Model Theory Research Articles

Exploring Reasons For Self-Harm Among Teenagers: A Phenomenological Study Of Selected Public Secondary School Students In Nairobi County, Kenya

Self-harm involves a person injuring themselves deliberately. This may take any form. This study aimed at deepening understanding of the phenomenon of self-harm through a qualitative research approach based on phenomenological research design. The research was conducted in Embakasi Girls High School and Our Lady of Mercy Girls High School in Nairobi County, Kenya. The objectives of the research were to know the reasons for self-harm, and the possible mitigation measures. A population of seven respondents were interviewed. The theories of dual harm model and Cognitive Behavioral Theory were used. Data was collected through semistructured interview questions developed by the researcher. This allowed for transparency and enabled extraction of subjective details on the topic. The study employed purposive; typical case and convenient sampling approaches. Descriptive data was then analyzed through thematic content analysis where the researcher identified repeated patterns guided by the research objectives. The results identified cutting, burning, scratching, and medication overdose as the types of prevalent self-harm. Loss and grief, bullying, relationship strains, distressing emotions, and academic pressures were some of the reported reasons for self-harm. Results suggested counseling and being listened to as mitigation measures. Some did not know the kind of help they needed while others stated that they did not need help. The findings are likely to help psychologists, parents, learning institutions, and society; to understand some basic psychological needs of adolescents who engage in self-harm and devise ways of helping them

A coupled fractal model for predicting the relative permeability of rocks considering both irreducible fluid saturation and stress effects

The relative permeability of rocks is an essential parameter for evaluating two-phase flow characteristics and plays an important role in engineering fields such as resource exploitation. To this end, a mathematical model for predicting relative permeability was first developed based on an equivalent capillary model and fractal theory. The proposed model considers the irreducible fluid saturation under stress and quantifies the influence of the pore structure characteristics on the relative permeability. This model was then compared with relevant experimental data and existing theoretical expressions to verify its validity. Finally, the factors affecting the two-phase seepage characteristics were discussed. The results show that the irreducible fluid saturation is intimately connected to the fractal dimensions, pore size, fluid viscosity, pressure drop gradient, and elastic modulus. Fluid properties and pore structure characteristics are the main factors affecting relative permeability. The wetting phase relative permeability is more sensitive to pore structure and irreducible fluids. Increased effective stress increases irreducible fluid saturation, reduces two-phase flow capacity, and significantly decreases the relative permeability of wetting phase fluids. Increased elastic modulus and Poisson's ratio decrease the irreducible fluid content under stress and increase the permeability.

The analysis of evolutionary strategies to facilitate the transformation of traditional buildings into prefabricated buildings

This paper establishes a two-party evolutionary game theory model comprising of the governments and prefabricated components suppliers as the players; and uses the replicator dynamic equations to analyze the evolution mechanisms each player’s strategy choices. Results from numerical simulations indicate that the evolution trajectory of the model is significantly influenced by not only the initial strategies of the players, but also by government incentives and regulatory penalties, as well as the costs and benefits resulted from each strategy choice. Also, prefabricated components suppliers exhibit greater responsiveness to variations in cost-related factors. When the subsidy and penalty respectively remain constant at 15% and 5% of the additional cost, the model exhibits both rapid and stable evolutionary trend towards the optimal evolutionarily stable strategy of full cooperation between the two players. This article proposes a suitable threshold for government incentives and penalties, besides serving as a guide for the steady and sustainable growth of the prefabricated buildings sector.

