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This paper is an optimal approach to the Inventory Model. Here, we estimate efficient inventory control for the supply chain process to balance customer demand, minimize costs, and promote sustainable practices. It is imperative to integrate a non-linear, time-dependent quadratic demand function and a judiciously designed delayed payment policy to formulate an efficient inventory model for a diminishing commodity. We aim to maximize inventory choices while considering the effects of variations in demand, deteriorating products, and the flexibility of delayed payment plans. And also, the study begins by formulating a mathematical model that captures the non-linear relationship between time-dependent quadratic demand and inventory management. The model considers the effect of product deterioration over time and introduces a delay payment policy to accommodate customers' financial preferences. The objective is to optimize the total inventory cost concerning different decision variables associated with delayed payments. [ABSTRACT FROM AUTHOR]

Fractal provides many methods for characterizing complexity as well as subsequent random movements of the planets in one's Horoscope. These methods are used to inspect the stability and the relationship between the planets in Human Horoscope, which is responsible for every individual's mood, personality and situation depending on the time and place of birth. Insight, the Percolationmethod is used to analyze the motion of the planets based on the pattern formation of planets.A minute difference in degrees of planets placement makes a great differences in each and every individual's life, which is analyzed more appropriately by using ANOVA. [ABSTRACT FROM AUTHOR]

In this paper, we introduced the strong interval valued picture fuzzy graph. The operations on the Cartesian product, Composition, Union and Join of two strong interval valued picture fuzzy graphs are defined. Some propositions are involving strong interval valued picture fuzzy graphs are stated and proved with suitable examples. [ABSTRACT FROM AUTHOR]

In the present study, the numerical analysis of blade tip geometry effect on the performance of a single-stage axial compressor has been the focus of attention. The studied geometries included a rotor with variable tip clearance. For the first model, the tip clearance increases as it moves toward the blade trailing edge. The tip clearance of the second model reduces as it approaches the trailing edge, whereas in the third model, the tip clearance remains constant. The results indicated that the tip clearance of the first sample, as the worst tip clearance case, creates a 10% reduction in the stall margin with respect to the third standard model, and the second sample tip clearance brings about a stall margin reduction of 4% efficiency with respect to the third standard model. Then, the effect of blade tip clearance geometry on outlet flow angle of the rotor was inspected. The results showed that in the first model, the outlet flow angle has the largest deviation than the third standard model and the second model performance places somewhere between the two other tip clearance geometries. Also evident from the result is that taking advantage of the variable blade tip clearance is not an appropriate method for improving compressor performance. [ABSTRACT FROM AUTHOR]

In the last two decades much research works have been performed in order to model the dynamics of highspeed supercavitating projectiles. In the present study, the high speed supercavitating projectiles have been investigated analytically. In this context, the equations of motion were developed for the projectile inside the supercavity. To achieve this purpose, the projectile is described by its mass, geometry and moment of inertia relative to a body-fixed coordinates system. Two experimental based models were used for simulation of supercavity dynamics and the planing force. Furthermore, a detailed parametric study was performed to investigate effect of three main parameters including the mass, cavitator diameter and length of projectile, on the flight performance of a high speed supercavitating projectile. Results obtained in this parametric study can provide some physical insights into high-speed supercavitating projectile design. [ABSTRACT FROM AUTHOR]

In this paper, hull/propeller interaction of a submarine model which has a realistic geometry, in submergence and surface conditions has been studied. For this purpose, the computational fluid dynamics (CFD) method has been used to solve the viscous, incompressible, two phase flow field (in surface condition) around a model of the propeller and submarine hull with and without propeller. The rotation of the propeller has been modeled using the sliding mesh technique. For turbulent flow modeling and free surface simulation, the k-ω SST model and the volume of fluid method (VOF) have been used, respectively. Experimental data obtained from test conducted by the authors in M.U.T. towing tank have been used to validate the numerical scheme. Comparing numerical and experimental results shows good agreement. The experimental and numerical results show that operation of the propeller near water surface reduces the thrust coefficient of the propeller comparing to open water condition, so that according to experimental results the maximum relative reduction of the thrust coefficient is 8.95%. In addition, the results indicated the amount of hull resistance coefficient in surface condition is more than submergence condition. According to the thrust reduction and wake factors obtained from the numerical results, it is known that their values in surface condition are less than submergence condition. This research can be used for more realistic investigation of hull/propeller interaction and thus, more accurate powering performance prediction of submarines. [ABSTRACT FROM AUTHOR]

In the current study, the influence of blade tip clearance in different stages of a three-stage compressor is investigated. Performance diagrams of compressor were verified against experiment when there is no change in the tip clearance, after which the effect of tip clearance for the cases, 1, 1.5 and 2 mm, in the first, second and third stages of rotor was studied. The results indicated that the impact of tip clearance increase did not have any effect on choked flow rate value in the first and second stages, and only the change in the third stage tip clearance reduced the choked flow rate. For the same tip clearance value, the highest compressor performance loss occurs in the case of applying the tip clearance in the third stage, which is also the final stage and is highly sensitive to tip clearance changes. Moreover, modifying the tip clearance is effective on the flow angle in the trailing edge and as the tip clearance increases, the same thing happens about the flow angle. The maximum value of flow angle changes by modifying the tip clearance belongs to the third stage of the compressor. [ABSTRACT FROM AUTHOR]

The hydrodynamic shape of high speed diver propulsion vehicle (DPV) is very important to its performance. One of the basic optimization steps is minimizing DPV drag force to reduce power required. In the present paper, the research has been started by optimization process with a basic design and it would be gradually improved to achieve favorable hydrodynamic characteristics according to diver size and his required volume. The main target is minimizing lift and drag force as objective function. Moreover, this optimization scenario is applicable and it has been followed on the real DPV prototype. The prototype has been constructed and tested in towing tank for results validation. The 3D geometry of a real diver has been created by image processing and software modeling. According to this model the first basic geometry had been designed and then it has been exported to CFD code for steady-state computational analysis. The SST-Kω turbulence model has been selected in the solution to compute hydrodynamic forces. So the position of propulsion system and the shape of vehicle have been improved by repetition process. Output results show that the drag values will be significantly reduced with shape improvement about 51 percent in design speed. [ABSTRACT FROM AUTHOR]