Grid Quality Measures for PEBI Grids

2021 ◽  
Author(s):  
Ilya Mishev ◽  
Ruslan Rin
Keyword(s):  
Flow Behavior ◽  
Quality Measures ◽  
Approximation Properties ◽  
Approximation Quality ◽  
Flux Approximation ◽  
The Matrix ◽  
Eventual Loss ◽  
Dynamic Measures ◽  
The Impact

Abstract Combining the Perpendicular Bisector (PEBI) grids with the Two Point Flux Approximation (TPFA) scheme demonstrates a potential to accurately model on unstructured grids, conforming to the geological and engineering features of real grids. However, with the increased complexity and resolution of the grids, the PEBI conditions will inevitably be violated in some cells and the approximation properties will be compromised. The objective is to develop accurate and practical grid quality measures that quantify such errors. We critically evaluated the existing grid quality measures and found them lacking predictive power in several areas. The available k-orthogonality measures predict error for flow along the strata, although TPFA provides an accurate approximation. The false-positive results are not only misleading but can overwhelm further analysis. We developed the so-called "truncation error" grid measure which is probably the most accurate measure for flow through a plane face and accurately measures the error along the strata. We also quantified the error due to the face curvature. Curved faces are bound to exist in any real grid. The impact of the quality of the 2-D Delaunay triangulation on TPFA approximation properties is usually not taken into account. We investigate the impact of the size of the smallest angles that can cause considerable increase of the condition number of the matrix and an eventual loss of accuracy, demonstrated with simple examples. Based on the analysis, we provide recommendations. We also show how the size of the largest angles impacts the approximation quality of TPFA. Furthermore, we discuss the impact of the change of the permeability on the TPFA approximation. Finally, we present simple tools that reservoir engineers can use to incorporate the above-mentioned grid quality measures into a workflow. The grid quality measures discussed up to now are static. We also sketch the further extension to dynamic measures, that is, how the static measures can be used to detect change in the flow behavior, potentially leading to increased error. We investigate a comprehensive set of methods, several of them new, to measure the static grid quality of TPFA on PEBI grids and possible extension to dynamic measures. All measures can be easily implemented in production reservoir simulators and examined using the suggested tools in a workflow.

Outcomes

2013 ◽  
pp. 221-226
Author(s):  
David L. Scott
Keyword(s):  
Quality Of Life ◽  
Disease Activity ◽  
Short Form ◽  
Organ Damage ◽  
Confounding Factors ◽  
Short Term ◽  
Self Assessment ◽  
The Matrix ◽  
The Impact

Outcomes evaluate the impact of disease. In rheumatology they span measures of disease activity, end-organ damage, and quality of life. Some outcomes are categorical, such as the presence or absence of remission. Other outcomes involve extended numeric scales such as joint counts, radiographic scores, and quality of life measures. Outcomes can be measured in the short term—weeks and months—or over years and decades. Short-term outcomes, though readily related to treatment, may have less relevance for patients. Clinical trials focus on short-term outcomes whereas observational studies explore longer-term outcomes. The matrix of rheumatic disease outcomes is exemplified by rheumatoid arthritis. Its outcomes span disease activity assessments like joint counts, damage assessed by erosive scores, quality of life evaluated by disease-specific measures like the Health Assessment Questionnaire (HAQ) or generic measures like the Short Form 36 (SF-36), overall assessments like remission, and end result such as joint replacement or death. Outcome measures capture the impact of treating rheumatic diseases. They are influenced by disease severity and effective treatment. They also reflect many confounding factors. These include demographic factors like age, gender, and ethnicity and also deprivation, as poverty worsens outcomes. Comorbidities affect outcomes and patients with multiple comorbid conditions have worse quality of life with poorer outcomes. Patient self-assessment has grown in importance; it is simple and understandable. However, self-assessment can vary over time and does not always reflect assessors’ perspectives. Caution is needed comparing outcomes across units; the various confounding factors and measurement complexities make such comparative analyses challenging.

Medical Staffing Organization and Quality of Care Outcomes in Post-acute Care Settings

2020 ◽  
Author(s):  
Laura M Wagner ◽  
Paul Katz ◽  
Jurgis Karuza ◽  
Connie Kwong ◽  
Lori Sharp ◽  
...  
Keyword(s):  
Nursing Home ◽  
Quality Of Care ◽  
Nursing Homes ◽  
Acute Care ◽  
Quality Measures ◽  
Medical Providers ◽  
Medical Provider ◽  
Provider Characteristics ◽  
The Impact

