305,266 research outputs found

    Cambridge Access Validating Agency

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    V-Model Role Engineering

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    The paper focuses on role engineering which is an important topic in the development of access control system, particularly when considering Role Based Access Control – RBAC models. Despite the wide use of RBAC in various applications, the role engineering process is not a standardized approach. The paper aims to define a methodology and a process model for role engineeringInformation security, access control systems, role based access control systems – RBAC, engineering methodologies, security policies, access control models

    Evaluation of MODIS LAI/FPAR product Collection 6. Part 2: Validation and intercomparison

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    The aim of this paper is to assess the latest version of the MODIS LAI/FPAR product (MOD15A2H), namely Collection 6 (C6). We comprehensively evaluate this product through three approaches: validation with field measurements, intercomparison with other LAI/FPAR products and comparison with climate variables. Comparisons between ground measurements and C6, as well as C5 LAI/FPAR indicate: (1) MODIS LAI is closer to true LAI than effective LAI; (2) the C6 product is considerably better than C5 with RMSE decreasing from 0.80 down to 0.66; (3) both C5 and C6 products overestimate FPAR over sparsely-vegetated areas. Intercomparisons with three existing global LAI/FPAR products (GLASS, CYCLOPES and GEOV1) are carried out at site, continental and global scales. MODIS and GLASS (CYCLOPES and GEOV1) agree better with each other. This is expected because the surface reflectances, from which these products were derived, were obtained from the same instrument. Considering all biome types, the RMSE of LAI (FPAR) derived from any two products ranges between 0.36 (0.05) and 0.56 (0.09). Temporal comparisons over seven sites for the 2001–2004 period indicate that all products properly capture the seasonality in different biomes, except evergreen broadleaf forests, where infrequent observations due to cloud contamination induce unrealistic variations. Thirteen years of C6 LAI, temperature and precipitation time series data are used to assess the degree of correspondence between their variations. The statistically-significant associations between C6 LAI and climate variables indicate that C6 LAI has the potential to provide reliable biophysical information about the land surface when diagnosing climate-driven vegetation responses.Help from MODIS and VIIRS Science team members is gratefully acknowledged. This work is supported by the MODIS program of NASA and partially funded by the National Basic Research Program of China (Grant No. 2013CB733402) and the key program of NSFC (Grant No. 41331171). Kai Yan gives thanks for the scholarship from the China Scholarship Council. (MODIS program of NASA; 2013CB733402 - National Basic Research Program of China; 41331171 - NSFC; China Scholarship Council

    Derivation of diagnostic models based on formalized process knowledge

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    © IFAC.Industrial systems are vulnerable to faults. Early and accurate detection and diagnosis in production systems can minimize down-time, increase the safety of the plant operation, and reduce manufacturing costs. Knowledge- and model-based approaches to automated fault detection and diagnosis have been demonstrated to be suitable for fault cause analysis within a broad range of industrial processes and research case studies. However, the implementation of these methods demands a complex and error-prone development phase, especially due to the extensive efforts required during the derivation of models and their respective validation. In an effort to reduce such modeling complexity, this paper presents a structured causal modeling approach to supporting the derivation of diagnostic models based on formalized process knowledge. The method described herein exploits the Formalized Process Description Guideline VDI/VDE 3682 to establish causal relations among key-process variables, develops an extension of the Signed Digraph model combined with the use of fuzzy set theory to allow more accurate causality descriptions, and proposes a representation of the resulting diagnostic model in CAEX/AutomationML targeting dynamic data access, portability, and seamless information exchange

    Psychometric properties of the Polish version of the eight-item Morisky Medication Adherence Scale in hypertensive adults.