Evaluation of habitat suitability and migratory paths of an endangered raptor, Steppe Eagle (Aquila nipalensis) in Iran

Understanding habitat suitability, the environmental variables limiting the distribution of species, and migratory paths are important issues for conservation of threatened bird species. Identifying areas important for birds and their overlap with conservation areas (CAs) can guide conservation managers in establishing new CAs. The Steppe Eagle (Aquila nipalensis) is a globally endangered winter visitor raptor in Iran. We used 164 occurrence records of Steppe Eagles and data on 12 environmental variables in Iran as input to ensemble modeling and electrical circuit theory models to identify, respectively, potential wintering areas and migratory paths between those wintering areas. Our results revealed that elevation, distance to rodents, mean diurnal range, distance to villages, and distance to cities were the most influential variables for habitat suitability in Iran. Potential wintering areas identified by our models were mainly located in the north and south of Iran and migratory paths connected these areas through the central plains. CAs covered about one-fifth of potential wintering areas. Conservation of the species within potential wintering areas and the migratory paths from northern to southern Iran is necessary for the survival of this endangered species in its entire distribution. Therefore, wildlife managers should pay increased attention to non-protected parts of potential wintering areas in order to establish new CAs and protect migration paths against threats. Our results pave the way for proper planning for the conservation of threatened raptors in Iran, particularly Steppe Eagle.

Echoes of violence: experiences of Palestinian Arab students in Israeli academia during the violent events of May 2021

AbstractThis paper investigates the challenges faced by Palestinian Arab citizens of Israel (PAI) who are students in Israeli higher education institutions amidst periods of national turbulence and violence, particularly focusing on the violent events of May 2021. Using interviews with students, academics, and members of civil society organisations, the paper puts forth a constructivist grounded theory model that charts the impact of the violent events of May 2021 on PAI students. It reveals that students’ experiences of violence, in various forms, give rise to a host of emotional, social, and political processes that heighten their awareness of the structural violence of the broader Israeli-Palestinian struggle. In response, PAI students withdraw both physically and mentally from their campuses and concurrently mobilise within their communities to address unmet needs neglected by official authorities. The perceptions of PAI students regarding their institutions’ responses to political issues are marked by intense cynicism—a sentiment that is mitigated by individual supportive initiatives by faculty members. Based on the findings, the paper argues that periods of political escalation are not to be viewed as fleeting events that heighten emotions but rather as critical junctures where identities and perceptions are formed, leaving an impact that lasts long after the immediate turbulence subsides.

Solving Max-cut Problem with a mixed penalization method for Semidefinite Programming

This paper is an attempt to exploit the opportunity of Semi Definite Programming (SDP), which is an area of convex and conic optimization. Indeed, Numerous NP-hard problems can be solveby using this approach. Hence, we intend to investigate the strength of SDP to model and provide tight relaxations of combinatorial and quadratic problems in order to present a new polynomial time algorithm for solving this robust model. This algorithm was firstly use to solve the nonlinear programs, the reason for which we search to extend it to the SDP programs. Actually, this algorithm designs the combination of two penalization methods. The first one is a primal-dual interior point (PDIM) method while the second one is a primal-dual exterior point (PDEM) method. Unlike the first method, which converges globally, the second one, also called the primal dual nonlinear rescaling method, has local super linear/quadratic convergence. Therefore, it seems appropriate to use a mixed algorithm based on the interior-exterior point method (IEPM). In fact, this resolution starts from the interior method, and at a certain level of execution, it proceeds to exterior method. Hence, a convergence evaluation function is use to know the level of permutation. Through evaluation, it has been approve that our approach is use to solve some instances of max-cut problem. This problem is a central graph theory model that occurs in many real problems and it is one of many NP-hard problems, which has attracted many researchers over the years. Then, we have used a semi definite programming solver SDPA (Semi Definite Programming Algorithm) that is modify to include the exterior point method subroutine. From the computational performance, we conclude that as the problem size increases, interior-exterior point algorithm gets relatively faster. The numerical results obtained are promising.

