ABSTRACT Using a high safety factor in construction without precise calculations imposes high costs on the execution project. Using a low safety factor exposes the project to a high risk of failure. Therefore, determining the impact of uncertain parameters greatly aids in designing with the least possible risk. The contribution of each parameter to uncertainty can be identified through sensitivity analysis. This paper considers the impact of the uncertainty of three parameters—elastic modulus, pipe thickness, and pipe diameter—on the buckling of a marine pipeline, as these three parameters significantly influence the geometry of the pipeline. Two analyses, First ORDER SECOND Moment (FORM) and SECOND ORDER Reliability ORDER (SORM), are employed for the sensitivity analysis of the pipeline parameters. The First ORDER SECOND Moment analysis provides four importance vectors, while the SECOND ORDER Reliability ORDER analysis yields only one importance index. The results indicate that the pipe diameter has a greater impact compared to the other two parameters. The smallest difference is observed between the elastic modulus and pipe thickness, suggesting that these two parameters have a similar level of sensitivity. The reliability index values in FORM and FOSM are distinct yet close to each other, with FOSM yielding a lower value.   INTRODUCTION Submarine pipelines are subjected to various forces of different natures during installation and operation, such as hoop stress, axial force, and so on. The high temperature and pressure gradient between the well and the terminal (platform or refinery) in gas transmission lines generates significant axial force in the pipeline. If the mentioned forces exceed a certain threshold, despite the friction of the seabed and the weight of the submerged pipeline, they can cause large deformations in the pipeline or, in other words, lead to pipeline buckling. The DNV-F-110 standard (DET NORSKE VERITAS) classifies this type of buckling as global buckling, which can be categorized into horizontal and vertical buckling based on the deformation mode (Shabani et al., 2017). Global buckling is a common and likely phenomenon that can occur during the operation of a pipeline. This phenomenon can lead to defects such as failure, bending, and so on in the pipeline (Karampour and Albermani, 2014). As accessible oil fields are depleted, the need for drilling at greater depths has increased, resulting in higher temperatures and pressures due to the transportation of hydrocarbon products. Consequently, the likelihood of global buckling occurring in deep waters has increased. Due to the lower critical temperature for lateral buckling compared to the critical temperature for vertical buckling, non-buried pipelines often face lateral buckling (Karampour et al., 2013). The presence of an initial vertical defect in a non-buried submarine pipeline makes the occurrence of vertical buckling possible. MATERIALS AND METHODS The marine pipeline studied in this research has a diameter of 0.816 meters, a thickness of 0.0242 meters, and a length of 40 meters. The Poisson's ratio of the pipeline is considered to be 0.3, and the thermal expansion coefficient is taken as 1.5 × 10^-6. The residual stress from the installation of the pipeline is not considered in this study due to its insignificance compared to other forces affecting the axial force. Horizontal compressive forces are considered with a high conservative coefficient. RESULTS Three parameters E, t, and D are geometric parameters of the underwater pipeline subjected to buckling. Among the three parameters mentioned, parameters of pipeline thickness and diameter are resistance variables, and elasticity modulus is the load resistance variable. The results show that the pipeline diameter is the most important among the mentioned parameters and the modulus of elasticity is the least important. In the analysis of FORM and FOSM, there are reliability indicators for both of them, which are the basic part of reliability evaluation by the two mentioned analyses. The reliability index values in FORM and FOSM are distinct but close values, which are lower in FOSM. According to Figure (2), the pipeline diameter is the most important variable of the defined limit state function. As it is clear, the smallest difference is between E and t, in other words, these two parameters are close to each other in terms of sensitivity, with the difference that one is a load variable and the other is a resistance variable. Also, this point can be concluded that the values elated to the importance index κ have a big difference with other importance indices and the rest of the importance indices have close values. DISCUSSION AND CONCLUSION Among the three mentioned parameters, the thickness and diameter of the pipeline are variables affecting resistance, while the modulus of elasticity is a variable affecting load resistance. The diameter of the pipeline holds the greatest importance among the mentioned parameters, while the modulus of elasticity is of lesser significance. The reliability index values in FORM and FOSM are distinct yet close to each other, with FOSM yielding a lower value. The approximate equality of the reliability index in the two analyses can be expressed by the difference in the importance vectors in the two analyses, and as the importance of the variables decreases, the difference becomes more pronounced. The values related to the importance index Kappa show a significant difference compared to other importance indices, while the remaining importance indices have values that are close to each other.