Abstract Background and Objectives Medical providers are significant drivers of care in post-acute long-term care (PALTC) settings, yet little research has examined the medical provider workforce and its role in ensuring quality of care. Research Design and Methods This study examined the impact of nursing home medical staffing organization (NHMSO) dimensions on the quality of care in U.S. nursing homes. The principal data source was a survey specifically designed to study medical staff organization for post-acute care. Respondents were medical directors and attending physicians providing PALTC. We linked a number of medical provider and nursing home characteristics to the Centers for Medicaid and Medicare Services Nursing Home Compare quality measures hypothesized to be sensitive to input by medical providers. Results From the sample of nursing home medical providers surveyed (n = 1,511), 560 responses were received, yielding a 37% response rate; 425 medical provider responses contained sufficient data for analysis. The results of the impact of NHMSO dimensions were mixed, with many domains not having any significance or having negative relationships between provider characteristics and quality measures. Respondents who reported having a formal process for granting privileges and nursing homes with direct employment of physicians reported significantly fewer emergency visits. Discussion and Implications Further research is needed regarding what quality measures are sensitive to both medical provider characteristics and NHMSO characteristics.

Outcomes

2016 ◽  
Author(s):  
David L. Scott
Keyword(s):  
Quality Of Life ◽  
Disease Activity ◽  
Short Form ◽  
Health Assessment ◽  
Organ Damage ◽  
Confounding Factors ◽  
Short Term ◽  
The Matrix ◽  
The Impact

Outcomes evaluate the impact of disease. In rheumatology they span measures of disease activity, end-organ damage, and quality of life. Some outcomes are categorical, such as the presence or absence of remission. Other outcomes involve extended numeric scales such as joint counts, radiographic scores, and quality of life measures. Outcomes can be measured in the short term—weeks and months—or over years and decades. Short-term outcomes, though readily related to treatment, may have less relevance for patients. Clinical trials focus on short-term outcomes whereas observational studies explore longer-term outcomes. The matrix of rheumatic disease outcomes is exemplified by rheumatoid arthritis. Its outcomes span disease activity assessments like joint counts, damage assessed by erosive scores, quality of life evaluated by disease-specific measures like the Health Assessment Questionnaire (HAQ) or generic measures like the Short Form 36 (SF-36), overall assessments like remission, and end result such as joint replacement or death. Outcome measures are used to capture the impact of treating rheumatic diseases, and are influenced by both disease severity and the effectiveness of treatment. However, they are also influenced by a range of confounding factors. Demographic factors like age, gender, and ethnicity can all have crucial impacts. Deprivation is important, as poverty invariably worsens outcomes. Finally, comorbidities affect outcomes and patients with multiple comorbid conditions usually have worse quality of life with poorer outcomes for all diseases. These multiple confounding factors mean comparing outcomes across units without adjustment will invariably show major differences.

Investigating Prediction Accuracy of Full Reference Objective Video Quality Measures through the ITS4S Dataset

2020 ◽  
Vol 2020 (11) ◽  
pp. 93-1-93-7
Author(s):  
Lohic Fotio Tiotsop ◽  
Antonio Servetti ◽  
Enrico Masala
Keyword(s):  
Video Quality ◽  
Quality Measures ◽  
Point Of View ◽  
Video Sequences ◽  
Spatial Activity ◽  
Full Reference ◽  
Public Dataset ◽  
Video Quality Metrics ◽  
The Impact

Large subjectively annotated datasets are crucial to the development and testing of objective video quality measures (VQMs). In this work we focus on the recently released ITS4S dataset. Relying on statistical tools, we show that the content of the dataset is rather heterogeneous from the point of view of quality assessment. Such diversity naturally makes the dataset a worthy asset to validate the accuracy of video quality metrics (VQMs). In particular we study the ability of VQMs to model the reduction or the increase of the visibility of distortion due to the spatial activity in the content. The study reveals that VQMs are likely to overestimate the perceived quality of processed video sequences whose source is characterized by few spatial details. We then propose an approach aiming at modeling the impact of spatial activity on distortion visibility when objectively assessing the visual quality of a content. The effectiveness of the proposal is validated on the ITS4S dataset as well as on the Netflix public dataset.

The Impact of the Mode of Data Representation for the Result Quality of the Detection and Filtering of Spam

2017 ◽  
pp. 150-168
Author(s):  
Reda Mohamed Hamou ◽  
Abdelmalek Amine ◽  
Moulay Tahar
Keyword(s):  
Unsupervised Learning ◽  
Probabilistic Model ◽  
Hybrid Algorithm ◽  
Data Representation ◽  
The Internet ◽  
The Matrix ◽  
N Gram ◽  
Sensitive Parameters ◽  
The Impact

