Reliability Of Code Research Articles

Does Being In-Person Matter? Demonstrating the Feasibility and Reliability of Fully Remote Observational Data Collection.

Many conventional research methods employed in randomized controlled trials were not possible during the height of the COVID-19 pandemic. In particular, behavioral observations are nearly universally gathered in-person. Observational methods are valued for the rich, informative data they produce in comparison to non-observational methods and are a cornerstone of parenting and family research. COVID provided the opportunity to, and indeed necessitated, the transition to fully remote observation. However, little to no studies have investigated whether remotely collected observational data are methodologically sound. This paper assesses the feasibility of remote data collection by describing the transition between in-person and fully remote observational data collection during a Sequential, Multiple Assignment, Randomized Trial (SMART) of a parenting program that took place both before and during the pandemic. Using mixed-methods data from coders, the overall quality of video-recorded data collected both before and during COVID was examined. Coder reliability over time was assessed with intraclass correlation coefficients. Results suggest that the frequency of audio problems, the severity of visual problems, and the level of administration challenges decreased after transitioning to remote data collection. Additionally, coders showed good to excellent reliability coding remotely collected data, and reliability even improved on some measured tasks. Although challenges to remote data collection exist, this study demonstrated that observational data can be collected feasibly and reliably. As observational data collection is a key method to assess parenting practices, these findings should improve researcher confidence in utilizing remote observational methods in prevention science.

Academic Self-problems of Candidate Teachers of Native Language: “I am not sure what or how to learn.” But I must be sure of what I can teach.”

Academic self-concept is an individuals’ self-definition using their experiences in the educational process or their views on their own skills and interests. This study aims to determine the academic self-perception of teacher candidates of native language. This study was conducted with a qualitative approach in a phenomenological design. The study group consisted of 10 female and 6 male native language teacher candidates at a university located in the eastern part of Turkey. During the data collection process, semi-structured interviews were conducted with open-ended questions, the data collected with a voice recorder was converted into a written text. Participant views were subjected to content analysis. The first, last, and focus codings were completed for “coder reliability;” and an external controller was also used. In this study, the data source was diversified with reminder notes and observation reports for stability and transparency. The findings revealed that most participants had high verbal abilities and interests, and weak numerical abilities and interests. Additionally, the views that they were unable to make the right choices in line with their abilities and interests and therefore could not achieve their academic self-concept and goals are remarkable.

Identifying the dimensions of gender justice in the Iranian Ministry of Sport and Youth

In modern times, sports have attracted the attention of different societies. Social, economic and political functions are one of the reasons. In Iran, the role of the Ministry of Sports and Youth is very important in managing sports in the country. Justice has been supposedly one of the pillars of ethical management in organizations, along with performance improvement. One example of justice in organizations is gender justice. The aim of this study was to provide valuable information to sports activists in the country by identifying the dimensions of gender justice in the Ministry of Sports and Youth and identify ways to expand gender justice according to employees' perceptions. The current research is practical in terms of purpose and qualitative in terms of method, employing a thematic analysis strategy. The sample consisted of 7 management experts and sociologists who had studied, researched, or gained experience in the field of the present study (gender justice in organizations). The researchers used a semi-structured interview, which is suitable for qualitative research in terms of flexibility and depth. The "Inter Coder Reliability (ICR)" method was used to measure the reliability of the interviews conducted. The data were coded using MAXQDA2018 software. The results showed that perceptions of gender justice include 3 main themes (distributive justice, procedural justice and interactional justice) and 19 sub-themes. The expansion of gender justice in the Ministry of Sports and Youth, as the country's sports policy organization, can seemingly be effective in improving performance. It also has positive social and cultural effects on all sports areas of the country.

