methods. Therefore, the evaluation of the predicted structures is generally indispensable. Although several methods have been proposed to assess RNA 3D structures, the existing methods are not precise enough. In this work, a new all-atom knowledge-based potential is developed for more accurately evaluating RNA 3D structures. The potential not only includes local and nonlocal interactions but also fully considers the specificity of each RNA by introducing a retraining mechanism. Based on extensive test sets generated from independent methods, the proposed potential correctly distinguished the native state and ranked near-native conformations to effectively select the best. Furthermore, the proposed potential precisely captured RNA structural features such as base-stacking and base-pairing. Comparisons with existing potential methods show that the proposed potential is very reliable and accurate in RNA 3D structure evaluation. Project supported by the National Science Foundation of China (Grants Nos. 11605125, 11105054, 11274124, and 11401448).

Refining Automatically Extracted Knowledge Bases Using Crowdsourcing

OpenAIRE

Li, Chunhua; Zhao, Pengpeng; Sheng, Victor S.; Xian, Xuefeng; Wu, Jian; Cui, Zhiming

2017-01-01

Machine-constructed knowledge bases often contain noisy and inaccurate facts. There exists significant work in developing automated algorithms for knowledge base refinement. Automated approaches improve the quality of knowledge bases but are far from perfect. In this paper, we leverage crowdsourcing to improve the quality of automatically extracted knowledge bases. As human labelling is costly, an important research challenge is how we can use limited human resources to maximize the quality i...

Nuclear Knowledge Innovations Assimilation: The Impact of Organizational Knowledge Frames and Triple Helix Dynamics of Knowledge Base

International Nuclear Information System (INIS)

Hossain, M. D.; Sultana, T.

2016-01-01

Full text: Previous research did not investigate the impact of the TH dynamics of knowledge innovations on the nuclear knowledge innovations adoption/assimilation in the organizational context. Hence, the recommendation of R&D policy reformulation seems too broad. These gaps are the prime motivators for the research. In the organizational context, we posit that TH dynamics of knowledge base innovation serves as complements to managers’ knowledge frames related to a technology innovation. We examine interactions between three knowledge frames—integration frame, opportunism frame, and policy knowledge frame, and two TH dynamics of knowledge innovations—bilateral TH dynamics of knowledge innovations and trilateral TH dynamics of knowledge innovations, and their relationship with the assimilation of nuclear knowledge innovations. We aim to research on the issues of the dynamics of knowledge base of innovations involving TH collaborations (university, industry and government) in Bangladesh as a new build nuclear project. As a result, we can find out the impact of TH collaborations on organizational nuclear knowledge innovations management as well as core institutional problems of the knowledge base of innovation systems in terms of R&D policy. Finally, findings identify lack in production of nuclear knowledge innovations and concrete recommendation of R&D policy reformulation. (author

A G-function-based reliability-based design methodology applied to a cam roller system

International Nuclear Information System (INIS)

Wang, W.; Sui, P.; Wu, Y.T.

1996-01-01

Conventional reliability-based design optimization methods treats the reliability function as an ordinary function and applies existing mathematical programming techniques to solve the design problem. As a result, the conventional approach requires nested loops with respect to g-function, and is very time consuming. A new reliability-based design method is proposed in this paper that deals with the g-function directly instead of the reliability function. This approach has the potential of significantly reducing the number of calls for g-function calculations since it requires only one full reliability analysis in a design iteration. A cam roller system in a typical high pressure fuel injection diesel engine is designed using both the proposed and the conventional approach. The proposed method is much more efficient for this application

End user interface and knowledge base editing system of CSPAR: a knowledge-based consultation system for preventive maintenance in nuclear plants

International Nuclear Information System (INIS)

Sinohara, Yasusi; Terano, Takao; Nishiyama, Takuya

1988-01-01

Consultation System for Prevention of Abnormal-event Recurrence (CSPAR) is a knowledge-based system to analyze the same kind of events to a given fault reported on a nuclear power plant and to give users some informations for effective measures preventing them. This report discusses the interfaces of CSPAR for both end-users and knowledge-base editors. The interfaces are highly interactive and multi-window oriented. The features are as follows: (1) The end-user interfaces has Japanese language processing facility, which enables the users to consult CSPAR with various synonims and related terms for knowledge-base handling; (2) The knowledge-base editing system is used by knowledge-base editors for maintaining the knowledge on both plants' equipments and abnormal events sequences. It has facilities for easy maintenance of knowledge-bases, which includes a graphic oriented browser, a knowledge-base retriever, and a knowledge-base checker. (author)

NHPP-Based Software Reliability Models Using Equilibrium Distribution

Science.gov (United States)

Xiao, Xiao; Okamura, Hiroyuki; Dohi, Tadashi

Non-homogeneous Poisson processes (NHPPs) have gained much popularity in actual software testing phases to estimate the software reliability, the number of remaining faults in software and the software release timing. In this paper, we propose a new modeling approach for the NHPP-based software reliability models (SRMs) to describe the stochastic behavior of software fault-detection processes. The fundamental idea is to apply the equilibrium distribution to the fault-detection time distribution in NHPP-based modeling. We also develop efficient parameter estimation procedures for the proposed NHPP-based SRMs. Through numerical experiments, it can be concluded that the proposed NHPP-based SRMs outperform the existing ones in many data sets from the perspective of goodness-of-fit and prediction performance.

Maximizing the knowledge base: Knowledge Base+ and the Global Open Knowledgebase

Directory of Open Access Journals (Sweden)

Liam Earney

2013-11-01

Full Text Available The motivation for the two projects discussed in this article is the simple premise that the current inaccuracies of data in the library supply chain are detrimental to the user experience, limit the ability of institutions to effectively manage their collections and that resolving them is increasingly unsustainable at the institutional level. Two projects, Knowledge Base+ (KB+ in the UK and Global Open Knowledgebase (GOKb in the USA, are working in cooperation with a range of other partners, and adopting a communitycentric approach to address these issues and broaden the scope and utility of knowledge bases more generally. The belief is that only through collaboration at a wide range of levels and on a number of fronts can these challenges be overcome.

Sociopathic Knowledge Bases: Correct Knowledge Can Be Harmful Even Given Unlimited Computation

Science.gov (United States)

1989-08-01

1757 I Sociopathic Knowledge Bases: Correct Knowledge Can Be Harmful Even Given Unlimited Computation DTIC5 by flELECTE 5David C. Wilkins and Yong...NUMBERSWOKNI PROGRAM RAT TSWOKUI 61153N RR04206 OC 443g-008 11 TITLE (Include Security Classification) Sociopathic Knowledge Bases: Correct Knowledge Can be...probabilistic rules are shown to be sociopathic and so this problem is very widespread. Sociopathicity has important consequences for rule induction

Health Care Leadership: Managing Knowledge Bases as Stakeholders.

Science.gov (United States)

Rotarius, Timothy

Communities are composed of many organizations. These organizations naturally form clusters based on common patterns of knowledge, skills, and abilities of the individual organizations. Each of these spontaneous clusters represents a distinct knowledge base. The health care knowledge base is shown to be the natural leader of any community. Using the Central Florida region's 5 knowledge bases as an example, each knowledge base is categorized as a distinct type of stakeholder, and then a specific stakeholder management strategy is discussed to facilitate managing both the cooperative potential and the threatening potential of each "knowledge base" stakeholder.

Reliability-Based Optimization of Series Systems of Parallel Systems

DEFF Research Database (Denmark)

Enevoldsen, I.; Sørensen, John Dalsgaard

Reliability-based design of structural systems is considered. Especially systems where the reliability model is a series system of parallel systems are analysed. A sensitivity analysis for this class of problems is presented. Direct and sequential optimization procedures to solve the optimization...

Knowledge based Entrepreneurship

DEFF Research Database (Denmark)

Heebøll, John

This book is dedicated enterprising people with a technical or a scientific background who consider commercializing ideas and inventions within their field of expertise via a new business activity or a new company. It aims at distilling experiences from many successful and not so successful start......-up ventures from the Technical University of Denmark, 1988 – 2008 into practical, portable knowledge that can be used by future knowledge-based entrepreneurs to set up new companies efficiently or to stay away from it; to do what’s needed and avoid the pitfalls....

Design of Composite Structures Using Knowledge-Based and Case Based Reasoning

Science.gov (United States)

Lambright, Jonathan Paul

1996-01-01

A method of using knowledge based and case based reasoning to assist designers during conceptual design tasks of composite structures was proposed. The cooperative use of heuristics, procedural knowledge, and previous similar design cases suggests a potential reduction in design cycle time and ultimately product lead time. The hypothesis of this work is that the design process of composite structures can be improved by using Case-Based Reasoning (CBR) and Knowledge-Based (KB) reasoning in the early design stages. The technique of using knowledge-based and case-based reasoning facilitates the gathering of disparate information into one location that is easily and readily available. The method suggests that the inclusion of downstream life-cycle issues into the conceptual design phase reduces potential of defective, and sub-optimal composite structures. Three industry experts were interviewed extensively. The experts provided design rules, previous design cases, and test problems. A Knowledge Based Reasoning system was developed using the CLIPS (C Language Interpretive Procedural System) environment and a Case Based Reasoning System was developed using the Design Memory Utility For Sharing Experiences (MUSE) xviii environment. A Design Characteristic State (DCS) was used to document the design specifications, constraints, and problem areas using attribute-value pair relationships. The DCS provided consistent design information between the knowledge base and case base. Results indicated that the use of knowledge based and case based reasoning provided a robust design environment for composite structures. The knowledge base provided design guidance from well defined rules and procedural knowledge. The case base provided suggestions on design and manufacturing techniques based on previous similar designs and warnings of potential problems and pitfalls. The case base complemented the knowledge base and extended the problem solving capability beyond the existence of

LED system reliability

NARCIS (Netherlands)

Driel, W.D. van; Yuan, C.A.; Koh, S.; Zhang, G.Q.

2011-01-01

This paper presents our effort to predict the system reliability of Solid State Lighting (SSL) applications. A SSL system is composed of a LED engine with micro-electronic driver(s) that supplies power to the optic design. Knowledge of system level reliability is not only a challenging scientific

Reliability prediction system based on the failure rate model for electronic components

International Nuclear Information System (INIS)

Lee, Seung Woo; Lee, Hwa Ki

2008-01-01

Although many methodologies for predicting the reliability of electronic components have been developed, their reliability might be subjective according to a particular set of circumstances, and therefore it is not easy to quantify their reliability. Among the reliability prediction methods are the statistical analysis based method, the similarity analysis method based on an external failure rate database, and the method based on the physics-of-failure model. In this study, we developed a system by which the reliability of electronic components can be predicted by creating a system for the statistical analysis method of predicting reliability most easily. The failure rate models that were applied are MILHDBK- 217F N2, PRISM, and Telcordia (Bellcore), and these were compared with the general purpose system in order to validate the effectiveness of the developed system. Being able to predict the reliability of electronic components from the stage of design, the system that we have developed is expected to contribute to enhancing the reliability of electronic components

Cultural and Rhetorical Bases for communicating knowledge in web based communities

DEFF Research Database (Denmark)

Kampf, Constance; Kommers, Piet

2008-01-01

Cultural and Rhetorical Bases for communicating knowledge in web based communities How can we extend learner-centred theories for educational technology to include, for instance, the cultural and rhetorical backgrounds which influence participants in online communities as they engage in knowledge...... via web-based communities the intersection of culture and rhetoric in web-based communication rhetoric and discourse in the process of communicating knowledge via technology heuristics for knowledge communication from teaching in online forums connections between identity and knowledge communication...... This call for papers invites papers focused on theoretical frameworks or empirical research which highlights the cultural and/or rhetorical aspects of communicating knowledge in web based communities. We are looking for work that brings together methods and perspectives across disciplines...

On the use of NDT Data for Reliability-Based Assessment of Existing Timber Structures

DEFF Research Database (Denmark)

Sousa, Hélder S.; Sørensen, John Dalsgaard; Kirkegaard, Poul Henning

2013-01-01

The objective of this paper is to address the possibilities of using non-destructive testing (NDT) data for updating information and obtaining adequate characterization of the reliability level of existing timber structures and, also, for assessing the evolution in time of performance...... of these structures when exposed to deterioration. By improving the knowledge upon the mechanical properties of timber, better and more substantiated decisions after a reliability safety assessment are aimed at. Bayesian methods are used to update the mechanical properties of timber and reliability assessment......, and information of NDT is also used to calibrate these models. The proposed approach is used for reliability assessment of different structural timber systems. Reliability of the structural system is assessed regarding the failure consequences of individual elements defined as key elements which were determined...

Reliability-based design optimization via high order response surface method

International Nuclear Information System (INIS)

Li, Hong Shuang

2013-01-01

To reduce the computational effort of reliability-based design optimization (RBDO), the response surface method (RSM) has been widely used to evaluate reliability constraints. We propose an efficient methodology for solving RBDO problems based on an improved high order response surface method (HORSM) that takes advantage of an efficient sampling method, Hermite polynomials and uncertainty contribution concept to construct a high order response surface function with cross terms for reliability analysis. The sampling method generates supporting points from Gauss-Hermite quadrature points, which can be used to approximate response surface function without cross terms, to identify the highest order of each random variable and to determine the significant variables connected with point estimate method. The cross terms between two significant random variables are added to the response surface function to improve the approximation accuracy. Integrating the nested strategy, the improved HORSM is explored in solving RBDO problems. Additionally, a sampling based reliability sensitivity analysis method is employed to reduce the computational effort further when design variables are distributional parameters of input random variables. The proposed methodology is applied on two test problems to validate its accuracy and efficiency. The proposed methodology is more efficient than first order reliability method based RBDO and Monte Carlo simulation based RBDO, and enables the use of RBDO as a practical design tool.

Knowledge management method for knowledge based BWR Core Operation Management System

Energy Technology Data Exchange (ETDEWEB)

Wada, Yutaka; Fukuzaki, Takaharu; Kobayashi, Yasuhiro

1989-03-01

A knowledge management method is proposed to support an except whose knowledge is stored in a knowledge base in the BWR Core Operation Management System. When the alterations in the operation plans are motivated by the expert after evaluating them, the method attempts to find the knowledge which must be modified and to give the expert guidances. In this way the resultant operation plans are improved by modifying values of referenced data. Using data dependency among data, which are defined and referred during inference, data to be modified are retrieved. In generating modification guidances, data reference and definition procedures are classified by syntactic analysis of knowledge. The modified data values are calculated with a sensitivity between the increment in the data to be modified and the resultant one in the performance of operation plans. The efficiency of the knowledge management by the proposed method, when applied to the knowledge based system including 500 pieces of knowledge for BWR control rod programming, is higher than that for interactive use of existing general purpose editors. (author).

Knowledge management method for knowledge based BWR Core Operation Management System

International Nuclear Information System (INIS)

Wada, Yutaka; Fukuzaki, Takaharu; Kobayashi, Yasuhiro

1989-01-01

A knowledge management method is proposed to support an except whose knowledge is stored in a knowledge base in the BWR Core Operation Management System. When the alterations in the operation plans are motivated by the expert after evaluating them, the method attempts to find the knowledge which must be modified and to give the expert guidances. In this way the resultant operation plans are improved by modifying values of referenced data. Using data dependency among data, which are defined and referred during inference, data to be modified are retrieved. In generating modification guidances, data reference and definition procedures are classified by syntactic analysis of knowledge. The modified data values are calculated with a sensitivity between the increment in the data to be modified and the resultant one in the performance of operation plans. The efficiency of the knowledge management by the proposed method, when applied to the knowledge based system including 500 pieces of knowledge for BWR control rod programming, is higher than that for interactive use of existing general purpose editors. (author)

Reliability and Validity of a Questionnaire to Measure Consumer Knowledge regarding Safe Practices to Prevent Microbiological Contamination in Restaurants

Science.gov (United States)

Uggioni, Paula Lazzarin; Salay, Elisabette

2013-01-01

Objective: The objective of this study was to develop a validated and reliable questionnaire to measure consumer knowledge regarding safe practices to prevent microbiological contamination in restaurants and commercial kitchens. Methods: Non-probabilistic samples of individuals were interviewed in the city of Campinas, Brazil. Questionnaire items…

Automated knowledge base development from CAD/CAE databases

Science.gov (United States)

Wright, R. Glenn; Blanchard, Mary

1988-01-01

Knowledge base development requires a substantial investment in time, money, and resources in order to capture the knowledge and information necessary for anything other than trivial applications. This paper addresses a means to integrate the design and knowledge base development process through automated knowledge base development from CAD/CAE databases and files. Benefits of this approach include the development of a more efficient means of knowledge engineering, resulting in the timely creation of large knowledge based systems that are inherently free of error.

Managing visitor sites in Svalbard: from a precautionary approach towards knowledge-based management

Directory of Open Access Journals (Sweden)

Kirstin Fangel

2012-05-01

Full Text Available Increased tourism in the Arctic calls for more knowledge to meet management challenges. This paper reviews existing knowledge of the effects of human use on vegetation, fauna and cultural heritage in Svalbard, and it addresses the need for site-specific knowledge for improved management. This paper draws upon scientific studies, knowledge held by management authorities and local people, the Governor's database on visitors and visited sites and our own data from landing sites we visited. There is a certain level of basic knowledge available, allowing us to roughly grade the vulnerability of sites. However, there is a thorough lack of site-specific data related to the management of single locations or groups of similar locations. Future research needs to address specific on-site challenges in the management of visitor sites. Relevant management models and measures are discussed. We contend that a shift away from a blanket application of the precautionary principle and towards a more integrated, site-specific and evidence-based management plan will contribute to more trusted and reliable, and thereby acceptable among stakeholders, decisions in the management of growing tourism activity in Svalbard.

Knowledge-based development in Singapore and Malaysia

OpenAIRE

Menkhoff, Thomas; Gerke, Solvay; Evers, Hans-Dieter; Chay, Yue Wah

2009-01-01

This paper addresses the question how knowledge is used to benefit the economic development of Singapore and Malaysia. Both countries have followed strict science policies to establish knowledge governance regimes for a knowledge-based economy. On the basis of empirical studies in both countries we show, how ethnic and religious diversity impact on the ability to develop an epistemic culture of knowledge sharing and ultimately an innovative knowledge-based economy.

Knowledge engineering thinking of maintenance

International Nuclear Information System (INIS)

2007-01-01

Maintenance optimization problem could not always settled mathematically and was obliged to use quasi-optimum solution with omitting non-formulated limiting condition or neglecting part of optimization object. In such a case knowledge engineering thinking was encouraged. Maintenance of complicated plant and artificial system should be considered from artificial object (equipment/facility hardware and system), technical information and knowledge base, and organizational and human aspect or society and institution. Comprehensive management system in organization and society was necessary not only for assuring integrity of equipment but also for attaining higher performance, reliability and economics of system. For better judgment it was important to share mechanism to make use of more information with organization or whole society. It was required to create database and data mining for knowledge base management system of maintenance. Maintenance was called 'last fortress' to assure quality such as reliability and safety of required function of equipment. Strategic approach to develop maintenance technology under cooperation was considered. Life extension R and D road map was launched in 2005. (T. Tanaka)

Knowledge base about earthquakes as a tool to minimize strong events consequences

Science.gov (United States)

Frolova, Nina; Bonnin, Jean; Larionov, Valery; Ugarov, Alexander; Kijko, Andrzej

2017-04-01

The paper describes the structure and content of the knowledge base on physical and socio-economical consequences of damaging earthquakes, which may be used for calibration of near real-time loss assessment systems based on simulation models for shaking intensity, damage to buildings and casualties estimates. Such calibration allows to compensate some factors which influence on reliability of expected damage and loss assessment in "emergency" mode. The knowledge base contains the description of past earthquakes' consequences for the area under study. It also includes the current distribution of built environment and population at the time of event occurrence. Computer simulation of the recorded in knowledge base events allow to determine the sets of regional calibration coefficients, including rating of seismological surveys, peculiarities of shaking intensity attenuation and changes in building stock and population distribution, in order to provide minimum error of damaging earthquakes loss estimations in "emergency" mode. References 1. Larionov, V., Frolova, N: Peculiarities of seismic vulnerability estimations. In: Natural Hazards in Russia, volume 6: Natural Risks Assessment and Management, Publishing House "Kruk", Moscow, 120-131, 2003. 2. Frolova, N., Larionov, V., Bonnin, J.: Data Bases Used In Worlwide Systems For Earthquake Loss Estimation In Emergency Mode: Wenchuan Earthquake. In Proc. TIEMS2010 Conference, Beijing, China, 2010. 3. Frolova N. I., Larionov V. I., Bonnin J., Sushchev S. P., Ugarov A. N., Kozlov M. A. Loss Caused by Earthquakes: Rapid Estimates. Natural Hazards Journal of the International Society for the Prevention and Mitigation of Natural Hazards, vol.84, ISSN 0921-030, Nat Hazards DOI 10.1007/s11069-016-2653

Nutrition and Physical Activity Knowledge Assessment: Development of Questionnaires and Evaluation of Reliability in African American and Latino Children

Science.gov (United States)

Roberts, Lindsay S.; Sharma, Sushma; Hudes, Mark L.; Fleming, Sharon E.

2012-01-01

Background: African-American and Latino children living in neighborhoods with a low-socioeconomic index are more at risk of obesity-associated metabolic disease than their higher socioeconomic index and/or white peers. Currently, consistent and reliable questionnaires to evaluate nutrition and physical activity knowledge in these children are…

A methodology for developing high-integrity knowledge base using document analysis and ECPN matrix analysis with backward simulation

International Nuclear Information System (INIS)

Park, Joo Hyun

1999-02-01

When transitions occur in large systems such as nuclear power plants (NPPs) or industrial process plants, it is often difficult to diagnose them. Various computer-based operator-aiding systems have been developed in order to help operators diagnose the transitions of the plants. In procedures for developing knowledge base system like operator-aiding systems, the knowledge acquisition and the knowledge base verification are core activities. This dissertation describes a knowledge acquisition method and a knowledge base verification method for developing high-integrity knowledge base system of NPP expert systems. The knowledge acquisition is one of the most difficult and time-consuming activities in developing knowledge base systems. There are two kinds of knowledge acquisition methods in view of knowledge sources. One is an acquisition method from human expert. This method, however, is not adequate to acquire the knowledge of NPP expert systems because the number of experts is not sufficient. In this work, we propose a novel knowledge acquisition method through documents analysis. The knowledge base can be built correctly, rapidly, and partially automatically through this method. This method is especially useful when it is difficult to find domain experts. Reliability of knowledge base systems depends on the quality of their knowledge base. Petri Net has been used to verify knowledge bases due to their formal outputs. The methods using Petri Net however are difficult to apply to large and complex knowledge bases because the Net becomes very large and complex. Also, with Petri Net, it is difficult to find proper input patterns that make anomalies occur. In order to overcome this difficulty, in this work, the anomaly candidates detection methods are developed based on Extended CPN (ECPN) matrix analysis. This work also defines the backward simulation of CPN to find compact input patterns for anomaly detection, which starts simulation from the anomaly candidates

Reliability research to nuclear power plant operators based on several methods

International Nuclear Information System (INIS)

Fang Xiang; Li Fu; Zhao Bingquan

2009-01-01

The paper utilizes many kinds of international reliability research methods, and summarizes the review of reliability research of Chinese nuclear power plant operators in past over ten years based on the simulator platform of nuclear power plant. The paper shows the necessity and feasibility of the research to nuclear power plant operators from many angles including human cognition reliability, fuzzy mathematics model and psychological research model, etc. It will be good to the safe operation of nuclear power plant based on many kinds of research methods to the reliability research of nuclear power plant operators. (authors)

An Algebraic Approach to Knowledge Bases Informational Equivalence

OpenAIRE

Plotkin, B.; Plotkin, T.

2003-01-01

In this paper we study the notion of knowledge from the positions of universal algebra and algebraic logic. We consider first order knowledge which is based on first order logic. We define categories of knowledge and knowledge bases. These notions are defined for the fixed subject of knowledge. The key notion of informational equivalence of two knowledge bases is introduced. We use the idea of equivalence of categories in this definition. We prove that for finite models there is a clear way t...

Stochastic Differential Equation-Based Flexible Software Reliability Growth Model

Directory of Open Access Journals (Sweden)

P. K. Kapur

2009-01-01

Full Text Available Several software reliability growth models (SRGMs have been developed by software developers in tracking and measuring the growth of reliability. As the size of software system is large and the number of faults detected during the testing phase becomes large, so the change of the number of faults that are detected and removed through each debugging becomes sufficiently small compared with the initial fault content at the beginning of the testing phase. In such a situation, we can model the software fault detection process as a stochastic process with continuous state space. In this paper, we propose a new software reliability growth model based on Itô type of stochastic differential equation. We consider an SDE-based generalized Erlang model with logistic error detection function. The model is estimated and validated on real-life data sets cited in literature to show its flexibility. The proposed model integrated with the concept of stochastic differential equation performs comparatively better than the existing NHPP-based models.

Reliability of "Google" for obtaining medical information

Directory of Open Access Journals (Sweden)

Mihir Kothari

2015-01-01

Full Text Available Internet is used by many patients to obtain relevant medical information. We assessed the impact of "Google" search on the knowledge of the parents whose ward suffered from squint. In 21 consecutive patients, the "Google" search improved the mean score of the correct answers from 47% to 62%. We found that "Google" search was useful and reliable source of information for the patients with regards to the disease etiopathogenesis and the problems caused by the disease. The internet-based information, however, was incomplete and not reliable with regards to the disease treatment.

Tools for the Knowledge-Based Organization

DEFF Research Database (Denmark)

Ravn, Ib

2002-01-01

exist. They include a Master’s degree in knowledge management, a web- or print-based intelligence hub for the knowledge society, collaboration with the Danish intellectual capital reporting project, ongoing research on expertise and ethics in knowledge workers, a comparative study of competence...

KNOWLEDGE AND XML BASED CAPP SYSTEM

Institute of Scientific and Technical Information of China (English)

ZHANG Shijie; SONG Laigang

2006-01-01

In order to enhance the intelligent level of system and improve the interactivity with other systems, a knowledge and XML based computer aided process planning (CAPP) system is implemented. It includes user management, bill of materials(BOM) management, knowledge based process planning, knowledge management and database maintaining sub-systems. This kind of nesting knowledge representation method the system provided can represent complicated arithmetic and logical relationship to deal with process planning tasks. With the representation and manipulation of XML based technological file, the system solves some important problems in web environment such as information interactive efficiency and refreshing of web page. The CAPP system is written in ASP VBScript, JavaScript, Visual C++ languages and Oracle database. At present, the CAPP system is running in Shenyang Machine Tools. The functions of it meet the requirements of enterprise production.

Adaptive Knowledge Management of Project-Based Learning

Science.gov (United States)

Tilchin, Oleg; Kittany, Mohamed

2016-01-01

The goal of an approach to Adaptive Knowledge Management (AKM) of project-based learning (PBL) is to intensify subject study through guiding, inducing, and facilitating development knowledge, accountability skills, and collaborative skills of students. Knowledge development is attained by knowledge acquisition, knowledge sharing, and knowledge…

Monitoring Knowledge Base (MKB)

Data.gov (United States)

U.S. Environmental Protection Agency — The Monitoring Knowledge Base (MKB) is a compilation of emissions measurement and monitoring techniques associated with air pollution control devices, industrial...

Reliability analysis based on the losses from failures.

Science.gov (United States)

Todinov, M T

2006-04-01

The conventional reliability analysis is based on the premise that increasing the reliability of a system will decrease the losses from failures. On the basis of counterexamples, it is demonstrated that this is valid only if all failures are associated with the same losses. In case of failures associated with different losses, a system with larger reliability is not necessarily characterized by smaller losses from failures. Consequently, a theoretical framework and models are proposed for a reliability analysis, linking reliability and the losses from failures. Equations related to the distributions of the potential losses from failure have been derived. It is argued that the classical risk equation only estimates the average value of the potential losses from failure and does not provide insight into the variability associated with the potential losses. Equations have also been derived for determining the potential and the expected losses from failures for nonrepairable and repairable systems with components arranged in series, with arbitrary life distributions. The equations are also valid for systems/components with multiple mutually exclusive failure modes. The expected losses given failure is a linear combination of the expected losses from failure associated with the separate failure modes scaled by the conditional probabilities with which the failure modes initiate failure. On this basis, an efficient method for simplifying complex reliability block diagrams has been developed. Branches of components arranged in series whose failures are mutually exclusive can be reduced to single components with equivalent hazard rate, downtime, and expected costs associated with intervention and repair. A model for estimating the expected losses from early-life failures has also been developed. For a specified time interval, the expected losses from early-life failures are a sum of the products of the expected number of failures in the specified time intervals covering the

Associating current knowledge with that of past experience based on knowledge about automata

Energy Technology Data Exchange (ETDEWEB)

Koenig, E C

1982-01-01

Important to the performance of interactive systems is the ability of its members to associate current knowledge with knowledge of past experience. Knowledge association results in greater detail of a current knowledge and is demonstrated through the use of examples. It is based on knowledge about automata and the knowledge structures are in the form of graphs. 11 references.

