Reliable Criteria Research Articles

A machine learning based prediction model for the impact mechanical response of composite laminates considering microstructure sensitive transverse properties

AbstractThe accurate and efficient prediction of impact mechanical response is crucial for safety design of composite structures. In this work, high‐fidelity representative volume elements (RVEs) with fiber, matrix and fiber/matrix interface are established, in which random fiber distributions are considered. A failure envelope under transverse loads is proposed based on computational micromechanical RVEs, and it is implemented by ABAQUS VUMAT subroutines to predict the mechanical response of composite laminates under impact loads. Based on a dataset from computational macromechanical finite element simulations, an artificial neural network model is established and trained. It is found that the random fiber distribution introduced a more obvious fluctuation to tension/compression strength than shear strength. The proposed failure criteria showed a better performance than Hashin and Tsai‐Wu criteria especially in combined compression and shear loads. An ANN model with 8 hidden layers can achieve the prediction with an acceptable coefficient of determination (R2) 0.98 and loss functions of mean absolute error (MAE) 71. For certain impact loading conditions, the well trained machine learning model predicted impact contact force history within 30 min, while the FEA costs about more than 75 min on the same computer. The prediction speed is increased by over 60% for certain impact loading conditions. It is hence shown that this method provides a potential alternative for evaluation of the impact resistance of composite structures.Highlights High‐fidelity computational micromechanics analysis based on representative volume elements are performed to uncover the complex relationship between microstructure and transverse strengths of composite laminates. The microstructure dependent transverse strength criterion shows high accuracy in combined compression and shear loads compared with Hashin and Tsai‐Wu criteria. A multi‐layer artificial neural network model is established and trained for the rapid prediction of impact force history for composite laminates. The rapid prediction method is achieved with a coefficient of determination of 0.98, and the prediction speed is increased by more than 60% for certain impact loading conditions.

Novel PROMETHEE method with dependent criteria

Novel PROMETHEE method with dependent criteria

Paroxysmal sympathetic hyperactivity in brain damage (scientific review). Part 1

Paroxysmal sympathetic hyperactivity (PSH) is a separate form of fever of central origin and is a neurological syndrome characterized by simultaneous paroxysmal occurrence of hypertension, hyperpyrexia, tachycardia, tachypnea, increased sweating and dystonic posture due to sympathetic activation in brain damage. PSH is a syndrome that can manifest itself in a wide range of clinical symptoms. Paroxysmal sympathetic hyperacti-vity is an example of a clinical correlate of central and autonomic nervous system dysfunction. Almost all cases of PSH are associated with craniocerebral trauma, hypoxia, and acute cerebrovascular accident. There is a disengagement theory and a model of the excitation-inhibition relationship of the PSH pathogenesis. In 2014, an expert consensus group proposed a PSH-assessment measure (PSH-AM), which can not only serve as a reliable diagnostic criterion but also stratify the severity of PSH. Assuming clinical evaluation as the current gold standard, PSH-AM has a sensiti-vity of 94 % when used retrospectively. In the treatment of patients with traumatic brain injury, PSH-AM can help avoid misdiagnosis, increase diagnostic efficiency, save time, and reduce economic costs. Hypodiagnosis of PSH can lead to an increase in mortality, disability, length of hospital stay and material costs, but timely diagnosis will allow optimizing treatment for PSH.

Ranking of Criteria Affecting the Implementation Readiness of Internet of Things in industries Using TISM and Fuzzy TOPSIS Analysis

The Internet of Things (IoT) technology has emerged as a vital driver across various fields, engaging businesses, platforms, and industries. IoT involves a holistic ecosystem and a value chain that necessitates the evaluation of impactful dimensions for successful implementation. This research employs the TISM method to identify driver and dependent criteria regarding IoT implementation readiness and uses the fuzzy TOPSIS method to rank these criteria. In the initial step, 15 criteria were identified through a review of previous studies. The TISM results reveal five levels reflecting the driver power and dependence of the criteria. Based on these results, “Implementation Knowledge and Expertise (C2)”, “Technical and Infrastructural Readiness (C9)” and “Financial and Investment Readiness (C12)” were placed at level 5, marking them as the most driver criteria. Additionally, “Implementation Roadmap (C8)” was identified as the most dependent criterion at level one. According to the fuzzy TOPSIS results, “Senior Management Support (C6)”, “IoT Usage Culture (C1)”, “Business Model Development Capability (C15)”, “Financial and Investment Readiness (C12)” and “Technical and Infrastructural Readiness (C9)” ranked first to fifth, respectively. The combined results provide valuable insights for decision-makers and stakeholders involved in IoT implementation. By determining driver and dependent levels and ranking the criteria, industries can effectively prepare for the successful implementation of IoT.

