Aim: Knowing the processes of Transition from Start-up to Scale-up and removing the obstacles in front of it will determine the success or failure of the Start-up. Therefore, the current research was carried out with the aim of conceptualizing the interpretive structural of Transition barriers from Start-ups to Scale-ups. Method: This study is practical in terms of its objective and, given its nature, falls into the category of mixed (qualitative-quantitative) research, based on sequential-exploratory design, and data collection through descriptive and field-documentary research. The study population includes all key informants, such as entrepreneurship faculty members with relevant resumes and backgrounds, start-up owners in the transitional and existing scale-up stages, mentors, experts, and planners of relevant organizations in the start-up ecosystem of the country. In this study, three methods of inductive content analysis, Interpretive Structural Modeling, and degree of penetration and dependence analysis were used. Results: The results led to the identification of 12 obstacles for the Transition from Start-ups to Scale-ups, which were classified into 7 levels after analysis. Also, their level of influence and degree of dependence were determined in a range of independent, linked, and dependent influence. Conclusion: Barriers to transition from startups to scale-ups in order of levels, including weaknesses in environmental analysis and continuous scanning, weakness in determining appropriate goals and strategies, weakness in reviewing and developing marketing plans, team problems and weaknesses in founder leadership and management, weakness in enhancing the value proposition, weakness in establishing and shaping the structure, weakness in normative and cultural capital within the team, weakness in creating appropriate financial capabilities and reducing costs, weakness in team learning processes and empowerment, weakness in appropriate infrastructure, processes and technologies, weakness in the preparedness of individuals' mental blocks for change, and weakness in selecting the appropriate time for scaling up. The current research has identified and analyzed a set of barriers to the Transition from Start-ups to Scale-ups, which can act as a guide with a step-by-step approach to increase the percentage of successful Transition. Also, the findings of this study can provide appropriate achievements and solutions for policymakers, planners, managers, and stakeholders in the Iranian start-up ecosystem.

In this paper, we introduce the concept of stabilizers of a set in UP-algebras and introduce a new class of UP-algebras. Then we introduce and study their properties and the relationships between the left and right stabilizers of a set in UP-algebras and provide equivalent conditions for easier and faster study of new UP-algebras. We also show that, by adding a condition, the left stabilizer of a set is a UP-filter, while the right stabilizer of a set is not. In the following, we define the concepts of coatom and strong coatom on UP-algebras and examine its properties. In addition, we provide equivalent conditions for easier study of coatoms in UP-algebras. We show that for a UP-algebra A, Coatom (A)=A-{0} if and only if each subset of A contains 0, is a UP-filter of A. We also examine the relationship between coatoms and stabilizers. Finally, we introduce the generalized co-annihilator set G relative to F and study its properties.

This research paper is devoted to the application of a unit work method for the scale up of rubber mixing process in banbury type internal mixers. Mooney viscosity and carbon black dispersion factor were selected as the parameters for the determination of the state of mixing. Based on a specific compound formulation, the above mentioned parameters were measured in three mixers with different chamber sizes (60, 300 and 1500 mL). It is shown that by this method the operating points of a bigger size mixer can be accurately obtained from the experimental data obtained 011a small size mixer.