Knowledge-based operation and management of communications systems

Science.gov (United States)

Heggestad, Harold M.

1988-01-01

Expert systems techniques are being applied in operation and control of the Defense Communications System (DCS), which has the mission of providing reliable worldwide voice, data and message services for U.S. forces and commands. Thousands of personnel operate DCS facilities, and many of their functions match the classical expert system scenario: complex, skill-intensive environments with a full spectrum of problems in training and retention, cost containment, modernization, and so on. Two of these functions are: (1) fault isolation and restoral of dedicated circuits at Tech Control Centers, and (2) network management for the Defense Switched Network (the modernized dial-up voice system currently replacing AUTOVON). An expert system for the first of these is deployed for evaluation purposes at Andrews Air Force Base, and plans are being made for procurement of operational systems. In the second area, knowledge obtained with a sophisticated simulator is being embedded in an expert system. The background, design and status of both projects are described.

Knowledge base expert system control of spatial xenon oscillations in pressurized water reactors

International Nuclear Information System (INIS)

Alten, S.

1992-01-01

Nuclear reactor operators are required to pay special attention to spatial xenon oscillations during the load-follow operation of pressurized water reactors. They are expected to observe the axial offset of the core, and to estimate the correct time and amount of necessary control action based on heuristic rules given in axial xenon oscillations are knowledge intensive, and heuristic in nature. An expert system, ACES (Axial offset Control using Expert Systems) is developed to implement a heuristic constant axial offset control procedure to aid reactor operators in increasing the plant reliability by reducing the human error component of the failure probability. ACES is written in a production system language, OPS5, based on the forward chaining algorithm. It samples reactor data with a certain time interval in terms of measurable parameters, such as the power, period, and the axial offset of the core. It then processes the core status utilizing a set of equations which are used in a back of the envelope calculations by domain experts. Heuristic rules of ACES identify the control variable to be used among the full and part length control rods and boron concentration, while a knowledge base is used to determine the amount of control. ACES is designed as a set of generic rules to avoid reducing the system into a set of patterns. Instead ACES evaluates the system, determines the necessary corrective actions in terms of reactivity insertion, and provides this reactivity insertion using the control variables. The amount of control action is determined using a knowledge base which consists of the differential rod worth curves, and the boron reactivity worth of a given reactor. Having the reactor dependent parameters in its knowledge base, ACES is applicable to an arbitrary reactor for axial offset control purposes

A relational data-knowledge base system and its potential in developing a distributed data-knowledge system

Science.gov (United States)

Rahimian, Eric N.; Graves, Sara J.

1988-01-01

A new approach used in constructing a rational data knowledge base system is described. The relational database is well suited for distribution due to its property of allowing data fragmentation and fragmentation transparency. An example is formulated of a simple relational data knowledge base which may be generalized for use in developing a relational distributed data knowledge base system. The efficiency and ease of application of such a data knowledge base management system is briefly discussed. Also discussed are the potentials of the developed model for sharing the data knowledge base as well as the possible areas of difficulty in implementing the relational data knowledge base management system.

Structural reliability analysis based on the cokriging technique

International Nuclear Information System (INIS)

Zhao Wei; Wang Wei; Dai Hongzhe; Xue Guofeng

2010-01-01

Approximation methods are widely used in structural reliability analysis because they are simple to create and provide explicit functional relationships between the responses and variables in stead of the implicit limit state function. Recently, the kriging method which is a semi-parameter interpolation technique that can be used for deterministic optimization and structural reliability has gained popularity. However, to fully exploit the kriging method, especially in high-dimensional problems, a large number of sample points should be generated to fill the design space and this can be very expensive and even impractical in practical engineering analysis. Therefore, in this paper, a new method-the cokriging method, which is an extension of kriging, is proposed to calculate the structural reliability. cokriging approximation incorporates secondary information such as the values of the gradients of the function being approximated. This paper explores the use of the cokriging method for structural reliability problems by comparing it with the Kriging method based on some numerical examples. The results indicate that the cokriging procedure described in this work can generate approximation models to improve on the accuracy and efficiency for structural reliability problems and is a viable alternative to the kriging.

Reliability-based assessment of polyethylene pipe creep lifetime

International Nuclear Information System (INIS)

Khelif, Rabia; Chateauneuf, Alaa; Chaoui, Kamel

2007-01-01

Lifetime management of underground pipelines is mandatory for safe hydrocarbon transmission and distribution systems. The use of high-density polyethylene tubes subjected to internal pressure, external loading and environmental variations requires a reliability study in order to define the service limits and the optimal operating conditions. In service, the time-dependent phenomena, especially creep, take place during the pipe lifetime, leading to significant strength reduction. In this work, the reliability-based assessment of pipe lifetime models is carried out, in order to propose a probabilistic methodology for lifetime model selection and to determine the pipe safety levels as well as the most important parameters for pipeline reliability. This study is enhanced by parametric analysis on pipe configuration, gas pressure and operating temperature

Reliability-based assessment of polyethylene pipe creep lifetime

Energy Technology Data Exchange (ETDEWEB)

Khelif, Rabia [LaMI-UBP and IFMA, Campus de Clermont-Fd, Les Cezeaux, BP 265, 63175 Aubiere Cedex (France); LR3MI, Departement de Genie Mecanique, Universite Badji Mokhtar, BP 12, Annaba 23000 (Algeria)], E-mail: rabia.khelif@ifma.fr; Chateauneuf, Alaa [LGC-University Blaise Pascal, Campus des Cezeaux, BP 206, 63174 Aubiere Cedex (France)], E-mail: alaa.chateauneuf@polytech.univ-bpclermont.fr; Chaoui, Kamel [LR3MI, Departement de Genie Mecanique, Universite Badji Mokhtar, BP 12, Annaba 23000 (Algeria)], E-mail: chaoui@univ-annaba.org

2007-12-15

Lifetime management of underground pipelines is mandatory for safe hydrocarbon transmission and distribution systems. The use of high-density polyethylene tubes subjected to internal pressure, external loading and environmental variations requires a reliability study in order to define the service limits and the optimal operating conditions. In service, the time-dependent phenomena, especially creep, take place during the pipe lifetime, leading to significant strength reduction. In this work, the reliability-based assessment of pipe lifetime models is carried out, in order to propose a probabilistic methodology for lifetime model selection and to determine the pipe safety levels as well as the most important parameters for pipeline reliability. This study is enhanced by parametric analysis on pipe configuration, gas pressure and operating temperature.

Reliability-based trajectory optimization using nonintrusive polynomial chaos for Mars entry mission

Science.gov (United States)

Huang, Yuechen; Li, Haiyang

2018-06-01

This paper presents the reliability-based sequential optimization (RBSO) method to settle the trajectory optimization problem with parametric uncertainties in entry dynamics for Mars entry mission. First, the deterministic entry trajectory optimization model is reviewed, and then the reliability-based optimization model is formulated. In addition, the modified sequential optimization method, in which the nonintrusive polynomial chaos expansion (PCE) method and the most probable point (MPP) searching method are employed, is proposed to solve the reliability-based optimization problem efficiently. The nonintrusive PCE method contributes to the transformation between the stochastic optimization (SO) and the deterministic optimization (DO) and to the approximation of trajectory solution efficiently. The MPP method, which is used for assessing the reliability of constraints satisfaction only up to the necessary level, is employed to further improve the computational efficiency. The cycle including SO, reliability assessment and constraints update is repeated in the RBSO until the reliability requirements of constraints satisfaction are satisfied. Finally, the RBSO is compared with the traditional DO and the traditional sequential optimization based on Monte Carlo (MC) simulation in a specific Mars entry mission to demonstrate the effectiveness and the efficiency of the proposed method.

Problem-Oriented Corporate Knowledge Base Models on the Case-Based Reasoning Approach Basis

Science.gov (United States)

Gluhih, I. N.; Akhmadulin, R. K.

2017-07-01

One of the urgent directions of efficiency enhancement of production processes and enterprises activities management is creation and use of corporate knowledge bases. The article suggests a concept of problem-oriented corporate knowledge bases (PO CKB), in which knowledge is arranged around possible problem situations and represents a tool for making and implementing decisions in such situations. For knowledge representation in PO CKB a case-based reasoning approach is encouraged to use. Under this approach, the content of a case as a knowledge base component has been defined; based on the situation tree a PO CKB knowledge model has been developed, in which the knowledge about typical situations as well as specific examples of situations and solutions have been represented. A generalized problem-oriented corporate knowledge base structural chart and possible modes of its operation have been suggested. The obtained models allow creating and using corporate knowledge bases for support of decision making and implementing, training, staff skill upgrading and analysis of the decisions taken. The universal interpretation of terms “situation” and “solution” adopted in the work allows using the suggested models to develop problem-oriented corporate knowledge bases in different subject domains. It has been suggested to use the developed models for making corporate knowledge bases of the enterprises that operate engineer systems and networks at large production facilities.

Knowledge based economy in European Union

Directory of Open Access Journals (Sweden)

Ecaterina Stănculescu

2012-04-01

Full Text Available Nowadays we assist at a fundamental change from the economy based mainly on resources to the one based mostly on knowledge. The concept has been launched in the last decade of the past century. The knowledge became a production agent and a value creation instrument for whatever country and of course for an entire community like European Union which is constantly concerned by its development and competitiveness. This paper presents the principal characteristics of the present EU preoccupations with the expansion of a knowledge based economy through the 2020 European Development Strategy for smart, sustainable and inclusive economy, and especially for the Framework Programs (Framework Programme 7 and Competitiveness and Innovation Framework Programme.

Design of Korean nuclear reliability data-base network using a two-stage Bayesian concept

International Nuclear Information System (INIS)

Kim, T.W.; Jeong, K.S.; Chae, S.K.

1987-01-01

In an analysis of probabilistic risk, safety, and reliability of a nuclear power plant, the reliability data base (DB) must be established first. As the importance of the reliability data base increases, event reporting systems such as the US Nuclear Regulatory Commission's Licensee Event Report and the International Atomic Energy Agency's Incident Reporting System have been developed. In Korea, however, the systematic reliability data base is not yet available. Therefore, foreign data bases have been directly quoted in reliability analyses of Korean plants. In order to develop a reliability data base for Korean plants, the problem is which methodology is to be used, and the application limits of the selected method must be solved and clarified. After starting the commercial operation of Korea Nuclear Unit-1 (KNU-1) in 1978, six nuclear power plants have begun operation. Of these, only KNU-3 is a Canada Deuterium Uranium pressurized heavy-water reactor, and the others are all pressurized water reactors. This paper describes the proposed reliability data-base network (KNRDS) for Korean nuclear power plants in the context of two-stage Bayesian (TSB) procedure of Kaplan. It describes the concept of TSB to obtain the Korean-specific plant reliability data base, which is updated with the incorporation of both the reported generic reliability data and the operation experiences of similar plants

Translation and validation of the Malay version of the Stroke Knowledge Test

Directory of Open Access Journals (Sweden)

Siti Noorkhairina Sowtali

2016-04-01

Conclusions: Malay version Stroke Knowledge Test was a valid and reliable tool to assess educational needs and to evaluate stroke knowledge among participants of group-based stroke education programs in Malaysia.

A knowledge base browser using hypermedia

Science.gov (United States)

Pocklington, Tony; Wang, Lui

1990-01-01

A hypermedia system is being developed to browse CLIPS (C Language Integrated Production System) knowledge bases. This system will be used to help train flight controllers for the Mission Control Center. Browsing this knowledge base will be accomplished either by having navigating through the various collection nodes that have already been defined, or through the query languages.

An Intuitionistic Fuzzy Methodology for Component-Based Software Reliability Optimization

DEFF Research Database (Denmark)

Madsen, Henrik; Grigore, Albeanu; Popenţiuvlǎdicescu, Florin

2012-01-01

Component-based software development is the current methodology facilitating agility in project management, software reuse in design and implementation, promoting quality and productivity, and increasing the reliability and performability. This paper illustrates the usage of intuitionistic fuzzy...... degree approach in modelling the quality of entities in imprecise software reliability computing in order to optimize management results. Intuitionistic fuzzy optimization algorithms are proposed to be used for complex software systems reliability optimization under various constraints....

An evaluation of the multi-state node networks reliability using the traditional binary-state networks reliability algorithm

International Nuclear Information System (INIS)

Yeh, W.-C.

2003-01-01

A system where the components and system itself are allowed to have a number of performance levels is called the Multi-state system (MSS). A multi-state node network (MNN) is a generalization of the MSS without satisfying the flow conservation law. Evaluating the MNN reliability arises at the design and exploitation stage of many types of technical systems. Up to now, the known existing methods can only evaluate a special MNN reliability called the multi-state node acyclic network (MNAN) in which no cyclic is allowed. However, no method exists for evaluating the general MNN reliability. The main purpose of this article is to show first that each MNN reliability can be solved using any the traditional binary-state networks (TBSN) reliability algorithm with a special code for the state probability. A simple heuristic SDP algorithm based on minimal cuts (MC) for estimating the MNN reliability is presented as an example to show how the TBSN reliability algorithm is revised to solve the MNN reliability problem. To the author's knowledge, this study is the first to discuss the relationships between MNN and TBSN and also the first to present methods to solve the exact and approximated MNN reliability. One example is illustrated to show how the exact MNN reliability is obtained using the proposed algorithm

Reliability Evaluation of Machine Center Components Based on Cascading Failure Analysis

Science.gov (United States)

Zhang, Ying-Zhi; Liu, Jin-Tong; Shen, Gui-Xiang; Long, Zhe; Sun, Shu-Guang

2017-07-01

In order to rectify the problems that the component reliability model exhibits deviation, and the evaluation result is low due to the overlook of failure propagation in traditional reliability evaluation of machine center components, a new reliability evaluation method based on cascading failure analysis and the failure influenced degree assessment is proposed. A direct graph model of cascading failure among components is established according to cascading failure mechanism analysis and graph theory. The failure influenced degrees of the system components are assessed by the adjacency matrix and its transposition, combined with the Pagerank algorithm. Based on the comprehensive failure probability function and total probability formula, the inherent failure probability function is determined to realize the reliability evaluation of the system components. Finally, the method is applied to a machine center, it shows the following: 1) The reliability evaluation values of the proposed method are at least 2.5% higher than those of the traditional method; 2) The difference between the comprehensive and inherent reliability of the system component presents a positive correlation with the failure influenced degree of the system component, which provides a theoretical basis for reliability allocation of machine center system.

Improving the reliability of fuel Enusa; Mejora de la fiabilidad del combustible en Enusa

Energy Technology Data Exchange (ETDEWEB)

Choithramani, S.; Quecedo, M.

2015-07-01

ENUSA is committed to providing our customers with fuel designs that meet their needs for operational efficiency, power, energy, performance and reliability. ENUSAs current fuel designs, covering BWR and PWR technologies, incorporate highest performance with proven reliability features developed along nuclear power operation history. As of January 2015, ENUSA has manufactured more than 20.000 fuel assemblies (around half BWR and half PWR), with operating conditions reflecting varying reactor power densities, cycle lengths, operating strategies and water chemistry environments. This experience brings the knowledge to model our fuel behavior and acts as the principal instrument to identify and characterize the failure mechanisms of our fuel. Based on the information obtained from all this years of operation, ENUSA has progressively developed and implemented numerous mitigating actions identified upon the knowledge on failure mechanisms, which are the bases for the fuel reliability improvement program. Contemporaneously to this implementation, a positive trend on ENUSA fuel reliability has been observed. (Author)

Considerations about the implementation of a public knowledge base regarding nanotechnology

International Nuclear Information System (INIS)

Kimmig, Daniel; Marquardt, Clarissa; Nau, Katja; Schmidt, Andreas; Dickerhof, Markus

2014-01-01

Nanotechnology ranks among the key technologies that will bring fundamental changes to basic research, many industry sectors and daily life. However, consumers often miss reliable and understandable information on nanomaterials. To create this transparency, the DaNa project collects and evaluates the latest scientific literature before publishing these on the website www.nanoobjects.info. Though all published articles are designed to meet the needs of different recipient groups, a certain knowledge about nanomaterials is presumed due to the nanomaterial-specific structuring of the website. This poses a barrier for interested laymen who usually have a particular nano-related application in mind. These application-oriented facts on nanomaterials already exist on the website but are scattered throughout the different articles. To overcome this, we first analyzed the state of the scattered information and then assessed requirements for a new tool displaying these facts: storage of extracted knowledge in a homogenous way, visualization options and integration of the new database into the existing content management system. We therefore extended our backend to capture knowledge on a semantically higher level in a database called DaNaVis. Based on this database we can increase the accessibility of DaNa's project results by means of interactive visualization components. (paper)

49 CFR Appendix E to Part 238 - General Principles of Reliability-Based Maintenance Programs

Science.gov (United States)

2010-10-01

... STANDARDS Pt. 238, App. E Appendix E to Part 238—General Principles of Reliability-Based Maintenance... 49 Transportation 4 2010-10-01 2010-10-01 false General Principles of Reliability-Based... the design level of safety and reliability of the equipment; (2) To restore safety and reliability to...

Project-based knowledge in organizing open innovation

CERN Document Server

Comacchio, Anna; Pizzi, Claudio

2014-01-01

Enriching understanding of the current theoretical debate on project-based open innovation, ‘Project-based Knowledge in Organizing Open Innovation’ draws on innovation management literature and knowledge-based perspectives to investigate the relationship between knowledge development at project level and the strategic organization of open innovation. Addressing the still open issue of how the firm level should be complemented by studies at the project level of analysis, this book provides theoretical and empirical arguments on the advantages of a more fine-grained level of analysis to understand how firms organize their innovation processes across boundaries. The book also addresses the emerging interest in the management literature on project-based organizations, and on the relevance of project forms of organizing in a knowledge-based economy. Through field research in different industrial settings , this book provides empirical evidence on how firms design open innovation project-by-project and it will ...

Measuring reliability under epistemic uncertainty: Review on non-probabilistic reliability metrics

Directory of Open Access Journals (Sweden)

Kang Rui

2016-06-01

Full Text Available In this paper, a systematic review of non-probabilistic reliability metrics is conducted to assist the selection of appropriate reliability metrics to model the influence of epistemic uncertainty. Five frequently used non-probabilistic reliability metrics are critically reviewed, i.e., evidence-theory-based reliability metrics, interval-analysis-based reliability metrics, fuzzy-interval-analysis-based reliability metrics, possibility-theory-based reliability metrics (posbist reliability and uncertainty-theory-based reliability metrics (belief reliability. It is pointed out that a qualified reliability metric that is able to consider the effect of epistemic uncertainty needs to (1 compensate the conservatism in the estimations of the component-level reliability metrics caused by epistemic uncertainty, and (2 satisfy the duality axiom, otherwise it might lead to paradoxical and confusing results in engineering applications. The five commonly used non-probabilistic reliability metrics are compared in terms of these two properties, and the comparison can serve as a basis for the selection of the appropriate reliability metrics.

Reliability analysis of digital based I and C system

Energy Technology Data Exchange (ETDEWEB)

Kang, I. S.; Cho, B. S.; Choi, M. J. [KOPEC, Yongin (Korea, Republic of)

1999-10-01

Rapidly, digital technology is being widely applied in replacing analog component installed in existing plant and designing new nuclear power plant for control and monitoring system in Korea as well as in foreign countries. Even though many merits of digital technology, it is being faced with a new problem of reliability assurance. The studies for solving this problem are being performed vigorously in foreign countries. The reliability of KNGR Engineered Safety Features Component Control System (ESF-CCS), digital based I and C system, was analyzed to verify fulfillment of the ALWR EPRI-URD requirement for reliability analysis and eliminate hazards in design applied new technology. The qualitative analysis using FMEA and quantitative analysis using reliability block diagram were performed. The results of analyses are shown in this paper.

Knowledge-based diagnosis for aerospace systems

Science.gov (United States)

Atkinson, David J.

1988-01-01

The need for automated diagnosis in aerospace systems and the approach of using knowledge-based systems are examined. Research issues in knowledge-based diagnosis which are important for aerospace applications are treated along with a review of recent relevant research developments in Artificial Intelligence. The design and operation of some existing knowledge-based diagnosis systems are described. The systems described and compared include the LES expert system for liquid oxygen loading at NASA Kennedy Space Center, the FAITH diagnosis system developed at the Jet Propulsion Laboratory, the PES procedural expert system developed at SRI International, the CSRL approach developed at Ohio State University, the StarPlan system developed by Ford Aerospace, the IDM integrated diagnostic model, and the DRAPhys diagnostic system developed at NASA Langley Research Center.

Research on knowledge support technology for product innovation design based on quality function knowledge deployment

Directory of Open Access Journals (Sweden)

Kai Zhang

2016-06-01

Full Text Available Based on the analysis of the relationship between the process of product innovation design and knowledge, this article proposes a theoretical model of quality function knowledge deployment. In order to link up the product innovation design and the knowledge required by the designer, the iterative method of quality function knowledge deployment is refined, as well as the knowledge retrieval model and knowledge support model based on quality function knowledge deployment are established. In the whole life cycle of product design, in view of the different requirements for knowledge in conceptual design stage, components’ configuration stage, process planning stage, and production planning stage, the quality function knowledge deployment model could link up the required knowledge with the engineering characteristics, component characteristics, process characteristics, and production characteristics in the four stages using the mapping relationship between the function characteristics and the knowledge and help the designer to track the required knowledge for realizing product innovation design. In this article, an instance about rewinding machine is given to demonstrate the practicability and validity of product innovation design knowledge support technology based on quality function knowledge deployment.

Reliability based Robustness of Timber Structures through NDT Data Updating

DEFF Research Database (Denmark)

Sousa, Hélder S.; Sørensen, John Dalsgaard; Kirkegaard, Poul Henning

2011-01-01

This work presents a framework for reliability-based assessment of timber structures / members using data gathered from non-destructive test results. These results are used for modeling an update of the mechanical characteristics of timber, using Bayesian methods. Results gathered from ultrasound...... of the structure, thus, being possible to evaluate reliability based in time dependent factors, as well to categorize that structure in terms of robustness. For exemplification of the underlined concepts, three different types of structures are studied....

IAEA's experience in compiling a generic component reliability data base

International Nuclear Information System (INIS)

Tomic, B.; Lederman, L.

1991-01-01

Reliability data are essential in probabilistic safety assessment, with component reliability parameters being particularly important. Component failure data which is plant specific would be most appropriate but this is rather limited. However, similar components are used in different designs. Generic data, that is all data that is not plant specific to the plant being analyzed but which relates to components more generally, is important. The International Atomic Energy Agency has compiled the Generic Component Reliability Data Base from data available in the open literature. It is part of the IAEA computer code package for fault/event tree analysis. The Data Base contains 1010 different records including most of the components used in probabilistic safety analyses of nuclear power plants. The data base input was quality controlled and data sources noted. The data compilation procedure and problems associated with using generic data are explained. (UK)

Process fault diagnosis using knowledge-based systems

International Nuclear Information System (INIS)

Sudduth, A.L.

1991-01-01

Advancing technology in process plants has led to increased need for computer based process diagnostic systems to assist the operator. One approach to this problem is to use an embedded knowledge based system to interpret measurement signals. Knowledge based systems using only symptom based rules are inadequate for real time diagnosis of dynamic systems; therefore a model based approach is necessary. Though several forms of model based reasoning have been proposed, the use of qualitative causal models incorporating first principles knowledge of process behavior structure, and function appear to have the most promise as a robust modeling methodology. In this paper the structure of a diagnostic system is described which uses model based reasoning and conventional numerical methods to perform process diagnosis. This system is being applied to emergency diesel generator system in nuclear stations

The Relationship between Agriculture Knowledge Bases for Teaching and Sources of Knowledge

Science.gov (United States)

Rice, Amber H.; Kitchel, Tracy

2015-01-01

The purpose of this study was to describe the agriculture knowledge bases for teaching of agriculture teachers and to see if a relationship existed between years of teaching experience, sources of knowledge, and development of pedagogical content knowledge (PCK), using quantitative methods. A model of PCK from mathematics was utilized as a…

On uncertainty in information and ignorance in knowledge

Science.gov (United States)

Ayyub, Bilal M.

2010-05-01

This paper provides an overview of working definitions of knowledge, ignorance, information and uncertainty and summarises formalised philosophical and mathematical framework for their analyses. It provides a comparative examination of the generalised information theory and the generalised theory of uncertainty. It summarises foundational bases for assessing the reliability of knowledge constructed as a collective set of justified true beliefs. It discusses system complexity for ancestor simulation potentials. It offers value-driven communication means of knowledge and contrarian knowledge using memes and memetics.

Reliability-Based Decision Fusion in Multimodal Biometric Verification Systems

Directory of Open Access Journals (Sweden)

Kryszczuk Krzysztof

2007-01-01

Full Text Available We present a methodology of reliability estimation in the multimodal biometric verification scenario. Reliability estimation has shown to be an efficient and accurate way of predicting and correcting erroneous classification decisions in both unimodal (speech, face, online signature and multimodal (speech and face systems. While the initial research results indicate the high potential of the proposed methodology, the performance of the reliability estimation in a multimodal setting has not been sufficiently studied or evaluated. In this paper, we demonstrate the advantages of using the unimodal reliability information in order to perform an efficient biometric fusion of two modalities. We further show the presented method to be superior to state-of-the-art multimodal decision-level fusion schemes. The experimental evaluation presented in this paper is based on the popular benchmarking bimodal BANCA database.

Selection of personalized patient therapy through the use of knowledge-based computational models that identify tumor-driving signal transduction pathways.

Science.gov (United States)

Verhaegh, Wim; van Ooijen, Henk; Inda, Márcia A; Hatzis, Pantelis; Versteeg, Rogier; Smid, Marcel; Martens, John; Foekens, John; van de Wiel, Paul; Clevers, Hans; van de Stolpe, Anja

2014-06-01

Increasing knowledge about signal transduction pathways as drivers of cancer growth has elicited the development of "targeted drugs," which inhibit aberrant signaling pathways. They require a companion diagnostic test that identifies the tumor-driving pathway; however, currently available tests like estrogen receptor (ER) protein expression for hormonal treatment of breast cancer do not reliably predict therapy response, at least in part because they do not adequately assess functional pathway activity. We describe a novel approach to predict signaling pathway activity based on knowledge-based Bayesian computational models, which interpret quantitative transcriptome data as the functional output of an active signaling pathway, by using expression levels of transcriptional target genes. Following calibration on only a small number of cell lines or cohorts of patient data, they provide a reliable assessment of signaling pathway activity in tumors of different tissue origin. As proof of principle, models for the canonical Wnt and ER pathways are presented, including initial clinical validation on independent datasets from various cancer types. ©2014 American Association for Cancer Research.

Adhesives technology for electronic applications materials, processing, reliability

CERN Document Server

Licari, James J

2011-01-01

Adhesives are widely used in the manufacture and assembly of electronic circuits and products. Generally, electronics design engineers and manufacturing engineers are not well versed in adhesives, while adhesion chemists have a limited knowledge of electronics. This book bridges these knowledge gaps and is useful to both groups. The book includes chapters covering types of adhesive, the chemistry on which they are based, and their properties, applications, processes, specifications, and reliability. Coverage of toxicity, environmental impacts and the regulatory framework make this book par

Knowledge-Basing Teaching Professions and Professional Practice

DEFF Research Database (Denmark)

Thingstrup, Signe Hvid

This paper discusses the demand for knowledge-based practice and two different answers to this demand, namely evidence-based thinking and critical-political thinking. The paper discusses the implications these have for views on knowledge and professional development. The paper presents and discus...

Force-based and displacement-based reliability assessment approaches for highway bridges under multiple hazard actions

Directory of Open Access Journals (Sweden)

Chao Huang

2015-08-01

Full Text Available The strength limit state of American Association of State Highway and Transportation Officials (AASHTO Load and Resistance Factor Design (LRFD Bridge Design Specifications is developed based on the failure probabilities of the combination of non-extreme loads. The proposed design limit state equation (DLSE has been fully calibrated for dead load and live load by using the reliability-based approach. On the other hand, most of DLSEs in other limit states, including the extreme events Ⅰ and Ⅱ, have not been developed and calibrated though taking certain probability-based concepts into account. This paper presents an assessment procedure of highway bridge reliabilities under the limit state of extreme event Ⅰ, i. e., the combination of dead load, live load and earthquake load. A force-based approach and a displacement-based approach are proposed and implemented on a set of nine simplified bridge models. Results show that the displacement-based approach comes up with more convergent and accurate reliabilities for selected models, which can be applied to other hazards.