Absence of Strikes as a Criterion of Efficiency of Staff Security Costs Management at Industrial Enterprises

The article is devoted to studying the possibility of using the absence of strikes as a reliable criterion for measuring the efficiency of staff security cost management at industrial enterprises. The authors proved that the threat of losing a job due to an industrial downturn and economic instability creates conditions under which the interest of employees in protecting enterprises and their owners is higher than the benefits of initiating a labor dispute with them. Based on the results obtained, it is established that despite a low level of social standards in most Ukrainian enterprises, including wage arrears and a low wage level, the number of strikes in Ukraine is scanty. In 2018-2020, there was not a single strike in Ukraine. In 2021, 11 strikes were recorded in the field of education, with the total number of participants accounting for 700 people. Since 2022, strikes in Ukraine have been banned due to the martial law introduction. The article introduces the concept of “employees’ forced loyalty” and elaborates on the classification of loyalty types. The authors proposed the matrix for determining the situations, in which the absence of strikes is a criterion for the efficiency of staff security costs at Ukrainian industrial enterprises. It is grounded that the relationship between employees and employers in Ukraine can be described by the term “neo-feudalism”. The authors systematized the negative consequences of neo-feudalism for labor productivity and staff security. Having considered the results of the study, the authors proposed a list of measures aimed at minimizing and eliminating those consequences.

Face Detection Using Machine Learning

Face Detection plays an essential part in numerous operation exertion including facial identification, security systems, and commerce between people and computers. The prospect of face detection using machine learning shall be explored with main methodologies, which include the use of Haar cascades, CNNs, and SVMs. When comparing the methods, the study focuses on their performance within these criteria of accuracy, computational complexity, and reliability. The experimental findings show that CNNs have better accuracy, achieving high stability of results regardless of the conditions for classification. Also, the study discusses the applicability of these techniques to practical problems, the complexity and time required to execute methods, how the approaches can be scaled up and down depending on the problem’s characteristics. The results indicate that although different approaches like Haar falls are effective for the problem, they fail in more complicated and ever- changing surroundings. That is why, despite the fact that CNNs require greater computational resources, modern face detection systems are based on them due to their accuracy and versatility.

Translation into Portuguese (Brazil), cultural adaptation and validation of Parathyroid Assessment of Symptoms (PAS) in patients with chronic kidney disease and hyperparathyroidism.

Chronic kidney disease (CKD) is related to high morbidity and mortality and loss of quality of life. Likewise, hyperparathyroidism is associated to progressive loss of renal function, with increased phosphate and decrease calcium levels, which induce the secretion of parathyroid hormone. To translate into Portuguese (Brazil), culturally adapt and validate the questionnaire Parathyroid Symptoms Assessment (PAS), following reliability and validity criteria in patients with chronic kidney disease and hyperparathyroidism. Methodological and cross-sectional study, carried out at São Lucas Hospital/PUCRS, Porto Alegre, Brazil. The PAS questionnaire validation process followed protocols from previous studies. After translating into Portuguese, it was applied to 100 patients with secondary (SHPT) and tertiary or persistent (THPT) hyperparathyroidism. For PAS validation data, patients responded to the Short Form Health 36 (SF-36) questionnaire. Reliability criteria were evaluated using intraclass correlation coefficient (ICC) and Cronbach's alpha (α-C). Validity was assessed by Spearman's correlation coefficient between PAS and SF-36 values. Participant's mean age was 55.6 ± 15.6 years, 61% was male, and 68% was diagnosed with SHPT. Among 100 patients, 53% performed a PAS retest (ICC = 0.83). The internal reliability by α-C was 0.86. Negative correlations were observed between PAS questions and SF-36 physical and mental domains, which ranged from 0.3 to 0.7. The Brazilian version of the PAS questionnaire was found to be valid and reliable. The PAS questionnaire can be used to evaluate quality of life in Brazilian patients with hyperparathyroidism who speak Portuguese.