Presenting a Model of Work-Family Conflict Management Regarding the Non-Clinical Employees of Iran University of Medical Sciences During COVID-19 Pandemic

Background: Conflicts between work and family wants are inevitable in organizations and families. This, in turn, creates psychological problems in people's personal and working life. The aim of this study is to present a model of work-family conflict management among employees of Iran University of Medical Sciences during COVID-19 pandemic.
 Methods: This was a qualitative study conducted in 2021. The statistical population of the research included 14 thematic and executive experts who were selected with judgmental-purposive method. The analytical model of the research was deductive-inductive and based on the qualitative method of thematic analysis. Data were collected by document method and through in-depth and semi-structured interviews with experts of Iran University of Medical Sciences. The content validity of the research model was 85%. Retest reliability was 70% and coder reliability was 87%.
 Results: After five stages of content analysis, 67 basic themes, 7 comprehensive themes (family stress stimulus ( 3 themes)), supportive job variables (11 themes), moderating variables (7 themes), stress management (12 themes), negative consequences (17 themes), positive outcomes (2 themes), (work stress stimuli(15 themes)) were counted and added. Finally, a work-family for the staff of Iran University of Medical Sciences was designed.
 Conclusion: According to the current research model, work-family conflict management in the period of COVID-19 requires a new way of working. It should be independent, flexible and compatible with individual conditions and preferences of employees more than before. Considering the importance of the negative consequences of work-family conflict, the vice-chancellor of management and resource development in the university can use the model presented in this research to prepare training programs needed by employees. He can also manage the negative consequences of work-family conflict and develop support and counseling programs needed by employees to be used during COVID-19 pandemic.

Psychosocial context and food healthiness in top-grossing American films.

Healthy eating is shaped by the context. To understand how healthy eating is modeled in popular media, this systematic analysis quantified which contextual factors, character behaviors, and character demographics were associated with food healthiness in popular movies. Two researchers content-coded the contextual factors, character behaviors, and character demographics depicted across 9,093 foods in 244 top-grossing Hollywood movies released from 1994-2018. Food healthiness was calculated using the Nutrient Profile Index (0 = least healthy, 100 = healthiest) and coder reliability was assessed. Mixed effects regression models tested whether food healthiness was associated with contextual factors (e.g., geographic locations, social consumption situations, celebrations, foreground placement), character behaviors (actual consumption, food evaluations), and character demographics. Confirming six preregistered hypotheses (all p < .001), foods were less healthy when they were in American versus non-American settings (95% CI: Cohen's d = .29-.39), part of social consumption situations (d = .19-.28) and celebrations (d = .04-.17), and in the foreground versus background (d = .15-.24). The foods that characters actually consumed (d = .30-.42) and evaluated positively (vs. negatively, d = .37-.76) were also less healthy. However, disconfirming a gender hypothesis, female characters did not consume healthier foods than males (d = -.11-.13, p = .45). Top-grossing Hollywood movies depict different contexts and different character behaviors for healthier versus less healthy foods. Research is needed to understand whether depicting healthy foods in different contexts impacts viewers' beliefs and behavior. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Using natural language processing and machine learning to replace human content coders.

Content analysis is a common and flexible technique to quantify and make sense of qualitative data in psychological research. However, the practical implementation of content analysis is extremely labor-intensive and subject to human coder errors. Applying natural language processing (NLP) techniques can help address these limitations. We explain and illustrate these techniques to psychological researchers. For this purpose, we first present a study exploring the creation of psychometrically meaningful predictions of human content codes. Using an existing database of human content codes, we build an NLP algorithm to validly predict those codes, at generally acceptable standards. We then conduct a Monte-Carlo simulation to model how four dataset characteristics (i.e., sample size, unlabeled proportion of cases, classification base rate, and human coder reliability) influence content classification performance. The simulation indicated that the influence of sample size and unlabeled proportion on model classification performance tended to be curvilinear. In addition, base rate and human coder reliability had a strong effect on classification performance. Finally, using these results, we offer practical recommendations to psychologists on the necessary dataset characteristics to achieve valid prediction of content codes to guide researchers on the use of NLP models to replace human coders in content analysis research. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