Optimal Reliability-Based Code Calibration

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Kroon, I. B.; Faber, Michael Havbro

1994-01-01

Calibration of partial safety factors is considered in general, including classes of structures where no code exists beforehand. The partial safety factors are determined such that the difference between the reliability for the different structures in the class considered and a target reliability...... level is minimized. Code calibration on a decision theoretical basis is also considered and it is shown how target reliability indices can be calibrated. Results from code calibration for rubble mound breakwater designs are shown....

Diagnostic reliability of MMPI-2 computer-based test interpretations.

Science.gov (United States)

Pant, Hina; McCabe, Brian J; Deskovitz, Mark A; Weed, Nathan C; Williams, John E

2014-09-01

Reflecting the common use of the MMPI-2 to provide diagnostic considerations, computer-based test interpretations (CBTIs) also typically offer diagnostic suggestions. However, these diagnostic suggestions can sometimes be shown to vary widely across different CBTI programs even for identical MMPI-2 profiles. The present study evaluated the diagnostic reliability of 6 commercially available CBTIs using a 20-item Q-sort task developed for this study. Four raters each sorted diagnostic classifications based on these 6 CBTI reports for 20 MMPI-2 profiles. Two questions were addressed. First, do users of CBTIs understand the diagnostic information contained within the reports similarly? Overall, diagnostic sorts of the CBTIs showed moderate inter-interpreter diagnostic reliability (mean r = .56), with sorts for the 1/2/3 profile showing the highest inter-interpreter diagnostic reliability (mean r = .67). Second, do different CBTIs programs vary with respect to diagnostic suggestions? It was found that diagnostic sorts of the CBTIs had a mean inter-CBTI diagnostic reliability of r = .56, indicating moderate but not strong agreement across CBTIs in terms of diagnostic suggestions. The strongest inter-CBTI diagnostic agreement was found for sorts of the 1/2/3 profile CBTIs (mean r = .71). Limitations and future directions are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Validity and reliability of the Spanish version of the Organizational Readiness for Knowledge Translation (OR4KT questionnaire

Directory of Open Access Journals (Sweden)

Gonzalo Grandes

2017-11-01

Full Text Available Abstract Background Organizational readiness to change healthcare practice is a major determinant of successful implementation of evidence-based interventions. However, we lack of comprehensive, valid, and reliable instruments to measure it. We assessed the validity and reliability of the Spanish version of the Organizational Readiness for Knowledge Translation (OR4KT questionnaire in the context of the implementation of the Prescribe Vida Saludable III project, which seeks to strengthen health promotion and chronic disease prevention in primary healthcare organizations of the Osakidetza (Basque Health Service, Spain. Methods A cross-sectional study was conducted including 127 professionals from 20 primary care centers within Osakidetza. They filled in the OR4KT questionnaire twice in a 15- to 30-day period to test repeatability. In addition, we used the Survey of Organizational Attributes for Primary Care (SOAPC and we documented the number of healthcare professionals who formally engaged in the Prescribe Vida Saludable III project within each participating center to assess concurrent validity. Results Cronbach’s alpha for the overall OR4KT was .95, and the overall repeatability coefficient was 6.95%, both excellent results. Confirmatory factor analysis supported the underlying theoretical structure of 6 dimensions and 23 sub-dimensions. There were positive moderate-to-high internal correlations between these six dimensions, and there was evidence of good concurrent validity (correlation coefficient of .76 with SOAPC, and .80 with the proportion of professionals engaged by center. A score higher than 64 (out of 100 would be indicative of an organization with high level of readiness to implement the intervention (sensitivity = .75, specificity = 1. Conclusions The Spanish version of the OR4KT exhibits very strong reliability and good validity, although it needs to be validated in a larger sample and in different implementation contexts.

Validity and reliability of the Spanish version of the Organizational Readiness for Knowledge Translation (OR4KT) questionnaire.

Science.gov (United States)

Grandes, Gonzalo; Bully, Paola; Martinez, Catalina; Gagnon, Marie-Pierre

2017-11-10

Organizational readiness to change healthcare practice is a major determinant of successful implementation of evidence-based interventions. However, we lack of comprehensive, valid, and reliable instruments to measure it. We assessed the validity and reliability of the Spanish version of the Organizational Readiness for Knowledge Translation (OR4KT) questionnaire in the context of the implementation of the Prescribe Vida Saludable III project, which seeks to strengthen health promotion and chronic disease prevention in primary healthcare organizations of the Osakidetza (Basque Health Service, Spain). A cross-sectional study was conducted including 127 professionals from 20 primary care centers within Osakidetza. They filled in the OR4KT questionnaire twice in a 15- to 30-day period to test repeatability. In addition, we used the Survey of Organizational Attributes for Primary Care (SOAPC) and we documented the number of healthcare professionals who formally engaged in the Prescribe Vida Saludable III project within each participating center to assess concurrent validity. Cronbach's alpha for the overall OR4KT was .95, and the overall repeatability coefficient was 6.95%, both excellent results. Confirmatory factor analysis supported the underlying theoretical structure of 6 dimensions and 23 sub-dimensions. There were positive moderate-to-high internal correlations between these six dimensions, and there was evidence of good concurrent validity (correlation coefficient of .76 with SOAPC, and .80 with the proportion of professionals engaged by center). A score higher than 64 (out of 100) would be indicative of an organization with high level of readiness to implement the intervention (sensitivity = .75, specificity = 1). The Spanish version of the OR4KT exhibits very strong reliability and good validity, although it needs to be validated in a larger sample and in different implementation contexts.

Towards Modeling False Memory With Computational Knowledge Bases.

Science.gov (United States)

Li, Justin; Kohanyi, Emma

2017-01-01

One challenge to creating realistic cognitive models of memory is the inability to account for the vast common-sense knowledge of human participants. Large computational knowledge bases such as WordNet and DBpedia may offer a solution to this problem but may pose other challenges. This paper explores some of these difficulties through a semantic network spreading activation model of the Deese-Roediger-McDermott false memory task. In three experiments, we show that these knowledge bases only capture a subset of human associations, while irrelevant information introduces noise and makes efficient modeling difficult. We conclude that the contents of these knowledge bases must be augmented and, more important, that the algorithms must be refined and optimized, before large knowledge bases can be widely used for cognitive modeling. Copyright © 2016 Cognitive Science Society, Inc.

Measurement-based reliability/performability models

Science.gov (United States)

Hsueh, Mei-Chen

1987-01-01

Measurement-based models based on real error-data collected on a multiprocessor system are described. Model development from the raw error-data to the estimation of cumulative reward is also described. A workload/reliability model is developed based on low-level error and resource usage data collected on an IBM 3081 system during its normal operation in order to evaluate the resource usage/error/recovery process in a large mainframe system. Thus, both normal and erroneous behavior of the system are modeled. The results provide an understanding of the different types of errors and recovery processes. The measured data show that the holding times in key operational and error states are not simple exponentials and that a semi-Markov process is necessary to model the system behavior. A sensitivity analysis is performed to investigate the significance of using a semi-Markov process, as opposed to a Markov process, to model the measured system.

Human reliability analysis of performing tasks in plants based on fuzzy integral

International Nuclear Information System (INIS)

Washio, Takashi; Kitamura, Yutaka; Takahashi, Hideaki

1991-01-01

The effective improvement of the human working conditions in nuclear power plants might be a solution for the enhancement of the operation safety. The human reliability analysis (HRA) gives a methodological basis of the improvement based on the evaluation of human reliability under various working conditions. This study investigates some difficulties of the human reliability analysis using conventional linear models and recent fuzzy integral models, and provides some solutions to the difficulties. The following practical features of the provided methods are confirmed in comparison with the conventional methods: (1) Applicability to various types of tasks (2) Capability of evaluating complicated dependencies among working condition factors (3) A priori human reliability evaluation based on a systematic task analysis of human action processes (4) A conversion scheme to probability from indices representing human reliability. (author)

Automatic Knowledge Base Evolution by Learning Instances

OpenAIRE

Kim, Sundong

2016-01-01

Knowledge base is the way to store structured and unstructured data throughout the web. Since the size of the web is increasing rapidly, there are huge needs to structure the knowledge in a fully automated way. However fully-automated knowledge-base evolution on the Semantic Web is a major challenges, although there are many ontology evolution techniques available. Therefore learning ontology automatically can contribute to the semantic web society significantly. In this paper, we propose ful...

Investigation on Reliability and Scalability of an FBG-Based Hierarchical AOFSN

Directory of Open Access Journals (Sweden)

Li-Mei Peng

2010-03-01

Full Text Available The reliability and scalability of large-scale based optical fiber sensor networks (AOFSN are considered in this paper. The AOFSN network consists of three-level hierarchical sensor network architectures. The first two levels consist of active interrogation and remote nodes (RNs and the third level, called the sensor subnet (SSN, consists of passive Fiber Bragg Gratings (FBGs and a few switches. The switch architectures in the RN and various SSNs to improve the reliability and scalability of AOFSN are studied. Two SSNs with a regular topology are proposed to support simple routing and scalability in AOFSN: square-based sensor cells (SSC and pentagon-based sensor cells (PSC. The reliability and scalability are evaluated in terms of the available sensing coverage in the case of one or multiple link failures.

Reliability Based Optimization of Fire Protection

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

fire protection (PFP) of firewalls and structural members. The paper is partly based on research performed within the EU supported research project B/E-4359 "Optimized Fire Safety of Offshore Structures" and partly on research supported by the Danish Technical Research Council (see Thoft-Christensen [1......]). Special emphasis is put on the optimization software developed within the project.......It is well known that fire is one of the major risks of serious damage or total loss of several types of structures such as nuclear installations, buildings, offshore platforms/topsides etc. This paper presents a methodology and software for reliability based optimization of the layout of passive...

Skills, rules and knowledge in aircraft maintenance: errors in context

Science.gov (United States)

Hobbs, Alan; Williamson, Ann

2002-01-01

Automatic or skill-based behaviour is generally considered to be less prone to error than behaviour directed by conscious control. However, researchers who have applied Rasmussen's skill-rule-knowledge human error framework to accidents and incidents have sometimes found that skill-based errors appear in significant numbers. It is proposed that this is largely a reflection of the opportunities for error which workplaces present and does not indicate that skill-based behaviour is intrinsically unreliable. In the current study, 99 errors reported by 72 aircraft mechanics were examined in the light of a task analysis based on observations of the work of 25 aircraft mechanics. The task analysis identified the opportunities for error presented at various stages of maintenance work packages and by the job as a whole. Once the frequency of each error type was normalized in terms of the opportunities for error, it became apparent that skill-based performance is more reliable than rule-based performance, which is in turn more reliable than knowledge-based performance. The results reinforce the belief that industrial safety interventions designed to reduce errors would best be directed at those aspects of jobs that involve rule- and knowledge-based performance.

From Evidence-based Management to Management of Non-knowledge

DEFF Research Database (Denmark)

Knudsen, Morten

2017-01-01

Leadership and management are increasingly expected to base themselves on evidence, i.e. knowledge. This article does not disagree that knowledge may be beneficial. Yet, based on sociological insights on the complex relation between knowledge and ignorance, the article argues that more knowledge...

Knowledge Based Help desk System in Nuclear Malaysia

International Nuclear Information System (INIS)

Mohamad Safuan Sulaiman; Abdul Muin Abdul Rahman; Norzalina Nasirudin; Khairiel Adyani Abdul Ghani; Abdul Aziz Mhd Ramli; Mohd Ashhar Khalid

2012-01-01

Knowledge based (K-based) Help desk system is a knowledge oriented web based system that provides support to business process of the technical service providers. It is a multi-centric system which focuses on end-users, technical workers and higher level management through utilization of knowledge which resides and grows within the system. The objectives of the system are to be a user-friendly, capture technical knowledge for efficient performance and educating users for self reliance. These were achieved through the improvement of the help desk business process and better management of technical knowledge. This system has been tested and implemented in Information Technology Center (IT), Engineering Division (BKJ) and Instrumentation and Automation Center (IAC) at the Malaysian Nuclear Agency (Nuclear Malaysia). Higher levels of user satisfaction and faster growth in technical knowledge repository have been recorded in the system. This paper describes the help desk system in the perspective of management of its technical knowledge contributing to strengthening organizational knowledge asset of Nuclear Malaysia as national nuclear research institution. (Author)

A guide on the elicitation of expert knowledge in constructing BBN for quantitative reliability assessment of safety critical software

International Nuclear Information System (INIS)

Eom, H. S.; Kang, H. G.; Chang, S. C.; Ha, J. J.

2003-08-01

This report describes the methodology which could elicit probabilistic representation from the experts' knowledge or qualitative data. It is necessary to elicit expert's knowledge while we quantitatively assess the reliability of safety critical software using Bayesian Belief Nets(BBNs). Especially in composing the node probability table and in making out the input data for BBN model, experts' qualitative judgment or qualitative data should be converted into probabilistic representation. This conversion process is vulnerable to bias or error. The purpose of the report is to provide the guideline to avoid the occurrence of this kinds of bias/error or to eliminate them which is included in the existing data prepared by experts. The contents of the report are: o The types and the explanation of bias and error The types of bias and error which might be occur in the process of eliciting the expert's knowledge. o The procedure of expert's judgment elicitation. The process and techniques to avoid bias and error in eliciting the expert's judgments. o The examples of expert's knowledge appeared in the BBNs The examples of expert's knowledge (probability values) appeared in the BBNs for assessing the safety of digital system

Validation of an instrument to assess evidence-based practice knowledge, attitudes, access, and confidence in the dental environment.

Science.gov (United States)

Hendricson, William D; Rugh, John D; Hatch, John P; Stark, Debra L; Deahl, Thomas; Wallmann, Elizabeth R

2011-02-01

This article reports the validation of an assessment instrument designed to measure the outcomes of training in evidence-based practice (EBP) in the context of dentistry. Four EBP dimensions are measured by this instrument: 1) understanding of EBP concepts, 2) attitudes about EBP, 3) evidence-accessing methods, and 4) confidence in critical appraisal. The instrument-the Knowledge, Attitudes, Access, and Confidence Evaluation (KACE)-has four scales, with a total of thirty-five items: EBP knowledge (ten items), EBP attitudes (ten), accessing evidence (nine), and confidence (six). Four elements of validity were assessed: consistency of items within the KACE scales (extent to which items within a scale measure the same dimension), discrimination (capacity to detect differences between individuals with different training or experience), responsiveness (capacity to detect the effects of education on trainees), and test-retest reliability. Internal consistency of scales was assessed by analyzing responses of second-year dental students, dental residents, and dental faculty members using Cronbach coefficient alpha, a statistical measure of reliability. Discriminative validity was assessed by comparing KACE scores for the three groups. Responsiveness was assessed by comparing pre- and post-training responses for dental students and residents. To measure test-retest reliability, the full KACE was completed twice by a class of freshman dental students seventeen days apart, and the knowledge scale was completed twice by sixteen faculty members fourteen days apart. Item-to-scale consistency ranged from 0.21 to 0.78 for knowledge, 0.57 to 0.83 for attitude, 0.70 to 0.84 for accessing evidence, and 0.87 to 0.94 for confidence. For discrimination, ANOVA and post hoc testing by the Tukey-Kramer method revealed significant score differences among students, residents, and faculty members consistent with education and experience levels. For responsiveness to training, dental students

Latest scientific and technological knowledge of human-reliability quantification - December 1991

International Nuclear Information System (INIS)

Berg, H.P.; Schott, H.

1992-02-01

Again an again real incidents and accidents show that human factors may seriously affect the safety of plants. This is also true for, e.g. nuclear facilities. The major methods which are used to quantify the reliability of humans are described. These methods are applied in the framework of German and international risk analyses. Since in probabilistic safety analyses data bases are of great importance of the, however, naturally very difficult quantitative evaluation of human errors, the study also discusses the present limits to the treatment of human misbehavior in safety analyses. (orig.) [de

Terminological reference of a knowledge-based system: the data dictionary.

Science.gov (United States)

Stausberg, J; Wormek, A; Kraut, U

1995-01-01

The development of open and integrated knowledge bases makes new demands on the definition of the used terminology. The definition should be realized in a data dictionary separated from the knowledge base. Within the works done at a reference model of medical knowledge, a data dictionary has been developed and used in different applications: a term definition shell, a documentation tool and a knowledge base. The data dictionary includes that part of terminology, which is largely independent of a certain knowledge model. For that reason, the data dictionary can be used as a basis for integrating knowledge bases into information systems, for knowledge sharing and reuse and for modular development of knowledge-based systems.

Failures of knowledge production in nuclear power risk management

International Nuclear Information System (INIS)

Sanne, Johan M.

2008-09-01

Risks are ascribed in processes of knowledge production, where risk objects are defined and measures taken. This knowledge is also the basis for regulatory action. Thus, uncertainties in knowledge production, based upon choices of assumptions, methods, calculations and evidence criteria for reliable data create vulnerabilities for risk management and risk regulation. A recent incident in Swedish nuclear power plant provides an opportunity to develop theories of knowledge production in complex organizations. Knowledge modes within nuclear power can be characterized as either calculated logics where evidence claims need numbers, real time logics based upon subtle signals and tacit knowledge or as policy logics, navigating between internal and external demands for safety, trustworthiness and profit. The plant had neither foreseen the triggering event nor designed the plant to withstand it. I analyze how the plant and the regulator have interpreted the event, its significance and the measures taken to prevent similar events. I also discuss alternative interpretations, lack of knowledge and the generic deficiencies in knowledge production that the event indicates. First, the plant was not as robustly designed as expected. Deficiencies in diversification may have been caused by overconfidence in the reliability of its design. Second, inadequate design was ascribed to various deficient knowledge production processes: original design of the plant, reconstruction or caused by inadequate learning from previous events. The failures in knowledge production were probably caused by insufficient integration of different knowledge processes and limitations in engineering analysis. Knowledge about risks from nuclear power operations is mainly based upon calculations and simulations, not upon real events. But knowledge and design could be improved also without accidents. Control room operators and maintenance staff can provide invaluable knowledge and methods; to improve causal

Failures of knowledge production in nuclear power risk management

Energy Technology Data Exchange (ETDEWEB)

Sanne, Johan M.

2008-09-15

Risks are ascribed in processes of knowledge production, where risk objects are defined and measures taken. This knowledge is also the basis for regulatory action. Thus, uncertainties in knowledge production, based upon choices of assumptions, methods, calculations and evidence criteria for reliable data create vulnerabilities for risk management and risk regulation. A recent incident in Swedish nuclear power plant provides an opportunity to develop theories of knowledge production in complex organizations. Knowledge modes within nuclear power can be characterized as either calculated logics where evidence claims need numbers, real time logics based upon subtle signals and tacit knowledge or as policy logics, navigating between internal and external demands for safety, trustworthiness and profit. The plant had neither foreseen the triggering event nor designed the plant to withstand it. I analyze how the plant and the regulator have interpreted the event, its significance and the measures taken to prevent similar events. I also discuss alternative interpretations, lack of knowledge and the generic deficiencies in knowledge production that the event indicates. First, the plant was not as robustly designed as expected. Deficiencies in diversification may have been caused by overconfidence in the reliability of its design. Second, inadequate design was ascribed to various deficient knowledge production processes: original design of the plant, reconstruction or caused by inadequate learning from previous events. The failures in knowledge production were probably caused by insufficient integration of different knowledge processes and limitations in engineering analysis. Knowledge about risks from nuclear power operations is mainly based upon calculations and simulations, not upon real events. But knowledge and design could be improved also without accidents. Control room operators and maintenance staff can provide invaluable knowledge and methods; to improve causal

Preserving and sharing tacit knowledge in a nuclear power plant

International Nuclear Information System (INIS)

Kuronen, T.; Saeaemaenen, K.; Jaervenpaeae, E.; Rintala, N.

2007-01-01

Tacit knowledge of nuclear experts is essential for reliable and competent performance of nuclear power plants. This report discusses preserving and sharing tacit knowledge in nuclear power plant context. Tacit knowledge as well as its structure and content in this complex and safety-critical context are described, and the role of tacit knowledge in expertise is discussed. In order to contribute to tacit knowledge preserving the challenges in and prerequisites for tacit knowledge sharing are identified. In addition, based on empirical case studies and literature, good practices and methods for tacit knowledge sharing are described. The report is based on the results of DIAMOND research project conducted in 2004-2006 in Finnish nuclear power plants, tacit knowledge, nuclear power plant, tacit knowledge sharing methods, expertise. (author abstract)

The Underdetermined Knowledge-Based Theory of the MNC

DEFF Research Database (Denmark)

Fransson, Anders; Håkanson, Lars; W. Liesch, Peter

2011-01-01

In this note we revisit two core propositions of the knowledge-based view of the firm found in the seminal work of Kogut and Zander: (1) that multinational corporations (MNCs) exist because transfers and re-combinations of knowledge occur more efficiently inside MNCs than between MNCs and third...... parties; and (2) that the threat of opportunism is not necessary, although it may be sufficient, to explain the existence of the MNC. Their knowledge-based view shifted the conceptualization of the firm from an institution arising from market failure and transaction costs economizing to a progeny......-combination of knowledge among their members. Important insights may be gained by applying the concept of epistemic communities implicit in the knowledge-based perspective beyond firm-level hierarchies....

Knowledge-based scheduling of arrival aircraft

Science.gov (United States)

Krzeczowski, K.; Davis, T.; Erzberger, H.; Lev-Ram, I.; Bergh, C.

1995-01-01

A knowledge-based method for scheduling arrival aircraft in the terminal area has been implemented and tested in real-time simulation. The scheduling system automatically sequences, assigns landing times, and assigns runways to arrival aircraft by utilizing continuous updates of aircraft radar data and controller inputs. The scheduling algorithms is driven by a knowledge base which was obtained in over two thousand hours of controller-in-the-loop real-time simulation. The knowledge base contains a series of hierarchical 'rules' and decision logic that examines both performance criteria, such as delay reduction, as well as workload reduction criteria, such as conflict avoidance. The objective of the algorithms is to devise an efficient plan to land the aircraft in a manner acceptable to the air traffic controllers. This paper will describe the scheduling algorithms, give examples of their use, and present data regarding their potential benefits to the air traffic system.

Nuclear Energy -- Knowledge Base for Advanced Modeling and Simulation (NE-KAMS) Code Verification and Validation Data Standards and Requirements: Fluid Dynamics Version 1.0

Energy Technology Data Exchange (ETDEWEB)

Greg Weirs; Hyung Lee

2011-09-01

V&V and UQ are the primary means to assess the accuracy and reliability of M&S and, hence, to establish confidence in M&S. Though other industries are establishing standards and requirements for the performance of V&V and UQ, at present, the nuclear industry has not established such standards or requirements. However, the nuclear industry is beginning to recognize that such standards are needed and that the resources needed to support V&V and UQ will be very significant. In fact, no single organization has sufficient resources or expertise required to organize, conduct and maintain a comprehensive V&V and UQ program. What is needed is a systematic and standardized approach to establish and provide V&V and UQ resources at a national or even international level, with a consortium of partners from government, academia and industry. Specifically, what is needed is a structured and cost-effective knowledge base that collects, evaluates and stores verification and validation data, and shows how it can be used to perform V&V and UQ, leveraging collaboration and sharing of resources to support existing engineering and licensing procedures as well as science-based V&V and UQ processes. The Nuclear Energy Knowledge base for Advanced Modeling and Simulation (NE-KAMS) is being developed at the Idaho National Laboratory in conjunction with Bettis Laboratory, Sandia National Laboratories, Argonne National Laboratory, Utah State University and others with the objective of establishing a comprehensive and web-accessible knowledge base to provide V&V and UQ resources for M&S for nuclear reactor design, analysis and licensing. The knowledge base will serve as an important resource for technical exchange and collaboration that will enable credible and reliable computational models and simulations for application to nuclear power. NE-KAMS will serve as a valuable resource for the nuclear industry, academia, the national laboratories, the U.S. Nuclear Regulatory Commission (NRC) and

Knowledge base rule partitioning design for CLIPS

Science.gov (United States)

Mainardi, Joseph D.; Szatkowski, G. P.

1990-01-01

This describes a knowledge base (KB) partitioning approach to solve the problem of real-time performance using the CLIPS AI shell when containing large numbers of rules and facts. This work is funded under the joint USAF/NASA Advanced Launch System (ALS) Program as applied research in expert systems to perform vehicle checkout for real-time controller and diagnostic monitoring tasks. The Expert System advanced development project (ADP-2302) main objective is to provide robust systems responding to new data frames of 0.1 to 1.0 second intervals. The intelligent system control must be performed within the specified real-time window, in order to meet the demands of the given application. Partitioning the KB reduces the complexity of the inferencing Rete net at any given time. This reduced complexity improves performance but without undo impacts during load and unload cycles. The second objective is to produce highly reliable intelligent systems. This requires simple and automated approaches to the KB verification & validation task. Partitioning the KB reduces rule interaction complexity overall. Reduced interaction simplifies the V&V testing necessary by focusing attention only on individual areas of interest. Many systems require a robustness that involves a large number of rules, most of which are mutually exclusive under different phases or conditions. The ideal solution is to control the knowledge base by loading rules that directly apply for that condition, while stripping out all rules and facts that are not used during that cycle. The practical approach is to cluster rules and facts into associated 'blocks'. A simple approach has been designed to control the addition and deletion of 'blocks' of rules and facts, while allowing real-time operations to run freely. Timing tests for real-time performance for specific machines under R/T operating systems have not been completed but are planned as part of the analysis process to validate the design.

Assessing segment- and corridor-based travel-time reliability on urban freeways : final report.

Science.gov (United States)

2016-09-01

Travel time and its reliability are intuitive performance measures for freeway traffic operations. The objective of this project was to quantify segment-based and corridor-based travel time reliability measures on urban freeways. To achieve this obje...

Development of diagnosis and maintenance support system for nuclear power plants with flexible inference function and knowledge base edition support function

International Nuclear Information System (INIS)

Fujii, Makoto; Seki, Eiji; Tai, Ichiro; Morioka, Toshihiko

1988-01-01

For the reliable and efficient diagnosis and inspection work of the nuclear power plant equipments, 'Diagnosis and Maintenance Support System' has been developed. This system has functions to assist operators or engineers to observe and evaluate equipment conditions based on the experts' knowledge. These functions are carried out through dialogue between the system and users. This system has two subsystems: diagnosis subsystem and knowledge base edition support subsystem. To achieve the functions of diagnosis subsystem, a new method of knowledge processing for equipment diagnosis is adopted. This method is based on the concept of 'Cause Generation and Checking'. Knowledge for diagnosis is represented with modularized production rules. And each rule module consists of four different type rules with hierarchical structure. With this approach, the system is equipped with sufficient performance not only in diagnosis function but also in flexible man-machine interface. Knowledge base edition support subsystem (Graphical Rule Editor) is provided for this system. This editor has functions to display and edit the contents of knowledge base with tree structures through the graphic display. With these functions, the efficiency of constructing expert system is highly improved. By applying this system to the maintenance support of neutron monitoring system, it is proved that this system has satisfactory performance as a diagnosis and maintenance support system. (author)

Conceptual Pathway Querying of Natural Logic Knowledge Bases from Text Bases

DEFF Research Database (Denmark)

Andreasen, Troels; Bulskov, Henrik; Nilsson, Jørgen Fischer

2013-01-01

language than predicate logic. Natural logic accommodates a variety of scientific parlance, ontologies and domain models. It also supports a semantic net or graph view of the knowledge base. This admits computation of relationships between concepts simultaneously through pathfinding in the knowledge base...

Risk based knowledge assessments: towards a toolbox for managing key knowledge assets

International Nuclear Information System (INIS)

Bright, Clive

2008-01-01

Full text: It is now well acknowledged that considerable Knowledge Management (KM) issues are faced by national and international nuclear communities. Much of these problems relate to issues of an ageing workforce and the significantly reduced influx of new generation of nuclear engineers and scientists. The management discipline of KM contains a broad spectrum of methods and techniques. However, the effective implementation of a KM strategy requires the selection and deployment of appropriate and targeted approaches that are pertinent to the particular issues of the technical or business area within an organisation. A clear strategy is contingent upon an assessment of what are the knowledge areas and what are the key (knowledge) risk areas. In particular the following issues have to be addressed: 'what knowledge exists?', 'what is the nature and format of that knowledge?' and 'what knowledge is key to our continued, safe, and effective operation?'. Answers to such questions will enable an organisation to prioritise KM effort and employ subsequent KM approaches that are appropriate. Subsequent approaches ranging from the utilisation of information technologies, such as databases; knowledge retention methods; and the setting up of Community of Practices to share knowledge and experience. This paper considers a risk assessment based approach to KM. In so doing the paper extends work previously reported on an approach to conducting knowledge audits by considering the integration of that approach with approaches to (knowledge) risk assessment. The paper also provides a brief review of the various KM approaches that can act to reduce the level of risk faced by an organisation. The paper concludes by reflecting upon the role, value of deploying such a risk based approach. (author)

THE DESIGN OF KNOWLEDGE BASE FOR SURFACE RELATIONS BASED PART RECOGNITION APPROACH

Directory of Open Access Journals (Sweden)

Adem ÇİÇEK

2007-01-01

Full Text Available In this study, a new knowledge base for an expert system used in part recognition algorithm has been designed. Parts are recognized by the computer program by comparing face adjacency relations and attributes belonging to each part represented in the rules in the knowledge base developed with face adjacency relations and attributes generated from STEP file of the part. Besides, rule writing process has been quite simplified by generating the rules represented in the knowledge base with an automatic rule writing module developed within the system. With the knowledge base and automatic rule writing module used in the part recognition system, simple, intermediate and complex parts can be recognized by a part recognition program.