Spam is now of phenomenal proportions since it represents a high percentage of total emails exchanged on the Internet. In the fight against spam, we are using this article to develop a hybrid algorithm based primarily on the probabilistic model in this case, Naïve Bayes, for weighting the terms of the matrix term -category and second place used an algorithm of unsupervised learning (K-means) to filter two classes, namely spam and ham (legitimate email). To determine the sensitive parameters that make up the classifications we are interested in studying the content of the messages by using a representation of messages using the n-gram words and characters independent of languages (because a message may be received in any language) to later decide what representation to use to get a good classification. We have chosen several metrics as evaluation to validate our results.

scholarly journals Characterisation of Used PP-Based Car Bumpers and Their Recycling Properties

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
M. P. Luda ◽  
V. Brunella ◽  
D. Guaratto
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Impact Resistance ◽  
Dynamic Mechanical Properties ◽  
Speed Test ◽  
The Matrix ◽  
Internal Mixer ◽  
Mineral Fillers ◽  
The Impact

Three used PP-based car bumpers are characterized by many techniques (fractionation, IR, TGA, DSC, DMTA, and SEM). They show different impact and static and dynamic mechanical properties depending on their composition and morphology. It appears that block copolymer compatibilizers constituted by polyethylene-polypropylene sequences allow a better compatibility between the rubber domains and the PP matrix leading to relatively high impact resistance. Indeed if the ethylene sequences of the copolymer are large enough to crystallize, the decreased mobility of the whole system impairs the impact resistance. In addition, a higher amount of rubber in domains regular in shape and of greater dimension (1–3 μm) promotes a more homogeneous dispersion of external force inside the material, decreasing the risk of fracture. The amount of mineral fillers regulates the elastic modulus (the higher the load, the higher the modulus); however, a fairly good interfacial adhesion is required for satisfactory impact strength. All PP-based bumpers have been mechanically recycled in an internal mixer to redistribute oxidized species and to reestablish phase compatibilization. Recycling improves mechanical properties in slow speed test but fails to increase impact strength particularly in filled bumper, in which the quality of the matrix/filler interphase is hard to improve by simple remixing.

scholarly journals Person-centred Quality, Provider Involvement and Family Planning Continuation in India

2020 ◽  
Author(s):  
Nadia Diamond-Smith ◽  
Beth Phillips ◽  
Patience Afulani ◽  
Aradhana Srivast ◽  
Ginger Golub ◽  
...  
Keyword(s):  
Quality Of Care ◽  
Family Planning ◽  
Quality Measures ◽  
Power Dynamics ◽  
Care Experience ◽  
Person Centered Care ◽  
Centered Care ◽  
And Gender ◽  
The Impact

Abstract Background: Quality of care of family planning provision has many dimensions, and measuring and understanding these different components is challenging. Furthermore, understanding which components are most important for women’s experiences and method continuation is essential for improving the quality of care provision. Methods: We use longitudinal data from India to explore the impact of different measures of quality (provider preference, provider involvement, and a newly developed scale of person-centered care experiences) on method continuation. We also look at associations between the quality measures and discuss why different measures may be more salient in different contexts. Results: We find that a woman’s person-centered care experience is not associated with continuation in India. Providers having a strong preference is associated with continuation. Conclusions: Certain measures of person-centered quality appear to impact family planning continuation, but the validated person-centered care measure is not. Socio-cultural factors such as power dynamics and gender norms likely impact expectations, and need to be considered in interpreting and choosing quality measures.

The Impact of the Mode of Data Representation for the Result Quality of the Detection and Filtering of Spam

2013 ◽  
Vol 3 (1) ◽  
pp. 43-59
Author(s):  
Reda Mohamed Hamou ◽  
Abdelmalek Amine
Keyword(s):  
Probabilistic Model ◽  
Hybrid Algorithm ◽  
Data Representation ◽  
The Internet ◽  
Good Classification ◽  
The Matrix ◽  
N Gram ◽  
Sensitive Parameters ◽  
The Impact

Spam is now seized of the Internet in phenomenal proportions since it high represents a percentage of total emails exchanged on the Internet. In the fight against spam, the authors are interested in this article to develop a hybrid algorithm based primarily on the probabilistic model in this case Naïve Bayes for weighting the terms of the matrix term -category and second place used an algorithm of unsupervised learning (K-means) to filter two classes namely spam and ham. To determine the sensitive parameters that improve the classifications the authors are interested in studying the content of the messages by using a representation of messages by the n-gram words and characters independent of languages (because a message may be received in any language) to later decide what representation opt to get a good classification. The authors have chosen several metrics evaluation to validate their results.

scholarly journals Quality of care at safety-net hospitals and the impact on pay-for-performance reimbursement

2019 ◽  
Author(s):  
Reith R. Sarkar ◽  
Patrick T. Courtney ◽  
Katie Bachand ◽  
Paige Sheridan ◽  
Paul Riviere ◽  
...  
Keyword(s):  
Quality Of Care ◽  
Cancer Patients ◽  
Low Income ◽  
Pay For Performance ◽  
Young Male ◽  
Quality Measures ◽  
Safety Net ◽  
High Burden ◽  
The Impact