Prospective evaluation of quantitative response parameter in patients with Gastrointestinal Stroma Tumorundergoing tyrosine kinase inhibitor therapy-Impact on clinical outcome.

The purpose of this study was to determine if dual-energy CT (DECT) vital iodine tumor burden (ViTB), a direct assessment of tumor vascularity, allows reliable response assessment in patients with GIST compared to established CT criteria such as RECIST1.1 and modified Choi (mChoi). From 03/2014 to 12/2019, 138 patients (64 years [32-94 years]) with biopsy proven GIST were entered in this prospective, multi-center trial. All patients were treated with tyrosine kinase inhibitors (TKI) and underwent pre-treatment and follow-up DECT examinations for a minimum of 24 months. Response assessment was performed according to RECIST1.1, mChoi, vascular tumor burden (VTB) and DECT ViTB. A change in therapy management could be because of imaging (RECIST1.1 or mChoi) and/or clinical progression. The DECT ViTB criteria had the highest discrimination ability for progression-free survival (PFS) of all criteria in both first line and second line and thereafter treatment, and was significantly superior to RECIST1.1 and mChoi (p < .034). Both, the mChoi and DECT ViTB criteria demonstrated a significantly early median time-to-progression (both delta 2.5 months; both p < .036). Multivariable analysis revealed 6 variables associated with shorter overall survival: secondary mutation (HR = 4.62), polymetastatic disease (HR = 3.02), metastatic second line and thereafter treatment(HR = 2.33), shorter PFS determined by the DECT ViTB criteria (HR = 1.72), multiple organ metastases (HR = 1.51) and lower age (HR = 1.04). DECT ViTB is a reliable response criteria and provides additional value for assessing TKI treatment in GIST patients. A significant superior response discrimination ability for median PFS was observed, including non-responders at first follow-up and patients developing resistance while on therapy.

Detecting overfitting by examining residuals in autoregressive models

The aim of this study is to see how overfitting can be detected using non-rigorous analysis of residuals. The well-known statistical packages was used to simulate data from stationary autoregressive models with Gaussian white noise with mean 0 and variance one. In order to see the effect of realization size on our findings, the sample size 50 was used as an example of small realization and the sample size 500 was used as an example of large realization. The method of maximum likelihood was used in the fitting of autoregressive models to the simulated data which is available in the statistical package R. Interesting and promising results were obtained. Our study seems to suggest that comparing estimates with their standard errors is the only reliable criterion in spotting or detecting overfitting. To make sure that the defect in the behavior of the residuals is due only to the over, we used only the same class of models in the simulation and the fitting.

Validity and Reliability of Mathematics Research Instruments: Systematic Review

The difficulties students face in mathematics are due to various factors that hinder their logical understanding. It is crucial that teachers abandon traditional teaching models and adopt new methodologies to overcome these challenges. However, effective implementation of these methodologies requires valid and reliable assessment tools, which has been little explored in previous studies. The objective of this study is to examine the most recent research on the validity and reliability of research instruments in mathematics, it is a systematic review, it has used the PRISMA methodology and 15 scientific articles have been reviewed as a sample. This review seeks to strengthen research in the area and to verify the validity and reliability criteria of the instruments. The results are discussed in relation to the comparison of the instruments and their effectiveness in the field of mathematics, in order to provide useful insights for future research and to improve educational practices in this field.

Simulation of peak properties in thermoluminescence dosimeters with the potential stimulation of all electron traps

