Forward to the next mission

Nowadays, the greatest challenge that the educational system faces is the way we learn. This leads to the need for coming up with much better methods in order to develop and form and turn into habit key life skills, also known as ‘21st century skills’, (problem solving, creativity, teamwork, communication, initiative, leadership, adaptability, etc.). A successful way to accomplish this is project-based learning. The missions that are part of the ‘Design thinking’ method are an innovative way for its implementation. Therefore, this method is being used during the school year of 2020/2021 in Bacho Kiro High School, town of Pavlikeni, as part of a project under which turned the school into innovative. ‘Design thinking’ is a process which can be applied to everything that has to be produced, created or solved. This method helps younger pupils organize information and ideas in a better way, understand other people’s point of view and their problems more clearly, manage to lay down challenges accurately, think of more creative ideas and find quick ways to put them into practice. Every realized activity or ‘Design thinking’ project helps pupils understand that they can face unknown challenges as a team and find new solutions. There are seven missions for a single school year. There is one mission in a month, each in five consecutive days for 2 hours a day. Thanks to their creators from the Red Paper Plane, pupils became architects, space-men and discoverers. They await to become ecologists, travelers, meteorologists and automobile designers. All pupils, teachers and parents together have embarked on an incredible journey on the wings of the red paper plane so that the pupils from Bacho Kiro High School, town of Pavlikeni, are happy and successful in the 21st century.

Aerodynamic Performances of Paper Planes

Paper plane has a high potential to be upgraded as a Micro Air Vehicle (MAV). Due to its simplicity, paper plane offers easier design option compared to the biological inspired designs as shown in recent MAV development. However, researchers have underestimate and overlook the basic aerodynamic performance induced by these paper planes. This is due to its common usage as toys and wide range of paper plane design. Thus, the objective for current work is to analyse and compare the aerodynamics forces and its performance for selected paper plane design known as Glider, Wide Stunt Glider Plane and Stunt plane. A series of CFD simulations on each paper plane was executed by using ANSYS-CFX module. A steady state, incompressible flow Navier-Stokes equation (RANS) combined with Shear Stress Turbulence (SST) model were used in this works to solve flow problem over the paper planes. The analysis is mainly conducted to study and compare the lift coefficient (), drag coefficient ()and aerodynamic efficiency () performances for each paper planes. The results show that the Glider paper plane has managed to produce better performances in terms overall magnitude, stall angle, wider angle of attack (?) envelope and higher maximum lift coefficient magnitude compared to the other paper plane design. However, Glider paper plane has the least distributions by producing at least 14.3% larger magnitude compared to the other plane design at certain ? region. Instead, The Wide Stunt has promisingly produced better distribution by producing lower value compared to the other plane design. Based on performance, the Wide Stunt paper plane has produced better and maximum aerodynamic efficiency () magnitudes compared to the other design. Wide Stunt paper plane induced at least 6.4% better magnitude compared to the other paper plane design. Based on these results, it can be concluded that Wide Stunt paper plane has promising advantages which are very crucial for the paper plane especially during hovering operation, take-off and landing manoeuvre.

The aerodynamic optimisation of a low-Reynolds paper plane with adjoint method

ABSTRACT The aerodynamic performance of a deployable and low-cost unmanned aerial vehicle (UAV) is investigated and improved in present work. The parameters of configuration, such as airfoil and winglet, are determined via an optimising process based on a discrete adjoint method. The optimised target is locked on an increasing lift-to-drag ratio with a limited variation of pitching moments. The separation that will lead to a stall is delayed after optimisation. Up to 128 design variables are used by the optimised solver to give enough flexibility of the geometrical transformation. As much as 20% enhancement of lift-to-drag ratio is gained at the cruise angle-of-attack, that is, a significant improvement in the lift-to-drag ratio adhering to the preferred configuration is obtained with increasing lift and decreasing drag coefficients, essentially entailing an improved aerodynamic performance.

Using artificial neural network on flight distance prediction for paper plane

This study shows how to apply the essential principles of paper plane on the flight experiment. It applies three basic structures of paper plane including nose, wing, and rudder movements to predict the optimal flight distance. This study employs the artificial neural network model for data analysis and prediction. The data collected from the flight distance of paper plane are calculated and analyzed in the artificial neural network model in order to predict the optimal flight distance of paper plane. This study is intended to discover the essential principles and basic structures of manufacturing paper plane and provide theoretical and practical contributions in hands-on experiments and aviation science.

Oxatriquinane Derivatives: A Theoretical Investigation of SN1-SN2 Reactions Borderline

This study investigated the nucleophilic substitution reaction mechanisms of 5 oxatriquinane derivatives, namely: oxatriquinane (OTQ), 1,4,7-trimethyloxatriquinane (TMO), 1,4,7-triethyloxatriquinane (TEO), 1,4,7-tri-iso-propyloxatriquinane (TIO) and 1,4,7-tri-tert-butyloxatriquinane (TTO). In addition to the G3 conformation (one with the substituent groups at 1,4 and 7 positions pointing into the plane of the paper) originally proposed by the previous workers, Mascal et al. in 2008 and Gunbas et al. in 2013, one more geometrical isomer was considered again for each of the derivatives, the 2G1 isomer (one in which only 2 of the 3 substituent groups at 1,4 and 7 positions are into the paper plane). Geometry optimization and determination of transition state properties of the conformers corresponding to each molecule (in the presence of azide ion, N3-) provided theoretical evidences on the possible reaction mechanisms. The 2G1 conformer for TTO was found to be unstable. The reactions of OTQ, TMO and TEO with azide ion (N3-) followed SN2 pathway, with SN1mechanism completely lacking. This finding is in agreement with the first set of reports published on this subject in 2008 and 2010 by Mascal’s group. For TIO (in the presence of azide ion), only the presence of SN1 mechanism could be proved without any observation of transition state (TS), even though, it possesses a 2G1 conformer. TTO surprisingly, showed marked evidence of SN1 mechanism also without any evidence of TS. The results obtained showed that OTQ derivatives up to TEO undergo nucleophilic substitution predominantly via SN2, and above which (i.e. for TIO and TTO) the mechanisms predominantly become SN1.

Plane wave propagation in a rotating anisotropic medium with voids under the action of a uniform magnetic field

In this paper, plane wave propagation in a rotating anisotropic material of general nature under the action of a magnetic field of constant magnitude has been investigated. The material is supposed to be porous in nature and contains voids. Following the concept of [Cowin S. C. and Nunziato, J. W. [1983] “Linear elastic materials with voids,” J. Elasticity 13, 125–147.] the governing equations of motion have been written in tensor notation taking account of rotation, magnetic field effect and presence of voids in the medium and the possibility of plane wave propagation has been examined. A number of particular cases have been derived from our general results to match with previously obtained results in this area. Effects of various parameters on the velocity of wave propagation have been presented graphically.