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    Low adherence to pharmacological treatment is often associated with poor blood pressure control, but identification of nonadherent patients in outpatient settings is difficult. The aim of the study was to translate and evaluate the psychometric properties of the Polish version of the structured self-report eight-item Morisky Medication Adherence Scale (MMAS-8) among patients with hypertension. The study was conducted in a family doctor practice between January and July 2015. After a standard "forward-backward" procedure to translate MMAS-8 into Polish, the questionnaire was administered to 160 patients with hypertension. Reliability was tested using a measure of internal consistency (Cronbach's α) and test-retest reliability. Validity was confirmed using known group validity. Three levels of adherence were considered based on the following scores: 0 to <6 (low); 6 to <8 (medium); and 8 (high). Complete questionnaires were returned by 110 respondents (mean age: 60.7 years ±12.6; 54.6% were female). The mean number of pills taken daily was 3.61±4.31. The mean adherence score was 6.42± 2.0. Moderate internal consistency was found (Cronbach's α=0.81), and test-retest reliability was satisfactory (r=0.461-0.905; P<0.001). Reproducibility expressed by Cohen's κ coefficient =0.61 was good. In high-adherent patients, the percentage of well-controlled blood pressure was higher than in low-adherent patients (33.3% vs 19.1%, χ (2)=0.87, P=0.648). Psychometric evaluation of the Polish version of the MMAS-8 indicates that it is a reliable and valid measure tool to detect nonadherent patients. The MMAS-8 may be routinely used to support communication about the medication-taking behavior in hypertensive patients

    Outcomes from collaborative provision audit: student support and information

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    The systematic guideline review: method, rationale, and test on chronic heart failure

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    Background: Evidence-based guidelines have the potential to improve healthcare. However, their de-novo-development requires substantial resources-especially for complex conditions, and adaptation may be biased by contextually influenced recommendations in source guidelines. In this paper we describe a new approach to guideline development-the systematic guideline review method (SGR), and its application in the development of an evidence-based guideline for family physicians on chronic heart failure (CHF). Methods: A systematic search for guidelines was carried out. Evidence-based guidelines on CHF management in adults in ambulatory care published in English or German between the years 2000 and 2004 were included. Guidelines on acute or right heart failure were excluded. Eligibility was assessed by two reviewers, methodological quality of selected guidelines was appraised using the AGREE instrument, and a framework of relevant clinical questions for diagnostics and treatment was derived. Data were extracted into evidence tables, systematically compared by means of a consistency analysis and synthesized in a preliminary draft. Most relevant primary sources were re-assessed to verify the cited evidence. Evidence and recommendations were summarized in a draft guideline. Results: Of 16 included guidelines five were of good quality. A total of 35 recommendations were systematically compared: 25/35 were consistent, 9/35 inconsistent, and 1/35 un-rateable (derived from a single guideline). Of the 25 consistencies, 14 were based on consensus, seven on evidence and four differed in grading. Major inconsistencies were found in 3/9 of the inconsistent recommendations. We re-evaluated the evidence for 17 recommendations (evidence-based, differing evidence levels and minor inconsistencies) - the majority was congruent. Incongruity was found where the stated evidence could not be verified in the cited primary sources, or where the evaluation in the source guidelines focused on treatment benefits and underestimated the risks. The draft guideline was completed in 8.5 man-months. The main limitation to this study was the lack of a second reviewer. Conclusion: The systematic guideline review including framework development, consistency analysis and validation is an effective, valid, and resource saving-approach to the development of evidence-based guidelines

    Haematological malignancy: are we measuring what is important to patients? A systematic review of quality of life instruments

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    © 2018 The Authors. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.The wide range of health‐related quality‐of‐life (HRQoL) instruments used in haematology makes it challenging for haematologists and other care team members in practice to select, use and understand the scoring system and finally interpret the results. The main objectives of this study were to: (a) provide a comprehensive list of quality‐of‐life issues important to patients suffering from haematological malignancies, identified through the literature; (b) provide a list of health‐related quality‐of‐life (HRQoL) instruments used in haematological malignancies in both daily clinical practice and research; and (c) evaluate the relevance and comprehensibility of the identified instruments in haematological malignancies. Systematic literature review of two databases, followed by addition of articles by manual searching, was carried out. The articles focusing on the primary studies, which have used semi‐structured/structured interviews or surveys to identify issues important to HM patients, and other studies describing the results of testing measurement properties, such as reliability, validity and responsiveness of the instruments currently used to evaluate the HRQoL in different HMs, were included. Fifty‐seven studies reported development and validation of 30 HRQoL instruments, which have been used in haematology. Twenty‐four studies were identified using qualitative methods to report HRQoL issues and symptoms from a patient's perspective. No identified instrument captured all the issues identified from the qualitative studies. None of the instruments reviewed appeared to have been developed for use in clinical practice and specifically for patients with HM, except MyPOS. Furthermore, measurement properties were established, largely, in clinical trial scenarios. There is a need for development of a new HRQoL instrument entirely based on involvement of patients with haematological malignancies.Peer reviewe
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