Scaling Reliability Research Articles

Leakage Mechanism and Cycling Behavior of Ferroelectric Al0.7Sc0.3N.

Ferroelectric scandium-doped aluminum nitride (Al1-xScxN) is of considerable research interest because of its superior ferroelectricity. Studies indicate that Al1-xScxN may suffer from a high leakage current, which can hinder further thickness scaling and long-term reliability. In this work, we systematically investigate the origin of the leakage current in Al0.7Sc0.3N films via experiments and theoretical calculations. The results reveal that the leakage may originate from the nitrogen vacancies with positively charged states and fits well with the trap-assisted Poole-Frenkel (P-F) emission. Moreover, we examine the cycling behavior of ferroelectric Al0.7Sc0.3N-based FeRAM devices. We observe that the leakage current substantially increases when the device undergoes bipolar cycling with a pulse amplitude larger than the coercive electric field. Our analysis shows that the increased leakage current in bipolar cycling is caused by the monotonously reduced trap energy level by monitoring the direct current (DC) leakage under different temperatures and the P-F emission fitting.

Development and psychometric evaluation of the Implementation Science Research Project Appraisal Criteria (ImpResPAC) tool: a study protocol

IntroductionThe need for quantitative criteria to appraise the quality of implementation research has recently been highlighted to improve methodological rigour. The Implementation Science Research development (ImpRes) tool and supplementary guide...

PENGARUH KUALITAS PELAYANAN TERHADAP KEPUASAN KONSUMEN PADA RESTORAN CEPAT SAJI PIZZA HUT GRAND WISATA

In the fast-food industry, fast-food restaurants that offer pizza also play a significant role. In Indonesia, several brands like Pizza Hut, Domino's Pizza, and Paparons offer various pizza options to consumers. The growth in the number of dining establishments, especially in Bekasi Regency, further solidifies this consumption trend. However, amidst this growth, the number of visitors to Pizza Hut Grand Wisata Bekasi has experienced a year-on-year decline. Factors influencing this decline involve various aspects, including service quality that may not meet consumer expectations. This study aims to analyze the influence of service quality on customer satisfaction at Pizza Hut Grand Wisata Bekasi. In this study, researchers employ a quantitative approach since all data obtained are in the form of direct survey results or distributed questionnaires to customers. Data analysis techniques utilized in this research include scaling techniques, validity tests, and reliability tests. The results of this study affirm that good service quality at Pizza Hut Grand Wisata Bekasi significantly impacts customer satisfaction. While this parameter holds a primary role in shaping satisfaction, it's still essential to consider that otherfactors also contribute to forming consumer perceptions and satisfaction. These findings offer valuable insights for restaurants and similar businesses in their efforts to continuously enhance service quality and customer experience.

Partial randomized benchmarking

In randomized benchmarking of quantum logical gates, partial twirling can be used for simpler implementation, better scaling, and higher accuracy and reliability. For instance, for two-qubit gates, single-qubit twirling is easier to realize than full averaging. We analyze such simplified, partial twirling and demonstrate that, unlike for the standard randomized benchmarking, the measured decay of fidelity is a linear combination of exponentials with different decay rates (3 for two qubits and single-bit twirling). The evolution with the sequence length is governed by an iteration matrix, whose spectrum gives the decay rates. For generic two-qubit gates one slowest exponential dominates and characterizes gate errors in three channels. Its decay rate is close, but different from that in the standard randomized benchmarking, and we find the leading correction. Using relations to the local invariants of two-qubit gates we identify all exceptional gates with several slow exponentials and analyze possibilities to extract their decay rates from the measured curves.

The Effects of Mobile Collaborative Activities in a Second Language Course

This research is designed to explore the areas of collaborative learning and the use of smartphones as a support for collaborative learning through a year-long exploratory multiple case study approach integrating both qualitative and quantitative data analysis. Qualitative exploratory interviews are combined with Multidimensional Scaling Analysis to provide a detailed image of students' mobile use during collaborative activities. The Multidimensional Scaling (MDS) reliability is supported by a second resampling that produced similar results independent of time of subjects. The results are triangulated across the qualitative and quantitative data and key issues are interpreted and discussed. The results indicate that the introduction of mobile access collaborative homework to a second language English class in Japan does have observable effects on students, including changes in use of space, time and method for mobile collaborative homework.

The Orthostatic Hypotension Questionnaire in Swedish tested in patients with parkinsonism.