In thermoluminescence (TL) models, the competition between energy levels for electron trapping is a direct consequence of conduction band mediation in electron transport. From a theoretical perspective, these competitive effects are considered responsible for many TL phenomena. Furthermore, while they are easily detectable in simulation studies, there are no clear and reliable criteria for their experimental verification. In the present work, it is suggested that in certain materials with narrow band gap energies, existing electron traps can be accessed by thermal stimulation up to 500 °C. It is possible to predict properties through simulation that can then be verified experimentally. The simulation is applied to a complex TL glow curve consisting of four electron trapping levels and one luminescence center. With the appropriate selection of simulation parameter values, the competition is limited solely to electron transport, rather than to significant differences in parameter values. The simulation indicated that the last peak serves as the primary competitor. Furthermore, the shape of the TL glow curve depends on the strength of the competition. When the competitor is strong, the lower temperature peaks behave as first-order peaks, and the shape of the glow curve remains stable as a function of dose. The last peak, which acts as the final competitor, exhibits behavior similar to that of the peak derived from the one trap, one recombination (OTOR) model. This OTOR-like behavior provides an excellent experimental test for the simulation results and, consequently, for the model used. The validity of the simulation was assessed by comparing the input values of kinetic parameters with the output values obtained from computerized glow curve deconvolution (CGCD) analysis for each TL glow curve.

Neurobehavioral features in medication-overuse headache

BackgroundMedication-overuse headache (MOH) has been related to the spectrum of dependence behavior and impaired orbitofrontal cortex function. Alexithymia is a trait comprising deficits in identifying self-emotions and perception. It was the aim of the study to investigate impulsivity and alexithymia, in patients with MOH and perform correlations with cerebral grey matter. Material and methodsPatients with chronic migraine and MOH according to ICHD criteria from a tertiary headache clinic and healthy controls were investigated by a single psychiatrist, using clinical scales for self-control (BIS-11) and alexithymia (TAS-20) and screened for dependence based on DSM-IV criteria. Correlations of BIS-11 and TAS-20 with cerebral grey matter were analysed with the SPM based toolbox CAT12, using high resolution T1weighted MRI-Sequences acquired on a 3 T scanner. ResultsMRI data were available from 30 MOH patients (24 women) and 47 healthy controls (26 women). MOH patients had increased impulsivity (62.2 ± 11.1 vs. 55.7 ± 7.2; p = 0.007) and alexithymia (49.8 ± 14.8 vs. 38.0 ± 6.5; p < 0.001). Analyzing only women, the results remained significant. Ninety percent of patients fulfilled DSM-IV criteria for substance dependence. There was a positive correlation between impulsivity and grey matter in the left middle orbital gyrus in healthy controls but not in patients (p < 0.05, corrected). No correlations with alexithymia and cerebral grey matter were found. ConclusionsThe present study suggests a neurobehavioral basis for MOH, consisting of impaired impulse control, and self-perception along with features of substance dependence. Although decreased orbitofrontal cortex volume was confirmed in this MOH cohort, impulsivity and alexithymia were not correlated with this structural abnormality.

A new validated instrument to assess sustainability perception among university students

Promoting sustainability within university institutions entails conducting assessments to lay the groundwork for developing educational methodologies. This article presents the validation of a quantitative 36-item scale questionnaire to measure university students' perceptions towards sustainability. A total of 285 university students from different Spanish Universities participated in completing the questionnaire. The reliability and validity of the instrument were statistically assessed through Cronbach’s alpha and confirmatory factor analysis. The questionnaire is of mixed character, combining 6-point Likert scale questions (ranging from “Strongly disagree” to “Strongly agree”), closed and open-ended questions. It was structured into six dimensions: knowledge, attitude, willingness to act, behavior, self-efficacy, and affective. The first five dimensions were confirmed by a confirmatory factor analysis, demonstrating a good fit level in the model (RMSEA = 0.043, CFI = 0.972, SRMR = 0.076, TLI = 0.970 and X2/df = 1.45), while the affective dimension was analyzed using a qualitative approach. Internal reliability, found using Cronbach’s alpha, varies between 0.737 and 0.909. The results show that the instrument meets the validity and reliability criteria. Consequently, a valuable tool for academic utilization is suggested, offering a diagnostic and monitoring mechanism for evaluating sustainability perceptions, a topic that has recently garnered significant attention.

