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In this paper, the Flutter analysis of an aircraft wing carrying, elastically, an external store is studied. The wing is considered as a uniform cantilever beam and the external mass is connected to the wing by one spring and damper. The aeroelastic partial governing equations are determined via Hamilton’s variational principle. Also, modified Peter's finite-state aerodynamic model is employed. The resulting partial differential equations are transformed into a set of ordinary differential equations through the assume mode method. Effects of different situations like the wing without external mass, the wing with a rigidly attached external mass, and the wing with an elastically attached external mass on the flutter speed and frequency are investigated. The numerical results for a wing are compared with published results and good agreement is observed. Then, Simulation results for the wing with an elastically attached external mass are presented to show the effects of the wing sweep angle, store mass and its location and the spring rigidity constant on the wing flutter. Results show that sliding the external mass toward the wing tip in spanwise direction and also toward the trailing edge in chordwise direction decreases the flutter speed. Furthermore, increasing the store mass and spring constant decreases the wing flutter speed. Results show that increasing the wing sweep angle, increases the flutter speed, in all situations.

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Ascorbic Acid (AsA) is a water-soluble antioxidant that makes plants resistant to environmental stresses by neutralizing free radicals. However, it is unknown to what extent this antioxidant may help Improve Irrigation Water Use Efficiency (IWUE) and reduce the adverse effects of water deficit on mung bean growth and yield. In an attempt to clarify whether exogenous application of this antioxidant could alleviate the adverse effects of water deficit on mung bean plants, two seasons (2019 and 2020) of field experiments were conducted using twelve combinations of three AsA levels (distilled water as a control and 10 and 20 mM of AsA) and four irrigation water amounts (25, 50, 75, and 100% of the plant water requirement). Based on the results, the maximum IWUE was obtained with W₅₀AsA₂₀ in the two seasons. The beneficial effect of AsA application on IWUE was determined under water stress conditions (W₅₀). High water deficit (W₅₀) plus applying 20 mM ascorbic acid, i.e. W₍₅₀₎AsA₍₂₀₎ treatment, improved seed yield about 43.7% as in the two seasons compared to high water deficit without ascorbic acid, i.e. W₍₅₀₎AsA₍₀₎. In 2019 and 2020, water saving in W₍₅₀₎AsA₍₂₀₎ compared to the control, was equal to 50% (2,550 and 2,500 m³ ha^-1, respectively). In W₍₅₀₎AsA₍₂₀₎ treatment, the increase of seed yield ranged between 79-107% in both seasons. Thus, the results reveal the potency of AsA to save water under low water supply and increase yield in mung bean fields.