A Pattern for Assessing the Health System Governance in the Islamic Republic of Iran: A Thematic Analysis

Background: Governance in the health system is not just a vision, or a model for delivering services, but a key element in planning, implementing and evaluating activities to improve health. The main purpose of this study was to design a pattern for assessing Iran's Health System Governance.&#x0D; Methods: The present study was descriptive in terms of purpose, qualitative in terms of application, and qualitative in terms of data type, which was conducted based on thematic analysis and deductive-inductive approach. 14 health system experts were selected through non-random-purposive sampling. To calculate reliability, test-retest reliability and coder reliability were used, which were 70 and 87 %, respectively. Also, Waltz and Basel method was used to assess the content validity of the extracted indices which was 85 %.&#x0D; Results: After 6 stages of thematic analysis, 137 basic themes, 15 organizing themes and 5 comprehensive themes (health system accountability, health system participation, health system policy formulation, health system service provision, health system efficiency and quality) were obtained, and finally, a model for assessing the governance of the health system in the Islamic Republic of Iran was designed. Organizational accountability included 7 themes, ethical accountability, 9, and legal accountability included 6 .Financial accountability included 8 basic themes, and efficiency and quality, 10 basic themes. Implementation included 8 themes, comprehensiveness, 4, reporting, 12, and transparency, 6. Structural policy included 23 themes, social inclusion and justice policy, 6, and fiscal policy included 11 basic themes. Medical services included 4 themes, financial services, 7, human services and human rights, 9, and information and technology services included 7 basic themes. In this pattern, participation and policy formulation were considered input, and accountability, efficiency and quality and service delivery were considered output.&#x0D; Conclusion: Lack of a clear definition for an appropriate interdepartmental cooperation, Lack of meritocracy, having a guild oriented attitude, conflict of interests, not using a policymaking approach based on a collective evidence and wisdom are among the shortcomings of the current health system governance. In addition, healthcare costs imposed on people are too high.

Performance of a Supervisor Observational Coding System and an Audit and Feedback Intervention.

Workplace-based clinical supervision is common in community based mental health care for youth and families and could be a leveraged to scale and improve the implementation of evidence-based treatment (EBTs). Accurate methods are needed to measure, monitor, and support supervisor performance with limited disruption to workflow. Audit and Feedback (A&F) interventions may offer some promise in this regard. The study-a randomized controlled trial with 60 clinical supervisors measured longitudinally for 7 months-had two parts: (1) psychometric evaluation of an observational coding system for measuring adherence and competence of EBT supervision and (2) evaluation of an experimental Supervisor Audit and Feedback (SAF) intervention on outcomes of supervisor adherence and competence. All supervisors recorded and uploaded weekly supervision sessions for 7months, and those in the experimental condition were provided a single, monthly web-based feedback report. Psychometric performance was evaluated using measurement models based in Item Response Theory, and the effect of the SAF intervention was evaluated using mixed-effects regression models. The observational instrument performed well across psychometric indicators of dimensionality, rating scale functionality, and item fit; however, coder reliability was lower for competence than for adherence. Statistically significant A&F effects were largely in the expected directions and consistent with hypotheses. The observational coding system performed well, and a monthly electronic feedback report showed promise in maintaining or improving community-based clinical supervisors' adherence and, to a lesser extent, competence. Limitations discussed include unknown generalizability to the supervision of other EBTs.

