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Objective : This research aims to propose a large-scale vehicle routing model for the distribution network of a food industry product and apply the model in a real-world case study. Methods : A mathematical model is formulated to minimize the total variable transportation costs.  Considering the complexity of the model, a constrained clustering algorithm is used to decompose the problem. Then, vehicles are assigned to demand clusters according to their capacity. Finally, each cluster's symmetric traveling salesman problem (TSP) is solved using a genetic algorithm. The parameters of the proposed genetic algorithm were calibrated based on its widespread application in solving symmetric TSPs. A conservative approach was adopted to ensure the solution's validity by evaluating a worst-case scenario considering the highest node demands.  Results : By applying the proposed algorithm to the case study, over 2,000 demand nodes across Tehran were grouped into 91 clusters. Then, based on the demand level of each cluster, the vehicles are assigned, consisting of 26 small and 65 large cars. Within each cluster, the assigned vehicle followed an optimized route among the nodes, designed based on the optimal tour generated by solving the cluster-specific TSP using the genetic algorithm, and then returned to the central warehouse. Conclusion : Comparing the results with the current situation, the size of the proposed transportation fleet showed a 40% reduction. Additionally, reducing fleet size and optimizing the routes improved the total distribution network costs by 25%. Given the model's computational efficiency, this improvement is considered satisfactory.

Objective: The objective of this study was to evaluate the effectiveness of an educational program based on the Marital Distress Tolerance Model on reducing marital conflicts among conflicting couples in Tehran. Methods and Materials: This research employed a quasi-experimental design with a pretest-posttest control group. The statistical population included all conflicting couples who visited psychological and counseling centers in Tehran. One center was randomly selected, and 30 couples were chosen through convenience sampling and randomly assigned to experimental and control groups (15 couples each). The experimental group received a 9-session intervention based on a structured educational package developed from the causal model of marital distress tolerance, focusing on cognitive flexibility, family health, and social problem-solving skills. Data were collected using the Barati and Sanaei Marital Conflict Questionnaire and a researcher-developed content validity instrument evaluated by experts. Descriptive statistics and multivariate analysis of covariance (MANCOVA) were used to analyze the data through SPSS software. Findings: The results of the MANCOVA indicated that the educational program had a statistically significant effect on all dimensions of marital conflict, including reduced sexual relations (F = 28.438, p < .001), increased emotional reactions (F = 18.448, p < .001), separation of financial matters (F = 29.932, p < .001), reduced cooperation (F = 22.822, p < .001), reduced relationships with spouse’s relatives (F = 18.549, p < .001), increased relationships with one’s own relatives (F = 10.030, p = .005), and increased seeking support from children (F = 65.565, p < .001). Conclusion: The study confirmed that the educational program based on the marital distress tolerance model significantly reduced marital conflicts across multiple dimensions, supporting the model’s applicability in therapeutic interventions for couples experiencing relational distress.

This research delves into the complex relationship between dynamic managerial capabilities (DMCs) and innovation performance, examining the moderating effects of activity type, export level, and firm size. Employing rigorous ANOVA methodologies, the study elucidates the nuanced and conditional impacts of managerial actions on innovation outcomes. A significant aspect of this investigation is the classification of managers based on their specific DMC components, a novel contribution to the field that enhances our understanding of how different managerial competencies shape innovation. The results indicate substantial interactions between DMCs and the outlined contextual factors. Notably, Type 1 managers, distinguished by their superior managerial human capital, expansive social networks, and propensity for intuitive decision-making, demonstrate a robust positive effect on innovation across varied activities. In contrast, Type 9 managers, who possess limited managerial human capital yet maintain extensive social networks, display performance variability contingent on operational contexts. In export-centric firms, both Type 1 and Type 5 managers emerge as key drivers of innovation, adeptly maneuvering the complexities of international markets through their strategic acumen and flexibility. Moreover, the effectiveness of DMCs is significantly modulated by firm size, with micro and small enterprises deriving optimal benefits from a multifaceted managerial skill set, whereas larger corporations exhibit a greater reliance on established systemic processes. This research lays the groundwork for subsequent inquiries into the strategic deployment of DMCs in diverse organizational scenarios and offers critical insights for enhancing innovation-led development.

Avicenna’s floating man thought experiment has been examined and criticized for over a thousand years from various philosophical perspectives. While traditional and modern criticisms exist, the latter primarily focus on the confusion between epistemology and ontology. The ontological dimensions have received significant attention, but the epistemological aspects remain underexplored. I propose a modern critique suggesting that if valid, the thought experiment may not support substance dualism. However, some modest versions could bolster modest dualism, which posits that mental properties are distinct from physical ones, without adhering to Cartesian concepts. I present seven versions of the thought experiment. The first differs from Avicenna’s original and focuses on the individuation of self and body, but is vulnerable to modern critiques due to its conflation of ontological and epistemic aspects. The remaining six versions avoid this issue and do not assert that the mind is an immaterial substance. The second version examines epistemic differences between basic self-knowledge and knowledge of the body. The third addresses self-referential and self-verifying aspects of self-knowledge. The fourth explores modal properties, while the fifth highlights the self's necessary relationship to self-knowledge. The sixth emphasizes the environmental neutrality of basic self-knowledge, and the final version utilizes the self as a critical reasoner. I also support and revise these six versions with eleven general remarks.