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With the irresistible growth in digitization, data backup policies become essential more than ever for organizations seeking to improve reliability and availability of organizations' information systems. However, since backup operations do not come free, there is a need for a data-informed policy to decide how often and which type of backups should be taken. In this paper, the authors present a comprehensive mathematical framework to explore the design space for backup policies and to optimize backup type and interval in a given system. In the authors' framework, three separate cost factors related to the backup process are identified: backup cost, recovery cost and data loss cost. The objective function has a multi-criteria structure leading to a backup policy minimizing a weighed function of these factors. To formalize the cost and objective functions, the authors get help from renewal theory in reliability modeling. The authors' optimization framework also formulates mixed policies involving both full and incremental backups. Through numerical examples, the authors show how the authors' optimization framework could facilitate cost-saving backup policies.

The methodology starts with designing different backup policies based on system parameters. Each constructed policy is optimized in terms of backup period using renewal theory. After selecting the best back-up policy, the results are demonstrated through numerical studies.

Data backup polices that are tailored to system parameters can result in significant gains for IT (Information Technology) systems. Collecting the necessary parameters to design intelligent backup policies can also help managers understand managers' systems better. Designed policies not only provides the frequency of back up operations, but also the type of backups.

The original contribution of this study is the explicit construction and determination of the best backup policies for IT systems that are prone to failure. By applying renewal theory in reliability, the authors present a mathematical framework for the joint optimization of backup cost factors, i.e. backup cost, recovery time cost and data loss cost.

This study explores the characteristics of a particular vernacular architecture, which is known as terraced housing. Terraced housing can be found in many different mountainous parts of the world such as the mountainous regions of Bahrain, Afghanistan, Pakistan, Greece, Italy and Japan, which have different environmental and cultural characteristics, and which were built in response to human needs according to the particular topographical conditions. Amongst the examples mentioned, Iranian terraced housing remains distinctive with its local richness and variation, constructed and designed according to the topography of the region. Accordingly the general overview of Iranian vernacular architecture and form is examined by focusing on the environmental factors of two specific Iranian villages.

The identification of these villages is evaluated according to the topography, climate, urban pattern and spatial organization of Iranian terraced settlements. As a consequence, the analysis of case studies and data processing will enable decision makers, planners, architects and designers to become more aware of the existing architectural building tradition. The contemporary housing design problems can be solved by employing an appropriate method of design and building construction with reference to the present vernacular housing stock.

The study aims to identify the issues that restrict students to show their real performance in the design due to lacking of self-advocacy skills and suggesting a new concept to overcome these difficulties.

The current literature was surveyed to form a comprehensive understanding of the issue. A case study has been taken for three years and two groups of students were taken. Results achieved and discussed.

The result of the study showed that those students who undergo an environment equipped with knowledge about self-advocacy can perform better and the success level is relatively higher amongst these students.

This study contributes to the current literature an original knowledge that has not been previously written about (empowering self-advocacy amongst students of interior architecture). The profession of interior architecture is a relatively new profession and faces challenges in fixing its feet on the ground that is why the subject can add a real value to it to alleviate the challenge.

Rapid changes due to the globalization process, cause in disappearance of traditional values and identity in the new architectural designs, particularly in the historical settlements. Presence of courtyard in the houses of Middle Eastern and Mediterranean countries dates back to nearly six thousand years ago. Privacy is one of the fundamental notions in the spatial organization of the traditional houses in this region and courtyard is the main component that assists achieving privacy in such houses. Kashan as one of the ancient cities of Iran possessing a considerable number of distinctive traditional courtyard houses, is crucial to be interrogated in terms of its traditional architecture to maintain its values and to sustain identity of the city. Space syntax as an effective method to clarify the spatial pattern of buildings and the degree of privacy in the interior spaces is applied in this study to identify privacy concerns on the formation of courtyards in the spatial organization of the traditional houses of Kashan. This paper may contribute in providing an approach for distribution of spaces in the house according to their level of privacy and its relationship in the process of current house layout design

The purpose of this paper is to analyze the results of the Jacobian matrix linearization of the satellite attitude dynamics with modified Rodriguez parameters (MRP) as attitude representation.