Thermal-hydraulic analysis of light water reactors under different steady-state operating conditions, Part 1: Boiling water reactor

The steady-state thermal-hydraulic analysis of the core of the Boiling Water Reactor (BWR/6) at nominal operating conditions is presented in this paper. The BWR/6 is produced by General Electric USA. The analysis' goal is to keep the thermal safety margin under control and the core integrity intact under steady-state operating conditions. The effects of operating conditions such as power distribution, power level, and coolant mass flow rate on the pro- posed core's performance are investigated. For this purpose, the one-dimensional computer code MITH was used. The code's reliability was tested using the General Electric benchmark 3579 MW reactor. Two-channel models were tested (the average and the hot channel). Ther- mal-hydraulic parameters such as fuel-centerline, fuel-surface, outer clad surface and coolant temperature, critical and actual local heat flux, critical and minimum critical heat flux ratio and pressure drop are evaluated along the tested channels. Temperatures, as well as actual and critical heat flux distribution profiles, were obtained. The tested operating conditions had a significant influence on these parameters, and also on the thermal-hydraulic performance. The obtained results are in good agreement with the data from the tested core. The obtained results are well within the safety margins. The good agreement between tested reactor data and MITH code calculation concerning the reactor demonstrates the reliability of the analysis methodology from a thermal-hydraulic perspective.

Gravity measurement to probe the depth of African-continental crust over a north-south profile: theory and modeling

Based upon gravity measurements and calculations, the depth of the African continental crust is estimated. Taking as constraints the mass and radius of earth, and measured gravity, this theoretical method explores the use of gravitational potential to calculate the absolute gravity at three locations in Africa (e.g., Cape Town at latitude -34o, central Africa at latitude 0, and Benghazi at latitude 32o). The computational method uses as input a continental crust density ρ1 = 2.65–2.75 g/cm3 while compromising the oceanic crust density ρ2 to maintain the average crust density of the planet fixed at <ρ12> = 2.60 g/cm3. Crustal depth is assumed uniform around the earth and kept as a free parameter to adjust for the best fitting of gravity but using values of less than 100 km. A solid angle αo is a solid angle whose vertex is at the center of earth used to separate continental and oceanic crusts (αo = 10o, 20o, 35o). The results obtained for the continental crust were H = 36 km near continental edges at both Benghazi and Cape Town, whereas H = 44.4 km at the center of continent. These results are in excellent agreement with those reported by Tedla and coworkers (H = 39 ± 5 km) using an Euler deconvolution method. Our theoretical results from the developed code are also corroborated by results of numerical forward modeling supporting our code's reliability for further geoscience explorations.

Türkçe Öğretmenlerinin Teknoloji Kullanımına ve Teknoloji Destekli Türkçe Öğretiminin Etkililiğine Dair Görüşleri

Bu çalışmanın amacı Türkçe öğretmenlerinin derslerinde teknolojiyi kullanma durumlarını ve teknoloji destekli Türkçe öğretiminin etkililiğine dair görüşlerini belirlemektir. Nitel araştırma yöntemine göre tasarlanan bu çalışmada veri toplama aracı olarak görüşme tekniği kullanılmıştır. Uzman görüşleri ve pilot uygulama sonrasında, görüşme formunda 16 soruya yer verilmiştir. Çalışma grubunu gönüllü olan 12 Türkçe öğretmeni oluşturmaktadır. Katılımcıların tamamı teknolojik altyapısı olan okullarda görev yapmaktadır. Verilerin analizinde içerik analizi yapılmıştır. Analizin güvenirliği için kodlayıcı güvenirliğine bakılmıştır. Çalışma sonucunda öğretmenlerin çoğunluğunun teknoloji kullanma konusunda kendilerini yetersiz gördüğü ve derslerinde teknolojiyi orta düzeyde kullandıkları görülmüştür. Öğretmenler programdaki teknoloji ile ilgili hedeflerden haberdar olduklarını belirtmişlerdir. Teknoloji, öğretmenler açısından öğretim sürecinde kolaylık sağlamaktadır. Teknoloji Türkçe öğretim sürecinde özellikle dinleme becerisi üzerinde daha çok etkili olmaktadır. Az sayıda öğretmen ise teknolojinin okuma ve konuşma becerisinin gelişiminde de etkili olduğunu belirtmiştir.