Is driving an electric two-wheeler (E2W) safe? Analysing safety risk factors of E2W considering the quality and reliability criteria

PurposeThe purpose of this research is to identify and analyse the perceived risk factors affecting the safety of electric two-wheeler (E2W) riders in urban areas. Given the exponential growth of the global E2W market and the notable challenges offered by E2W vehicles as compared to electric cars, the study aims to propose a managerial framework, to increase the penetration of E2W in the emerging market, as a reliable, and sustainable mobility alternative.Design/methodology/approachThe perceived risk factors of riding E2Ws are relatively scanty, especially in the context of emerging economies. A mixed-method research design is adopted to achieve the research objectives. Four expert groups are interviewed to identify crucial safety risk E2W factors. The grey-Delphi technique is used to confirm the applicability of the extracted risk factors in the Indian context. Next, the Grey-Decision-Making Trial and Evaluation Laboratory (DEMATEL) technique is employed to reveal the causal-prominence relationship among the perceived risk factors. The dominance and prominence scores are used to perform Cause and Effect analysis and estimate the triggering risk factors.FindingsThe finding of the study suggests that reckless adventurism, adverse road conditions, individual characteristics and distraction caused by using mobile phones, as the topmost triggering risk factors that impact the safety of E2Ws drivers. Similarly, reliability on battery performance low velocity and heavy traffic conditions are found to be some of the critical safety factors.Practical implicationsE2Ws are anticipated to represent the future of sustainable mobility in emerging nations. While they provide convenient and quick transportation for daily urban commutes, certain risk factors are contributing to increased accident rates. This research analyses these risk factors to offer a comprehensive view of driver and rider safety. Unlike conventional measures, it considers subjective quality and reliability parameters, such as battery performance and reckless adventurism. Identifying the most significant causal risk factors helps policymakers focus on the most prominent issues, thereby enhancing the adoption of E2Ws in emerging markets.Originality/valueWe have proposed an integrated framework that uses grey theory with Delphi and DEMATEL to analyse the safety risk factors of driving E2W vehicles considering the uncertainty. In addition, the amalgamation of Delphi and DEMATEL helps not only to identify the pertinent safety risk factors, but also bifurcate them into cause-and-effect groups considering the mutual relationship between them. The framework will enable practitioners and policymakers to design preventive strategies to minimize risk and boost the penetration of E2Ws in an emerging country, like India.

Clinical Tools to Assess Functional Capacity During Risk Assessment Before Elective Noncardiac Surgery : A Scoping Review.

Functional capacity is critical to preoperative risk assessment, yet guidance on its measurement in clinical practice remains lacking. To identify functional capacity assessment tools studied before surgery and characterize the extent of evidence regarding performance, including in populations where assessment is confounded by noncardiopulmonary reasons. MEDLINE, EMBASE, and EBM Reviews (until July 2024). Studies evaluating performance of functional capacity assessment tools administered before elective noncardiac surgery to stratify risk for postoperative outcomes. Study details, measurement properties, pragmatic qualities, and/or clinical utility metrics. 6 categories of performance-based tests and 5 approaches using patient-reported exercise tolerance were identified. Cardiopulmonary exercise testing (CPET) was the most studied tool (132 studies, 32 662 patients) followed by field walking tests (58 studies, 9393 patients) among performance-based tests. Among patient-reported assessments, the Duke Activity Status Index (14 studies, 3303 patients) and unstructured assessments (19 studies, 28 520 patients) were most researched. Most evidence focused on predictive validity (92% of studies), specifically accuracy in predicting cardiorespiratory complications. Several tools lacked evidence on reliability (test consistency across similar measurements), pragmatic qualities (feasibility of implementation), or concurrent criterion validity (correlation to gold standard). Only CPET had evidence on clinical utility (whether administration improved postoperative outcomes). Older adults (≥65 years) were well represented across studies, whereas there were minimal data in patients with obesity, lower-limb arthritis, and disability. Synthesis focused on reported data without requesting missing information. Though several tools for preoperative functional capacity assessment have been studied, research has overwhelmingly focused on CPET and only 1 aspect of validity (predictive validity). Important evidence gaps remain among vulnerable populations with obesity, arthritis, and physical disability. None. (Open Science Framework: https://osf.io/ah7u5).