A brigde toward mathematics theory in living systems: the thermostatted kinetic theory method for crowd dynamics: Comment on the review paper “A decade of thermostatted kinetic theory models for complex active matter living systems” by Carlo Bianca

A brigde toward mathematics theory in living systems: the thermostatted kinetic theory method for crowd dynamics: Comment on the review paper “A decade of thermostatted kinetic theory models for complex active matter living systems” by Carlo Bianca

Social Innovation Management to Support Integrated Care: Insights from an Italian Revelatory Case Study

This research deals with Social Innovation (SI) and integrated and connected care in the hospital care, presenting a successful experience of telemedicine's implementation within the Italian context. Nowadays integrated care and connected care are relevant concepts for delivering people-centered healthcare; though their operationalization is challenging and requires accounting for systems' complexity. In this regard, SI may be a catalyst, since it consists in a kind of innovation motivated by social needs. Extant research on SI in healthcare is scant and fragmentary, overlooking operational features and enabling conditions. Considering these gaps, the paper investigates the potential contribution of SI management to integrated and connected care. For the purpose, it offers a revelatory case study, concerning the pediatric research hospital Gaslini (Genoa, Italy), which is, to our knowledge, the first Italian public hospital to have hired a SI manager. By referring to a telemedicine pilot project, the study analyzes main features of the SI management process and its approach to promote integrated and connected care. Research data are analyzed by combining Gioia methodology and systems thinking. The resulting grounded theory model is causal loops-shaped and highlights virtuous mechanisms of SI unveiling generative voids and existing skills.

Modeling Skipped Items in Cognitive Diagnostic Assessments

In cognitive diagnosis assessments, examinees frequently skip some items due to various reasons, such as time constraints, lack of confidence, or the perception of item difficulty. These skipped items are usually due to lacking specific cognitive attributes or knowledge structures. However, many research studies conventionally rely on complete-case analysis, potentially compromising the validity of results by ignoring skipped items. This omission can lead to invalid inferences about the attributes profiles of examinees and introduce bias into item parameters. This study aims to develop statistical models for effectively handling missing data resulting from skipped items. Specifically, we employ an item response theory model for missing indicators and utilize the deterministic inputs, noisy “and” gate (DINA) model to describe cognitive item responses. Furthermore, we introduce a higher-order structure to describe the correlation between the higher-order ability parameters and skipping propensity parameters and the correlation of the item parameters. The proposed new model fills the gaps in missing data handling, providing a more precise evaluation for the examinees who skip items and yielding more accurate research results. This enhances our understanding of cognitive processes and strengthens support for educational policies, aligning them better with student needs and optimizing decision-making.

Evaluating the carbon emission reduction in construction and demolition waste management in China

Construction and demolition waste reduction (C&DWR) is an important measure to protect the environment and promote sustainable development in the construction sector. The present policy in China remains a lack of emphasis on carbon tax and penalty for reducing construction waste. This paper proposes a construction and demolition waste (C&DW) management model to identify the waste reduction effects of various policies in China. It simulates the effects of single policies and combined policies on waste reduction and carbon emission by using the approach of integrating system dynamics and grey model theory. The results reveal that: (1) Penalties can effectively reduce the amount of illegal dump waste and carbon emissions from illegal dump waste, with an appropriate penalty value (in Chinese CNY) suggested as ∈160,320. (2) Subsidies can vastly increase the amount of waste recycled and a carbon tax can reduce carbon emissions; the recommended values are suggested as subsidies ∈30,45 and carbon tax ∈40,70. (3) Compared to other policies, the combined policy of penalty–waste disposal charging fee–subsidy–carbon tax (160, 60, 45, 70) achieves the greatest environmental benefits in terms of reducing waste and carbon emission. (4) Governments should improve waste minimization incentive policies and gradually introduce trials for a carbon tax policy, encourage the use of digital governance combined with blockchain technology to regulate C&DW. These findings provide valuable insights for policymakers to develop effective waste reduction strategies and promote sustainability through the implementation of C&DWR theories.

Determinants of E-Learning Acceptance in Indonesia Post-COVID-19 and Its Impact on Students’ Technopreneurship

Objective: This research aims to address the gaps in country-specific e-learning studies by examining the key factors influencing e-learning adoption in Indonesia. Grounded in a comprehensive literature review on flow theory, service quality, and technology acceptance models, the study develops a research model that includes four independent variables (instructor characteristics, teaching materials, content design, and enjoyment), two belief variables (perceived usefulness and perceived ease of use), and one dependent variable (intention to use e-learning). Method: Data were collected from 404 respondents, comprising students and lecturers at state Islamic universities in Indonesia, using convenience sampling. The study employed SEM-PLS for data analysis, validating the research instrument's reliability and validity. Results: The results offer insights into the managerial implications and suggest directions for future research in e-learning adoption. Its results confirm six hypotheses. Novelty: This study fills a gap in e-learning adoption research by focusing on Indonesia and integrating flow theory, service quality, and technology acceptance models. It highlights the roles of perceived playfulness, ease of use, and instructional content design in influencing e-learning adoption while challenging the expected impact of instructor characteristics. This research provides fresh insights into technology-driven learning in the context of developing countries.