Behavioral Assessment of Hearing in 2- to 7-Year-Old Children: Evaluation of a Two-Interval, Observer-Based Procedure Using Conditioned Play-Based Responses.

Purpose It is challenging to collect reliable behavioral data from toddlers and preschoolers. Consequently, we have significant gaps in our understanding of how auditory development unfolds during this time period. One method that appears to be promising is an observer-based procedure that uses conditioned, play-based responses (Bonino & Leibold, 2017). In order to evaluate the quality of data obtained with this method, this study presented a suprathreshold signal to determine the number of trials 2- to 7-year-old children could complete, as well as the associated hit rate and observer confidence. Method Participants were 23 children (2-7 years old). Children were taught to perform a play-based motor response when they detected the 1000-Hz warble tone signal (at 30 dB SPL). An observer evaluated children's behavior using a 2-interval, 2-alternative testing paradigm. Testing was terminated after 100 trials or earlier, if signs of habituation were observed. Results Data were successfully collected from 22 of the 23 children. Of the 22 children, all but 1 child completed 100 trials. Overall hit rate was high (0.88-1.0; M = 0.94) and improved with listener age. Hit rate was stable across the test session. Strong agreement was seen between the correctness of the response and the observer's confidence in the judgment. Conclusion Results of this study confirm that the 2-interval, observer-based procedure described in this article is a powerful tool for measuring detection and discrimination abilities in young children. Future research will (a) evaluate coder reliability and (b) examine stability of performance across a test session when the signal intensity is manipulated. Supplemental Material https://doi.org/10.23641/asha.8309273.

Pain Expressions in Dementia: Validity of Observers\u2019 Pain Judgments as a Function of Angle of Observation

Facial expressions of pain are important in assessing individuals with dementia and severe communicative limitations. Though frontal views of the face are assumed to allow for the most valid and reliable observational assessments, the impact of viewing angle is unknown. We video-recorded older adults with and without dementia using cameras capturing different observational angles (e.g., front vs. profile view) both during a physiotherapy examination designed to identify painful areas and during a baseline period. Facial responses were coded using the fine-grained Facial Action Coding System, as well as a systematic clinical observation method. Coding was conducted separately for panoramic (incorporating left, right, and front views), and a profile view of the face. Untrained observers also judged the videos in a laboratory setting. Trained coder reliability was satisfactory for both the profile and panoramic view. Untrained observer judgments from a profile view were substantially more accurate compared to the front view and accounted for more variance in differentiating non-painful from painful situations. The findings add specificity to the communications models of pain (clarifying factors influencing observers’ ability to decode pain messages). Perhaps more importantly, the findings have implications for the development of computer vision algorithms and vision technologies designed to monitor and interpret facial expressions in a pain context. That is, the performance of such automated systems is heavily influenced by how reliably these human annotations could be provided and, hence, evaluation of human observers’ reliability, from multiple angles of observation, has implications for machine learning development efforts.

Development of the therapeutic language coding system (SICOLENTE): Reliability and construct validity.

Since the use of language is a core aspect of psychotherapy, its study requires instruments that allow for further research. The aim of this study is to present an observational instrument capable of analyzing the language used in psychotherapeutic settings, both by therapists and clients. The SICOLENTE instrument was applied to two different samples: The Three Approaches to Psychotherapy film and a naturalistic sample. 7710 utterances from 31 sessions (three from the demonstration film and 28 from a naturalistic setting) were coded. Two studies were conducted: in the first study, inter and intra coder reliability (dimension and category levels) and Generalizability theory analyzes were assessed, whilst in the second study, construct validity was tested with several hypotheses. The final instrument resulted in 20 categories with three dimensions: Conversational Act (7 categories), Therapeutic topic (6 categories) and Content (7 categories). The three dimensions showed excellent inter and intra coder reliability and the generalizability coefficients were excellent. Out of the 24 validity hypothesis proposed,19 were accepted. The finding suggests that the SICOLENTE is a reliable and valid instrument that can be applied to investigate the performance of various theoretical models. Its three dimensional structure gives it the flexibility to be able to carry out macroscopic or microscopic language research.