Prevalence and survival of patients with nasopharyngeal malignancies (C11) (clinical and population-based study)

Introduction. In the 10th revision of the International Classification of Diseases (ICD-10), the code for malignant neoplasms of pharynx (mNN) is C11. These tumors are rare. The state statistics only presents information on morbidity. Data on mortality due to mNN are absent, they are included into the group of other causes of death. The real assessment of the effectiveness of antitumor management of mNN can only be obtained from the population Cancer Registry Database (pCR DB) of the Northwestern federal District of the Russian federation (NwfD Rf) developed by us. This database allows to determine the main analytical values of any parameter included in the case report form. The most reliable criterion of evaluation of the effectiveness of antitumor management is calculation of observed and relative 1-year and corrected 5-year survival rates of patients at the population level and in accordance with international standards.Aim. To perform first in Russia assessment of the effectiveness of antitumor management of mNN with calculation of analytical values including survival (separately for men and women) and detailed characteristics of location and histological structure.Materials and methods. The data of the International Agency for Research on Cancer (IARC), as well as reference books of the p.A. Hertsen moscow Oncology Research Institute and the N.N. petrov National medical Research Center for Oncology were used. Data processing was preformed using mS Excel 2013–2016 and STATISTICA 6.1 licensed software. Survival rates were calculated using modified EuROCARE software. The study was based on the databases of the population cancer registry of Saint petersburg and NwfD Rf developed by us. In total, 950 observations were analyzed. Results. Data obtained during investigation of the incidence and survival rates of mNN confirmed the rarity of this pathology and positive morbidity dynamics, standardized values of which decreased in Russia between 2010 and 2022 by 19.35 %, in NwfD Rf by 27.59 %. The coronavirus pandemic had a significant negative effect on the record keeping. Additionally, between 2010 and 2022 1-year survival of patients with mNN in NwfD Rf increased from 58.5 to 80.6 % (by 22.1 %); 5-year survival increased between 2000 and 2018 from 25.4 to 35.4 % (by 10 %).Conclusion. Analysis of the incidence and survival of patients with malignant neoplasm of rare location can be performed only using a database of population cancer registry of a federal district in compliance with all international rules of its maintenance. unfortunately, currently this is possible only for NwfD Rf.

To speak or not to speak? A secondary data analysis to further explore the context-insensitive avoidance scale.

Inflexibly relying on avoidance of expression may increase and perpetuate pain-related emotional distress in patients with chronic pain. The context-insensitive avoidance (CIA) scale was recently developed to measure the degree to which patients avoid expressing their pain and distress in social situations. This study explored the psychometric properties of the CIA scale in a new sample. This study uses baseline data from a treatment trial for n = 115 patients with chronic pain and co-occurring emotional distress. Reliability and construct and criteria validity were studied using the same instruments as in the original psychometric study and further explored in two new measures. A series of multiple regression analyses were conducted to assess the relationship between the CIA scale and criteria variables compared to the other psychological constructs. The CIA scale showed good reliability. Significant correlations between high scores on the CIA scale and low scores on self-compassion and activity engagement could be replicated. Significant correlations between high scores on the CIA scale and high scores of pain intensity and pain interference could also be replicated. In the exploring part of this study, validity was extended to general problems with emotion regulation and to satisfaction with life in general and contact with friends but not to satisfaction with family, partner, or sexual life. Avoidance of expression was the only significant predictor of pain intensity. This study could replicate acceptable psychometric properties of a scale measuring CIA of expression. As in the original study, avoidance of expression was associated with increased suffering. Clinically, this instrument may be used to identify patients who may otherwise remain in aggravating silence. Theoretically, it introduces the important concept of context sensitivity to the field of chronic pain. Limitations include uncertainty about causal relationships, and that several important social situations were not examined.

Influence of Strain Rate and Temperature on the Multiaxial Failure Stress Locus of a Polyamide Syntactic Foam

This study introduces a comprehensive experimental methodology allowing for the direct measurement of the rate dependent multiaxial response of polymer syntactic foams under combined direct-shear loading. The combined tension-torsion behaviour of a syntactic foam and its rate dependence are investigated for the first time.Dynamic tension-torsion experiments were conducted using a newly developed Tension-Torsion Hopkinson Bar (TTHB) enabling the measurement of the combined tensile-shear response of engineering materials at high rates of strain.The response and multiaxial failure envelope of a polyamide syntactic foam were experimentally measured and analysed to determine the combined influences of stress state, strain rate, and temperature. The multiaxial failure stress locus was defined in both the normal versus shear stress space and the principal stress space, providing a comprehensive characterisation of the behaviour of the material under various loading and environmental conditions.The suitability of existing pressure dependent failure criteria to represent the measured experimental data was also assessed. The Drucker-Prager pressure dependent criterion proved to be effective in capturing the measured quasi-static and dynamic multi-axial stress loci at different temperatures.The effects of temperature, loading rate and stress state on the deformation and failure modes were analysed by means of SEM micrographs of the tested samples.