Mediation of customer satisfaction: E-service quality, brand trust, and reuse intention

The purpose of this study is to explain the role of customer satisfaction in mediating e-service quality and brand trust on reuse intention in the Traveloka application. The theories used are the Techlonogy Acceptance Model (TAM) and Expectancy Disconfirmation Theory (EDT). This research is a type of quantitative research that is associative in nature. The population in this study are all Traveloka application users who have transacted at least three (3) times in one year. The sampling technique used purposive sampling with a total sample member of 205 respondents. Respondent data collection was carried out by distributing questionnaires. The data analysis technique in this study used PLS-based SEM. The results showed that all variables had a positive and significant effect. Customer satisfaction acts as a partial mediation in mediating the effect of e-service quality and brand trust on reuse intention on the Traveloka application. The results of this study can provide an empirical contribution about the relationship between the variables of e-service quality, brand trust, customer satisfaction, and reuse intention for the development of the Technology Acceptance Model (TAM) and Expectancy Disconfirmation Theory (EDT). Traveloka management can implement a marketing strategy that emphasizes service quality and information accuracy to increase customer intention to reuse the Traveloka application.

A COGNITIVE STUDY OF DRINK EXPRESSIONS IN ENGLISH PROVERBS

Conceptual Metaphor Theory represents the output of a cognitive process by which readers can understand one domain in terms of another. This study aims to investigate the use of drink proverbs in English from a cognitive point of view and investigate the role of metaphor in communication as an unconscious process in everyday life. Also, it aims to identify metaphor as a systematic process that does not occur randomly. It is considered as a problematic task for learners to understand, interpret, and render the exact conceptual meaning of English proverbs. The procedures of this study are as follows: Presenting a theoretical framework of cognitive linguistics and adopting the model of the conceptual metaphor theory which is Lakoff and Johnson's “Metaphor We Live by” (2003) to analyze proverbs of drink in English. Another two models are used to support the first one which are Newman's (1997) “Eating and Drinking as a Source of Metaphor in English” and Quirk et al (1985) “A Comprehensives Grammar of the English Language”. The study hypothesizes that the source and target domains in conceptual metaphors have a crucial role in understanding the meaning of drink proverbs in English. Concerning the levels of analysis, the present study deals with the semantic and grammatical levels. The data are collected from dictionaries that are associated with drink proverbs. Six samples are chosen for the analysis. In each sample, more than five items have been analyzed metaphorically and grammatically. The present study concluded that conceptual metaphors do not occur randomly and they are unconscious processes through conversations.

Large Deflection of a Single-Phase-Lag Non-Simple Hygrothermoelastic Elliptic Plate Under Heat-Moisture Load

A novel mathematical model in hygrothermoelastic theory has developed to describe heat and moisture distribution in a nonsimple medium. The model incorporates non-Fourier and non-Fick laws using a single phase-lag model to establish a relation between hygrothermoelasticity and unstable conduction processes. The model is applied to an ellipse-shaped composite material subjected to humid-heat loading. The Laplace and Mathieu integral transform was employed to obtain an exact solution of linearly coupled partial differential equations in an elliptical coordinate system. The Gaver–Stehfest algorithm is utilized for the inversion of Laplace functions. Berger’s approximation equation was employed to simplify the calculation of significant deformations for elliptic plates. The model also provides quantitative results for the composition of T300/5208, which consists of epoxy resin reinforced with graphite fibers. The hygrothermal behaviors due to the single-phase-lag time, geometry dimensions, material type, and the two temperatures are explored. The results reveal that nonclassical theories with single-phase-lag time and two-temperature have significant influences on the hygrothermoelastic behaviors in elliptic-shaped objects. The investigation can be effectually led using micro- and nano-elliptic shape resonators in future research.