BackgroundOrthostatic hypotension (OH) is common among older people and in particular in conditions like Parkinson’s disease (PD). The OH Questionnaire (OHQ) has been proposed as a useful patient‐reported assessment tool consisting of the OH Symptom Assessment (OHSA), OH Daily Activity Scale (OHDAS), and a composite score.Aims of the StudyTo translate the OHQ into Swedish and assess its psychometric properties.MethodsFollowing forward–backward translation, the Swedish OHQ was field‐tested (n = 6) for relevance, comprehensibility, and respondent burden. It was then tested regarding scaling assumptions, targeting, reliability, and construct validity in persons with PD (n = 27) and multiple system atrophy (n = 2).ResultsThe Swedish OHQ was considered relevant and easy to use, with a mean completion time of 5.3 min. Scaling assumptions were acceptable for OHSA and OHDAS (corrected item‐total correlations, .30–.67) but not for the total score (.12–.69). Floor/ceiling effects were ≤3.4% and reliability was >.64. Construct validity was supported by expected correlations with the SCOPA‐AUT, RAND‐36, and blood pressure measurements.ConclusionsThe Swedish OHQ was well received, and psychometric results suggest that the OHQ (particularly the OHDAS) is a useful tool for OH assessment in parkinsonian disorders. Further testing in larger samples is needed.

The Turkish version of the Modified Falls Efficacy Scale: reliability and validity from the viewpoint of balance

Background/aim The factors associated with fall-related self-efficacy should be addressed, especially in the elderly. The Modified Falls Efficacy Scale (MFES) is a simple instrument with good scaling properties and reliability. The aim of the present study was to determine the reliability and the validity of the Turkish version of the MFES from the viewpoint of balance.Materials and methods In this study, 164 participants aged >65 years were included. The use of walking aids and assistive devices, history and frequency of falls in the previous year, living environment, and exercise habits were noted. Balance and risk of falling were assessed with the Berg Balance Scale (BBS). A forward-backward translation procedure was used for the Turkish version of the MFES.Results None of the 14 items in the MFES were modified. The Turkish version of the MFES has excellent internal consistency (Cronbach’s alpha, 0.978) and reliability (interclass correlation coefficient, 0.928–0.982), and its construct validity was supported by its ability to distinguish between the groups with respect to fall-risk factors and balance. According to the BBS scores, the high-fall-risk group had lower MFES scores than the moderate- and low-fall-risk groups (χ2 = 34.153, P = 0.001).Conclusion The Turkish version of the MFES is a sensitive instrument for evaluation of fall-related confidence while carrying out indoor/outdoor activities. It also predicts falls, reduced physical activity, balance and mobility problems, and restricted social participation and daily living activities.

Extracting Atomic Defect Properties From Leakage Current Temperature Dependence

In modern electronic devices, a variety of novel materials have been introduced such as transition metal oxides, chalcogenides, ferroelectric, and magnetic materials. The electrical response of such materials, used also as active layers, is strongly affected by atomic defects, which affect device performances, variability, and reliability. Extracting the defect properties (i.e., density, energy, and atomic nature) is, thus, crucial to both engineer the performances of electron devices and correctly project their scaling potential and reliability. In this paper, we propose a simple method to extract the atomic properties of defects from the thermal activation energy of the leakage current using a charge trapping relaxation model.

Development of a modular single-phase grid-tie inverter system for fuel-cell power generation

To enhance the conversion efficiency and electrical reliability of the low-voltage fuel-cell (FC) power generation system, this paper proposes a modular single-phase grid-tie inverter system equipped with a power management and remote monitoring interface. In this system, each single power module is composed of three single-stage quasi-resonant (QR) flyback current-source inverters that are connected in parallel, and all the power modules are connected in parallel to achieve flexible power scaling and load sharing. The proposed grid-tie inverter system possesses a power management unit (PMU) and can be integrated with a home energy management system (HEMS). An experiment was conducted to verify the feasibility of the proposed concept, in which five power modules were assembled to form a 1-kW high-efficiency grid-tie inverter system, which was modulated through the PMU. The results showed satisfactory load-sharing characteristics between the parallel-connected power modules. The peak efficiency for each power module and the overall power generation system are about 94.5 and 90%, respectively. The proposed system exhibits flexible power scaling, load sharing, and high reliability.

Precarious employment in Chile: psychometric properties of the Chilean version of Employment Precariousness Scale in private sector workers.