Nuclear reactions video (knowledge base on low energy nuclear physics)

International Nuclear Information System (INIS)

Zagrebaev, V.; Kozhin, A.

1999-01-01

The NRV (nuclear reactions video) is an open and permanently extended global system of management and graphical representation of nuclear data and video-graphic computer simulation of low energy nuclear dynamics. It consists of a complete and renewed nuclear database and well known theoretical models of low energy nuclear reactions altogether forming the 'low energy nuclear knowledge base'. The NRV solves two main problems: 1) fast and visualized obtaining and processing experimental data on nuclear structure and nuclear reactions; 2) possibility for any inexperienced user to analyze experimental data within reliable commonly used models of nuclear dynamics. The system is based on the realization of the following principal things: the net and code compatibility with the main existing nuclear databases; maximal simplicity in handling: extended menu, friendly graphical interface, hypertext description of the models, and so on; maximal visualization of input data, dynamics of studied processes and final results by means of real three-dimensional images, plots, tables and formulas and a three-dimensional animation. All the codes are composed as the real Windows applications and work under Windows 95/NT

Knowledge-based methods for control systems

International Nuclear Information System (INIS)

Larsson, J.E.

1992-01-01

This thesis consists of three projects which combine artificial intelligence and control. The first part describes an expert system interface for system identification, using the interactive identification program Idpac. The interface works as an intelligent help system, using the command spy strategy. It contains a multitude of help system ideas. The concept of scripts is introduced as a data structure used to describe the procedural part of the knowledge in the interface. Production rules are used to represent diagnostic knowledge. A small knowledge database of scripts and rules has been developed and an example run is shown. The second part describes an expert system for frequency response analysis. This is one of the oldest and most widely used methods to determine the dynamics of a stable linear system. Though quite simple, it requires knowledge and experience of the user, in order to produce reliable results. The expert system is designed to help the user in performing the analysis. It checks whether the system is linear, finds the frequency and amplitude ranges, verifies the results, and, if errors should occur, tries to give explanation and remedies for them. The third part describes three diagnostic methods for use with industrial processes. They are measurement validation, i.e., consistency checking of sensor and measurement values using any redundancy of instrumentation; alarm analysis, i.e. analysis of multiple alarm situations to find which alarms are directly connected to primary faults and which alarms are consequential effects of the primary ones; and fault diagnosis, i.e., a search for the causes of and remedies for faults. The three methods use multilevel flow models, (MFM), to describe the target process. They have been implemented in the programming tool G2, and successfully tested on two small processes. (164 refs.) (au)

Managing Knowledge-Based Resource Capabilities Under Uncertainty

OpenAIRE

Janice E. Carrillo; Cheryl Gaimon

2004-01-01

A firm's ability to manage its knowledge-based resource capabilities has become increasingly important as a result of performance threats triggered by technology change and intense competition. At the manufacturing plant level, we focus on three repositories of knowledge that drive performance. First, the physical production or information systems represent knowledge embedded in the plant's technical systems. Second, the plant's workforce has knowledge, including diverse scientific informatio...

APPROACH ON INTELLIGENT OPTIMIZATION DESIGN BASED ON COMPOUND KNOWLEDGE

Institute of Scientific and Technical Information of China (English)

Yao Jianchu; Zhou Ji; Yu Jun

2003-01-01

A concept of an intelligent optimal design approach is proposed, which is organized by a kind of compound knowledge model. The compound knowledge consists of modularized quantitative knowledge, inclusive experience knowledge and case-based sample knowledge. By using this compound knowledge model, the abundant quantity information of mathematical programming and the symbolic knowledge of artificial intelligence can be united together in this model. The intelligent optimal design model based on such a compound knowledge and the automatically generated decomposition principles based on it are also presented. Practically, it is applied to the production planning, process schedule and optimization of production process of a refining & chemical work and a great profit is achieved. Specially, the methods and principles are adaptable not only to continuous process industry, but also to discrete manufacturing one.

Method for analysis and assessment of the relation between stress and reliability of knowledge-based actions in the probabilistic safety analysis; Methode fuer die Analyse und Bewertung der Wechselwirkung zwischen Stress und der Zuverlaessigkeit wissensbasierten Handelns in der probabilistischen Sicherheitsanalyse

Energy Technology Data Exchange (ETDEWEB)

Fassmann, Werner

2014-06-15

According to the current theoretical and empirical state-of-the-art, stress has to be understood as the emotional and cognitive reaction by which humans adapt to situations which imply real or imagined danger, threat, or frustration of important personal goals or needs. The emotional reaction to such situations can be so extreme that rational coping with the situation will be precluded. In less extreme cases, changes of cognitive processes underlying human action will occur, which may systematically affect the reliability of tasks personnel has to perform in a stressful situation. Reliable task performance by personnel of nuclear power plants and other risk technologies is also affected by such effects. The method developed in the frame of the research and development project RS1198 sponsored by the German Federal Ministry for Economic Affairs and Energy (BMWi) addresses both aspects of emotional and cognitive coping with stressful situations. Analytical and evaluation steps of the approach provide guidance to the end users on how to capture and quantify the contribution of stress-related emotional and cognitive factors to the reliable performance of knowledge-based actions. For this purpose, a suitable guideline has been developed. Further research for clarifying open questions has been identified. A case study application illustrates how to use the method. Part of the work performed in this project was dedicated to a review addressing the question to which extent Swain's approach to the analysis and evaluation of stress is in line with current scientific knowledge. Suitable suggestions for updates have been developed.

HuRECA: Human Reliability Evaluator for Computer-based Control Room Actions

International Nuclear Information System (INIS)

Kim, Jae Whan; Lee, Seung Jun; Jang, Seung Cheol

2011-01-01

As computer-based design features such as computer-based procedures (CBP), soft controls (SCs), and integrated information systems are being adopted in main control rooms (MCR) of nuclear power plants, a human reliability analysis (HRA) method capable of dealing with the effects of these design features on human reliability is needed. From the observations of human factors engineering verification and validation experiments, we have drawn some major important characteristics on operator behaviors and design-related influencing factors (DIFs) from the perspective of human reliability. Firstly, there are new DIFs that should be considered in developing an HRA method for computer-based control rooms including especially CBP and SCs. In the case of the computer-based procedure rather than the paper-based procedure, the structural and managerial elements should be considered as important PSFs in addition to the procedural contents. In the case of the soft controllers, the so-called interface management tasks (or secondary tasks) should be reflected in the assessment of human error probability. Secondly, computer-based control rooms can provide more effective error recovery features than conventional control rooms. Major error recovery features for computer-based control rooms include the automatic logic checking function of the computer-based procedure and the information sharing feature of the general computer-based designs

Community-based health insurance knowledge, concern ...

African Journals Online (AJOL)

Community-based health insurance knowledge, concern, preferences, and financial planning for health care among informal sector workers in a health district of Douala, Cameroon. ... This is mainly due to the lack of awareness and limited knowledge on the basic concepts of a CBHI by this target population. Solidarity ...

Modeling and knowledge acquisition processes using case-based inference

Directory of Open Access Journals (Sweden)

Ameneh Khadivar

2017-03-01

Full Text Available The method of acquisition and presentation of the organizational Process Knowledge has considered by many KM researches. In this research a model for process knowledge acquisition and presentation has been presented by using the approach of Case Base Reasoning. The validation of the presented model was evaluated by conducting an expert panel. Then a software has been developed based on the presented model and implemented in Eghtesad Novin Bank of Iran. In this company, based on the stages of the presented model, first the knowledge intensive processes has been identified, then the Process Knowledge was stored in a knowledge base in the format of problem/solution/consequent .The retrieval of the knowledge was done based on the similarity of the nearest neighbor algorithm. For validating of the implemented system, results of the system has compared by the results of the decision making of the expert of the process.

Improving Phrap-based assembly of the rat using "reliable" overlaps.

Directory of Open Access Journals (Sweden)

Michael Roberts

2008-03-01

Full Text Available The assembly methods used for whole-genome shotgun (WGS data have a major impact on the quality of resulting draft genomes. We present a novel algorithm to generate a set of "reliable" overlaps based on identifying repeat k-mers. To demonstrate the benefits of using reliable overlaps, we have created a version of the Phrap assembly program that uses only overlaps from a specific list. We call this version PhrapUMD. Integrating PhrapUMD and our "reliable-overlap" algorithm with the Baylor College of Medicine assembler, Atlas, we assemble the BACs from the Rattus norvegicus genome project. Starting with the same data as the Nov. 2002 Atlas assembly, we compare our results and the Atlas assembly to the 4.3 Mb of rat sequence in the 21 BACs that have been finished. Our version of the draft assembly of the 21 BACs increases the coverage of finished sequence from 93.4% to 96.3%, while simultaneously reducing the base error rate from 4.5 to 1.1 errors per 10,000 bases. There are a number of ways of assessing the relative merits of assemblies when the finished sequence is available. If one views the overall quality of an assembly as proportional to the inverse of the product of the error rate and sequence missed, then the assembly presented here is seven times better. The UMD Overlapper with options for reliable overlaps is available from the authors at http://www.genome.umd.edu. We also provide the changes to the Phrap source code enabling it to use only the reliable overlaps.

Comparison of clinical knowledge bases for summarization of electronic health records.

Science.gov (United States)

McCoy, Allison B; Sittig, Dean F; Wright, Adam

2013-01-01

Automated summarization tools that create condition-specific displays may improve clinician efficiency. These tools require new kinds of knowledge that is difficult to obtain. We compared five problem-medication pair knowledge bases generated using four previously described knowledge base development approaches. The number of pairs in the resulting mapped knowledge bases varied widely due to differing mapping techniques from the source terminologies, ranging from 2,873 to 63,977,738 pairs. The number of overlapping pairs across knowledge bases was low, with one knowledge base having half of the pairs overlapping with another knowledge base, and most having less than a third overlapping. Further research is necessary to better evaluate the knowledge bases independently in additional settings, and to identify methods to integrate the knowledge bases.

An accurate and efficient reliability-based design optimization using the second order reliability method and improved stability transformation method

Science.gov (United States)

Meng, Zeng; Yang, Dixiong; Zhou, Huanlin; Yu, Bo

2018-05-01

The first order reliability method has been extensively adopted for reliability-based design optimization (RBDO), but it shows inaccuracy in calculating the failure probability with highly nonlinear performance functions. Thus, the second order reliability method is required to evaluate the reliability accurately. However, its application for RBDO is quite challenge owing to the expensive computational cost incurred by the repeated reliability evaluation and Hessian calculation of probabilistic constraints. In this article, a new improved stability transformation method is proposed to search the most probable point efficiently, and the Hessian matrix is calculated by the symmetric rank-one update. The computational capability of the proposed method is illustrated and compared to the existing RBDO approaches through three mathematical and two engineering examples. The comparison results indicate that the proposed method is very efficient and accurate, providing an alternative tool for RBDO of engineering structures.

In defense of types in knowledge-based CAAD

DEFF Research Database (Denmark)

Galle, Per

1997-01-01

There are two basic approaches to representation of design knowledge in knowledge-based CAAD systems, the type-based approach which has a long tradition, and the more recent typeless approach. Proponents of the latter have offered a number of arguments against the type-based approach which...

Reliability and risk analysis data base development: an historical perspective

International Nuclear Information System (INIS)

Fragola, Joseph R.

1996-01-01

Collection of empirical data and data base development for use in the prediction of the probability of future events has a long history. Dating back at least to the 17th century, safe passage events and mortality events were collected and analyzed to uncover prospective underlying classes and associated class attributes. Tabulations of these developed classes and associated attributes formed the underwriting basis for the fledgling insurance industry. Much earlier, master masons and architects used design rules of thumb to capture the experience of the ages and thereby produce structures of incredible longevity and reliability (Antona, E., Fragola, J. and Galvagni, R. Risk based decision analysis in design. Fourth SRA Europe Conference Proceedings, Rome, Italy, 18-20 October 1993). These rules served so well in producing robust designs that it was not until almost the 19th century that the analysis (Charlton, T.M., A History Of Theory Of Structures In The 19th Century, Cambridge University Press, Cambridge, UK, 1982) of masonry voussoir arches, begun by Galileo some two centuries earlier (Galilei, G. Discorsi e dimostrazioni mathematiche intorno a due nuove science, (Discourses and mathematical demonstrations concerning two new sciences, Leiden, The Netherlands, 1638), was placed on a sound scientific basis. Still, with the introduction of new materials (such as wrought iron and steel) and the lack of theoretical knowledge and computational facilities, approximate methods of structural design abounded well into the second half of the 20th century. To this day structural designers account for material variations and gaps in theoretical knowledge by employing factors of safety (Benvenuto, E., An Introduction to the History of Structural Mechanics, Part II: Vaulted Structures and Elastic Systems, Springer-Verlag, NY, 1991) or codes of practice (ASME Boiler and Pressure Vessel Code, ASME, New York) originally developed in the 19th century (Antona, E., Fragola, J. and

Knowledge Governance Strategies in Project-based Organizations

DEFF Research Database (Denmark)

Pemsel, Sofia; Müller, Ralf; Söderlund, Jonas

2016-01-01

Knowledge governance (KG) aims at strategically influencing knowledge processes by implementing governance mechanisms. Little is known about whether, how, or why such strategies differ among firms. We utilize a large-scale empirical study of 20 organizations to develop a typology of KG strategies...... in project-based organizations; we then explore how these strategies emerge and affect organizational knowledge processes. Six strategies are identified: Protector, Deliverer, Polisher, Explorer, Supporter, and Analyzer. This paper posits a multi-level categorization model to facilitate comparisons among KG...... strategies. We uncover three main drivers of organizations' chosen knowledge governance strategies-namely, attitudes about humans, knowledge, and knowledge control....

Multidisciplinary Inverse Reliability Analysis Based on Collaborative Optimization with Combination of Linear Approximations

Directory of Open Access Journals (Sweden)

Xin-Jia Meng

2015-01-01

Full Text Available Multidisciplinary reliability is an important part of the reliability-based multidisciplinary design optimization (RBMDO. However, it usually has a considerable amount of calculation. The purpose of this paper is to improve the computational efficiency of multidisciplinary inverse reliability analysis. A multidisciplinary inverse reliability analysis method based on collaborative optimization with combination of linear approximations (CLA-CO is proposed in this paper. In the proposed method, the multidisciplinary reliability assessment problem is first transformed into a problem of most probable failure point (MPP search of inverse reliability, and then the process of searching for MPP of multidisciplinary inverse reliability is performed based on the framework of CLA-CO. This method improves the MPP searching process through two elements. One is treating the discipline analyses as the equality constraints in the subsystem optimization, and the other is using linear approximations corresponding to subsystem responses as the replacement of the consistency equality constraint in system optimization. With these two elements, the proposed method realizes the parallel analysis of each discipline, and it also has a higher computational efficiency. Additionally, there are no difficulties in applying the proposed method to problems with nonnormal distribution variables. One mathematical test problem and an electronic packaging problem are used to demonstrate the effectiveness of the proposed method.

Automated knowledge acquisition for second generation knowledge base systems: A conceptual analysis and taxonomy

Energy Technology Data Exchange (ETDEWEB)

Williams, K.E.; Kotnour, T.

1991-01-01

In this paper, we present a conceptual analysis of knowledge-base development methodologies. The purpose of this research is to help overcome the high cost and lack of efficiency in developing knowledge base representations for artificial intelligence applications. To accomplish this purpose, we analyzed the available methodologies and developed a knowledge-base development methodology taxonomy. We review manual, machine-aided, and machine-learning methodologies. A set of developed characteristics allows description and comparison among the methodologies. We present the results of this conceptual analysis of methodologies and recommendations for development of more efficient and effective tools.

Automated knowledge acquisition for second generation knowledge base systems: A conceptual analysis and taxonomy

Energy Technology Data Exchange (ETDEWEB)

Williams, K.E.; Kotnour, T.

1991-12-31

In this paper, we present a conceptual analysis of knowledge-base development methodologies. The purpose of this research is to help overcome the high cost and lack of efficiency in developing knowledge base representations for artificial intelligence applications. To accomplish this purpose, we analyzed the available methodologies and developed a knowledge-base development methodology taxonomy. We review manual, machine-aided, and machine-learning methodologies. A set of developed characteristics allows description and comparison among the methodologies. We present the results of this conceptual analysis of methodologies and recommendations for development of more efficient and effective tools.

Reliability Evaluation of Bridges Based on Nonprobabilistic Response Surface Limit Method

Directory of Open Access Journals (Sweden)

Xuyong Chen

2017-01-01

Full Text Available Due to many uncertainties in nonprobabilistic reliability assessment of bridges, the limit state function is generally unknown. The traditional nonprobabilistic response surface method is a lengthy and oscillating iteration process and leads to difficultly solving the nonprobabilistic reliability index. This article proposes a nonprobabilistic response surface limit method based on the interval model. The intention of this method is to solve the upper and lower limits of the nonprobabilistic reliability index and to narrow the range of the nonprobabilistic reliability index. If the range of the reliability index reduces to an acceptable accuracy, the solution will be considered convergent, and the nonprobabilistic reliability index will be obtained. The case study indicates that using the proposed method can avoid oscillating iteration process, make iteration process stable and convergent, reduce iteration steps significantly, and improve computational efficiency and precision significantly compared with the traditional nonprobabilistic response surface method. Finally, the nonprobabilistic reliability evaluation process of bridge will be built through evaluating the reliability of one PC continuous rigid frame bridge with three spans using the proposed method, which appears to be more simple and reliable when lack of samples and parameters in the bridge nonprobabilistic reliability evaluation is present.

Information modelling and knowledge bases XXV

CERN Document Server

Tokuda, T; Jaakkola, H; Yoshida, N

2014-01-01

Because of our ever increasing use of and reliance on technology and information systems, information modelling and knowledge bases continue to be important topics in those academic communities concerned with data handling and computer science. As the information itself becomes more complex, so do the levels of abstraction and the databases themselves. This book is part of the series Information Modelling and Knowledge Bases, which concentrates on a variety of themes in the important domains of conceptual modeling, design and specification of information systems, multimedia information modelin

Gradient-based reliability maps for ACM-based segmentation of hippocampus.

Science.gov (United States)

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.

The effect of knowledge based view on sustainable competitive advantage

Directory of Open Access Journals (Sweden)

Fatemeh Rezaee

2015-11-01

Full Text Available This study investigates the quantitative relationship between knowledge based view (i.e. empowering employees, promoting confidence, coding rules and sustainability competitive advantage (i.e. market, customer, financial within the banking industry of Iran. A valid research instrument was utilized to conduct a survey of 150 top- and middle-level managers from Mellat bank of Iran. With a response rate of 81.3 percent, 122 questionnaires are returned; the number of valid and usable questionnaires was 101. In order to determine validity of questionnaire, the content validity was used and Cronbach's alpha was used to determine the reliability of the questionnaire (KBV questionnaire 0.886, SCA questionnaire 0.843. Utilizing the structural equation modeling, and after a series of exploratory and confirmatory factor analyses, it was found that KBV had the greatest effect on the market centered SCA, while it had the least influence on the customer centered.

Feasibility, reliability, and validity of a smartphone based application for the assessment of cognitive function in the elderly.

Directory of Open Access Journals (Sweden)

Robert M Brouillette

Full Text Available While considerable knowledge has been gained through the use of established cognitive and motor assessment tools, there is a considerable interest and need for the development of a battery of reliable and validated assessment tools that provide real-time and remote analysis of cognitive and motor function in the elderly. Smartphones appear to be an obvious choice for the development of these "next-generation" assessment tools for geriatric research, although to date no studies have reported on the use of smartphone-based applications for the study of cognition in the elderly. The primary focus of the current study was to assess the feasibility, reliability, and validity of a smartphone-based application for the assessment of cognitive function in the elderly. A total of 57 non-demented elderly individuals were administered a newly developed smartphone application-based Color-Shape Test (CST in order to determine its utility in measuring cognitive processing speed in the elderly. Validity of this novel cognitive task was assessed by correlating performance on the CST with scores on widely accepted assessments of cognitive function. Scores on the CST were significantly correlated with global cognition (Mini-Mental State Exam: r = 0.515, p<0.0001 and multiple measures of processing speed and attention (Digit Span: r = 0.427, p<0.0001; Trail Making Test: r = -0.651, p<0.00001; Digit Symbol Test: r = 0.508, p<0.0001. The CST was not correlated with naming and verbal fluency tasks (Boston Naming Test, Vegetable/Animal Naming or memory tasks (Logical Memory Test. Test re-test reliability was observed to be significant (r = 0.726; p = 0.02. Together, these data are the first to demonstrate the feasibility, reliability, and validity of using a smartphone-based application for the purpose of assessing cognitive function in the elderly. The importance of these findings for the establishment of smartphone-based assessment batteries

Enhancing reliable online transaction with intelligent rule-based ...

African Journals Online (AJOL)

Enhancing reliable online transaction with intelligent rule-based fraud detection technique. ... These are with a bid to reducing amongst other things the cost of production and also dissuade the poor handling of Nigeria currency. The CBN pronouncement has necessitated the upsurge in transactions completed with credit ...

From conventional software based systems to knowledge based systems

International Nuclear Information System (INIS)

Bologna, S.

1995-01-01

Even if todays nuclear power plants have a very good safety record, there is a continuous search for still improving safety. One direction of this effort address operational safety, trying to improve the handling of disturbances and accidents partly by further automation, partly by creating a better control room environment, providing the operator with intelligent support systems to help in the decision making process. Introduction of intelligent computerised operator support systems has proved to be an efficient way of improving the operators performance. A number of systems have been developed worldwide, assisting in tasks like process fault detection and diagnosis, selection and implementation of proper remedial actions. Unfortunately, the use of Knowledge Based Systems (KBSs), introduces a new dimension to the problem of the licensing process. KBSs, despite the different technology employed, are still nothing more than a computer program. Unfortunately, quite a few people building knowledge based systems seem to ignore the many good programming practices that have evolved over the years for producing traditional computer programs. In this paper the author will try to point out similarities and differences between conventional software based systems, and knowledge based systems, introducing also the concept of model based reasoning. (orig.) (25 refs., 2 figs.)

Semantics-based plausible reasoning to extend the knowledge coverage of medical knowledge bases for improved clinical decision support

OpenAIRE

Mohammadhassanzadeh, Hossein; Van Woensel, William; Abidi, Samina Raza; Abidi, Syed Sibte Raza

2017-01-01

Background Capturing complete medical knowledge is challenging-often due to incomplete patient Electronic Health Records (EHR), but also because of valuable, tacit medical knowledge hidden away in physicians? experiences. To extend the coverage of incomplete medical knowledge-based systems beyond their deductive closure, and thus enhance their decision-support capabilities, we argue that innovative, multi-strategy reasoning approaches should be applied. In particular, plausible reasoning mech...

Knowledge-Based Approaches: Two cases of applicability

DEFF Research Database (Denmark)

Andersen, Tom

1997-01-01

Basic issues of the term: A knowledge-based approach (KBA) are discussed. Two cases of applicable to KBA are presented, and its concluded that KBA is more than just IT.......Basic issues of the term: A knowledge-based approach (KBA) are discussed. Two cases of applicable to KBA are presented, and its concluded that KBA is more than just IT....

Reliability analysis of offshore structures using OMA based fatigue stresses

DEFF Research Database (Denmark)

Silva Nabuco, Bruna; Aissani, Amina; Glindtvad Tarpø, Marius

2017-01-01

focus is on the uncertainty observed on the different stresses used to predict the damage. This uncertainty can be reduced by Modal Based Fatigue Monitoring which is a technique based on continuously measuring of the accelerations in few points of the structure with the use of accelerometers known...... points of the structure, the stress history can be calculated in any arbitrary point of the structure. The accuracy of the estimated actual stress is analyzed by experimental tests on a scale model where the obtained stresses are compared to strain gauges measurements. After evaluating the fatigue...... stresses directly from the operational response of the structure, a reliability analysis is performed in order to estimate the reliability of using Modal Based Fatigue Monitoring for long term fatigue studies....

Knowledge-based computer security advisor

International Nuclear Information System (INIS)

Hunteman, W.J.; Squire, M.B.

1991-01-01

The rapid expansion of computer security information and technology has included little support to help the security officer identify the safeguards needed to comply with a policy and to secure a computing system. This paper reports that Los Alamos is developing a knowledge-based computer security system to provide expert knowledge to the security officer. This system includes a model for expressing the complex requirements in computer security policy statements. The model is part of an expert system that allows a security officer to describe a computer system and then determine compliance with the policy. The model contains a generic representation that contains network relationships among the policy concepts to support inferencing based on information represented in the generic policy description

Automated extraction of knowledge for model-based diagnostics

Science.gov (United States)

Gonzalez, Avelino J.; Myler, Harley R.; Towhidnejad, Massood; Mckenzie, Frederic D.; Kladke, Robin R.

1990-01-01

The concept of accessing computer aided design (CAD) design databases and extracting a process model automatically is investigated as a possible source for the generation of knowledge bases for model-based reasoning systems. The resulting system, referred to as automated knowledge generation (AKG), uses an object-oriented programming structure and constraint techniques as well as internal database of component descriptions to generate a frame-based structure that describes the model. The procedure has been designed to be general enough to be easily coupled to CAD systems that feature a database capable of providing label and connectivity data from the drawn system. The AKG system is capable of defining knowledge bases in formats required by various model-based reasoning tools.

Knowledge based management of technical specifications

International Nuclear Information System (INIS)

Fiedler, U.; Schalm, S.; Pranckeviciute, K.

1992-01-01

TechSPEX is a knowledge based advisory system for checking the status of a nuclear plant on compliance with the safety limits and the limiting conditions of operation. These prescripts for safe reactor operation exist as textual information. For the purpose of its operational use an explicit representation formalism is introduced. On this basis, various approaches of text retrieval are realized, condition based surveillance and control is supported too. Knowledge editing and verification modules ease the adaption to changing requirements. TechSPEX has been implemented in PROLOG. (author). 6 refs, 3 figs

Feasibility, reliability, and validity of a smartphone based application for the assessment of cognitive function in the elderly.

Science.gov (United States)

Brouillette, Robert M; Foil, Heather; Fontenot, Stephanie; Correro, Anthony; Allen, Ray; Martin, Corby K; Bruce-Keller, Annadora J; Keller, Jeffrey N

2013-01-01

While considerable knowledge has been gained through the use of established cognitive and motor assessment tools, there is a considerable interest and need for the development of a battery of reliable and validated assessment tools that provide real-time and remote analysis of cognitive and motor function in the elderly. Smartphones appear to be an obvious choice for the development of these "next-generation" assessment tools for geriatric research, although to date no studies have reported on the use of smartphone-based applications for the study of cognition in the elderly. The primary focus of the current study was to assess the feasibility, reliability, and validity of a smartphone-based application for the assessment of cognitive function in the elderly. A total of 57 non-demented elderly individuals were administered a newly developed smartphone application-based Color-Shape Test (CST) in order to determine its utility in measuring cognitive processing speed in the elderly. Validity of this novel cognitive task was assessed by correlating performance on the CST with scores on widely accepted assessments of cognitive function. Scores on the CST were significantly correlated with global cognition (Mini-Mental State Exam: r = 0.515, psmartphone-based application for the purpose of assessing cognitive function in the elderly. The importance of these findings for the establishment of smartphone-based assessment batteries of cognitive and motor function in the elderly is discussed.

A knowledge-based operator advisor system for integration of fault detection, control, and diagnosis to enhance the safe and reliable operation of nuclear power plants

International Nuclear Information System (INIS)

Bhatnagar, R.

