Introduction 
Currently, the acceleration of population growth and the increasing rate of urbanization are maintaining their advancing boundaries at both national and global levels. In this regard, there is a need for new intellectual reflections and the utilization of practical capacities from applied sciences such as urban planning and architecture, including the approach to building new towns. These new towns share extensive commonalities with fundamental concepts and categories of urban planning and urbanization, such as “metropolises,” “population growth,” “housing construction,” “quality of life,” “self-sufficiency,” and “urbanism,” and have consistently maintained their connection to these concepts within a cohesive conceptual network. The establishment and construction of new towns, in its twentieth-century sense, is one of the well-known policies in the theoretical and practical realm of urban planning, which is currently being addressed by new generations globally and can be viewed from various angles. In this context, different countries around the world have each moved towards the establishment of twenty-first-century new cities in their own ways. The emergence of newer types and generations of new towns has increased the significance of these settlement patterns due to a transformation in the perspective towards these cities, diversity in goals and approaches, and because of the focus on qualitative dimensions in this category of towns. However, a review of the research literature and the theoretical foundations available in second-generation new towns, especially in Iran, indicates that sufficient and rich guiding research and ideas have not yet been developed, resulting in a scientific gap. Therefore, new-generation towns in Iran require specific settlement models supported by special, precise, and robust theoretical foundations. This research aims to fill the aforementioned knowledge gap and to elucidate the exploratory mixed model for the establishment of new-generation new towns, with a case study of the new city of Tiss.
Materials and Methods
The approach of the present research is a mixed-methods approach among the three types of research approaches, and its nature is applied. In this context, and in line with identifying the optimal exploratory model for the establishment of the new city of Tiss and the components and elements related to it, a mixed-methods strategy has been employed, including sequential mixed-methods procedures and sequential exploratory design, utilizing qualitative and quantitative methods in succession. The operational tools of the research consist of two researcher-made questionnaires, one qualitative and one quantitative, where the qualitative section was developed first, and then the quantitative section was formed based on the outputs of the first questionnaire.
 The qualitative outputs were used to identify the components of the optimal establishment model for the city of Tiss, and the final establishment model of the city was introduced and explained through the interaction of the quantitative outputs with the qualitative section. The data collection method in the questionnaires involved the use of grounded theory’s inductive approach and hierarchical analysis methods in the qualitative and quantitative sections, respectively. For better analysis of these data, two software programs, Maxqda and Expert Choice, were utilized. In the grounded theory section, the classic Glaserian model and the stages of substantive coding, including open coding and selective coding, as well as theoretical coding, were employed. In the analysis of theoretical coding, the strategy family was used to categorize the final categories. The statistical population of the research includes twenty academic and practitioner experts, divided into two groups of ten in both qualitative and quantitative sections.
Findings
The final research model consists of three layers. The first layer has a mixed exploratory nature, combining qualitative and quantitative approaches. In this layer, there are specifically twelve “basic categories” of urban establishment and forty-seven “strategic categories” of urban establishment, which respectively determine the direction of establishment and guide the form and appearance of the city. To this end, in the first step, to operationalize the exploratory mixed research process, twelve basic categories of urban establishment were identified using codes derived from “scientific constructs” and “researcher-generated” codes in grounded theory. These categories were presented to experts for confirmation or enhancement, ultimately leading to the stabilization of the same twelve basic categories of urban establishment due to the lack of aggregation and saturation of new basic categories. The forty-seven “strategic categories” were also identified using expert-centered internal codes. Thus, through two qualitative and quantitative phases, four basic components—”urban tourist acceptance,” “urban livability,” “urban infrastructure,” and “civic-social dimensions”—received the highest scores among the twelve basic categories, and the strategic sub-criteria for these four components were identified in subsequent steps of the research. 
In addition to the first layer, the second and third layers represent the conceptual model of the establishment of the “physical body” and the conceptual model of the establishment of the “coast” of the city of Tiss, respectively. In these two layers, due to the tourism dimensions of Tiss, concepts, and categories of tourism were used alongside urban planning concepts and categories. The mechanism of these three layers operates in such a way that they function integrally, with no possibility of separating them from one another, and their implementation also requires the refinement of strategic categories in a case-specific manner. In this context, a set of “cohesive coordinates” and “sustaining coordinates” for the body of the city and the coast of the city have also been incorporated into both the second and third layers, covering the external and internal elements that shape the structure of the city, respectively. For these two models, initially, a single-core establishment model was introduced for each, and from the combination of these two “single-core models,” a more comprehensive model named the “dual-core model” emerged, which represents the most complete desirable establishment model for the city of Tiss, encompassing both the desirable establishment model of the city’s body and the desirable establishment model of the city’s coast in an integrated and unified manner.
Conclusion
The new generation of towns requires special settlement patterns due to their complexity and qualitative approaches. These patterns can have specific orientations based on the unique nature of each of these new towns. Accordingly, based on the findings of the research, the three introduced layers, along with the “single-core” and especially the “dual-core” patterns, present a comprehensive image of the desired settlement pattern for the city of Tiss. These patterns not only explain how the city of Tiss should be settled but also elaborate all the components and elements of these three layers together. In this regard, they can serve as a model for other new-generation towns, including other new tourist-friendly cities such as “Ferdows” and “Tabnak”, for discussion and evaluation.