The purpose of this study is to perform a psychometric analysis (acceptability, reliability and factor structure) of the Chilean version of the new Employment Precariousness Scale (EPRES). The data is drawn from a sample of 4,248 private salaried workers with a formal contract from the first Chilean Employment Conditions, Work, Health and Quality of Life (ENETS) survey, applied to a nationally representative sample of the Chilean workforce in 2010. Item and scale-level statistics were performed to assess scaling properties, acceptability and reliability. The six-dimensional factor structure was examined with confirmatory factor analysis. The scale exhibited high acceptability (roughly 80%) and reliability (Cronbach's alpha 0.83) and the factor structure was confirmed. One subscale (rights) demonstrated poorer metric properties without compromising the overall scale. The Chilean version of the Employment Precariousness Scale (EPRES-Ch) demonstrated good metric properties, pointing to its suitability for use in epidemiologic and public health research.

Descriptive analytics: its power to test the applicability of cross-national scales in exploratory studies

Conventional methodology for validating measures in consumer research relies on structural equation modeling. But, this procedure requires a fairly large sample size and a clear conceptualization of the relationship between individual items and various scale dimensions. Neither of these requirements may be met in exploratory cross-national studies. Hence, this paper addresses scale validation issues in exploratory cross-national research, where sample size is a major concern. Specifically, it uses cross-national data on the vanity measure as an exemplar and a battery of descriptive analytics to show how to assess scaling assumptions, reliability, and dimensionality of consumer behavior measures. The scale validation procedure the authors describe in this paper has implications for researchers who use multi-item rating scales as measures of consumer behavior constructs. Keywords: cross-cultural, scale validation, exploratory research, cross-national, scale applicability JEL Classification: L1, L13, D11, D12, M31

Intrinsic Tailing of Resistive States Distributions in Amorphous HfO<sub><italic>x</italic></sub> and TaO<sub><italic>x</italic></sub> Based Resistive Random Access Memories

We report on the ineffectiveness of programming oxide-based resistive random access memory (OxRAM) at low current with a program and verify algorithm due to intrinsic relaxation of the verified distribution to the natural state distribution obtained by single-pulse programming without verify process. Based on oxygen defect formation thermodynamics and on their diffusion barriers in amorphous HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> and TaO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> , we describe the intrinsic nature of tailing of the verified low resistive state and high resistive state distributions. We introduce different scenarios to explain fast distribution widening phenomenon, which is a fundamental limitation for OxRAM current scaling and device reliability.

Update on the OMERACT Magnetic Resonance Imaging Task Force: Research and Future Directions

Magnetic resonance imaging (MRI) provides an important biomarker across a range of rheumatological diseases. At the Outcome Measures in Rheumatology (OMERACT) 11 meeting, the MRI task force continued its work of developing and improving the use of MRI outcomes for use in clinical trials. The breadth of pathology in the Rheumatoid Arthritis MRI Score has been strengthened with further work on the development of a joint space narrowing score, and a series of exercises presented at OMERACT 11 demonstrated good reliability and construct validity for this assessment. Understanding the importance of residual inflammation after RA treatment remains a major focus of the group's work. Analyses were presented on defining the level of synovitis (using MRI scores of a single hand) that would predict absence of erosion progression. The development of the OMERACT Hand Osteoarthritis MRI score has continued with substantial work presented on its iterative development, including pathology definition, scaling, and subsequent reliability of the score. Optimizing the role of MRI as a robust biomarker and surrogate outcome remains a priority for this group.

Design challenges in cross-national VAAs: the case of the EU Profiler

This paper analyses the design of the EU Profiler, the first truly cross–national VAA. We assess the convergent validity and scaling reliability of the low–dimensional models that are used to represent differences between parties and users. Convergent validity of the party positions in the EU Profiler is moderate to high, but scaling reliability is low for most of the issue dimensions included. We examine whether these problems are related to the EU Profiler's cross–national nature. The EU Profiler integrates the positions of parties from all over Europe into one pan–European model, even though students of European politics emphasise that there are structural differences between party competition in Central and Eastern Europe and Western Europe. We find that the EU Profiler performs better in terms of scaling reliability in Western European party systems than in Central and Eastern European party systems. In addition, there are substantive differences between individual countries.