Impacts of cultural practices on consumers’ buying behavior in sales promotional activities in the settings of COVID-19

PurposeThis study aims to explore the impact of cultural practices on consumers’ buying behavior in sales promotional activities toward the fashion clothing brands based on the Theory of Black-Box Model under the conditions of COVID-19 at Pakistan.Design/methodology/approachThe study has collected data through questionnaire-based survey from 600 consumers of fashion clothing brands using convenience sampling technique in Pakistan and analyzed through PLS-SEM to find results.FindingsThe results confirmed that cultural practices and sales promotional activities have positive significant relationship with the consumers’ buying behavior during the celebration of events, also under the conditions of COVID-19. The study also found that ethnocentrism and xenocentrism are positively associated with cultural practices while social factors, physical factors, product innovation and marketing innovation with sales promotional activities.Practical implicationsThe outcomes provide interesting insights about consumers’ assessment toward the sale’s promotional activities and cultural practices of fashion clothing brands during the celebration of events and guide the marketing practitioners to develop the customers edifying and environment-oriented business strategies to boost up the buying behavior in crisis situations.Originality/valueAlthough prior research has widely investigated the cultural practices, sales promotion and consumers’ buying behavior in various settings, but to the best of the authors’ knowledge, this is the first study in these domains.

Deep learning in standard least-squares theory of linear models: Perspective, development and vision

Inspired by the attractive features of least-squares theory in many practical applications, this contribution introduces least-squares-based deep learning (LSBDL). Least-squares theory connects explanatory variables to predicted variables, called observations, through a linear(ized) model in which the unknown parameters of this relation are estimated using the principle of least-squares. Conversely, deep learning (DL) methods establish nonlinear relationships for applications where predicted variables are unknown (nonlinear) functions of explanatory variables. This contribution presents the DL formulation based on least-squares theory in linear models. As a data-driven method, a network is trained to construct an appropriate design matrix of which its entries are estimated using two descent optimization methods: steepest descent and Gauss–Newton. In conjunction with interpretable and explainable artificial intelligence, LSBDL leverages the well-established least-squares theory for DL applications through the following three-fold objectives: (i) Quality control measures such as covariance matrix of predicted outcome can directly be determined. (ii) Available least-squares reliability theory and hypothesis testing can be established to identify mis-specification and outlying observations. (iii) Observations’ covariance matrix can be exploited to train a network with inconsistent, heterogeneous and statistically correlated data. Three examples are presented to demonstrate the theory. The first example uses LSBDL to train coordinate basis functions for a surface fitting problem. The second example applies LSBDL to time series forecasting. The third example showcases a real-world application of LSBDL to downscale groundwater storage anomaly data. LSBDL offers opportunities in many fields of geoscience, aviation, time series analysis, data assimilation and data fusion of multiple sensors.

Behavior intention in coping cloud adaptation

This study investigates the indirect impact of perceived technology complexity on the adoption of cloud platforms by data scientists in Brazil. Specifically, it examines the mediating role of perceived work-related opportunities and behavioral intentions, as well as the use of exploration-to-innovate coping strategies. The research employs an online questionnaire survey and uses Confirmatory Factor Analysis, SEM, and OLS to analyze the data. The findings suggest that a serial mediation effect focused on behavioral aspects can better explain the adoption of cloud computing technology. The study identifies the need for further investigation into the potential moderating effects of voluntariness and self-efficacy on the relationship between perceived technology complexity and cloud platform adaptation. Moreover, incorporating other exogenous constructs such as new adaptation strategies, job outcomes, and job satisfaction may provide a more comprehensive understanding of the factors influencing technology adoption in the context of data science. The study highlights that reducing technology complexity can lead to increased adoption, better user experience, better retention rates, more innovation possibilities, and better competition position. However, additional training and support requirements for data scientists can increase the cost and time required for onboarding and maintenance. A cloud platform that is easy to use can enable remote work and collaboration, opening up opportunities for job growth and flexible work arrangements. This can be particularly beneficial for Brazilian professionals who have strong innovation skills but limited training and support. By transcending geographic barriers and infrastructure limitations, a user-friendly cloud platform can help bridge the digital divide. On the other hand, a complex cloud platform can widen the digital divide, particularly in developing countries, exacerbating existing inequalities. The research contributes to theory building by providing a serial mediation framework that better explains technology adaptation phenomena by combining coping theory and technology acceptance model.