For the first time in the history of logic, Afzal al-Din al-Khunaji has found tautologies and contradictories among the verity and actuality propositions. These have been formalized and investigated in First-ORDER Logic and it has been shown that their perpetual truth requires the assumption of ‘the presupposed existence of non-existence.’ In this paper, I investigate the tautologies in SECOND-ORDER Logic and show that there is no need to the aforementioned assumption, and they can be proved as theorems without any assumption in SECOND-ORDER Logic. But, the analysis of these tautologies in SECOND-ORDER Logic has its shortcomings; for example, the formalization of actuality I-propositions in many cases is contradictory. This shows that the analysis of the tautologies, whether in First- or SECOND-ORDER Logic, has shortcomings, which need to be removed.

The aim of this paper is to analyze the undamped SECOND ORDER descriptor systems to show the possibility of transform an undamped SECOND ORDER descriptor system to a pure first ORDER descriptor system, on different ways, while stating some of its benefits. Meanwhile we will introduce pure first ORDER systems and undamped SECOND ORDER systems and indicate that under some assumptions every undamped SECOND ORDER descriptor system can be changed to a pure first ORDER one.

The perturbation method is an approximation scheme with a solvable leading ORDER. The standard way is to choose a non-interacting sector for the leading ORDER. The adaptive perturbation method improves the solvable part by using all diagonal elements for a Fock state. We consider the harmonic oscillator with the interacting term, λ1x4/6 + λ2x6/120, where λ1 and λ2 are coupling constants, and x is the position operator. The spectrum shows a quantitative result from the SECOND-ORDER, less than 1 percent error, compared to a numerical solution when turning off the λ2. When we turn on the λ2, more deviation occurs, but the error is still less than 2 percent. We show a quantitative result beyond a weak-coupling region. Our study should provide interest in the holographic principle and strongly coupled boundary theory.

The clustering of cryptocurrencies as an emerging field in investment management is the main topic of this research. Applying the information-based distance matrices, we clustered the 30 most valuable cryptocurrencies. Then, we identified the most influential clustering by the concept of Minimum Spanning Tree (MST) and the centrality measures of graph theory. A SECOND-ORDER clustering, which is defined as the clustering of hierarchical clusterings, was applied to cluster 56 dendrograms. Using the most influential clustering, we identified the main clusters of cryptocurrencies and sub-clusters. The results showed that the clustering composition of cryptocurrencies changed at the period I (before COVID-19) and II (pandemic time).

Two - fold logicians of the 7th century, with reference to the difference in the syntax of generic and indefinite propositions, set out to treat it as one kind of predicative proposition and to change the t:.iyartite division into the quadripartite one. They started criticising the hvo outlooks of generic indefinite and individual propositions. There is Cl difference between generic propositions and indefinite propositions. Since the former is not reducible to the contirmation of the subject and predicate, its predicate is not included in its subject, and it,; real subject is not identical with the mentioned subject. There is no syntactical difference between the generic and individual propositions on the above - mintioned issues. Their differences pertain to the predicate. With regard to generic propositions, as distinguished from individual ones, the logicians of the 7th century realized the logical importance of SECOND ORDER concepts. The present article is an attempt to study the contribution of two - fold logicians of the 7th century to the development of logic.

In this paper, firstly, it is shown that the standard account of the concept ‘practice’ in the Wittgenstein’s philosophy is a therapeutic one. According to this account, the normative standard of the rightness and wrongness of the use of words cannot be put into words. This account can be seen as the negative aspect of the whole idea of normativity. SECONDly, I argue that therapy alone is not adequate. In ORDER to give a plausible account of the whole idea of normativity, the positive aspect of the concept ‘practice’ has to be presented. Thirdly, I suggest that distinguishing between the first ORDER and the SECOND ORDER account of the concept ‘practice’ might be a way of explaining the positive aspect. According to the first ORDER account, the constituents of the concept ‘practice’ have to be given. The SECOND ORDER account sketches out the idea that practice goes all the way down. Our confrontation with things in the world is based upon doing rather than theorising at the very basic level. Overt activities ultimately depend on mental activities.

Classification, boundedness, and existence of solutions of a SECOND ORDER nonlinear difference equation are investigated. First, it is proved that all solutions are eventually monotone. Then, the necessary and sufficient conditions for the boundedness of all solutions are established. Finally, the existence of different types of monotonic solutions are presented. The obtained results have extended and improved some existing ones.