1989-01-01

A Knowledged-Based Operator Advisor System has been developed for enhancing the complex task of maintaining safe and reliable operation of nuclear power plants. The operator's activities have been organized into the four tasks of data interpretation for abstracting high level information from sensor data, plant state monitoring for identification of faults, plan execution for controlling the faults, and diagnosis for determination of root causes of faults. The Operator Advisor System is capable of identifying the abnormal functioning of the plant in terms of: (1) deviations from normality, (2) pre-enumerated abnormal events, and (3) safety threats. The classification of abnormal functioning into the three categories of deviations from normality, abnormal events, and safety threats allows the detection of faults at three levels of: (1) developing faults, (2) developed faults, and (3) safety threatening faults. After the identification of abnormal functioning the system will identify the procedures to be executed to mitigate the consequences of abnormal functioning and will help the operator by displaying the procedure steps and monitoring the success of actions taken. The system also is capable of diagnosing the root causes of abnormal functioning. The identification, and diagnosis of root causes of abnormal functioning are done in parallel to the task of procedure execution, allowing the detection of more critical safety threats while executing procedures to control abnormal events

Knowledge-based operator guidance system for Japanese PWRs

International Nuclear Information System (INIS)

Fujita, Y.; Ito, K.; Kawanago, S.; Tani, M.; Murata, R.

1986-01-01

A knowledge-based operator support system for nuclear power plant operation is under development. The main theme of the study is the incorporation of operator's cognitive structure as the framework of the knowledge representation and inference control mechanisms. Based upon information collected from interviews, and experiments using a real-time simulator, an operator's model related to diagnostic tasks was developed. A knowledge-based system incorporating the proposed model demonstrated highly efficient problem solving capabilities and the dynamic fitness to operator's perceptual feeling, thereby suggesting the potential importance and practical benefit of such a study

FROM TRADITIONAL ACCOUNTING TO KNOWLEDGE BASED ACCOUNTING ORGANIZATIONS

Directory of Open Access Journals (Sweden)

NICOLETA RADNEANTU

2010-01-01

Full Text Available Nowadays, we may observe that the rules of traditional economy have changed. The new economy – the knowledge based economy determine also major change in organizations resources, structure, strategic objectives, departments, accounting, goods. In our research we want to underline how the accounting rules, regulations and paradigms have changed to cope with political, economic and social challenges, as well as to the emergence of knowledge based organization. We also try to find out where Romanian accounting is on the hard road of evolution from traditional to knowledge based.

Improved Reliability-Based Optimization with Support Vector Machines and Its Application in Aircraft Wing Design

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Yu Wang

2015-01-01

Full Text Available A new reliability-based design optimization (RBDO method based on support vector machines (SVM and the Most Probable Point (MPP is proposed in this work. SVM is used to create a surrogate model of the limit-state function at the MPP with the gradient information in the reliability analysis. This guarantees that the surrogate model not only passes through the MPP but also is tangent to the limit-state function at the MPP. Then, importance sampling (IS is used to calculate the probability of failure based on the surrogate model. This treatment significantly improves the accuracy of reliability analysis. For RBDO, the Sequential Optimization and Reliability Assessment (SORA is employed as well, which decouples deterministic optimization from the reliability analysis. The improved SVM-based reliability analysis is used to amend the error from linear approximation for limit-state function in SORA. A mathematical example and a simplified aircraft wing design demonstrate that the improved SVM-based reliability analysis is more accurate than FORM and needs less training points than the Monte Carlo simulation and that the proposed optimization strategy is efficient.

Assessment of Iranian nurses and emergency medical personnel in terms of cardiopulmonary resuscitation knowledge based on the 2010 guideline

Directory of Open Access Journals (Sweden)

Reza Pourmirza Kalhori

2017-01-01

Full Text Available Background: The aim of this study was to compare the cardiopulmonary resuscitation (CPR knowledge of hospital nurses and emergency medical personnel in Kermanshah, Iran. Materials and Methods: This descriptive cross-sectional study was conducted on 330 hospital nurses and 159 emergency medical personnel working in educational hospitals and emergency medical centers in Kermanshah. Data were collected using a validated and reliable (r = 0.74 researcher-made questionnaire consisting of a demographic characteristics questionnaire and the 2010 CPR knowledge questionnaire. Results: Based on the most recent CPR guidelines, the knowledge of 19.5%, 78.6%, and 1.9% of the emergency medical staff was excellent, good, and moderate, respectively. None of the participants had poor knowledge. In addition, the knowledge of 20.2%, 65.4%, 14%, and 0.4% of the nurses in this study was excellent, good, moderate, and poor, respectively. There was no significant difference in CPR knowledge between hospital nurses and emergency medical staff. Moreover, no significant association was found between CPR knowledge and gender, age, work experience, field of study, previous occupation, and advanced resuscitation courses. However, CPR knowledge of individuals with training in basic CPR courses was higher than participants without training in these courses (P < 0.05. Conclusions: Based on the findings of this study, CPR knowledge among Iranian nurses and emergency medical personnel was in an acceptable range. Nevertheless, it is strongly recommended that nurses and emergency staff receive training according to the most recent CPR guidelines.

A Bayesian belief nets based quantitative software reliability assessment for PSA: COTS case study

International Nuclear Information System (INIS)

Eom, H. S.; Sung, T. Y.; Jeong, H. S.; Park, J. H.; Kang, H. G.; Lee, K. Y.; Park, J. K

2002-03-01

Current reliability assessments of safety critical software embedded in the digital systems in nuclear power plants are based on the rule-based qualitative assessment methods. Then recently practical needs require the quantitative features of software reliability for Probabilistic Safety Assessment (PSA) that is one of important methods being used in assessing the whole safety of nuclear power plant. But conventional quantitative software reliability assessment methods are not enough to get the necessary results in assessing the safety critical software used in nuclear power plants. Thus, current reliability assessment methods for these digital systems exclude the software part or use arbitrary values for the software reliability in the assessment. This reports discusses a Bayesian Belief Nets (BBN) based quantification method that models current qualitative software assessment in formal way and produces quantitative results required for PSA. Commercial Off-The-Shelf (COTS) software dedication process that KAERI developed was applied to the discussed BBN based method for evaluating the plausibility of the proposed method in PSA

Reliability estimation of safety-critical software-based systems using Bayesian networks

International Nuclear Information System (INIS)

Helminen, A.

2001-06-01

Due to the nature of software faults and the way they cause system failures new methods are needed for the safety and reliability evaluation of software-based safety-critical automation systems in nuclear power plants. In the research project 'Programmable automation system safety integrity assessment (PASSI)', belonging to the Finnish Nuclear Safety Research Programme (FINNUS, 1999-2002), various safety assessment methods and tools for software based systems are developed and evaluated. The project is financed together by the Radiation and Nuclear Safety Authority (STUK), the Ministry of Trade and Industry (KTM) and the Technical Research Centre of Finland (VTT). In this report the applicability of Bayesian networks to the reliability estimation of software-based systems is studied. The applicability is evaluated by building Bayesian network models for the systems of interest and performing simulations for these models. In the simulations hypothetical evidence is used for defining the parameter relations and for determining the ability to compensate disparate evidence in the models. Based on the experiences from modelling and simulations we are able to conclude that Bayesian networks provide a good method for the reliability estimation of software-based systems. (orig.)

Reliability-Based Structural Optimization of Wave Energy Converters

Directory of Open Access Journals (Sweden)

Simon Ambühl

2014-12-01

Full Text Available More and more wave energy converter (WEC concepts are reaching prototypelevel. Once the prototype level is reached, the next step in order to further decrease thelevelized cost of energy (LCOE is optimizing the overall system with a focus on structuraland maintenance (inspection costs, as well as on the harvested power from the waves.The target of a fully-developed WEC technology is not maximizing its power output,but minimizing the resulting LCOE. This paper presents a methodology to optimize thestructural design of WECs based on a reliability-based optimization problem and the intentto maximize the investor’s benefits by maximizing the difference between income (e.g., fromselling electricity and the expected expenses (e.g., structural building costs or failure costs.Furthermore, different development levels, like prototype or commercial devices, may havedifferent main objectives and will be located at different locations, as well as receive varioussubsidies. These points should be accounted for when performing structural optimizationsof WECs. An illustrative example on the gravity-based foundation of the Wavestar deviceis performed showing how structural design can be optimized taking target reliability levelsand different structural failure modes due to extreme loads into account.

A methodology for strain-based fatigue reliability analysis

International Nuclear Information System (INIS)

Zhao, Y.X.

2000-01-01

A significant scatter of the cyclic stress-strain (CSS) responses should be noted for a nuclear reactor material, 1Cr18Ni9Ti pipe-weld metal. Existence of the scatter implies that a random cyclic strain applied history will be introduced under any of the loading modes even a deterministic loading history. A non-conservative evaluation might be given in the practice without considering the scatter. A methodology for strain-based fatigue reliability analysis, which has taken into account the scatter, is developed. The responses are approximately modeled by probability-based CSS curves of Ramberg-Osgood relation. The strain-life data are modeled, similarly, by probability-based strain-life curves of Coffin-Manson law. The reliability assessment is constructed by considering interference of the random fatigue strain applied and capacity histories. Probability density functions of the applied and capacity histories are analytically given. The methodology could be conveniently extrapolated to the case of deterministic CSS relation as the existent methods did. Non-conservative evaluation of the deterministic CSS relation and availability of present methodology have been indicated by an analysis of the material test results

Knowledge based expert system approach to instrumentation selection (INSEL

Directory of Open Access Journals (Sweden)

S. Barai

2004-08-01

Full Text Available The selection of appropriate instrumentation for any structural measurement of civil engineering structure is a complex task. Recent developments in Artificial Intelligence (AI can help in an organized use of experiential knowledge available on instrumentation for laboratory and in-situ measurement. Usually, the instrumentation decision is based on the experience and judgment of experimentalists. The heuristic knowledge available for different types of measurement is domain dependent and the information is scattered in varied knowledge sources. The knowledge engineering techniques can help in capturing the experiential knowledge. This paper demonstrates a prototype knowledge based system for INstrument SELection (INSEL assistant where the experiential knowledge for various structural domains can be captured and utilized for making instrumentation decision. In particular, this Knowledge Based Expert System (KBES encodes the heuristics on measurement and demonstrates the instrument selection process with reference to steel bridges. INSEL runs on a microcomputer and uses an INSIGHT 2+ environment.

Bridging the gap: simulations meet knowledge bases

Science.gov (United States)

King, Gary W.; Morrison, Clayton T.; Westbrook, David L.; Cohen, Paul R.

2003-09-01

Tapir and Krill are declarative languages for specifying actions and agents, respectively, that can be executed in simulation. As such, they bridge the gap between strictly declarative knowledge bases and strictly executable code. Tapir and Krill components can be combined to produce models of activity which can answer questions about mechanisms and processes using conventional inference methods and simulation. Tapir was used in DARPA's Rapid Knowledge Formation (RKF) project to construct models of military tactics from the Army Field Manual FM3-90. These were then used to build Courses of Actions (COAs) which could be critiqued by declarative reasoning or via Monte Carlo simulation. Tapir and Krill can be read and written by non-knowledge engineers making it an excellent vehicle for Subject Matter Experts to build and critique knowledge bases.

Reliability-based failure cause assessment of collapsed bridge during construction

International Nuclear Information System (INIS)

Choi, Hyun-Ho; Lee, Sang-Yoon; Choi, Il-Yoon; Cho, Hyo-Nam; Mahadevan, Sankaran

2006-01-01

Until now, in many forensic reports, the failure cause assessments are usually carried out by a deterministic approach so far. However, it may be possible for the forensic investigation to lead to unreasonable results far from the real collapse scenario, because the deterministic approach does not systematically take into account any information on the uncertainties involved in the failures of structures. Reliability-based failure cause assessment (reliability-based forensic engineering) methodology is developed which can incorporate the uncertainties involved in structural failures and structures, and to apply them to the collapsed bridge in order to identify the most critical failure scenario and find the cause that triggered the bridge collapse. Moreover, to save the time and cost of evaluation, an algorithm of automated event tree analysis (ETA) is proposed and possible to automatically calculate the failure probabilities of the failure events and the occurrence probabilities of failure scenarios. Also, for reliability analysis, uncertainties are estimated more reasonably by using the Bayesian approach based on the experimental laboratory testing data in the forensic report. For the applicability, the proposed approach is applied to the Hang-ju Grand Bridge, which collapsed during construction, and compared with deterministic approach

Technical requirements on knowledge base and instrumentation system for decision making in plant operation and maintenance

International Nuclear Information System (INIS)

Kitamura, Masaharu; Yoshikawa, Shinji; Hasegawa, Makoto

1998-03-01

A series of technical surveys and studies are described in this report to examine and identify technical requirements to be posed on knowledge base and instrumentation system as the fundamental in high reliability computational decision making in operation and maintenance of nuclear power plants. Monitoring and diagnosis are focused as the important tasks among the operation/maintenance-related tasks. A concrete monitoring and diagnosis system configuration has been proposed consisting of distributed symptom database and of on-demand measurement subsystem. An prototype of the proposed system configuration has been successfully verified. (author)

Media Consumption and Creation in Attitudes Toward and Knowledge of Inflammatory Bowel Disease: Web-Based Survey

Science.gov (United States)

Basil, Miles; Guo, Ling; Parker Ward, Sarah; Farraye, Francis A; Reich, Jason

2017-01-01

Background Inflammatory bowel disease (IBD) is a chronic gastrointestinal condition affecting over 5 million people globally and 1.6 million in the United States but currently lacks a precisely determined cause or cure. The range of symptoms IBD patients experience are often debilitating, and the societal stigmas associated with some such symptoms can further degrade their quality of life. Better understanding the nature of this public reproach then is a critical component for improving awareness campaigns and, ultimately, the experiences of IBD patients. Objective The objective of this study was to explore and assess the public’s awareness and knowledge of IBD, as well as what relationship, if any, exists between the social stigma surrounding IBD, knowledge of the disease, and various media usage, including social media. Methods Utilizing a Web-based opt-in platform, we surveyed a nationally representative sample (n=1200) with demographics mirroring those of the US Census figures across baseline parameters. Using constructed indices based on factor analysis, we were able to build reliable measures of personal characteristics, media behaviors, and perceptions and knowledge of IBD. Results Among the American public, IBD is the most stigmatized of seven diseases, including genital herpes and human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Additionally, IBD knowledge is generally low with 11.08% (133/1200) of the sample indicating no familiarity with the disease and 85.50% (1026/1200) of participants inaccurately answering two-thirds of the IBD index questions with which their knowledge was assessed. Increased knowledge of IBD is associated with lower levels of stigma. However, social media use is currently related to lower levels of IBD knowledge (Pcommunication solutions. PMID:29222081

Monte Carlo simulation based reliability evaluation in a multi-bilateral contracts market

International Nuclear Information System (INIS)

Goel, L.; Viswanath, P.A.; Wang, P.

2004-01-01

This paper presents a time sequential Monte Carlo simulation technique to evaluate customer load point reliability in multi-bilateral contracts market. The effects of bilateral transactions, reserve agreements, and the priority commitments of generating companies on customer load point reliability have been investigated. A generating company with bilateral contracts is modelled as an equivalent time varying multi-state generation (ETMG). A procedure to determine load point reliability based on ETMG has been developed. The developed procedure is applied to a reliability test system to illustrate the technique. Representing each bilateral contract by an ETMG provides flexibility in determining the reliability at various customer load points. (authors)

Multi-state reliability for coolant pump based on dependent competitive failure model

International Nuclear Information System (INIS)

Shang Yanlong; Cai Qi; Zhao Xinwen; Chen Ling

2013-01-01

By taking into account the effect of degradation due to internal vibration and external shocks. and based on service environment and degradation mechanism of nuclear power plant coolant pump, a multi-state reliability model of coolant pump was proposed for the system that involves competitive failure process between shocks and degradation. Using this model, degradation state probability and system reliability were obtained under the consideration of internal vibration and external shocks for the degraded coolant pump. It provided an effective method to reliability analysis for coolant pump in nuclear power plant based on operating environment. The results can provide a decision making basis for design changing and maintenance optimization. (authors)

A competency based selection procedure for Dutch postgraduate GP training: a pilot study on validity and reliability.

Science.gov (United States)

Vermeulen, Margit I; Tromp, Fred; Zuithoff, Nicolaas P A; Pieters, Ron H M; Damoiseaux, Roger A M J; Kuyvenhoven, Marijke M

2014-12-01

Abstract Background: Historically, semi-structured interviews (SSI) have been the core of the Dutch selection for postgraduate general practice (GP) training. This paper describes a pilot study on a newly designed competency-based selection procedure that assesses whether candidates have the competencies that are required to complete GP training. The objective was to explore reliability and validity aspects of the instruments developed. The new selection procedure comprising the National GP Knowledge Test (LHK), a situational judgement tests (SJT), a patterned behaviour descriptive interview (PBDI) and a simulated encounter (SIM) was piloted alongside the current procedure. Forty-seven candidates volunteered in both procedures. Admission decision was based on the results of the current procedure. Study participants did hardly differ from the other candidates. The mean scores of the candidates on the LHK and SJT were 21.9 % (SD 8.7) and 83.8% (SD 3.1), respectively. The mean self-reported competency scores (PBDI) were higher than the observed competencies (SIM): 3.7(SD 0.5) and 2.9(SD 0.6), respectively. Content-related competencies showed low correlations with one another when measured with different instruments, whereas more diverse competencies measured by a single instrument showed strong to moderate correlations. Moreover, a moderate correlation between LHK and SJT was found. The internal consistencies (intraclass correlation, ICC) of LHK and SJT were poor while the ICC of PBDI and SIM showed acceptable levels of reliability. Findings on content validity and reliability of these new instruments are promising to realize a competency based procedure. Further development of the instruments and research on predictive validity should be pursued.

Drug knowledge bases and their applications in biomedical informatics research.

Science.gov (United States)

Zhu, Yongjun; Elemento, Olivier; Pathak, Jyotishman; Wang, Fei

2018-01-03

Recent advances in biomedical research have generated a large volume of drug-related data. To effectively handle this flood of data, many initiatives have been taken to help researchers make good use of them. As the results of these initiatives, many drug knowledge bases have been constructed. They range from simple ones with specific focuses to comprehensive ones that contain information on almost every aspect of a drug. These curated drug knowledge bases have made significant contributions to the development of efficient and effective health information technologies for better health-care service delivery. Understanding and comparing existing drug knowledge bases and how they are applied in various biomedical studies will help us recognize the state of the art and design better knowledge bases in the future. In addition, researchers can get insights on novel applications of the drug knowledge bases through a review of successful use cases. In this study, we provide a review of existing popular drug knowledge bases and their applications in drug-related studies. We discuss challenges in constructing and using drug knowledge bases as well as future research directions toward a better ecosystem of drug knowledge bases. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

reliability reliability

African Journals Online (AJOL)

eobe

Corresponding author, Tel: +234-703. RELIABILITY .... V , , given by the code of practice. However, checks must .... an optimization procedure over the failure domain F corresponding .... of Concrete Members based on Utility Theory,. Technical ...

Exponential Reliability Coefficient based Reputation Mechanism for isolating selfish nodes in MANETs

Directory of Open Access Journals (Sweden)

J. Sengathir

2015-07-01

Full Text Available In mobile ad hoc networks, cooperation among active mobile nodes is considered to play a vital role in reliable transmission of data. But, the selfish mobile nodes present in an ad hoc environment refuse to forward neighbouring nodes’ packet for conserving its own energy. This intentional selfish behaviour drastically reduces the degree of cooperation maintained between the mobile nodes. Hence, a need arises for devising an effective mechanism which incorporates both energy efficiency and reputation into account for mitigating selfish behaviour in MANETs. In this paper, we propose an Exponential Reliability Coefficient based reputation Mechanism (ERCRM which isolates the selfish nodes from the routing path based on Exponential Reliability Coefficient (ExRC. This reliability coefficient manipulated through exponential failure rate based on moving average method highlights the most recent past behaviour of the mobile nodes for quantifying its genuineness. From the simulation results, it is evident that, the proposed ERCRM approach outperforms the existing Packet Conservation Monitoring Algorithm (PCMA and Spilt Half Reliability Coefficient based Mathematical Model (SHRCM in terms of performance evaluation metrics such as packet delivery ratio, throughput, total overhead and control overhead. Further, this ERCRM mechanism has a successful rate of 28% in isolating the selfish nodes from the routing path. Furthermore, it also aids in framing the exponential threshold point of detection as 0.4, where a maximum number of selfish nodes are identified when compared to the existing models available in the literature.

GrandBase: generating actionable knowledge from Big Data

Directory of Open Access Journals (Sweden)

Xiu Susie Fang

2017-08-01

Full Text Available Purpose – This paper aims to propose a system for generating actionable knowledge from Big Data and use this system to construct a comprehensive knowledge base (KB, called GrandBase. Design/methodology/approach – In particular, this study extracts new predicates from four types of data sources, namely, Web texts, Document Object Model (DOM trees, existing KBs and query stream to augment the ontology of the existing KB (i.e. Freebase. In addition, a graph-based approach to conduct better truth discovery for multi-valued predicates is also proposed. Findings – Empirical studies demonstrate the effectiveness of the approaches presented in this study and the potential of GrandBase. The future research directions regarding GrandBase construction and extension has also been discussed. Originality/value – To revolutionize our modern society by using the wisdom of Big Data, considerable KBs have been constructed to feed the massive knowledge-driven applications with Resource Description Framework triples. The important challenges for KB construction include extracting information from large-scale, possibly conflicting and different-structured data sources (i.e. the knowledge extraction problem and reconciling the conflicts that reside in the sources (i.e. the truth discovery problem. Tremendous research efforts have been contributed on both problems. However, the existing KBs are far from being comprehensive and accurate: first, existing knowledge extraction systems retrieve data from limited types of Web sources; second, existing truth discovery approaches commonly assume each predicate has only one true value. In this paper, the focus is on the problem of generating actionable knowledge from Big Data. A system is proposed, which consists of two phases, namely, knowledge extraction and truth discovery, to construct a broader KB, called GrandBase.

Models, methods and software for distributed knowledge acquisition for the automated construction of integrated expert systems knowledge bases

International Nuclear Information System (INIS)

Dejneko, A.O.

2011-01-01

Based on an analysis of existing models, methods and means of acquiring knowledge, a base method of automated knowledge acquisition has been chosen. On the base of this method, a new approach to integrate information acquired from knowledge sources of different typologies has been proposed, and the concept of a distributed knowledge acquisition with the aim of computerized formation of the most complete and consistent models of problem areas has been introduced. An original algorithm for distributed knowledge acquisition from databases, based on the construction of binary decision trees has been developed [ru

Model-based explanation of plant knowledge

Energy Technology Data Exchange (ETDEWEB)

Huuskonen, P.J. [VTT Electronics, Oulu (Finland). Embedded Software

1997-12-31

This thesis deals with computer explanation of knowledge related to design and operation of industrial plants. The needs for explanation are motivated through case studies and literature reviews. A general framework for analysing plant explanations is presented. Prototypes demonstrate key mechanisms for implementing parts of the framework. Power plants, steel mills, paper factories, and high energy physics control systems are studied to set requirements for explanation. The main problems are seen to be either lack or abundance of information. Design knowledge in particular is found missing at plants. Support systems and automation should be enhanced with ways to explain plant knowledge to the plant staff. A framework is formulated for analysing explanations of plant knowledge. It consists of three parts: 1. a typology of explanation, organised by the class of knowledge (factual, functional, or strategic) and by the target of explanation (processes, automation, or support systems), 2. an identification of explanation tasks generic for the plant domain, and 3. an identification of essential model types for explanation (structural, behavioural, functional, and teleological). The tasks use the models to create the explanations of the given classes. Key mechanisms are discussed to implement the generic explanation tasks. Knowledge representations based on objects and their relations form a vocabulary to model and present plant knowledge. A particular class of models, means-end models, are used to explain plant knowledge. Explanations are generated through searches in the models. Hypertext is adopted to communicate explanations over dialogue based on context. The results are demonstrated in prototypes. The VICE prototype explains the reasoning of an expert system for diagnosis of rotating machines at power plants. The Justifier prototype explains design knowledge obtained from an object-oriented plant design tool. Enhanced access mechanisms into on-line documentation are

Model-based explanation of plant knowledge

Energy Technology Data Exchange (ETDEWEB)

Huuskonen, P J [VTT Electronics, Oulu (Finland). Embedded Software

1998-12-31

This thesis deals with computer explanation of knowledge related to design and operation of industrial plants. The needs for explanation are motivated through case studies and literature reviews. A general framework for analysing plant explanations is presented. Prototypes demonstrate key mechanisms for implementing parts of the framework. Power plants, steel mills, paper factories, and high energy physics control systems are studied to set requirements for explanation. The main problems are seen to be either lack or abundance of information. Design knowledge in particular is found missing at plants. Support systems and automation should be enhanced with ways to explain plant knowledge to the plant staff. A framework is formulated for analysing explanations of plant knowledge. It consists of three parts: 1. a typology of explanation, organised by the class of knowledge (factual, functional, or strategic) and by the target of explanation (processes, automation, or support systems), 2. an identification of explanation tasks generic for the plant domain, and 3. an identification of essential model types for explanation (structural, behavioural, functional, and teleological). The tasks use the models to create the explanations of the given classes. Key mechanisms are discussed to implement the generic explanation tasks. Knowledge representations based on objects and their relations form a vocabulary to model and present plant knowledge. A particular class of models, means-end models, are used to explain plant knowledge. Explanations are generated through searches in the models. Hypertext is adopted to communicate explanations over dialogue based on context. The results are demonstrated in prototypes. The VICE prototype explains the reasoning of an expert system for diagnosis of rotating machines at power plants. The Justifier prototype explains design knowledge obtained from an object-oriented plant design tool. Enhanced access mechanisms into on-line documentation are

Transition to knowledge-based economy in Saudi Arabia

NARCIS (Netherlands)

Nour, S.

2014-01-01

This paper discusses the progress in transition to knowledge-based economy in Saudi Arabia. As for the methodology, this paper uses updated secondary data obtained from different sources. It uses both descriptive and comparative approaches and uses the OECD definition of knowledge-based economy and

A knowledge based operator support system for emergency conditions in nuclear power plants

International Nuclear Information System (INIS)

Venkatesh Babu, C.; Subramanium, K.

1992-01-01

The control centres of the operating Indian nuclear power plants contain a large number of indicators and controls spread over many panels. In the event of onset of an emergency condition, there results a profusion of information, both numeric and symbolic. The operator may succumb to an information and cognitive overload that may be compounded by a lack of knowledge. The failure to apply knowledge and reasoning to solve an operational problem can lead to human error, which has been a major contributing factor in nuclear accidents. From the viewpoint of Artificial Intelligence, human error occurs if the operational problem requires computing resources that exceed human capabilities. The application of Artificial Intelligence, particularly expert systems, to nuclear power plant control room activities has considerable potential to reduce operator error and improve safety and reliability. The purpose of this paper is to discuss an investigative study of the feasibility of developing an operator support system incorporating Artificial Intelligence techniques. An information processing model of such a system, herein designated as Knowledge Based Operator Support System - KBOSS, employing expert systems technology, has been developed. The features of this system are described, and issues involved in its development are discussed. (author). 2 refs., 5 figs., 1 tab

Reliability and relative validity of a child nutrition questionnaire to simultaneously assess dietary patterns associated with positive energy balance and food behaviours, attitudes, knowledge and environments associated with healthy eating

Directory of Open Access Journals (Sweden)

Magarey Anthea M

2008-01-01

Full Text Available Abstract Background Food behaviours, attitudes, environments and knowledge are relevant to professionals in childhood obesity prevention, as are dietary patterns which promote positive energy balance. There is a lack of valid and reliable tools to measure these parameters. The aim of this study was to determine the reliability and relative validity of a child nutrition questionnaire assessing all of these parameters, used in the evaluation of a community-based childhood obesity prevention project. Methods The development of the 14-item questionnaire was informed by the aims of the obesity prevention project. A sub-sample of children aged 10–12 years from primary schools involved in the intervention was recruited at the project's baseline data collection (Test 1. Questionnaires were readministered (Test 2 following which students completed a 7-day food diary designed to reflect the questionnaire. Twelve scores were derived to assess consumption of fruit, vegetables, water, noncore foods and sweetened beverages plus food knowledge, behaviours, attitudes and environments. Reliability was assessed using (a the intra class correlation coefficient (ICC and 95% confidence intervals to compare scores from Tests 1 and 2 (test-retest reliability and (b Cronbach's alpha (internal consistency. Validity was assessed with Spearman correlations, bias and limits of agreement between scores from Test 1 and the 7-day diaries. The Wilcoxon signed rank test checked for significant differences between mean scores. Results One hundred and forty one students consented to the study. Test 2 (n = 134 occurred between eight and 36 days after Test 1. For 10/12 scores ICCs ranged from 0.47–0.66 (p 0.05 for 10/12 (test-retest reliability and 3/7 (validity scores. Conclusion This child nutrition questionnaire is a valid and reliable tool to simultaneously assess dietary patterns associated with positive energy balance, and food behaviours, attitudes and environments in

Knowledge Base Applications to Adaptive Space-Time Processing, Volume 5: Knowledge-Based Tracker Rule Book

National Research Council Canada - National Science Library

Morgan, Charles

2001-01-01

... processing algorithm can be applied. The proactive knowledge-based tracker uses information from other sources such as digital terrain maps, radar clutter and interference maps, and target priority assessments to determine the nature...