Adapting a Small Group Communication Quality Assessment to New Contexts

Objectives: Small group learning is a well-established medical education strategy for cultivating essential communication skills. Yet, how best to measure communication quality in these groups remains understudied. This study aimed to adapt a communication assessment to medical education small group settings. Methods: This was an observational study of Preclinical Medical Humanities group discussions. Audio-recordings of 12 sessions (3 groups; n=22 students and 3 facilitators) were analyzed using Communication Quality Analysis. Three coders assessed communication quality by assigning numeric scores based on how well participants accomplished communication goals within five domains: content, engagement, relationship, emotion and identity. Coder reliability was assessed using intra-class correlations. Variance components were assessed using a generalized linear model.Results: High inter-rater reliability was established for each of five communication quality domains (ICC range 0.875 to 0.98). Variability in content, emotion, and engagement domains was primarily driven by the individual subjects (nested within the three communication groups)–accounting for 49%, 57% and 78% of the variability respectively; relational and identity domain score variability was accounted for by duration of class (accounting for 66% and 47% of the variability, respectively). Considerable variability was observed between participants, suggesting that the assessment is sensitive enough to detect nuanced differences between participants.Conclusions: Our study shows that CQA is reliable when adapted to medical education small groups.With further refinement, CQA provides an important measure that could be used in medical education to evaluate the impact of novel curricular activities or varied facilitation techniques on communication quality and other educational outcomes.

The Recognition and Behavior Management of Students With Talented and Gifted in an Inclusive Education Environment

During student development, enriching academic and psychosocial activities in accordance with different educational needs of students is important. This study aims to identify primary school teachers’ opinions in Turkey, Czech Republic, Italy, and Germany. The opinions of teachers were investigated and compared on the individual skills, interests, intelligence, and abilities of students in the inclusive education environment with talented and gifted students. Moreover, methods, techniques and strategies they implemented in behavioral management, development and the bonding of the students to each other were analyzed. The study is a descriptive qualitative research. Layered sampling was used from the purpose sampling methods. The study group consisted of 248 elementary school teachers. In data analysis, content analysis was used. To ensure validity and reliability of the study, the coder reliability coefficient, the expert opinion, the confirmability strategy techniques were used. In Czech Republic, Turkey and Italy the teaching dimension for determining the students' interests, abilities and intelligence was emphasized, while Germany the dimensions of co-operation with parents and stakeholders was highlighted. Teachers participating in the development of positive behavior prioritised the communication process, stimulating educational activities in the management of unwanted behavior and the bonding of students with each other. Teachers' educational effectiveness-based responses in relation to the management of students' interests, skills and intelligence, development and behaviour revealed that teachers cannot parse the approaches that correspond to different problem areas. It was observed that there were not enough applications to contribute to the psychosocial development of students with different developmental characteristics.

Comparing Live and Video Observation to Assess Early Parent-child Interactions in the Home

Observation is the ‘gold standard’ for assessing parent-child behavior, however few studies have compared coding live, in real time, versus coding from videotapes in terms of their achievable levels of coder reliability within the field of parent programme research. This is important for practitioners and researchers for whom decisions might be influenced by time and financial constraints, but where outcomes may have real practical and clinical implications. Trained coders in the Dyadic Parent-Child Interaction Coding System Revised, coded 40 half-hour videotapes of 33 parent-toddler dyads interacting in the home on 29 items of dyadic behaviour. Four theorised composite variables were constructed. Videotaped data were compared to data drawn from the same interactions previously coded ‘live’ in the home. Correlations indicated significant agreement between the two modes at the item by item level (p < .001). Wilcoxon Rank tests revealed significant differences (p < .001) between the two modes. Eight items exceeded a ±30% change in median score suggesting clinically relevant differences. Although both methods achieved acceptable levels of inter-rater reliability, video coding achieved higher levels of agreement. Subtle differences exist between the two modes. Whilst neither mode proved superior it is suggested that they should not be used interchangeably.