Validity and Reliability Assessment of a Food and Physical Activity Questionnaire for Adolescents From Low-Income Communities

ObjectiveDevelop and validate an evaluation questionnaire for sixth-12th grade Expanded Food and Nutrition Education Program (EFNEP) participants. DesignFive-step process: domain concept prioritization, question generation, question pretesting, reliability testing, and criterion validity testing. SettingCommunity sites in 4 states and New Jersey EFNEP secondary program data. ParticipantsNineteen sixth-12th graders were interviewed; secondary data included 164 ninth-12th graders. Variables MeasuredContent, face, and criterion validity; internal reliability. AnalysisIterative template analysis to gauge conceptual understanding; exploratory factor analysis with orthogonal Varimax rotation, interitem correlations, and Cronbach α; Spearman correlations and Bland-Altman plots against the Physical Activity Questionnaire for Adolescents and Youth Risk Behavior Survey questions. ResultsFourteen questions with acceptable face validity were developed. One item (handwashing) had a ceiling effect and was removed. Eleven of the remaining 13 items were loaded onto 4 factors. The remaining 2 items were kept because of conceptual relevance. The questionnaire demonstrated acceptable reliability and validity overall, but subscale Cronbach α values ranged from 0.53–0.75. Conclusions and ImplicationsThis 13-item questionnaire was presented to national EFNEP program leaders and was implemented by EFNEP in October 2023. Further research could establish temporal reliability and gold standard criterion validity estimates with a multistate sample of sixth through 12th graders.

Determination of Optimal Corrosion Logging Frequencies for Gas Storage Fields

Summary Many of the existing wells in underground natural gas storage facilities were originally designed to extract hydrocarbons, using construction techniques and practices that differ from modern storage well drilling and completion practices used today. In addition to the age of these wells, their primary flow strings and tubulars may have been exposed to naturally occurring corrosive environments that could have degraded their wall thickness and remaining burst strength. This presents a serious risk of well failure and loss of containment for both the wells and reservoirs of these fields. To address this issue, the Pipelines and Hazardous Materials Safety Administration in its interim final rule recommended that all operators of gas storage facilities determine the reassessment intervals required to maintain the pressure rating and flow isolation properties of the flow string of all gas storage wells. This work presents a novel methodology for establishing the optimal logging frequencies required to maintain the integrity casing wall thickness of the primary flow string, which serves as the leading indicator of casing integrity. In this study, metal loss data from magnetic flux-leakage logs run on existing gas storage wells are collected, vetted, and used to derive a probabilistic distribution of linear corrosion rates. Statistical values of corrosion rate corresponding to severity levels are used to approximate the corrosion rate distribution, allowing for deterministic prediction of remaining burst strength with suitable failure criterion models. The modified ASME B31G model is used to predict casing remaining life as a function of metal loss class and average corrosion rate (ACR). The reliability criterion for establishing fitness-for-service of a corroded casing string is evaluated separately using Monte-Carlo simulation, while reassessment intervals corresponding to a particular casing condition are calculated deterministically. The modeling results with the new approach present predictions of remaining life for four commonly used casing strings as a function of metal loss class and ACR. The results show that the remaining life of a corroded casing can be reasonably estimated as a function of static corrosion rate and metal loss class. The most significant finding is that a brand-new well with an average annual corrosion rate of 1.0% initiating instantaneously upon installation will have an estimated remaining life of 28–32 years. Reassessment intervals are defined based on casing half-life as a function of metal loss class and ACR. A field case study is also presented to demonstrate the successful application of the new methodology in predicting reassessment frequency to mitigate risks from external corrosion mechanisms. The novelty of the proposed approach is in the ability to reasonably predict casing remaining life and safety target levels using derived statistical distributions of linear corrosion rates calculated from magnetic flux leakage logs. This in turn allows operators to confidently establish reassessment intervals for future casing inspection logging to identify corrosion threats in a timely manner that achieves a balance of risk mitigation and cost savings.