A Research Roadmap for Computation-Based Human Reliability Analysis

Energy Technology Data Exchange (ETDEWEB)

Boring, Ronald [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mandelli, Diego [Idaho National Lab. (INL), Idaho Falls, ID (United States); Joe, Jeffrey [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smith, Curtis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Groth, Katrina [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-08-01

The United States (U.S.) Department of Energy (DOE) is sponsoring research through the Light Water Reactor Sustainability (LWRS) program to extend the life of the currently operating fleet of commercial nuclear power plants. The Risk Informed Safety Margin Characterization (RISMC) research pathway within LWRS looks at ways to maintain and improve the safety margins of these plants. The RISMC pathway includes significant developments in the area of thermalhydraulics code modeling and the development of tools to facilitate dynamic probabilistic risk assessment (PRA). PRA is primarily concerned with the risk of hardware systems at the plant; yet, hardware reliability is often secondary in overall risk significance to human errors that can trigger or compound undesirable events at the plant. This report highlights ongoing efforts to develop a computation-based approach to human reliability analysis (HRA). This computation-based approach differs from existing static and dynamic HRA approaches in that it: (i) interfaces with a dynamic computation engine that includes a full scope plant model, and (ii) interfaces with a PRA software toolset. The computation-based HRA approach presented in this report is called the Human Unimodels for Nuclear Technology to Enhance Reliability (HUNTER) and incorporates in a hybrid fashion elements of existing HRA methods to interface with new computational tools developed under the RISMC pathway. The goal of this research effort is to model human performance more accurately than existing approaches, thereby minimizing modeling uncertainty found in current plant risk models.

A Research Roadmap for Computation-Based Human Reliability Analysis

International Nuclear Information System (INIS)

Boring, Ronald; Mandelli, Diego; Joe, Jeffrey; Smith, Curtis; Groth, Katrina

2015-01-01

The United States (U.S.) Department of Energy (DOE) is sponsoring research through the Light Water Reactor Sustainability (LWRS) program to extend the life of the currently operating fleet of commercial nuclear power plants. The Risk Informed Safety Margin Characterization (RISMC) research pathway within LWRS looks at ways to maintain and improve the safety margins of these plants. The RISMC pathway includes significant developments in the area of thermalhydraulics code modeling and the development of tools to facilitate dynamic probabilistic risk assessment (PRA). PRA is primarily concerned with the risk of hardware systems at the plant; yet, hardware reliability is often secondary in overall risk significance to human errors that can trigger or compound undesirable events at the plant. This report highlights ongoing efforts to develop a computation-based approach to human reliability analysis (HRA). This computation-based approach differs from existing static and dynamic HRA approaches in that it: (i) interfaces with a dynamic computation engine that includes a full scope plant model, and (ii) interfaces with a PRA software toolset. The computation-based HRA approach presented in this report is called the Human Unimodels for Nuclear Technology to Enhance Reliability (HUNTER) and incorporates in a hybrid fashion elements of existing HRA methods to interface with new computational tools developed under the RISMC pathway. The goal of this research effort is to model human performance more accurately than existing approaches, thereby minimizing modeling uncertainty found in current plant risk models.

The research on construction and application of machining process knowledge base

Science.gov (United States)

Zhao, Tan; Qiao, Lihong; Qie, Yifan; Guo, Kai

2018-03-01

In order to realize the application of knowledge in machining process design, from the perspective of knowledge in the application of computer aided process planning(CAPP), a hierarchical structure of knowledge classification is established according to the characteristics of mechanical engineering field. The expression of machining process knowledge is structured by means of production rules and the object-oriented methods. Three kinds of knowledge base models are constructed according to the representation of machining process knowledge. In this paper, the definition and classification of machining process knowledge, knowledge model, and the application flow of the process design based on the knowledge base are given, and the main steps of the design decision of the machine tool are carried out as an application by using the knowledge base.

Methodology for reliability allocation based on fault tree analysis and dualistic contrast

Institute of Scientific and Technical Information of China (English)

TONG Lili; CAO Xuewu

2008-01-01

Reliability allocation is a difficult multi-objective optimization problem.This paper presents a methodology for reliability allocation that can be applied to determine the reliability characteristics of reactor systems or subsystems.The dualistic contrast,known as one of the most powerful tools for optimization problems,is applied to the reliability allocation model of a typical system in this article.And the fault tree analysis,deemed to be one of the effective methods of reliability analysis,is also adopted.Thus a failure rate allocation model based on the fault tree analysis and dualistic contrast is achieved.An application on the emergency diesel generator in the nuclear power plant is given to illustrate the proposed method.

Enhancing acronym/abbreviation knowledge bases with semantic information.

Science.gov (United States)

Torii, Manabu; Liu, Hongfang

2007-10-11

In the biomedical domain, a terminology knowledge base that associates acronyms/abbreviations (denoted as SFs) with the definitions (denoted as LFs) is highly needed. For the construction such terminology knowledge base, we investigate the feasibility to build a system automatically assigning semantic categories to LFs extracted from text. Given a collection of pairs (SF,LF) derived from text, we i) assess the coverage of LFs and pairs (SF,LF) in the UMLS and justify the need of a semantic category assignment system; and ii) automatically derive name phrases annotated with semantic category and construct a system using machine learning. Utilizing ADAM, an existing collection of (SF,LF) pairs extracted from MEDLINE, our system achieved an f-measure of 87% when assigning eight UMLS-based semantic groups to LFs. The system has been incorporated into a web interface which integrates SF knowledge from multiple SF knowledge bases. Web site: http://gauss.dbb.georgetown.edu/liblab/SFThesurus.

Reliability and Availability of Cloud Computing

CERN Document Server

Bauer, Eric

2012-01-01

A holistic approach to service reliability and availability of cloud computing Reliability and Availability of Cloud Computing provides IS/IT system and solution architects, developers, and engineers with the knowledge needed to assess the impact of virtualization and cloud computing on service reliability and availability. It reveals how to select the most appropriate design for reliability diligence to assure that user expectations are met. Organized in three parts (basics, risk analysis, and recommendations), this resource is accessible to readers of diverse backgrounds and experience le

Reliability-based inspection of prestressed concrete containment structures

International Nuclear Information System (INIS)

Pandey, M.D.

1996-03-01

A study was undertaken to develop a reliability-based approach to the planning of inspection programs for prestressed concrete containment structures. The main function of the prestressing system is to ensure the leak integrity of the containment by maintaining a compressive state of stress under the tensile forces which arise in a hypothesized loss of coolant accident. Prestressing force losses (due to creep and shrinkage, stress relaxation or tendon corrosion) can lead to tensile stresses under accident pressure, resulting in loss of containment leak integrity due to concrete cracking and tensile yielding of the non-prestressed reinforcement. Therefore, the evaluation of prestressing inspection programs was based on their effectiveness in maintaining an acceptable reliability level with respect to a limit state representing yeilding of non-prestressed reinforcement. An annual target reliability of 10 -4 was used for this limit state. As specified in CSA-N287.7, the evaluation of prestressing systems for containment structures is based on the results of lift-off tests to determine the prestressing force. For unbonded systems the tests are carried out on a randomly selected sample from each tendon group in the structure. For bonded systems, the test is carried out on an unbonded test beam that matches the section geometry and material properties of the containment structure. It was found that flexural testing is useful in updating the probability of concrete cracking under accident pressure. For unbonded systems, the analysis indicated that the sample size recommended by the CSA Standard (4% of the tendon population) is adequate. The CSA recommendation for a five year inspection interval is conservative unless severe degradation of the prestressing system, characterized by a high prestressing loss rate (>3%) and a large coefficient of variation of the measured prestressing force (>15%), is observed

Structural design systems using knowledge-based techniques

International Nuclear Information System (INIS)

Orsborn, K.

1993-01-01

Engineering information management and the corresponding information systems are of a strategic importance for industrial enterprises. This thesis treats the interdisciplinary field of designing computing systems for structural design and analysis using knowledge-based techniques. Specific conceptual models have been designed for representing the structure and the process of objects and activities in a structural design and analysis domain. In this thesis, it is shown how domain knowledge can be structured along several classification principles in order to reduce complexity and increase flexibility. By increasing the conceptual level of the problem description and representation of the domain knowledge in a declarative form, it is possible to enhance the development, maintenance and use of software for mechanical engineering. This will result in a corresponding increase of the efficiency of the mechanical engineering design process. These ideas together with the rule-based control point out the leverage of declarative knowledge representation within this domain. Used appropriately, a declarative knowledge representation preserves information better, is more problem-oriented and change-tolerant than procedural representations. 74 refs

An adaptive neuro fuzzy model for estimating the reliability of component-based software systems

Directory of Open Access Journals (Sweden)

Kirti Tyagi

2014-01-01

Full Text Available Although many algorithms and techniques have been developed for estimating the reliability of component-based software systems (CBSSs, much more research is needed. Accurate estimation of the reliability of a CBSS is difficult because it depends on two factors: component reliability and glue code reliability. Moreover, reliability is a real-world phenomenon with many associated real-time problems. Soft computing techniques can help to solve problems whose solutions are uncertain or unpredictable. A number of soft computing approaches for estimating CBSS reliability have been proposed. These techniques learn from the past and capture existing patterns in data. The two basic elements of soft computing are neural networks and fuzzy logic. In this paper, we propose a model for estimating CBSS reliability, known as an adaptive neuro fuzzy inference system (ANFIS, that is based on these two basic elements of soft computing, and we compare its performance with that of a plain FIS (fuzzy inference system for different data sets.

Peer Evaluation Can Reliably Measure Local Knowledge

Science.gov (United States)

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…

Novel nonlinear knowledge-based mean force potentials based on machine learning.

Science.gov (United States)

Dong, Qiwen; Zhou, Shuigeng

2011-01-01

The prediction of 3D structures of proteins from amino acid sequences is one of the most challenging problems in molecular biology. An essential task for solving this problem with coarse-grained models is to deduce effective interaction potentials. The development and evaluation of new energy functions is critical to accurately modeling the properties of biological macromolecules. Knowledge-based mean force potentials are derived from statistical analysis of proteins of known structures. Current knowledge-based potentials are almost in the form of weighted linear sum of interaction pairs. In this study, a class of novel nonlinear knowledge-based mean force potentials is presented. The potential parameters are obtained by nonlinear classifiers, instead of relative frequencies of interaction pairs against a reference state or linear classifiers. The support vector machine is used to derive the potential parameters on data sets that contain both native structures and decoy structures. Five knowledge-based mean force Boltzmann-based or linear potentials are introduced and their corresponding nonlinear potentials are implemented. They are the DIH potential (single-body residue-level Boltzmann-based potential), the DFIRE-SCM potential (two-body residue-level Boltzmann-based potential), the FS potential (two-body atom-level Boltzmann-based potential), the HR potential (two-body residue-level linear potential), and the T32S3 potential (two-body atom-level linear potential). Experiments are performed on well-established decoy sets, including the LKF data set, the CASP7 data set, and the Decoys “R”Us data set. The evaluation metrics include the energy Z score and the ability of each potential to discriminate native structures from a set of decoy structures. Experimental results show that all nonlinear potentials significantly outperform the corresponding Boltzmann-based or linear potentials, and the proposed discriminative framework is effective in developing knowledge-based

The Ontology of Knowledge Based Optimization

OpenAIRE

Nasution, Mahyuddin K. M.

2012-01-01

Optimization has been becoming a central of studies in mathematic and has many areas with different applications. However, many themes of optimization came from different area have not ties closing to origin concepts. This paper is to address some variants of optimization problems using ontology in order to building basic of knowledge about optimization, and then using it to enhance strategy to achieve knowledge based optimization.

System safety and reliability using object-oriented programming techniques

International Nuclear Information System (INIS)

Patterson-Hine, F.A.; Koen, B.V.

1987-01-01

Direct evaluation fault tree codes have been written in recursive, list-processing computer languages such as PL/1 (PATREC-I) and LISP (PATREC-L). The pattern-matching strategy implemented in these codes has been used extensively in France to evaluate system reliability. Recent reviews of the risk management process suggest that a data base containing plant-specific information be integrated with a package of codes used for probabilistic risk assessment (PRA) to alleviate some of the difficulties that make a PRA so costly and time-intensive. A new programming paradigm, object-oriented programming, is uniquely suited for the development of such a software system. A knowledge base and fault tree evaluation algorithm, based on previous experience with PATREC-L, have been implemented using object-oriented techniques, resulting in a reliability assessment environment that is easy to develop, modify, and extend

Advanced software development workstation. Knowledge base design: Design of knowledge base for flight planning application

Science.gov (United States)

Izygon, Michel E.

1992-01-01

The development process of the knowledge base for the generation of Test Libraries for Mission Operations Computer (MOC) Command Support focused on a series of information gathering interviews. These knowledge capture sessions are supporting the development of a prototype for evaluating the capabilities of INTUIT on such an application. the prototype includes functions related to POCC (Payload Operation Control Center) processing. It prompts the end-users for input through a series of panels and then generates the Meds associated with the initialization and the update of hazardous command tables for a POCC Processing TLIB.

KBGIS-2: A knowledge-based geographic information system

Science.gov (United States)

Smith, T.; Peuquet, D.; Menon, S.; Agarwal, P.

1986-01-01

The architecture and working of a recently implemented knowledge-based geographic information system (KBGIS-2) that was designed to satisfy several general criteria for the geographic information system are described. The system has four major functions that include query-answering, learning, and editing. The main query finds constrained locations for spatial objects that are describable in a predicate-calculus based spatial objects language. The main search procedures include a family of constraint-satisfaction procedures that use a spatial object knowledge base to search efficiently for complex spatial objects in large, multilayered spatial data bases. These data bases are represented in quadtree form. The search strategy is designed to reduce the computational cost of search in the average case. The learning capabilities of the system include the addition of new locations of complex spatial objects to the knowledge base as queries are answered, and the ability to learn inductively definitions of new spatial objects from examples. The new definitions are added to the knowledge base by the system. The system is currently performing all its designated tasks successfully, although currently implemented on inadequate hardware. Future reports will detail the performance characteristics of the system, and various new extensions are planned in order to enhance the power of KBGIS-2.

Performance reliability prediction for thermal aging based on kalman filtering

International Nuclear Information System (INIS)

Ren Shuhong; Wen Zhenhua; Xue Fei; Zhao Wensheng

2015-01-01

The performance reliability of the nuclear power plant main pipeline that failed due to thermal aging was studied by the performance degradation theory. Firstly, through the data obtained from the accelerated thermal aging experiments, the degradation process of the impact strength and fracture toughness of austenitic stainless steel material of the main pipeline was analyzed. The time-varying performance degradation model based on the state space method was built, and the performance trends were predicted by using Kalman filtering. Then, the multi-parameter and real-time performance reliability prediction model for the main pipeline thermal aging was developed by considering the correlation between the impact properties and fracture toughness, and by using the stochastic process theory. Thus, the thermal aging performance reliability and reliability life of the main pipeline with multi-parameter were obtained, which provides the scientific basis for the optimization management of the aging maintenance decision making for nuclear power plant main pipelines. (authors)

Knowledge typology for imprecise probabilities.

Energy Technology Data Exchange (ETDEWEB)

Wilson, G. D. (Gregory D.); Zucker, L. J. (Lauren J.)

2002-01-01

When characterizing the reliability of a complex system there are often gaps in the data available for specific subsystems or other factors influencing total system reliability. At Los Alamos National Laboratory we employ ethnographic methods to elicit expert knowledge when traditional data is scarce. Typically, we elicit expert knowledge in probabilistic terms. This paper will explore how we might approach elicitation if methods other than probability (i.e., Dempster-Shafer, or fuzzy sets) prove more useful for quantifying certain types of expert knowledge. Specifically, we will consider if experts have different types of knowledge that may be better characterized in ways other than standard probability theory.

Final Report for the Virtual Reliability Realization System LDRD

Energy Technology Data Exchange (ETDEWEB)

DELLIN, THEODORE A.; HENDERSON, CHRISTOPHER L.; O' TOOLE, EDWARD J.

2000-12-01

Current approaches to reliability are not adequate to keep pace with the need for faster, better and cheaper products and systems. This is especially true in high consequence of failure applications. The original proposal for the LDRD was to look at this challenge and see if there was a new paradigm that could make reliability predictions, along with a quantitative estimate of the risk in that prediction, in a way that was faster, better and cheaper. Such an approach would be based on the underlying science models that are the backbone of reliability predictions. The new paradigm would be implemented in two software tools: the Virtual Reliability Realization System (VRRS) and the Reliability Expert System (REX). The three-year LDRD was funded at a reduced level for the first year ($120K vs. $250K) and not renewed. Because of the reduced funding, we concentrated on the initial development of the expertise system. We developed an interactive semiconductor calculation tool needed for reliability analyses. We also were able to generate a basic functional system using Microsoft Siteserver Commerce Edition and Microsoft Sequel Server. The base system has the capability to store Office documents from multiple authors, and has the ability to track and charge for usage. The full outline of the knowledge model has been incorporated as well as examples of various types of content.

Research on Control Method Based on Real-Time Operational Reliability Evaluation for Space Manipulator

Directory of Open Access Journals (Sweden)

Yifan Wang

2014-05-01

Full Text Available A control method based on real-time operational reliability evaluation for space manipulator is presented for improving the success rate of a manipulator during the execution of a task. In this paper, a method for quantitative analysis of operational reliability is given when manipulator is executing a specified task; then a control model which could control the quantitative operational reliability is built. First, the control process is described by using a state space equation. Second, process parameters are estimated in real time using Bayesian method. Third, the expression of the system's real-time operational reliability is deduced based on the state space equation and process parameters which are estimated using Bayesian method. Finally, a control variable regulation strategy which considers the cost of control is given based on the Theory of Statistical Process Control. It is shown via simulations that this method effectively improves the operational reliability of space manipulator control system.

Knowledge management: An abstraction of knowledge base and database management systems

Science.gov (United States)

Riedesel, Joel D.

1990-01-01

Artificial intelligence application requirements demand powerful representation capabilities as well as efficiency for real-time domains. Many tools exist, the most prevalent being expert systems tools such as ART, KEE, OPS5, and CLIPS. Other tools just emerging from the research environment are truth maintenance systems for representing non-monotonic knowledge, constraint systems, object oriented programming, and qualitative reasoning. Unfortunately, as many knowledge engineers have experienced, simply applying a tool to an application requires a large amount of effort to bend the application to fit. Much work goes into supporting work to make the tool integrate effectively. A Knowledge Management Design System (KNOMAD), is described which is a collection of tools built in layers. The layered architecture provides two major benefits; the ability to flexibly apply only those tools that are necessary for an application, and the ability to keep overhead, and thus inefficiency, to a minimum. KNOMAD is designed to manage many knowledge bases in a distributed environment providing maximum flexibility and expressivity to the knowledge engineer while also providing support for efficiency.

A study of operational and testing reliability in software reliability analysis

International Nuclear Information System (INIS)

Yang, B.; Xie, M.

2000-01-01

Software reliability is an important aspect of any complex equipment today. Software reliability is usually estimated based on reliability models such as nonhomogeneous Poisson process (NHPP) models. Software systems are improving in testing phase, while it normally does not change in operational phase. Depending on whether the reliability is to be predicted for testing phase or operation phase, different measure should be used. In this paper, two different reliability concepts, namely, the operational reliability and the testing reliability, are clarified and studied in detail. These concepts have been mixed up or even misused in some existing literature. Using different reliability concept will lead to different reliability values obtained and it will further lead to different reliability-based decisions made. The difference of the estimated reliabilities is studied and the effect on the optimal release time is investigated

Integration, Provenance, and Temporal Queries for Large-Scale Knowledge Bases

OpenAIRE

Gao, Shi

2016-01-01

Knowledge bases that summarize web information in RDF triples deliver many benefits, including support for natural language question answering and powerful structured queries that extract encyclopedic knowledge via SPARQL. Large scale knowledge bases grow rapidly in terms of scale and significance, and undergo frequent changes in both schema and content. Two critical problems have thus emerged: (i) how to support temporal queries that explore the history of knowledge bases or flash-back to th...

PROVIDING RELIABILITY OF HUMAN RESOURCES IN PRODUCTION MANAGEMENT PROCESS

Directory of Open Access Journals (Sweden)

Anna MAZUR

2014-07-01

Full Text Available People are the most valuable asset of an organization and the results of a company mostly depends on them. The human factor can also be a weak link in the company and cause of the high risk for many of the processes. Reliability of the human factor in the process of the manufacturing process will depend on many factors. The authors include aspects of human error, safety culture, knowledge, communication skills, teamwork and leadership role in the developed model of reliability of human resources in the management of the production process. Based on the case study and the results of research and observation of the author present risk areas defined in a specific manufacturing process and the results of evaluation of the reliability of human resources in the process.

Knowledge-based automated radiopharmaceutical manufacturing for Positron Emission Tomography

International Nuclear Information System (INIS)

Alexoff, D.L.

1991-01-01

This article describes the application of basic knowledge engineering principles to the design of automated synthesis equipment for radiopharmaceuticals used in Positron Emission Tomography (PET). Before discussing knowledge programming, an overview of the development of automated radiopharmaceutical synthesis systems for PET will be presented. Since knowledge systems will rely on information obtained from machine transducers, a discussion of the uses of sensory feedback in today's automated systems follows. Next, the operation of these automated systems is contrasted to radiotracer production carried out by chemists, and the rationale for and basic concepts of knowledge-based programming are explained. Finally, a prototype knowledge-based system supporting automated radiopharmaceutical manufacturing of 18FDG at Brookhaven National Laboratory (BNL) is described using 1stClass, a commercially available PC-based expert system shell

Ambulatory orthopaedic surgery patients' knowledge with internet-based education.

Science.gov (United States)

Heikkinen, Katja; Leino-Kilpi, H; Salanterä, S

2012-01-01

There is a growing need for patient education and an evaluation of its outcomes. The aim of this study was to compare ambulatory orthopaedic surgery patients' knowledge with Internet-based education and face-to-face education with a nurse. The following hypothesis was proposed: Internet-based patient education (experiment) is as effective as face-to-face education with a nurse (control) in increasing patients' level of knowledge and sufficiency of knowledge. In addition, the correlations of demographic variables were tested. The patients were randomized to either an experiment group (n = 72) or a control group (n = 75). Empirical data were collected with two instruments. Patients in both groups showed improvement in their knowledge during their care. Patients in the experiment group improved their knowledge level significantly more in total than those patients in the control group. There were no differences in patients' sufficiency of knowledge between the groups. Knowledge was correlated especially with patients' age, gender and earlier ambulatory surgeries. As a conclusion, positive results concerning patients' knowledge could be achieved with the Internet-based education. The Internet is a viable method in ambulatory care.

A PROCESS-BASED APPROACH TO KNOWLEDGE MANAGEMENT

OpenAIRE

Kovačić, Andrej; Bosilj Vukšić, Vesna; Lončar, Anita

2006-01-01

This paper analyses the relationship between business process modelling, knowledge management and information systems development projects. The paper’s main objective is to present business rules as the encoded knowledge of corporate business practices. Further, it introduces a rule-based business activity meta-model as a repository in which business knowledge can be captured and traced from their origin in the business environment through to their implementation in information systems. The c...

Reliability assessment based on subjective inferences

International Nuclear Information System (INIS)

Ma Zhibo; Zhu Jianshi; Xu Naixin

2003-01-01

The reliability information which comes from subjective analysis is often incomplete prior. This information can be generally assumed to exist in the form of either a stated prior mean of R (reliability) or a stated prior credibility interval on R. An efficient approach is developed to determine a complete beta prior distribution from the subjective information according to the principle of maximum entropy, and the the reliability of survival/failure product is assessed via Bayes theorem. Numerical examples are presented to illustrate the methods

Representability in DL-Lite_R knowledge base exchange

NARCIS (Netherlands)

Arenas, M.; Botoeva, E.; Calvanese, D.; Ryzhikov, V.; Sherkhonov, E.

2012-01-01

Knowledge base exchange can be considered as a generalization of data exchange in which the aim is to exchange between a source and a target connected through mappings, not only explicit knowledge, i.e., data, but also implicit knowledge in the form of axioms. Such problem has been investigated

Temporal reliability and lateralization of the resting-state language network.

Science.gov (United States)

Zhu, Linlin; Fan, Yang; Zou, Qihong; Wang, Jue; Gao, Jia-Hong; Niu, Zhendong

2014-01-01

The neural processing loop of language is complex but highly associated with Broca's and Wernicke's areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca's and Wernicke's areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca's area was found to be left lateralized, while the Wernicke's area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR) on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability.

Temporal reliability and lateralization of the resting-state language network.

Directory of Open Access Journals (Sweden)

Linlin Zhu

Full Text Available The neural processing loop of language is complex but highly associated with Broca's and Wernicke's areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca's and Wernicke's areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca's area was found to be left lateralized, while the Wernicke's area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability.

Temporal Reliability and Lateralization of the Resting-State Language Network

Science.gov (United States)

Zou, Qihong; Wang, Jue; Gao, Jia-Hong; Niu, Zhendong

2014-01-01

The neural processing loop of language is complex but highly associated with Broca's and Wernicke's areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca's and Wernicke's areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca's area was found to be left lateralized, while the Wernicke's area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR) on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability. PMID:24475058

Analysis of the relation between knowledge engineering and knowledge management based on the Nonaka and Takeuchi models

Directory of Open Access Journals (Sweden)

Christian Reyes

2007-07-01

Full Text Available The use of the Knowledge Management is fundamental in the creation of value within the companies, being at the present time a new form to obtain competitive advantages in specific market. Also, for the process of value creation is necessary to use specifics Information Technologies that they allow to reach the objectives drawn up when implementing a Knowledge Management project. In this sense, one of the more complete and efficient Information Technologies is the Knowledge Based System that as well comprises of the Knowledge Engineering. This article tries to analyze the existing relation between Knowledge Management, a specific model of knowledge creation, the Knowledge Based System and how this Information Technologies play a very important role in the creation, codification and transference of knowledge.

Multisite Reliability of MR-Based Functional Connectivity

Science.gov (United States)

Noble, Stephanie; Scheinost, Dustin; Finn, Emily S.; Shen, Xilin; Papademetris, Xenophon; McEwen, Sarah C.; Bearden, Carrie E.; Addington, Jean; Goodyear, Bradley; Cadenhead, Kristin S.; Mirzakhanian, Heline; Cornblatt, Barbara A.; Olvet, Doreen M.; Mathalon, Daniel H.; McGlashan, Thomas H.; Perkins, Diana O.; Belger, Aysenil; Seidman, Larry J.; Thermenos, Heidi; Tsuang, Ming T.; van Erp, Theo G.M.; Walker, Elaine F.; Hamann, Stephan; Woods, Scott W.; Cannon, Tyrone D.; Constable, R. Todd

2016-01-01

Recent years have witnessed an increasing number of multisite MRI functional connectivity (fcMRI) studies. While multisite studies are an efficient way to speed up data collection and increase sample sizes, especially for rare clinical populations, any effects of site or MRI scanner could ultimately limit power and weaken results. Little data exists on the stability of functional connectivity measurements across sites and sessions. In this study, we assess the influence of site and session on resting state functional connectivity measurements in a healthy cohort of traveling subjects (8 subjects scanned twice at each of 8 sites) scanned as part of the North American Prodrome Longitudinal Study (NAPLS). Reliability was investigated in three types of connectivity analyses: (1) seed-based connectivity with posterior cingulate cortex (PCC), right motor cortex (RMC), and left thalamus (LT) as seeds; (2) the intrinsic connectivity distribution (ICD), a voxel-wise connectivity measure; and (3) matrix connectivity, a whole-brain, atlas-based approach assessing connectivity between nodes. Contributions to variability in connectivity due to subject, site, and day-of-scan were quantified and used to assess between-session (test-retest) reliability in accordance with Generalizability Theory. Overall, no major site, scanner manufacturer, or day-of-scan effects were found for the univariate connectivity analyses; instead, subject effects dominated relative to the other measured factors. However, summaries of voxel-wise connectivity were found to be sensitive to site and scanner manufacturer effects. For all connectivity measures, although subject variance was three times the site variance, the residual represented 60–80% of the variance, indicating that connectivity differed greatly from scan to scan independent of any of the measured factors (i.e., subject, site, and day-of-scan). Thus, for a single 5 min scan, reliability across connectivity measures was poor (ICC=0.07–0

Translation and validation of the Malay version of the Stroke Knowledge Test.