PyObs: Open-Source Software for Computer-Assisted Behavioral Observation Coding

pyObs is a computer-assisted behavioral observation coding system used to record social interaction among children in classroom and playground settings. Its flexible architecture allows it to be useful for capturing behaviors occurring in settings that vary across age group or context. Written in Python, pyObs has a cross-platform GUI using drop down menus and check boxes along with audio and visual cues that increase coder reliability. Time-stamped GIS maps record subject location. And data are output into standard formats, such as csv. pyObs is extensible, making it simple to change the interface depending on the research objectives.

Wie lassen sich Studierende hinsichtlich ihrer (Selbst-)Reflexionsfähigkeit typisieren?

The paper addresses the increasingly important issue of professionalization of prospective teachers and, within this process, the promotion of (self-)reflection as an essential element of professionalism. Specific focus is to model the capability to (self-)reflect. (self-) reflection means both the self-reflection of the students about themselves and their actions as well as the reflection on external circumstances and structural factors. In order to make this understanding tangible, a competency structure and level model of (self-)reflection is developed with a content-analytic approach and used as a starting point for the analysis of the (self-) reflection competence of prospective teachers. The model comprises the four dimensions: Inward look backwards, outward look backwards, inward look forward and outward look forward with 4 consecutive levels each. To confirm the competency structure and level model, a reflection motive of 265 students of vocational and business education is evaluated content-analytically by means of a coding guide. This coding guide is characterized by a high degree of intra and inter coder reliability (Krippendorfs ɑ ≥ .92). By means of an LCA, three classes of (self-)reflection types could be identified among the students. In each class, the inward look backwards has the highest level and in all classes there is a clear potential for improvement with regard to the outward-looking dimensions. The developed competency structure and level model provides information on how the (self-)reflection competence can be purposefully analyzed and promoted. The three types of (self-)reflection that were identified allow teacher educators to take into account the level of (self-)reflection competency when designing courses and to adapt the lessons to learners’ requirements. Against this background, it can be said that the competency structure and level model provides teacher educators with an analytical tool, because it uses the types of (self-)reflection to explain and describe options as well as oriented knowledge for a targeted promotion of (self-)reflection competence, which is based on the existing (self-)reflection level of the students.

Applications of a finite-volume algorithm for incompressible MHD problems

We present the theory, algorithms and implementation of a parallel finite-volume algorithm for the solution of the incompressible magnetohydrodynamic (MHD) equations using unstructured grids that are applicable for a wide variety of geometries. Our method implements a mixed Adams-Bashforth/Crank-Nicolson scheme for the nonlinear terms in the MHD equations and we prove that it is stable independent of the time step. To ensure that the solenoidal condition is met for the magnetic field, we use a method whereby a pseudo-pressure is introduced into the induction equation; since we are concerned with incompressible flows, the resulting Poisson equation for the pseudo-pressure is solved alongside the equivalent Poisson problem for the velocity field. We validate our code in a variety of geometries including periodic boxes, spheres, spherical shells, spheroids and ellipsoids; for the finite geometries we implement the so-called ferromagnetic or pseudo-vacuum boundary conditions appropriate for a surrounding medium with infinite magnetic permeability. This implies that the magnetic field must be purely perpendicular to the boundary. We present a number of comparisons against previous results and against analytical solutions, which verify the code's accuracy. This documents the code's reliability as a prelude to its use in more difficult problems. We finally present a new simple drifting solution for thermal convection in a spherical shell that successfully sustains a magnetic field of simple geometry. By dint of its rapid stabilization from the given initial conditions, we deem it suitable as a benchmark against which other self-consistent dynamo codes can be tested.