한국 부부·가족상담 전문가들의 공통요인(common factors) 경험에 관한 합의적 질적 연구

Objectives: The purpose of this study is to explore the experiences of Korean couple and family counseling professionals regarding common factors, and to derive the common factors that they recognize. Methods: Consensual Qualitative Research (CQR) was applied to collect data through in-depth interviews with 10 couple and family counseling experts. Results: Eight areas and 31 sub-areas were derived. First, Korean couples and family counseling professionals' experiences on common factors were found through “the need for theory and counseling models”, “the need for an integrated approach”, and “recognition of common factors”. Second, the general common factors of couple and family counseling were “therapist factors”, “client factors”, “cooperative relationship factors”, and “therapeutic intervention factors”. Third, the specific common factors of couple and family counseling were “dealing with subsystems”, “changing perspectives on problems”, “breaking away from dysfunctional patterns”, “expanding into systemic change”, and “restructuring relationship experiences”. Conclusions: By deriving common factors in domestic couple and family counseling, we established an integrated understanding of the principles of therapeutic change and the basis for effective intervention.

Disclosure dilemma: Revealing biological paternity to family and others after unexpected direct‐to‐consumer genetic results

AbstractObjectiveThis study explores the experiences of direct‐to‐consumer (DTC) genetic test results of recipients who learn of unexpected biological paternity, not parent expected (NPE). We characterize the process of disclosing NPE discoveries, as well as the benefits and the repercussions of such disclosures on individuals, families, and others.BackgroundThe popularity of DTC genetic testing is increasing. Consequently, many discover unexpected information about their ancestry, heritage, and paternity.MethodsThis qualitative study used an inductive thematic analysis of in‐depth interviews with adults (n = 27; aged 40–70) who received DTC genetic test results revealing unexpected biological paternity.ResultsThe NPE disclosure dilemma encompasses uncertainty about narrating their discovery; gauging the dispositions of others; wondering what repercussions may arise; and managing feelings about stigma, betrayal, and anger. Culture, history, and family dynamics are vital in navigating disclosures. A desire to understand their origins, connect with new genetic families, and validate their sense of self is essential. Biological connections of kinship remain important arbiters of relatedness for many individuals.ConclusionDisclosure of NPE discoveries differs from other stigmatized identities because the secret belongs to someone else; thus, self‐disclosure affects the entire family system.ImplicationsDrawing on family systems theory and disclosure processes model, our findings provide insights into the intricate dynamics inherent in NPE disclosure.

Why Are Young People Willing to Pay for Health? Chained Mediation Effect of Negative Emotions and Information Seeking on Health Risk Perception and Health Consumption Behavior.

The perception of health risks can influence people's health behaviors. However, in the context of modern consumer society, few people delve into in-depth discussions on health consumption as a form of health protection behavior. Inspired by the Health Belief Model and Protection Motivation Theory, this study interprets health consumption behavior as a new form of health protection behavior. A survey was conducted on a sample of Chinese youth (N = 885) to explore the mechanisms of action between health risk perception and health consumption behavior using structural equation modeling. The study found that: (1) health risk perception has a significant positive impact on the health consumption behavior of young people; (2) negative emotions and information seeking play mediating roles respectively in the mechanism of the impact of health risk perception on health consumption behavior; and (3) in addition to their individual mediating roles, negative emotions and information seeking behavior collectively play a chained mediation role in this process. Implications of these results, both theoretical and practical, are further discussed.