Science.gov (United States)

Sowtali, Siti Noorkhairina; Yusoff, Dariah Mohd; Harith, Sakinah; Mohamed, Monniaty

2016-04-01

To date, there is a lack of published studies on assessment tools to evaluate the effectiveness of stroke education programs. This study developed and validated the Malay language version of the Stroke Knowledge Test research instrument. This study involved translation, validity, and reliability phases. The instrument underwent backward and forward translation of the English version into the Malay language. Nine experts reviewed the content for consistency, clarity, difficulty, and suitability for inclusion. Perceived usefulness and utilization were obtained from experts' opinions. Later, face validity assessment was conducted with 10 stroke patients to determine appropriateness of sentences and grammar used. A pilot study was conducted with 41 stroke patients to determine the item analysis and reliability of the translated instrument using the Kuder Richardson 20 or Cronbach's alpha. The final Malay version Stroke Knowledge Test included 20 items with good content coverage, acceptable item properties, and positive expert review ratings. Psychometric investigations suggest that Malay version Stroke Knowledge Test had moderate reliability with Kuder Richardson 20 or Cronbach's alpha of 0.58. Improvement is required for Stroke Knowledge Test items with unacceptable difficulty indices. Overall, the average rating of perceived usefulness and perceived utility of the instruments were both 72.7%, suggesting that reviewers were likely to use the instruments in their facilities. Malay version Stroke Knowledge Test was a valid and reliable tool to assess educational needs and to evaluate stroke knowledge among participants of group-based stroke education programs in Malaysia.

Maintenance management of railway infrastructures based on reliability analysis

International Nuclear Information System (INIS)

Macchi, Marco; Garetti, Marco; Centrone, Domenico; Fumagalli, Luca; Piero Pavirani, Gian

2012-01-01

Railway infrastructure maintenance plays a crucial role for rail transport. It aims at guaranteeing safety of operations and availability of railway tracks and related equipment for traffic regulation. Moreover, it is one major cost for rail transport operations. Thus, the increased competition in traffic market is asking for maintenance improvement, aiming at the reduction of maintenance expenditures while keeping the safety of operations. This issue is addressed by the methodology presented in the paper. The first step of the methodology consists of a family-based approach for the equipment reliability analysis; its purpose is the identification of families of railway items which can be given the same reliability targets. The second step builds the reliability model of the railway system for identifying the most critical items, given a required service level for the transportation system. The two methods have been implemented and tested in practical case studies, in the context of Rete Ferroviaria Italiana, the Italian public limited company for railway transportation.

Design Optimization Method for Composite Components Based on Moment Reliability-Sensitivity Criteria

Science.gov (United States)

Sun, Zhigang; Wang, Changxi; Niu, Xuming; Song, Yingdong

2017-08-01

In this paper, a Reliability-Sensitivity Based Design Optimization (RSBDO) methodology for the design of the ceramic matrix composites (CMCs) components has been proposed. A practical and efficient method for reliability analysis and sensitivity analysis of complex components with arbitrary distribution parameters are investigated by using the perturbation method, the respond surface method, the Edgeworth series and the sensitivity analysis approach. The RSBDO methodology is then established by incorporating sensitivity calculation model into RBDO methodology. Finally, the proposed RSBDO methodology is applied to the design of the CMCs components. By comparing with Monte Carlo simulation, the numerical results demonstrate that the proposed methodology provides an accurate, convergent and computationally efficient method for reliability-analysis based finite element modeling engineering practice.

Implementation of knowledge-based engineering methodology in hydraulic generator design

Directory of Open Access Journals (Sweden)

Wei Guo

2015-05-01

Full Text Available Hydraulic generator design companies are always being exhorted to become more competitive by reducing the lead time and costs for their products for survival. Knowledge-based engineering technology is a rapidly developing technology with competitive advantage for design application to reduce time and cost in product development. This article addresses the structure of the hydraulic generator design system based on the knowledge-based engineering technology in detail. The system operates by creating a unified knowledge base to store the scattered knowledge among the whole life of the design process, which was contained in the expert’s brain and technical literature. It helps designers to make appropriate decisions by supplying necessary information at the right time through query and inference engine to represent the knowledge within the knowledge-based engineering application framework. It also integrates the analysis tools into one platform to help achieve global optimum solutions. Finally, an example of turbine-type selection was given to illustrate the operation process and prove its validity.

Development of seismic technology and reliability based on vibration tests

International Nuclear Information System (INIS)

Sasaki, Youichi

1997-01-01

This paper deals with some of the vibration tests and investigations on the seismic safety of nuclear power plants (NPPs) in Japan. To ensure the reliability of the seismic safety of nuclear power plants, nuclear power plants in Japan have been designed according to the Technical Guidelines for Aseismic Design of Nuclear Power Plants. This guideline has been developed based on technical date base and findings which were obtained from many vibration tests and investigations. Besides the tests for the guideline, proving tests on seismic reliability of operating nuclear power plants equipment and systems have been carried out. In this paper some vibration tests and their evaluation results are presented. They have crucially contributed to develop the guideline. (J.P.N.)

Development of seismic technology and reliability based on vibration tests

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Youichi [Nuclear Power Engineering Corp., Tokyo (Japan)

1997-03-01

This paper deals with some of the vibration tests and investigations on the seismic safety of nuclear power plants (NPPs) in Japan. To ensure the reliability of the seismic safety of nuclear power plants, nuclear power plants in Japan have been designed according to the Technical Guidelines for Aseismic Design of Nuclear Power Plants. This guideline has been developed based on technical date base and findings which were obtained from many vibration tests and investigations. Besides the tests for the guideline, proving tests on seismic reliability of operating nuclear power plants equipment and systems have been carried out. In this paper some vibration tests and their evaluation results are presented. They have crucially contributed to develop the guideline. (J.P.N.)

A knowledge-based system for fluidization studies

Energy Technology Data Exchange (ETDEWEB)

1990-04-01

Chemical engineers depend on process simulation models to determine optimal'' plant configurations which are technically feasible and economically viable. This research was undertaken to develop a comprehensive knowledge based simulation environment IPSE (Intelligent Process Simulation Environment) that can enhance the productivity of chemical engineers/modelers by serving as an intelligent assistant during all phases of process simulation involving fossil energy processes. In summary, the goals of this research are: application of knowledge-based techniques to the process modeling domain for enhancement of productivity; archiving and distribution of the knowledge of the best experts of process modeling; cross-model inference assistance to modelers not familiar with the process; and development of IPSE to serve as an intelligent tutoring system for process simulation. 18 figs.

Practice of value-based distribution reliability assessment (VBDRA) at Scarborough Public Utilities

International Nuclear Information System (INIS)

Chen, R-L.

1995-01-01

The development of value-based distribution reliability assessment (VBDRA) at Scarborough Public Utilities was described. Load point reliability indices, customer interruption costs (CIC), continuity and service reliability, accuracy of CIC, and the aspects of application of VBDRA were addressed. The application of VBDRA to a long-term rebuild plan for 4.16 kV distribution system was described. The importance of a cost-benefit analysis for implementation of VBDRA was emphasized. In the case of the Scarborough Public Utilities Commission the enhanced feeder reliability assessment was found to influence the allocation of funding to where it provided the most value to customers. 14 refs., 3 tabs., 3 figs

[Job rotation in anaesthesiological care: impacts on knowledge and learning].

Science.gov (United States)

Jordan, Silvia; Brauner, Elisabeth

2008-04-01

Job rotation in anaesthesiological care is explored in this article. Based on discussions of 'high reliability organizations', and based on current theory in social and organizational psychology, we empirically investigated the impact of job rotation on knowledge management and learning. The study was conducted at the University Hospital of Innsbruck during the job training period of novice nurse anaesthetists. Qualitative interviews were conducted as well as a questionnaire administered. Data were collected between September 2003 and June 2005. Observational and interview data were combined with a questionnaire study to assess transactive memory and cooperation using a mixed-method design. Qualitative data were analyzed using GABEK, a computer-supported content analysis system; quantitative data were analyzed statistically with SPSS. Results indicate that job rotation had both positive and negative effects on knowledge and learning. On the one hand, job rotation can foster flexibility and awareness of a person's own fallibility and lack of knowledge. On the other hand, trust, group cohesion, and social meta-knowledge can be hampered by constant rotation. Consequently, stabilization and change need equal consideration when designing work in high reliability organizations.

Methodology for testing and validating knowledge bases

Science.gov (United States)

Krishnamurthy, C.; Padalkar, S.; Sztipanovits, J.; Purves, B. R.

1987-01-01

A test and validation toolset developed for artificial intelligence programs is described. The basic premises of this method are: (1) knowledge bases have a strongly declarative character and represent mostly structural information about different domains, (2) the conditions for integrity, consistency, and correctness can be transformed into structural properties of knowledge bases, and (3) structural information and structural properties can be uniformly represented by graphs and checked by graph algorithms. The interactive test and validation environment have been implemented on a SUN workstation.

Knowledge based system for control rod programming of BWRs

International Nuclear Information System (INIS)

Fukuzaki, Takaharu; Yoshida, Ken-ichi; Kobayashi, Yasuhiro

1988-01-01

A knowledge based system has been developed to support designers in control rod programming of BWRs. The programming searches through optimal control rod patterns to realize safe and effective burning of nuclear fuel. Knowledge of experienced designers plays the main role in minimizing the number of calculations by the core performance evaluation code. This code predicts power distibution and thermal margins of the nuclear fuel. This knowledge is transformed into 'if-then' type rules and subroutines, and is stored in a knowledge base of the knowledge based system. The system consists of working area, an inference engine and the knowledge base. The inference engine can detect those data which have to be regenerated, call those subroutine which control the user's interface and numerical computations, and store competitive sets of data in different parts of the working area. Using this system, control rod programming of a BWR plant was traced with about 500 rules and 150 subroutines. Both the generation of control rod patterns for the first calculation of the code and the modification of a control rod pattern to reflect the calculation were completed more effectively than in a conventional method. (author)

A Knowledge-Base for a Personalized Infectious Disease Risk Prediction System.

Science.gov (United States)

Vinarti, Retno; Hederman, Lucy

2018-01-01

We present a knowledge-base to represent collated infectious disease risk (IDR) knowledge. The knowledge is about personal and contextual risk of contracting an infectious disease obtained from declarative sources (e.g. Atlas of Human Infectious Diseases). Automated prediction requires encoding this knowledge in a form that can produce risk probabilities (e.g. Bayesian Network - BN). The knowledge-base presented in this paper feeds an algorithm that can auto-generate the BN. The knowledge from 234 infectious diseases was compiled. From this compilation, we designed an ontology and five rule types for modelling IDR knowledge in general. The evaluation aims to assess whether the knowledge-base structure, and its application to three disease-country contexts, meets the needs of personalized IDR prediction system. From the evaluation results, the knowledge-base conforms to the system's purpose: personalization of infectious disease risk.

Reliability Assessment and Reliability-Based Inspection and Maintenance of Offshore Wind Turbines

DEFF Research Database (Denmark)

Ramirez, José Rangel

actions are the most relevant and effective means of control of deterioration. The risk-based inspection planning methodology, based on Bayesian decision theory, represents an important tool to identify the suitable strategy to inspect and control the deterioration in structures such as offshore wind...... performance during the life cycle. The deterioration processes, such as fatigue and corrosion, are typically affecting offshore structural systems. This damage decreases the system performance and increases the risk of failure, thus not fulfilling the established safety criteria. Inspection and maintenance...... to their offshore location, no pollution risks and low human risks since they are unmanned. This allows the allocation of lower reliability level compared to e.g. oil & gas installations. With the incursion to water depths between 20 and 50 meters, the use of jacket and tripod structures represents a feasible...

Knowledge-based system for automatic MBR control.

Science.gov (United States)

Comas, J; Meabe, E; Sancho, L; Ferrero, G; Sipma, J; Monclús, H; Rodriguez-Roda, I

2010-01-01

MBR technology is currently challenging traditional wastewater treatment systems and is increasingly selected for WWTP upgrading. MBR systems typically are constructed on a smaller footprint, and provide superior treated water quality. However, the main drawback of MBR technology is that the permeability of membranes declines during filtration due to membrane fouling, which for a large part causes the high aeration requirements of an MBR to counteract this fouling phenomenon. Due to the complex and still unknown mechanisms of membrane fouling it is neither possible to describe clearly its development by means of a deterministic model, nor to control it with a purely mathematical law. Consequently the majority of MBR applications are controlled in an "open-loop" way i.e. with predefined and fixed air scour and filtration/relaxation or backwashing cycles, and scheduled inline or offline chemical cleaning as a preventive measure, without taking into account the real needs of membrane cleaning based on its filtration performance. However, existing theoretical and empirical knowledge about potential cause-effect relations between a number of factors (influent characteristics, biomass characteristics and operational conditions) and MBR operation can be used to build a knowledge-based decision support system (KB-DSS) for the automatic control of MBRs. This KB-DSS contains a knowledge-based control module, which, based on real time comparison of the current permeability trend with "reference trends", aims at optimizing the operation and energy costs and decreasing fouling rates. In practice the automatic control system proposed regulates the set points of the key operational variables controlled in MBR systems (permeate flux, relaxation and backwash times, backwash flows and times, aeration flow rates, chemical cleaning frequency, waste sludge flow rate and recycle flow rates) and identifies its optimal value. This paper describes the concepts and the 3-level architecture

Advances in reliability and system engineering

CERN Document Server

Davim, J

2017-01-01

This book presents original studies describing the latest research and developments in the area of reliability and systems engineering. It helps the reader identifying gaps in the current knowledge and presents fruitful areas for further research in the field. Among others, this book covers reliability measures, reliability assessment of multi-state systems, optimization of multi-state systems, continuous multi-state systems, new computational techniques applied to multi-state systems and probabilistic and non-probabilistic safety assessment.

Reliability-Based Topology Optimization Using Stochastic Response Surface Method with Sparse Grid Design

Directory of Open Access Journals (Sweden)

Qinghai Zhao

2015-01-01

Full Text Available A mathematical framework is developed which integrates the reliability concept into topology optimization to solve reliability-based topology optimization (RBTO problems under uncertainty. Two typical methodologies have been presented and implemented, including the performance measure approach (PMA and the sequential optimization and reliability assessment (SORA. To enhance the computational efficiency of reliability analysis, stochastic response surface method (SRSM is applied to approximate the true limit state function with respect to the normalized random variables, combined with the reasonable design of experiments generated by sparse grid design, which was proven to be an effective and special discretization technique. The uncertainties such as material property and external loads are considered on three numerical examples: a cantilever beam, a loaded knee structure, and a heat conduction problem. Monte-Carlo simulations are also performed to verify the accuracy of the failure probabilities computed by the proposed approach. Based on the results, it is demonstrated that application of SRSM with SGD can produce an efficient reliability analysis in RBTO which enables a more reliable design than that obtained by DTO. It is also found that, under identical accuracy, SORA is superior to PMA in view of computational efficiency.

Knowledge-based processing for aircraft flight control

Science.gov (United States)

Painter, John H.; Glass, Emily; Economides, Gregory; Russell, Paul

1994-01-01

This Contractor Report documents research in Intelligent Control using knowledge-based processing in a manner dual to methods found in the classic stochastic decision, estimation, and control discipline. Such knowledge-based control has also been called Declarative, and Hybid. Software architectures were sought, employing the parallelism inherent in modern object-oriented modeling and programming. The viewpoint adopted was that Intelligent Control employs a class of domain-specific software architectures having features common over a broad variety of implementations, such as management of aircraft flight, power distribution, etc. As much attention was paid to software engineering issues as to artificial intelligence and control issues. This research considered that particular processing methods from the stochastic and knowledge-based worlds are duals, that is, similar in a broad context. They provide architectural design concepts which serve as bridges between the disparate disciplines of decision, estimation, control, and artificial intelligence. This research was applied to the control of a subsonic transport aircraft in the airport terminal area.

Analyzing Reliability and Performance Trade-Offs of HLS-Based Designs in SRAM-Based FPGAs Under Soft Errors

Science.gov (United States)

Tambara, Lucas Antunes; Tonfat, Jorge; Santos, André; Kastensmidt, Fernanda Lima; Medina, Nilberto H.; Added, Nemitala; Aguiar, Vitor A. P.; Aguirre, Fernando; Silveira, Marcilei A. G.

2017-02-01

The increasing system complexity of FPGA-based hardware designs and shortening of time-to-market have motivated the adoption of new designing methodologies focused on addressing the current need for high-performance circuits. High-Level Synthesis (HLS) tools can generate Register Transfer Level (RTL) designs from high-level software programming languages. These tools have evolved significantly in recent years, providing optimized RTL designs, which can serve the needs of safety-critical applications that require both high performance and high reliability levels. However, a reliability evaluation of HLS-based designs under soft errors has not yet been presented. In this work, the trade-offs of different HLS-based designs in terms of reliability, resource utilization, and performance are investigated by analyzing their behavior under soft errors and comparing them to a standard processor-based implementation in an SRAM-based FPGA. Results obtained from fault injection campaigns and radiation experiments show that it is possible to increase the performance of a processor-based system up to 5,000 times by changing its architecture with a small impact in the cross section (increasing up to 8 times), and still increasing the Mean Workload Between Failures (MWBF) of the system.

An Energy-Based Limit State Function for Estimation of Structural Reliability in Shock Environments

Directory of Open Access Journals (Sweden)

Michael A. Guthrie

2013-01-01

Full Text Available 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. 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.

Proposing a Knowledge Base for Teaching Academic Content to English Language Learners: Disciplinary Linguistic Knowledge

Science.gov (United States)

Turkan, Sultan; De Oliveira, Luciana C.; Lee, Okhee; Phelps, Geoffrey

2014-01-01

Background/Context: The current research on teacher knowledge and teacher accountability falls short on information about what teacher knowledge base could guide preparation and accountability of the mainstream teachers for meeting the academic needs of ELLs. Most recently, research on specialized knowledge for teaching has offered ways to…

The biomedical disciplines and the structure of biomedical and clinical knowledge.

Science.gov (United States)

Nederbragt, H

2000-11-01

The relation between biomedical knowledge and clinical knowledge is discussed by comparing their respective structures. The knowledge of a disease as a biological phenomenon is constructed by the interaction of facts and theories from the main biomedical disciplines: epidemiology, diagnostics, clinical trial, therapy development and pathogenesis. Although these facts and theories are based on probabilities and extrapolations, the interaction provides a reliable and coherent structure, comparable to a Kuhnian paradigma. In the structure of clinical knowledge, i.e. knowledge of the patient with the disease, not only biomedical knowledge contributes to the structure but also economic and social relations, ethics and personal experience. However, the interaction between each of the participating "knowledges" in clinical knowledge is not based on mutual dependency and accumulation of different arguments from each, as in biomedical knowledge, but on competition and partial exclusion. Therefore, the structure of biomedical knowledge is different from that of clinical knowledge. This difference is used as the basis for a discussion in which the place of technology, evidence-based medicine and the gap between scientific and clinical knowledge are evaluated.

Knowledge based economy: The role of expert diaspora

Directory of Open Access Journals (Sweden)

Filipović Jovan

2012-01-01

Full Text Available Diasporas stand out as an economic or cultural avant-garde of transformation. This is especially true for academic and other intellectual Diaspora communities, because science and knowledge creation are global enterprises. Proclivity of knowledge workers to move in order to improve and absorb transnational knowledge through Diaspora networks might be an essential quality of an emerging national economy of a developing country. The article treats the role of expert Diaspora in knowledge based economy, innovation and talent management. Besides presenting the essentials of knowledge based economy and innovation, it discusses the role of expert Diaspora in science, technology and innovation (STI capacity building. Also, the article emphasizes the importance of leadership for talent and its implications for Diaspora. Using WEF statistics, it illustrates negative consequences of the sad policy of “Chaseaway the brightest and the best” for innovative capacity, competitiveness, and prosperity of nations.

Integrated approach to knowledge acquisition and safety management of complex plants with emphasis on human factors

International Nuclear Information System (INIS)

Kosmowski, K.T.

1998-01-01

In this paper an integrated approach to the knowledge acquisition and safety management of complex industrial plants is proposed and outlined. The plant is considered within a man-technology-environment (MTE) system. The knowledge acquisition is aimed at the consequent reliability evaluation of human factor and probabilistic modeling of the plant. Properly structured initial knowledge is updated in life-time of the plant. The data and knowledge concerning the topology of safety related systems and their functions are created in a graphical CAD system and are object oriented. Safety oriented monitoring of the plant includes abnormal situations due to external and internal disturbances, failures of hard/software components and failures of human factor. The operation and safety related evidence is accumulated in special data bases. Data/knowledge bases are designed in such a way to support effectively the reliability and safety management of the plant. (author)

Reliability-Based Structural Optimization of Wave Energy Converters

DEFF Research Database (Denmark)

Ambühl, Simon; Kramer, Morten; Sørensen, John Dalsgaard

2014-01-01

More and more wave energy converter (WEC) concepts are reaching prototype level. Once the prototype level is reached, the next step in order to further decrease the levelized cost of energy (LCOE) is optimizing the overall system with a focus on structural and maintenance (inspection) costs......, as well as on the harvested power from the waves. The target of a fully-developed WEC technology is not maximizing its power output, but minimizing the resulting LCOE. This paper presents a methodology to optimize the structural design of WECs based on a reliability-based optimization problem...

Development of knowledge base system linked to material database

International Nuclear Information System (INIS)

Kaji, Yoshiyuki; Tsuji, Hirokazu; Mashiko, Shinichi; Miyakawa, Shunichi; Fujita, Mitsutane; Kinugawa, Junichi; Iwata, Shuichi

2002-01-01

The distributed material database system named 'Data-Free-Way' has been developed by four organizations (the National Institute for Materials Science, the Japan Atomic Energy Research Institute, the Japan Nuclear Cycle Development Institute, and the Japan Science and Technology Corporation) under a cooperative agreement in order to share fresh and stimulating information as well as accumulated information for the development of advanced nuclear materials, for the design of structural components, etc. In order to create additional values of the system, knowledge base system, in which knowledge extracted from the material database is expressed, is planned to be developed for more effective utilization of Data-Free-Way. XML (eXtensible Markup Language) has been adopted as the description method of the retrieved results and the meaning of them. One knowledge note described with XML is stored as one knowledge which composes the knowledge base. Since this knowledge note is described with XML, the user can easily convert the display form of the table and the graph into the data format which the user usually uses. This paper describes the current status of Data-Free-Way, the description method of knowledge extracted from the material database with XML and the distributed material knowledge base system. (author)

Reliability Evaluation of Bridges Based on Nonprobabilistic Response Surface Limit Method

OpenAIRE

Chen, Xuyong; Chen, Qian; Bian, Xiaoya; Fan, Jianping

2017-01-01

Due to many uncertainties in nonprobabilistic reliability assessment of bridges, the limit state function is generally unknown. The traditional nonprobabilistic response surface method is a lengthy and oscillating iteration process and leads to difficultly solving the nonprobabilistic reliability index. This article proposes a nonprobabilistic response surface limit method based on the interval model. The intention of this method is to solve the upper and lower limits of the nonprobabilistic ...

Photovoltaic performance and reliability workshop

Energy Technology Data Exchange (ETDEWEB)

Mrig, L. [ed.

1993-12-01

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

"THE KNOWLEDGE TRIANGLE" IN A KNOWLEDGE-BASED SOCIETY

Directory of Open Access Journals (Sweden)

Rus Mircea-Iosif

2013-07-01

Full Text Available The knowledge-based society is the stage where mankind is found and aims to raise the living standards of population but also to increase the level of knowledge. To achieve this latter goal, the states of the world, and especially those in the European Union, must ensure an adequate funding for its realization, and therefore in 2011 it was decided at EU level the achievement of an Innovation Union, in which are to be involved all the European countries, while to stimulate and finance research and innovation the Horizon 2020 program was proposed. The results of the Program, an ”Innovation Union” have begun to be felt, so in 2011, the major companies headquartered in the European Union increased their investments in R&D by 8.9% compared to 6.1% in 2010. This increase was almost equal to that of the U.S.A. companies (9%, higher than the world average (7.6% and superior to Japanese companies (1.5%. The sectors that used the research-development activity have tended to have increases in employment above average. I believe this information highlights the fact that the European Union may become attractive for research-development and innovation investments even for businesses outside the UE, and this can result in jobs creation and increasing competitivenees of this field of the states of the European Union. In the introductory part of the article, I have briefly presented general notions of the three component activities of the ”knowledge triangle”, in the second part I presented the knowledge society with several features, in the third part, I showed some provisions of the program to stimulate research and innovation Horizon 2020, in the fourth part, I presented an innovation activity connection to private enterprise and entrepreneurial initiative stimulation in the field innovation, and the conclusions shows that research does not stop with achieving the objectives and finding the outcomes research, but is it the background for further

Limits to the reliability of size-based fishing status estimation for data-poor stocks

DEFF Research Database (Denmark)

Kokkalis, Alexandros; Thygesen, Uffe Høgsbro; Nielsen, Anders

2015-01-01

For stocks which are considered “data-poor” no knowledge exist about growth, mortality or recruitment. The only available information is from catches. Here we examine the ability to assess the level of exploitation of a data-poor stock based only on information of the size of individuals in catches....... The model is a formulation of the classic Beverton–Holt theory in terms of size where stock parameters describing growth, natural mortality, recruitment, etc. are determined from life-history invariants. A simulation study was used to compare the reliability of assessments performed under different...... to a considerable improvement in the assessment. Overall, the simulation study demonstrates that it may be possible to classify a data-poor stock as undergoing over- or under-fishing, while the exact status, i.e., how much the fishing mortality is above or below Fmsy, can only be assessed with a substantial...

Review of Reliability-Based Design Optimization Approach and Its Integration with Bayesian Method

Science.gov (United States)

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.

The effect of Web-based Braden Scale training on the reliability of Braden subscale ratings.

Science.gov (United States)

Magnan, Morris A; Maklebust, JoAnn

2009-01-01

The primary purpose of this study was to evaluate the effect of Web-based Braden Scale training on the reliability of Braden Scale subscale ratings made by nurses working in acute care hospitals. A secondary purpose was to describe the distribution of reliable Braden subscale ratings before and after Web-based Braden Scale training. Secondary analysis of data from a recently completed quasi-experimental, pretest-posttest, interrater reliability study. A convenience sample of RNs working at 3 Michigan medical centers voluntarily participated in the study. RN participants included nurses who used the Braden Scale regularly at their place of employment ("regular users") as well as nurses who did not use the Braden Scale at their place of employment ("new users"). Using a pretest-posttest, quasi-experimental design, pretest interrater reliability data were collected to identify the percentage of nurses making reliable Braden subscale assessments. Nurses then completed a Web-based Braden Scale training module after which posttest interrater reliability data were collected. The reliability of nurses' Braden subscale ratings was determined by examining the level of agreement/disagreement between ratings made by an RN and an "expert" rating the same patient. In total, 381 RN-to-expert dyads were available for analysis. During both the pretest and posttest periods, the percentage of reliable subscale ratings was highest for the activity subscale, lowest for the moisture subscale, and second lowest for the nutrition subscale. With Web-based Braden Scale training, the percentage of reliable Braden subscale ratings made by new users increased for all 6 subscales with statistically significant improvements in the percentage of reliable assessments made on 3 subscales: sensory-perception, moisture, and mobility. Training had virtually no effect on the percentage of reliable subscale ratings made by regular users of the Braden Scale. With Web-based Braden Scale training the

Exploring Secondary Students' Knowledge and Misconceptions about Influenza: Development, validation, and implementation of a multiple-choice influenza knowledge scale

Science.gov (United States)

Romine, William L.; Barrow, Lloyd H.; Folk, William R.

2013-07-01

Understanding infectious diseases such as influenza is an important element of health literacy. We present a fully validated knowledge instrument called the Assessment of Knowledge of Influenza (AKI) and use it to evaluate knowledge of influenza, with a focus on misconceptions, in Midwestern United States high-school students. A two-phase validation process was used. In phase 1, an initial factor structure was calculated based on 205 students of grades 9-12 at a rural school. In phase 2, one- and two-dimensional factor structures were analyzed from the perspectives of classical test theory and the Rasch model using structural equation modeling and principal components analysis (PCA) on Rasch residuals, respectively. Rasch knowledge measures were calculated for 410 students from 6 school districts in the Midwest, and misconceptions were verified through the χ 2 test. Eight items measured knowledge of flu transmission, and seven measured knowledge of flu management. While alpha reliability measures for the subscales were acceptable, Rasch person reliability measures and PCA on residuals advocated for a single-factor scale. Four misconceptions were found, which have not been previously documented in high-school students. The AKI is the first validated influenza knowledge assessment, and can be used by schools and health agencies to provide a quantitative measure of impact of interventions aimed at increasing understanding of influenza. This study also adds significantly to the literature on misconceptions about influenza in high-school students, a necessary step toward strategic development of educational interventions for these students.

Knowledge-based reasoning in the Paladin tactical decision generation system

Science.gov (United States)

Chappell, Alan R.