Modification and validation of the Revised Diabetes Knowledge Scale

To develop a simplified true/false response format of the Revised Diabetes Knowledge Scale and assess scaling assumptions, reliability and validity of the binary response format (the Simplified Diabetes Knowledge Scale) and compare with a multiple-choice version. Ninety-nine respondents attending an outpatient clinic completed the multiple-choice version of the Revised Diabetes Knowledge Scale and the simplified version of the Revised Diabetes Knowledge Scale. The response patterns and psychometric properties of both questionnaires were assessed in order to test the construct validity of the simplified version. The mean age of the respondents was 57 years (range 21-83 years) and 64% were men. Respondents attained an average score of 65% on the Simplified Diabetes Knowledge Scale, compared with 62% on the Revised Diabetes Knowledge Scale. Overall, the Simplified Diabetes Knowledge Scale appeared to be somewhat easier to complete compared with the Revised Diabetes Knowledge Scale, as indicated by the number of missing responses. The Simplified Diabetes Knowledge Scale provides researchers with a brief and simple diabetes knowledge questionnaire with favourable psychometric properties. The scale may require further updating to include other items relevant to diabetes education. This simplified version will now undergo translation and validation for use among minority ethnic groups resident in the UK.

Psychometric evaluation of the SF-36 (v.2) questionnaire in a probability sample of Brazilian households: results of the survey Pesquisa Dimensões Sociais das Desigualdades (PDSD), Brazil, 2008

BackgroundIn Brazil, despite the growing use of SF-36 in different research environments, most of the psychometric evaluation of the translated questionnaire was from studies with samples of patients. The purpose of this paper is to examine if the Brazilian version of SF-36 satisfies scaling assumptions, reliability and validity required for valid interpretation of the SF-36 summated ratings scales in the general population.Methods12,423 individuals and their spouses living in 8,048 households were selected from a stratified sample of all permanent households along the country to be interviewed using the Brazilian SF-36 (version 2). Psychometric tests were performed to evaluate the scaling assumptions based on IQOLA methodology.ResultsData quality was satisfactory with questionnaire completion rate of 100%. The ordering of the item means within scales clustered as hypothesized. All item-scale correlations exceeded the suggested criteria for reliability with success rate of 100% and low floor and ceiling effects. All scales reached the criteria for group comparison and factor analysis identified two principal components that jointly accounted for 67.5% of the total variance. Role emotional and vitality were strongly correlated with physical and mental components, respectively, while social functioning was moderately correlated with both components. Role physical and mental health scales were, respectively, the most valid measures of the physical and mental health component. In the comparisons between groups that differed by the presence or absence of depression, subjects who reported having the disease had lower mean scores in all scales and mental health scale discriminated best between the two groups. Among those healthy and with one, two or three and more chronic illness, the average scores were inverted related to the number of diseases. Body pain, general health and vitality were the most discriminating scales between healthy and diseased groups. Higher scores were associated with individuals of male sex, age below 40 years old and high schooling.ConclusionsThe Brazilian version of SF-36 performed well and the findings suggested that it is a reliable and valid measure of health related quality of life among the general population as well as a promising measure for research on health inequalities in Brazil.

Childbirth experience questionnaire (CEQ): development and evaluation of a multidimensional instrument

BackgroundNegative experiences of first childbirth increase risks for maternal postpartum depression and may negatively affect mothers' attitudes toward future pregnancies and choice of delivery method. Postpartum questionnaires assessing mothers' childbirth experiences are needed to aid in identifying mothers in need of support and counselling and in isolating areas of labour and birth management and care potentially in need of improvement. The aim of this study was to develop and evaluate a questionnaire for assessing different aspects of first-time mothers' childbirth experiences.MethodsChildbirth domains were derived from literature searches, discussions with experienced midwives and interviews with first-time mothers. A draft version of the Childbirth Experience Questionnaire (CEQ) was pilot tested for face validity among 25 primiparous women. The revised questionnaire was mailed one month postpartum to 1177 primiparous women with a normal pregnancy and spontaneous onset of active labor and 920 returned evaluable questionnaires. Exploratory factor analysis using principal components analysis and promax rotation was performed to identify dimensions of the childbirth experience. Multitrait scaling analysis was performed to test scaling assumptions and reliability of scales. Discriminant validity was assessed by comparing scores from subgroups known to differ in childbirth experiences.ResultsFactor analysis of the 22 item questionnaire yielded four factors accounting for 54% of the variance. The dimensions were labelled Own capacity, Professional support, Perceived safety, and Participation. Multitrait scaling analysis confirmed the fit of the four-dimensional model and scaling success was achieved in all four sub-scales. The questionnaire showed good sensitivity with dimensions discriminating well between groups hypothesized to differ in experience of childbirth.ConclusionThe CEQ measures important dimensions of the first childbirth experience and may be used to measure different aspects of maternal satisfaction with labour and birth.