AbstractBackgroundPay-for-performance reimbursement ties hospital payments to standardized quality of care metrics. The impact of pay-for-performance reimbursement models on safety-net hospitals, which care primarily for uninsured or underinsured patients, remains poorly defined. This study evaluates how standardized quality of care metrics vary by a hospital’s safety-net status, and helps us better understand the potential impact that pay-for-performance reimbursement could have on funding of safety-net hospitals.MethodsWe identified 1,703,865 bladder, breast, cervix, colon, endometrium, gastric, lung, ovary, or rectum cancer patients treated at 1,344 hospitals diagnosed between 2004 and 2015. Safety-net burden was defined for each hospital as the percentage of uninsured or Medicaid patients cared for by that hospital. Hospitals were grouped into low-, medium-, and high-burden hospitals. We evaluated the impact of safety-net burden on concordance with 20 standardized quality of care measures, adjusting for differences in patient age, gender, stage at diagnosis, and comorbidity.ResultsPatients seen at high-burden hospitals were more likely to be young, male, black, Hispanic, and to reside in a low-income and low-educated region. High-burden hospitals had lower adherence to 13 of 20 quality measures compared to low-burden hospitals (all p<0.05). Among the 350 high-burden hospitals, the quality measures were lowest for those caring for the highest fraction of uninsured or Medicaid patients, minority serving hospitals, and those caring for less educated patients (all p<0.001).DiscussionCancer care at safety-net hospitals was associated with lower concordance to standardized quality of care measures. Under a pay-for-performance reimbursement model these lower quality of care scores could decrease payments to safety-net hospitals, potentially increasing health disparities for at-risk cancer patients.

Individual auditor characteristics and audit quality: evidence from nonprofits in the US

2020 ◽  
Vol 32 (4) ◽  
pp. 551-575
Author(s):  
Nancy Chun Feng
Keyword(s):  
Nonprofit Organizations ◽  
Internal Control ◽  
Audit Quality ◽  
Quality Measures ◽  
Content Type ◽  
Audit Firm ◽  
Audit Firms ◽  
The Impact ◽  
Auditor Characteristics

PurposeUsing a sample of US nonprofit organizations, where the identity of the auditor in charge of the audit is revealed, I investigate whether individual auditor characteristics (gender, engagement size and tenure) are associated with audit quality.Design/methodology/approachTo investigate how individual audit partner characteristics affect audit quality, I follow Petrovits et al. (2011) and Fitzgerald et al. (2018) who investigate client characteristics and partner tenure as determinants of ICDs in nonprofits. I add three characteristics of the auditor in charge – gender, engagement size and tenure – to their models. In additional analyses, I use subsamples partitioned by client risk and audit firm size, and find that individual auditor characteristics generally play a more significant role in the issuance of ICDs and QAOs for riskier clients than for less risky clients.FindingsMy results show that female auditors are more likely to report internal control deficiencies and issue qualified audit opinions (QAOs) to nonprofits. I also find that auditors with more Single Audit engagements within the same year are less likely to report ICDs. In addition, auditor tenure is negatively associated with the likelihood of issuing an ICD report, suggesting that auditors become complacent as the length of the auditor–client relationship lengthens or, alternatively, that they are better able to assist their clients in correcting ICDs and in maintaining stronger internal control environments as they gain client-specific knowledge over time. Additional analysis suggests tenure and engagement load results are sensitive to the sample specification employed.Research limitations/implicationsOne caveat of this study is that self-selection bias may be present when a client chooses an audit firm, the audit firm selects a client, and the audit firm assigns a partner to the engagement. Future study with more advanced econometric models is needed to mitigate self-selection bias. Another limitation is that my sample consists of nonprofit organizations and may not be generalizable to for-profit firms. Another caveat of this study is that the tenure variable is truncated compared to prior literature (e.g. Fitzgerald et al., 2018). Also given the rarity of audit quality measures in the nonprofit setting, internal control deficiencies and qualified opinions are used as proxies for audit quality because they reflect both the quality of audit work and the quality of organizations' internal control and financial reporting. Future studies with data including additional audit quality measures could shed more light on the topic.Originality/valueThis study contributes to the literature in several ways. First, this study offers a more comprehensive examination on the impact that a broader set of individual auditor characteristics on audit quality in the nonprofit setting, compared to Fitzgerald et al.'s (2018) study. Second, the findings should be of interest to policymakers who recently mandated engagement partner disclosures from US audit firms (PCAOB, 2015b). Finally, another distinctive feature of this study is that I examine the impact of individual auditor characteristics on audit quality in a setting where Big 4 audit firms are not dominant.

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