A Post/Decolonial View of Race and Identity Through the Narratives of U.S. International Students from the Global South

Using postcolonial and decolonial theory as a framework, this study focuses on the lived experiences of international students of color entering the United States for the first time in their lives from the global South. Our goal was to understand how they communicate/perform their dis/located identities in relation to “race” when immersed for the first time in a White settler society context. Findings from this qualitative study underscore discomfort with U.S.-centric race logics, production of ambiguity in relation to identity and race, and the growth of compassion for cultural Others as a result of becoming racial Other. The decolonial implications of such dis-identification with U.S. colonial race categories are discussed.     

The brachistochrone

The brachistochrone problem posed by Bernoulli and its solution highlights one of the most famous experiments in physics which illustrates the variational principle. This pedagogical study is designed to ignite a classroom discussion on the variational problem. We overview the Euler–Lagrange formalism of the variational principle and obtain the solution to the brachistochrone problem. We demonstrate the success of the variational method using brachistochrone models which were fabricated specially for this purpose.     

Electrical rectification

Owing to the saturation of the efficiency of silicon devices in electronics industry, molecular electronics has gained tremendous impetus in recent times. Theoretical predictions and experimental realizations of such systems have given birth to a new generation of miniaturized electronic devices. Organic molecules with delocalized π-electrons show a promising future in this aspect. The long-standing history and interesting properties of two isomeric organic molecules, naphthalene and azulene, motivate us to explore their electrical conductance property and possible electronic device applications that exploit the unique characteristics associated with their structural aspects. Single molecule of azulene shows higher conductivity than naphthalene. The charge transfer from the seven-membered ring to the five-membered ring in azulene gives the system aromatic stability, making it dipolar. As a consequence, the conductance becomes asymmetric for forward and reverse bias, opening an efficient application of azulene as molecular rectifier in electronic device fabrication.     

Inferential statistics made fun: stories that boxes of ‘100 paper clips’ can tell

The natural experiment proposed in this article extracts three stories from boxes of “100 paper clips”. The activity requires students to apply three lessons from inferential statistics, starting with a hypothesis test and including confidence intervals as well as tolerance intervals.     

Nash Bargaining Solution based rendezvous guidance of unmanned aerial vehicles

This paper addresses a finite-time rendezvous problem for a group of unmanned aerial vehicles (UAVs), in the absence of a leader or a reference trajectory. When the UAVs do not cooperate, they are assumed to use Nash equilibrium strategies (NES). However, when the UAVs can communicate among themselves, they can implement cooperative game theoretic strategies for mutual benefit. In a convex linear quadratic differential game (LQDG), a Pareto-optimal solution (POS) is obtained when the UAVs jointly minimize a team cost functional, which is constructed through a convex combination of individual cost functionals. This paper proposes an algorithm to determine the convex combination of weights corresponding to the Pareto-optimal Nash Bargaining Solution (NBS), which offers each UAV a lower cost than that incurred from the NES. Conditions on the cost functions that make the proposed algorithm converge to the NBS are presented. A UAV, programmed to choose its strategies at a given time based upon cost-to-go estimates for the rest of the game duration, may switch to NES finding it to be more beneficial than continuing with a cooperative strategy it previously agreed upon with the other UAVs. For such scenarios, a renegotiation method, that makes use of the proposed algorithm to obtain the NBS corresponding to the state of the game at an intermediate time, is proposed. This renegotiation method helps to establish cooperation between UAVs and prevents non-cooperative behaviour. In this context, the conditions of time consistency of a cooperative solution have been derived in connection to LQDG. The efficacy of the guidance law derived from the proposed algorithm is illustrated through simulations.     

Modelling innovation and imitation sales of products with multiple technological generations

Majority of consumer durables have multiple technological generations. Each succeeding generation offers some innovative performance enhancements, feature additions etc. distinguishing itself from the past releases. Therefore the consumer's attitude towards each of them can be very different. There is a need to understand consumer psychology and have accurate measure to predict the adoption process of new technology. Mathematical models have proved to be ideal tools to explain the past purchasing-behavior and also for forecasting. This paper focuses on studying the relative changes of diffusion parameters for both first time purchasers and upgraders along with developing a more general sales model for multiple technology generation products. The proposed model explicitly identifies different groups of purchaser viz. first timers and repeaters (upgraders).     

GTR component of planetary precession

Even as the theory of relativity is more than a hundred years old, it is not within easy reach of undergraduate students. These students have an insatiable urge to learn more about it even if the full machinery of the tools required to study the same is not within their comfortable reach. The recent detection of gravitational waves has only augmented their enthusiasm about the General Theory of Relativity (GTR), developed just over a hundred years now, encapsulated in Einstein’s Field Equations. The GTR provided a consistent formulation of the theory of gravity, removed the anomalies in the Newtonian model, and predicted spectacular natural phenomena which eventual experiments have testified to. This pedagogical article retraces some of the major milestones that led to the GTR and presents a simple numerical simulation of the GTR advance of the perihelion of planetary motion about the sun.