Validity and reliability of the European Organization for Research and Treatment in Cancer Quality of Life Questionnaire (EORTC QLQ): experience from Kuwait using a sample of women with breast cancer

BACKGROUND AND OBJECTIVES:Although the EORTC QLQ-C30 and its breast-specific module (BR-23) are widely used instruments, the few reports on their psychometric characteristics from Arab and neighboring countries involved limited analyses. Our objective was to assess the psychometric characteristics of both questionnaires using the responses of a larger sample of Arab women.METHODS:Participants were consecutive clinic attendees at the Kuwait Cancer Control Center. The indices assessed were alpha coefficients, item-internal consistency (IIC), item-discriminant validity (IDV), and known-groups validity.RESULTS:The 348 women were aged 48.3 (10.3) years. The intra-class correlation for the test-retest statistic and the internal consistency values for the multi-item scales were >0.7 alpha. With the exception of the pain subscale, all items met the IIC criterion of >0.4 correlation with the corresponding scale. For IDV, the BR-23 performed better than the QLQ-C30. The scale scores discriminated between patients at different disease stages, and between sick and well populations.CONCLUSION:With the exception of the pain subscale, the Arabic version of the questionnaires is psychometrically sound.

Testing scaling assumptions, reliability and validity of medical outcomes study short-form 36 health survey in psoriatic arthritis

The Medical Outcome Survey short-form 36 (SF-36) is widely used in studies of PsA. We test the fundamental scaling assumptions for the validity of SF-36 eight scales and two summary scores in PsA. We tested the five scaling criteria according to the International Quality of Life Assessment project and the validity of the physical component summary (PCS) and mental component summary (MCS) scores. The construct validity for SF-36 in PsA was evaluated. A total of 168 PsA subjects according to CASPAR criteria (46.4% females) with SF-36 data were analysed. The mean (S.D.) age and duration of illness were 47.7 (11.9) and 8.4 (7.3) years. PsA subjects had poorer quality of life as compared with normal population. The norm-based mean (S.D.) PCS and MCS were 31.6 (14.2) and 45.2 (12.7), respectively. The Pearson's correlations between an item and its hypothesized scale were all >0.4, indicating item internal consistency. All item-own scale correlations exceed item-other scale correlations, except minor scaling failure in general health. The Cronbach's alpha-coefficients of internal reliability (Cronbach's alpha) were all above the standard value of 0.7, indicating a unique concept in each scale. Principal component analysis explained 69.4 and 73.7-99.9% of the total variance and total reliable variance in all SF-36 scales. The two-factor model is supported. PsA had high impact on quality of life. All eight scales and two summary scores of SF-36 satisfied criteria for scaling assumption. SF-36 is a valid measurement for quality of life in PsA. The reporting of PCS and MCS in PsA is supported.

The development of patient-reported outcome indices for multiple sclerosis (PRIMUS)

Background Complex diseases such as multiple sclerosis (MS) present dilemmas over the choice of patient-reported outcome measures as no single scale can inform on all types of MS impact from the patient’s perspective. Objective To develop an outcome tool, the Patient-Reported Indices for Multiple Sclerosis (PRIMUS), to assess MS symptoms, activities, and quality of life. Methods PRIMUS content was derived from qualitative interviews with UK MS patients and checked by clinical experts. Semi-structured cognitive debriefing interviews assessed scale face and content validity. PRIMUS scaling properties, reliability, and construct validity were assessed by a test–retest postal survey. Results Cognitive debriefing interviews (n = 15) demonstrated scale clarity, relevance, and comprehensiveness. The postal survey was completed by 135 patients with MS. After removal of misfitting items and those exhibiting differential item functioning, all scales fitted the Rasch model, confirming unidimensionality. For all scales, test–retest reliability exceeded 0.80. Scale scores were related to perceived MS severity, general health, and symptoms of depression. Moderate correlations were observed between PRIMUS and Nottingham Health Profile scores. Conclusions Clinicians and researchers can have confidence in scores obtained by respondents on the PRIMUS. The PRIMUS will aid the assessment of the impact of MS from the patient’s perspective.