1993-01-01

A real-time tactical decision generation system for air combat engagements, Paladin, has been developed. A pilot's job in air combat includes tasks that are largely symbolic. These symbolic tasks are generally performed through the application of experience and training (i.e. knowledge) gathered over years of flying a fighter aircraft. Two such tasks, situation assessment and throttle control, are identified and broken out in Paladin to be handled by specialized knowledge based systems. Knowledge pertaining to these tasks is encoded into rule-bases to provide the foundation for decisions. Paladin uses a custom built inference engine and a partitioned rule-base structure to give these symbolic results in real-time. This paper provides an overview of knowledge-based reasoning systems as a subset of rule-based systems. The knowledge used by Paladin in generating results as well as the system design for real-time execution is discussed.

LIF: A new Kriging based learning function and its application to structural reliability analysis

International Nuclear Information System (INIS)

Sun, Zhili; Wang, Jian; Li, Rui; Tong, Cao

2017-01-01

The main task of structural reliability analysis is to estimate failure probability of a studied structure taking randomness of input variables into account. To consider structural behavior practically, numerical models become more and more complicated and time-consuming, which increases the difficulty of reliability analysis. Therefore, sequential strategies of design of experiment (DoE) are raised. In this research, a new learning function, named least improvement function (LIF), is proposed to update DoE of Kriging based reliability analysis method. LIF values how much the accuracy of estimated failure probability will be improved if adding a given point into DoE. It takes both statistical information provided by the Kriging model and the joint probability density function of input variables into account, which is the most important difference from the existing learning functions. Maximum point of LIF is approximately determined with Markov Chain Monte Carlo(MCMC) simulation. A new reliability analysis method is developed based on the Kriging model, in which LIF, MCMC and Monte Carlo(MC) simulation are employed. Three examples are analyzed. Results show that LIF and the new method proposed in this research are very efficient when dealing with nonlinear performance function, small probability, complicated limit state and engineering problems with high dimension. - Highlights: • Least improvement function (LIF) is proposed for structural reliability analysis. • LIF takes both Kriging based statistical information and joint PDF into account. • A reliability analysis method is constructed based on Kriging, MCS and LIF.

Knowledge bases for modelisation of industrial plants

International Nuclear Information System (INIS)

Lorre, J.P.; Evrard, J.M.; Dorlet, E.

1992-01-01

Our experience in the development of numerous knowledge based control systems for large industrial applications has led us to the expression of a generic problem and to the implementation of the tools to address it. This paper illustrates, with different practical examples that we have encountered, the principal concepts found in the modelling and management of large industrial knowledge bases. We thus arrive at the definition of the formalism to be used. The principles described are now integrated into the tool SPIRAL and are currently being employed in the development of several applications

Models for reliability and management of NDT data

International Nuclear Information System (INIS)

Simola, K.

1997-01-01

In this paper the reliability of NDT measurements was approached from three directions. We have modelled the flaw sizing performance, the probability of flaw detection, and developed models to update the knowledge of true flaw size based on sequential measurement results and flaw sizing reliability model. In discussed models the measured flaw characteristics (depth, length) are assumed to be simple functions of the true characteristics and random noise corresponding to measurement errors, and the models are based on logarithmic transforms. Models for Bayesian updating of the flaw size distributions were developed. Using these models, it is possible to take into account the prior information of the flaw size and combine it with the measured results. A Bayesian approach could contribute e. g. to the definition of an appropriate combination of practical assessments and technical justifications in NDT system qualifications, as expressed by the European regulatory bodies

Developing and validating a nutrition knowledge questionnaire: key methods and considerations.

Science.gov (United States)

Trakman, Gina Louise; Forsyth, Adrienne; Hoye, Russell; Belski, Regina

2017-10-01

To outline key statistical considerations and detailed methodologies for the development and evaluation of a valid and reliable nutrition knowledge questionnaire. Literature on questionnaire development in a range of fields was reviewed and a set of evidence-based guidelines specific to the creation of a nutrition knowledge questionnaire have been developed. The recommendations describe key qualitative methods and statistical considerations, and include relevant examples from previous papers and existing nutrition knowledge questionnaires. Where details have been omitted for the sake of brevity, the reader has been directed to suitable references. We recommend an eight-step methodology for nutrition knowledge questionnaire development as follows: (i) definition of the construct and development of a test plan; (ii) generation of the item pool; (iii) choice of the scoring system and response format; (iv) assessment of content validity; (v) assessment of face validity; (vi) purification of the scale using item analysis, including item characteristics, difficulty and discrimination; (vii) evaluation of the scale including its factor structure and internal reliability, or Rasch analysis, including assessment of dimensionality and internal reliability; and (viii) gathering of data to re-examine the questionnaire's properties, assess temporal stability and confirm construct validity. Several of these methods have previously been overlooked. The measurement of nutrition knowledge is an important consideration for individuals working in the nutrition field. Improved methods in the development of nutrition knowledge questionnaires, such as the use of factor analysis or Rasch analysis, will enable more confidence in reported measures of nutrition knowledge.

A novel ontology approach to support design for reliability considering environmental effects.

Science.gov (United States)

Sun, Bo; Li, Yu; Ye, Tianyuan; Ren, Yi

2015-01-01

Environmental effects are not considered sufficiently in product design. Reliability problems caused by environmental effects are very prominent. This paper proposes a method to apply ontology approach in product design. During product reliability design and analysis, environmental effects knowledge reusing is achieved. First, the relationship of environmental effects and product reliability is analyzed. Then environmental effects ontology to describe environmental effects domain knowledge is designed. Related concepts of environmental effects are formally defined by using the ontology approach. This model can be applied to arrange environmental effects knowledge in different environments. Finally, rubber seals used in the subhumid acid rain environment are taken as an example to illustrate ontological model application on reliability design and analysis.

The "Digital Friend": A knowledge-based decision support system for space crews

Science.gov (United States)

Hoermann, Hans-Juergen; Johannes, Bernd; Petrovich Salnitski, Vyacheslav

Space travel of far distances presents exceptional strain on the medical and psychological well-being of the astronauts who undertake such missions. An intelligent knowledge management system has been developed, to assist space crews on long-duration missions as an autonomous decision support system, called the "Digital Friend". This system will become available upon request for the purpose of coaching group processes and individual performance levels as well as aiding in tactical decision processes by taking crew condition parameters into account. In its initial stage, the "Digital Friend" utilizes interconnected layers of knowledge, which encompass relevant models of operational, situational, individual psycho-physiological as well as group processes. An example is the human life science model that contains historic, diagnostic, and prognostic knowledge about the habitual, actual, and anticipated patterns of physiological, cognitive, and group psychology parameters of the crew members. Depending on the available data derived from pre-mission screening, regular check-ups, or non-intrusive onboard monitoring, the "Digital Friend" can generate a situational analysis and diagnose potential problems. When coping with the effects of foreseeable and unforeseen stressors encountered during the mission, the system can provide feedback and support the crew with a recommended course of actions. The first prototype of the "Digital Friend" employs the Neurolab/Healthlab platform developed in a cooperation of DLR and IBMP. The prototype contains psycho-physiological sensors with multiple Heally Satellites that relay data to the intelligent Heally Masters and a telemetric Host station. The analysis of data from a long-term simulation study illustrates how the system can be used to estimate the operators' current level of skill reliability based on Salnitski's model [V. Salnitski, A. Bobrov, A. Dudukin, B. Johannes, Reanalysis of operators reliability in professional skills

Knowledge and knowledge bases in the learning process og polish companies

DEFF Research Database (Denmark)

Lorentzen, Anne

2003-01-01

strategies of which are analysed and compared. These strategies have much in common and can be seen as quite successful. Some common problems also exist in relation to mismatches within and between the different knowledge bases. The differences are none the less interesting to consider. They are due......The paper deals with the learning and innovation strategies of manufacturing companies in the economies of transformation. The point of departure is the development of a theoretical framework dealing innovation, knowledge and learning. The case is two manufacturing companies in Poland, the learning...

Reliability-Based Design and Planning of Inspection and Monitoring of Offshore Wind Turbines

DEFF Research Database (Denmark)

Marquez-Dominguez, Sergio

Maintaining and developing a sustainable wind industry is the main motivation of this PhD thesis entitled “Reliability-based design and planning of inspection and monitoring of offshore wind turbines”. In this thesis, statistical methods and probability theory are important mathematical tools used...... and offshore wind turbine foundations with the aim of improving the design, decreasing structural costs and increasing benefits. Recently, wind energy technology has started to adopt risk and reliability based inspection planning (RBI) as a methodology based on Bayesian decision theories together...

Assessing Knowledge Sharing Among Academics: A Validation of the Knowledge Sharing Behavior Scale (KSBS).

Science.gov (United States)

Ramayah, T; Yeap, Jasmine A L; Ignatius, Joshua

2014-04-01

There is a belief that academics tend to hold on tightly to their knowledge and intellectual resources. However, not much effort has been put into the creation of a valid and reliable instrument to measure knowledge sharing behavior among the academics. To apply and validate the Knowledge Sharing Behavior Scale (KSBS) as a measure of knowledge sharing behavior within the academic community. Respondents (N = 447) were academics from arts and science streams in 10 local, public universities in Malaysia. Data were collected using the 28-item KSBS that assessed four dimensions of knowledge sharing behavior namely written contributions, organizational communications, personal interactions, and communities of practice. The exploratory factor analysis showed that the items loaded on the dimension constructs that they were supposed to represent, thus proving construct validity. A within-factor analysis revealed that each set of items representing their intended dimension loaded on only one construct, therefore establishing convergent validity. All four dimensions were not perfectly correlated with each other or organizational citizenship behavior, thereby proving discriminant validity. However, all four dimensions correlated with organizational commitment, thus confirming predictive validity. Furthermore, all four factors correlated with both tacit and explicit sharing, which confirmed their concurrent validity. All measures also possessed sufficient reliability (α > .70). The KSBS is a valid and reliable instrument that can be used to formally assess the types of knowledge artifacts residing among academics and the degree of knowledge sharing in relation to those artifacts. © The Author(s) 2014.

Connectivity-Based Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs

Directory of Open Access Journals (Sweden)

Woo-Yong Choi

2009-01-01

Full Text Available We propose the efficient reliable multicast MAC protocol based on the connectivity information among the recipients. Enhancing the BMMM (Batch Mode Multicast MAC protocol, the reliable multicast MAC protocol significantly reduces the RAK (Request for ACK frame transmissions in a reasonable computational time and enhances the MAC performance. By the analytical performance analysis, the throughputs of the BMMM protocol and our proposed MAC protocol are derived. Numerical examples show that our proposed MAC protocol increases the reliable multicast MAC performance for IEEE 802.11 wireless LANs.

The Coming of Knowledge-Based Business.

Science.gov (United States)

Davis, Stan; Botkin, Jim

1994-01-01

Economic growth will come from knowledge-based businesses whose "smart" products filter and interpret information. Businesses will come to think of themselves as educators and their customers as learners. (SK)

A knowledge-based system for prototypical reasoning

Science.gov (United States)

Lieto, Antonio; Minieri, Andrea; Piana, Alberto; Radicioni, Daniele P.

2015-04-01

In this work we present a knowledge-based system equipped with a hybrid, cognitively inspired architecture for the representation of conceptual information. The proposed system aims at extending the classical representational and reasoning capabilities of the ontology-based frameworks towards the realm of the prototype theory. It is based on a hybrid knowledge base, composed of a classical symbolic component (grounded on a formal ontology) with a typicality based one (grounded on the conceptual spaces framework). The resulting system attempts to reconcile the heterogeneous approach to the concepts in Cognitive Science with the dual process theories of reasoning and rationality. The system has been experimentally assessed in a conceptual categorisation task where common sense linguistic descriptions were given in input, and the corresponding target concepts had to be identified. The results show that the proposed solution substantially extends the representational and reasoning 'conceptual' capabilities of standard ontology-based systems.

Design of Accelerated Reliability Test for CNC Motorized Spindle Based on Vibration Signal

Directory of Open Access Journals (Sweden)

Chen Chao

2016-01-01

Full Text Available Motorized spindle is the key functional component of CNC machining centers which is a mechatronics system with long life and high reliability. The reliability test cycle of motorized spindle is too long and infeasible. This paper proposes a new accelerated test for reliability evaluation of motorized spindle. By field reliability test, authors collect and calculate the load data including rotational speed, cutting force and torque. Load spectrum distribution law is analyzed. And authors design a test platform to apply the load spectrum. A new method to define the fuzzy acceleration factor based on the vibration signal is proposed. Then the whole test plan of accelerated reliability test is done.

Reliability analysis with linguistic data: An evidential network approach

International Nuclear Information System (INIS)

Zhang, Xiaoge; Mahadevan, Sankaran; Deng, Xinyang

2017-01-01

In practical applications of reliability assessment of a system in-service, information about the condition of a system and its components is often available in text form, e.g., inspection reports. Estimation of the system reliability from such text-based records becomes a challenging problem. In this paper, we propose a four-step framework to deal with this problem. In the first step, we construct an evidential network with the consideration of available knowledge and data. Secondly, we train a Naive Bayes text classification algorithm based on the past records. By using the trained Naive Bayes algorithm to classify the new records, we build interval basic probability assignments (BPA) for each new record available in text form. Thirdly, we combine the interval BPAs of multiple new records using an evidence combination approach based on evidence theory. Finally, we propagate the interval BPA through the evidential network constructed earlier to obtain the system reliability. Two numerical examples are used to demonstrate the efficiency of the proposed method. We illustrate the effectiveness of the proposed method by comparing with Monte Carlo Simulation (MCS) results. - Highlights: • We model reliability analysis with linguistic data using evidential network. • Two examples are used to demonstrate the efficiency of the proposed method. • We compare the results with Monte Carlo Simulation (MCS).

Reliability data banks

International Nuclear Information System (INIS)

Cannon, A.G.; Bendell, A.

1991-01-01

Following an introductory chapter on Reliability, what is it, why it is needed, how it is achieved and measured, the principles of reliability data bases and analysis methodologies are the subject of the next two chapters. Achievements due to the development of data banks are mentioned for different industries in the next chapter, FACTS, a comprehensive information system for industrial safety and reliability data collection in process plants are covered next. CREDO, the Central Reliability Data Organization is described in the next chapter and is indexed separately, as is the chapter on DANTE, the fabrication reliability Data analysis system. Reliability data banks at Electricite de France and IAEA's experience in compiling a generic component reliability data base are also separately indexed. The European reliability data system, ERDS, and the development of a large data bank come next. The last three chapters look at 'Reliability data banks, - friend foe or a waste of time'? and future developments. (UK)

The Validity and Reliability Characteristics of the M-BACK Questionnaire to Assess the Barriers, Attitudes, Confidence, and Knowledge of Mental Health Staff Regarding Metabolic Health of Mental Health Service Users

Directory of Open Access Journals (Sweden)

Andrew Watkins

2017-12-01

Full Text Available BackgroundAddressing the burden of poor physical health and the subsequent gap in life expectancy experienced by people with mental illness is a major priority in mental health services. To equip mental health staff with the competence to deliver evidence-based interventions, targeted staff training regarding metabolic health is required. In order to evaluate the effectiveness of staff training regarding metabolic health, we aimed to develop a succinct measure to determine the barriers, attitudes, confidence, and knowledge of health practitioners through the development and test–retest reliability of the Metabolic-Barriers, Attitudes, Confidence, and Knowledge Questionnaire (M-BACK.MethodsThe M-BACK questionnaire was developed to evaluate the impact of specialized training in metabolic health care for mental health nurses. Content of the M-BACK was developed from a literature review and refined by an expert review panel and validated via a piloting process. To determine the test–retest reliability of the M-BACK, 31 nursing students recruited from the University of Notre Dame, Sydney completed the questionnaire on two separate occasions, 7 days apart. Intraclass correlation coefficients (ICCs were calculated for the total score, as well as each of the four domains.ResultsPilot testing was undertaken with a sample of 106 mental health nurses with a mean age 48.2, ranging from 24 to 63 years of age, who participated in six training courses. Questionnaire development resulted in a 16-item instrument, with each item is scored on a five-point Likert scale ranging from “strongly disagree” to “strongly agree.” Test–retest reliability of the M-BACK was completed by 30 of 31 nursing students recruited, ICCs ranged from 0.62 to 0.96.ConclusionThe M-BACK is a reliable measure of the key elements of practitioner perceptions of barriers, and their knowledge, attitudes, and confidence regarding metabolic monitoring in people with mental

IGENPRO knowledge-based digital system for process transient diagnostics and management

International Nuclear Information System (INIS)

Morman, J.A.; Reifman, J.; Vitela, J.E.; Wei, T.Y.C.; Applequist, C.A.; Hippely, P.; Kuk, W.; Tsoukalas, L.H.

1998-01-01

Verification and validation issues have been perceived as important factors in the large scale deployment of knowledge-based digital systems for plant transient diagnostics and management. Research and development (R and D) is being performed on the IGENPRO package to resolve knowledge base issues. The IGENPRO approach is to structure the knowledge bases on generic thermal-hydraulic (T-H) first principles and not use the conventional event-basis structure. This allows for generic comprehensive knowledge, relatively small knowledge bases and above all the possibility of T-H system/plant independence. To demonstrate concept feasibility the knowledge structure has been implemented in the diagnostic module PRODIAG. Promising laboratory testing results have been obtained using data from the full scope Braidwood PWR operator training simulator. This knowledge structure is now being implemented in the transient management module PROMANA to treat unanticipated events and the PROTREN module is being developed to process actual plant data. Achievement of the IGENPRO R and D goals should contribute to the acceptance of knowledge-based digital systems for transient diagnostics and management. (author)

IGENPRO knowledge-based digital system for process transient diagnostics and management

International Nuclear Information System (INIS)

Morman, J.A.; Reifman, J.; Wei, T.Y.C.

1997-01-01

Verification and validation issues have been perceived as important factors in the large scale deployment of knowledge-based digital systems for plant transient diagnostics and management. Research and development (R ampersand D) is being performed on the IGENPRO package to resolve knowledge base issues. The IGENPRO approach is to structure the knowledge bases on generic thermal-hydraulic (T-H) first principles and not use the conventional event-basis structure. This allows for generic comprehensive knowledge, relatively small knowledge bases and above all the possibility of T-H system/plant independence. To demonstrate concept feasibility the knowledge structure has been implemented in the diagnostic module PRODIAG. Promising laboratory testing results have been obtained using data from the full scope Braidwood PWR operator training simulator. This knowledge structure is now being implemented in the transient management module PROMANA to treat unanticipated events and the PROTREN module is being developed to process actual plant data. Achievement of the IGENPRO R ampersand D goals should contribute to the acceptance of knowledge-based digital systems for transient diagnostics and management

Inter-rater reliability of an observation-based ergonomics assessment checklist for office workers.

Science.gov (United States)

Pereira, Michelle Jessica; Straker, Leon Melville; Comans, Tracy Anne; Johnston, Venerina

2016-12-01

To establish the inter-rater reliability of an observation-based ergonomics assessment checklist for computer workers. A 37-item (38-item if a laptop was part of the workstation) comprehensive observational ergonomics assessment checklist comparable to government guidelines and up to date with empirical evidence was developed. Two trained practitioners assessed full-time office workers performing their usual computer-based work and evaluated the suitability of workstations used. Practitioners assessed each participant consecutively. The order of assessors was randomised, and the second assessor was blinded to the findings of the first. Unadjusted kappa coefficients between the raters were obtained for the overall checklist and subsections that were formed from question-items relevant to specific workstation equipment. Twenty-seven office workers were recruited. The inter-rater reliability between two trained practitioners achieved moderate to good reliability for all except one checklist component. This checklist has mostly moderate to good reliability between two trained practitioners. Practitioner Summary: This reliable ergonomics assessment checklist for computer workers was designed using accessible government guidelines and supplemented with up-to-date evidence. Employers in Queensland (Australia) can fulfil legislative requirements by using this reliable checklist to identify and subsequently address potential risk factors for work-related injury to provide a safe working environment.

Constructing and Refining Knowledge Bases: A Collaborative Apprenticeship Multistrategy Learning Approach

National Research Council Canada - National Science Library

Tecuci, Gheorghe

2000-01-01

This research has developed a theory, methodology and learning agent shell for development of knowledge bases and knowledge-based agents, by domain experts, with limited assistance from knowledge engineers...

Development of a Knowledge Base for Enduser Consultation of AAL-Systems.

Science.gov (United States)

Röll, Natalie; Stork, Wilhelm; Rosales, Bruno; Stephan, René; Knaup, Petra

2016-01-01

Manufacturer information, user experiences and product availability of assistive living technologies are usually not known to citizens or consultation centers. The different knowledge levels concerning the availability of technology shows the need for building up a knowledge base. The aim of this contribution is the definition of requirements in the development of knowledge bases for AAL consultations. The major requirements, such as a maintainable and easy to use structure were implemented into a web based knowledge base, which went productive in ~3700 consulting interviews of municipal technology information centers. Within this field phase the implementation of the requirements for a knowledge base in the field of AAL consulting was evaluated and further developed.

Knowledge-based interpretation of cranial MR images

International Nuclear Information System (INIS)

Kuhn, M.H.; Menhardt, W.; Schmidt, K.H.

1987-01-01

A computerized system is described that can be used to evaluate an MR tomogram automatically to support clinical identification of anatomic and pathologic structures and to aid in planning MR measurements. Knowledge from three domains is used for the interpretation of an MR image: nosologic knowledge, knowledge of MR imaging parameters, and anatomic and morphologic knowledge. Nosologic information is used to generate hypotheses about possible pathologies and their locations, based on the signs and symptoms of the patient. With this information, a sequence of interpretation modules, each able to detect substructures in already detected structures with the aid of techniques from image processing, pattern recognition, and artificial intelligence, is generated and executed

Big data analytics in immunology: a knowledge-based approach.

Science.gov (United States)

Zhang, Guang Lan; Sun, Jing; Chitkushev, Lou; Brusic, Vladimir

2014-01-01

With the vast amount of immunological data available, immunology research is entering the big data era. These data vary in granularity, quality, and complexity and are stored in various formats, including publications, technical reports, and databases. The challenge is to make the transition from data to actionable knowledge and wisdom and bridge the knowledge gap and application gap. We report a knowledge-based approach based on a framework called KB-builder that facilitates data mining by enabling fast development and deployment of web-accessible immunological data knowledge warehouses. Immunological knowledge discovery relies heavily on both the availability of accurate, up-to-date, and well-organized data and the proper analytics tools. We propose the use of knowledge-based approaches by developing knowledgebases combining well-annotated data with specialized analytical tools and integrating them into analytical workflow. A set of well-defined workflow types with rich summarization and visualization capacity facilitates the transformation from data to critical information and knowledge. By using KB-builder, we enabled streamlining of normally time-consuming processes of database development. The knowledgebases built using KB-builder will speed up rational vaccine design by providing accurate and well-annotated data coupled with tailored computational analysis tools and workflow.

Big Data Analytics in Immunology: A Knowledge-Based Approach

Directory of Open Access Journals (Sweden)

Guang Lan Zhang

2014-01-01

Full Text Available With the vast amount of immunological data available, immunology research is entering the big data era. These data vary in granularity, quality, and complexity and are stored in various formats, including publications, technical reports, and databases. The challenge is to make the transition from data to actionable knowledge and wisdom and bridge the knowledge gap and application gap. We report a knowledge-based approach based on a framework called KB-builder that facilitates data mining by enabling fast development and deployment of web-accessible immunological data knowledge warehouses. Immunological knowledge discovery relies heavily on both the availability of accurate, up-to-date, and well-organized data and the proper analytics tools. We propose the use of knowledge-based approaches by developing knowledgebases combining well-annotated data with specialized analytical tools and integrating them into analytical workflow. A set of well-defined workflow types with rich summarization and visualization capacity facilitates the transformation from data to critical information and knowledge. By using KB-builder, we enabled streamlining of normally time-consuming processes of database development. The knowledgebases built using KB-builder will speed up rational vaccine design by providing accurate and well-annotated data coupled with tailored computational analysis tools and workflow.

Online Identification with Reliability Criterion and State of Charge Estimation Based on a Fuzzy Adaptive Extended Kalman Filter for Lithium-Ion Batteries

Directory of Open Access Journals (Sweden)

Zhongwei Deng

2016-06-01

Full Text Available In the field of state of charge (SOC estimation, the Kalman filter has been widely used for many years, although its performance strongly depends on the accuracy of the battery model as well as the noise covariance. The Kalman gain determines the confidence coefficient of the battery model by adjusting the weight of open circuit voltage (OCV correction, and has a strong correlation with the measurement noise covariance (R. In this paper, the online identification method is applied to acquire the real model parameters under different operation conditions. A criterion based on the OCV error is proposed to evaluate the reliability of online parameters. Besides, the equivalent circuit model produces an intrinsic model error which is dependent on the load current, and the property that a high battery current or a large current change induces a large model error can be observed. Based on the above prior knowledge, a fuzzy model is established to compensate the model error through updating R. Combining the positive strategy (i.e., online identification and negative strategy (i.e., fuzzy model, a more reliable and robust SOC estimation algorithm is proposed. The experiment results verify the proposed reliability criterion and SOC estimation method under various conditions for LiFePO4 batteries.

User-based and Cognitive Approaches to Knowledge Organization

DEFF Research Database (Denmark)

Hjørland, Birger

2013-01-01

’s PageRank are not based on the empirical studies of users. In knowledge organization, the Book House System is one example of a system based on user studies. In cognitive science the important WordNet database is claimed to be based on psychological research. This article considers such examples......In the 1970s and 1980s, forms of user-based and cognitive approaches to knowledge organization came to the forefront as part of the overall development in library and information science and in the broader society. The specific nature of userbased approaches is their basis in the empirical studies...

The HEP Software and Computing Knowledge Base

Science.gov (United States)

Wenaus, T.

2017-10-01

HEP software today is a rich and diverse domain in itself and exists within the mushrooming world of open source software. As HEP software developers and users we can be more productive and effective if our work and our choices are informed by a good knowledge of what others in our community have created or found useful. The HEP Software and Computing Knowledge Base, hepsoftware.org, was created to facilitate this by serving as a collection point and information exchange on software projects and products, services, training, computing facilities, and relating them to the projects, experiments, organizations and science domains that offer them or use them. It was created as a contribution to the HEP Software Foundation, for which a HEP S&C knowledge base was a much requested early deliverable. This contribution will motivate and describe the system, what it offers, its content and contributions both existing and needed, and its implementation (node.js based web service and javascript client app) which has emphasized ease of use for both users and contributors.

Development of reliability-based load and resistance factor design methods for piping

International Nuclear Information System (INIS)

Ayyub, Bilal M.; Hill, Ralph S. III; Balkey, Kenneth R.

2003-01-01

Current American Society of Mechanical Engineers (ASME) nuclear codes and standards rely primarily on deterministic and mechanistic approaches to design. The American Institute of Steel Construction and the American Concrete Institute, among other organizations, have incorporated probabilistic methodologies into their design codes. ASME nuclear codes and standards could benefit from developing a probabilistic, reliability-based, design methodology. This paper provides a plan to develop the technical basis for reliability-based, load and resistance factor design of ASME Section III, Class 2/3 piping for primary loading, i.e., pressure, deadweight and seismic. The plan provides a proof of concept in that LRFD can be used in the design of piping, and could achieve consistent reliability levels. Also, the results from future projects in this area could form the basis for code cases, and additional research for piping secondary loads. (author)

Knowledge-based Fragment Binding Prediction

Science.gov (United States)

Tang, Grace W.; Altman, Russ B.

2014-01-01

Target-based drug discovery must assess many drug-like compounds for potential activity. Focusing on low-molecular-weight compounds (fragments) can dramatically reduce the chemical search space. However, approaches for determining protein-fragment interactions have limitations. Experimental assays are time-consuming, expensive, and not always applicable. At the same time, computational approaches using physics-based methods have limited accuracy. With increasing high-resolution structural data for protein-ligand complexes, there is now an opportunity for data-driven approaches to fragment binding prediction. We present FragFEATURE, a machine learning approach to predict small molecule fragments preferred by a target protein structure. We first create a knowledge base of protein structural environments annotated with the small molecule substructures they bind. These substructures have low-molecular weight and serve as a proxy for fragments. FragFEATURE then compares the structural environments within a target protein to those in the knowledge base to retrieve statistically preferred fragments. It merges information across diverse ligands with shared substructures to generate predictions. Our results demonstrate FragFEATURE's ability to rediscover fragments corresponding to the ligand bound with 74% precision and 82% recall on average. For many protein targets, it identifies high scoring fragments that are substructures of known inhibitors. FragFEATURE thus predicts fragments that can serve as inputs to fragment-based drug design or serve as refinement criteria for creating target-specific compound libraries for experimental or computational screening. PMID:24762971