The satellite dynamics is linearized using Jacobian differentiation around origin and reference values of the MRP. The controller is designed through linear quadratic regulation approach.

It is found that, for both cases the overall system converges but there exists a tracking error. The error can be reduced by increasing the controller coefficients in both cases however cannot be eliminated. In the case of linearization around zero, the torque requirements are quite higher than the case of linearization around the reference attitude trajectory.

The attempt of Jacobian linearization of a satellite dynamics with the MRP as the attitude representation constitutes the value of this paper. In addition, the results obtained in the derivations may be used in future research.

The purpose of this paper is to design and simulate a linearized attitude stabilizer based on linear quadratic regulator theory (LQR) using the multiplicative definition of the attitude.

The attitude is modeled by the modified Rodriguez parameters that provide a minimal representation of attitude and always invertible kinematics. The nonlinear model of the satellite attitude dynamics is linearized around the origin and an LQR is proposed for the linearized design. They are also simulated using the original nonlinear satellite dynamics in order to verify that the controller is operating properly. Simulations include randomly selected initial conditions to justify the stability against various initial conditions.

Theoretically, the resultant controllers are locally stable around the origin. However, the simulation results show that the attitude is well regulated in the presence of both inertia uncertainties and random initial conditions.

The originality of this work is due to its demonstration that complicated attitude regulators are not the solution for proper satellite or spacecraft attitude stabilization.

The conditions that are constantly changing and transforming by digital technologies in today's world have forced businesses to think strategically and to comply with the rules and processes of strategic management. Technologies, such as the internet of things, cloud computing, artificial intelligence, and big data, especially in the Industry 4.0 ecosystem, cause some conflicts or constructive and destructive effects on the management approaches and management strategies of businesses. Businesses need to understand these technologies and their effects to maintain their existence and manage their resources and capabilities effectively and strategically. In this chapter, it is aimed to examine the conflicts with destructive and constructive effects of digital technologies on the strategic management of enterprises. For this purpose, the literature was searched qualitatively, and a conceptual study was carried out. At the beginning of the chapter, strategic management literature was researched, and strategic management approaches and views were examined. In the next part, digital technologies in the Industry 4.0 ecosystem are explained. In the last part, digital technologies and their impacts in terms of strategic management approaches (position approach, resource-based approach, and complementing views of resources-based approach) have been examined.

After the collapse of the USSR, Eurasian integration projects, proposed by Russia, Kazakhstan and Turkey, began to develop in the post-Soviet space. Hence, there is growing interest in Eurasianism as an ideology. In this context, the study of the use of the Eurasianism's ideas in practice becomes relevant. The argument of this article is that Russia, Turkey, and Kazakstan have their own interpretations of Eurasianism's ideas to develop the ideological basis of their own integration projects. The purpose of the article is to answer the question: How is the Eurasianism used in integration projects of Russia, Turkey and Kazakstan?

The concept of Eurasianism has been viewed in terms of constructivism. On the basis of the principles of social constructivism, and in particular the works of constructivist ideologue Alexander Wendt, a comparative analysis was made. The ideas of Eurasianism in the integration processes of Russia, Kazakhstan and Turkey has been carried out based on the criteria such as the role of common ideas, identity, consciousness, memory and culture. The examples of mentioned countries were compared, to consider the development of the ideas of Eurasianism in practice.

The ideas of Eurasianism have a significant impact on the integration processes of the post-Soviet space. Eurasianism advocates for important factors such as respect for cultural and civilizational differences between different nations, their equality in the overall union and common development opportunities. Such factors are undoubtedly important for the success of integration projects. The reflection of many individual thoughts of classical Eurasians and Neo-Eurasians can be seen in the statements of various ministers and leaders of Russia, Kazakhstan and Turkey. The initiatives of these countries in creating integration projects also show the influence of the Eurasian concept.

In the 1990s, the study of Eurasianism gained new significance in academic circles. Articles and periodicals devoted to this concept were published. However, all parallels between variations in concepts of Eurasianism have been conducted on a theoretical level. The importance of this article lies in the fact that conceptual differences are compared in practice. Researchers had not previously considered the study of the relevance and productivity of Eurasianism in practice by comparing examples and experiences from different countries. The novelty of this article lies in its attempt to solve this problem.