Closed loop models for analyzing the effects of simulator characteristics

The optimal control model of the human operator is used to develop closed loop models for analyzing the effects of (digital) simulator characteristics on predicted performance and/or workload. Two approaches are considered: the first utilizes a continuous approximation to the discrete simulation in conjunction with the standard optimal control model; the second involves a more exact discrete description of the simulator in a closed loop multirate simulation in which the optimal control model simulates the pilot. Both models predict that simulator characteristics can have significant effects on performance and workload

Exploring Packaging Strategies of Nano-embedded Thermoelectric Generators

Embedding nanostructures within a bulk matrix is an important practical approach towards the electronic engineering of high performance thermoelectric systems. For power generation applications, it ideally combines the efficiency benefit offered by low dimensional systems along with the high power output advantage offered by bulk systems. In this work, we uncover a few crucial details about how to embed nanowires and nanoflakes in a bulk matrix so that an overall advantage over pure bulk may be achieved. First and foremost, we point out that a performance degradation with respect to bulk is inevitable as the nanostructure transitions to being multi moded. It is then shown that a nano embedded system of suitable cross-section offers a power density advantage over a wide range of efficiencies at higher packing fractions, and this range gradually narrows down to the high efficiency regime, as the packing fraction is reduced. Finally, we introduce a metric - \emph{the advantage factor}, to elucidate quantitatively, the enhancement in the power density offered via nano-embedding at a given efficiency. In the end, we explore the maximum effective width of nano-embedding which serves as a reference in designing generators in the efficiency range of interest.Comment: 10 pages, 8 figure

Closed loop models for analyzing engineering requirements for simulators

A closed loop analytic model, incorporating a model for the human pilot, (namely, the optimal control model) that would allow certain simulation design tradeoffs to be evaluated quantitatively was developed. This model was applied to a realistic flight control problem. The resulting model is used to analyze both overall simulation effects and the effects of individual elements. The results show that, as compared to an ideal continuous simulation, the discrete simulation can result in significant performance and/or workload penalties

Plants used for topical application from Gingee hills, Tamil Nadu, India.

This study is a documentation of medicinal plants used for topical applications by villagers around Gingee hills of Villupuram District, Tamil Nadu, India. A total of 23 Dicot plants belong to 18 families are used as topical applications to treat various skin diseases such as sore, psoriasis, itching, scabies, eczema and other skin infections. Herbs (8 species) are the dominant life form category equal number of shrubs and trees (6 species) followed by 3 species of climbers. Generally fresh plant parts are used in the form of powder, extract and paste. Leaves are the mostly used part in the preparation of medicine. The present study concluded that the abundance of medicinally important plants is an excellent potential for discovery of novel drugs to cure various ailments

Efficient long distance quantum communication

Despite the tremendous progress of quantum cryptography, efficient quantum communication over long distances (>1000km) remains an outstanding challenge due to fiber attenuation and operation errors accumulated over the entire communication distance. Quantum repeaters, as a promising approach, can overcome both photon loss and operation errors, and hence significantly speedup the communication rate. Depending on the methods used to correct loss and operation errors, all the proposed QR schemes can be classified into three categories (generations). Here we present the first systematic comparison of three generations of quantum repeaters by evaluating the cost of both temporal and physical resources, and identify the optimized quantum repeater architecture for a given set of experimental parameters. Our work provides a roadmap for the experimental realizations of highly efficient quantum networks over transcontinental distances.Comment: Sreraman Muralidharan and Linshu Li contributed equally to this wor

Rectification by charging -- the physics of contact-induced current asymmetry in molecular conductors

We outline the qualitatively different physics behind charging-induced current asymmetries in molecular conductors operating in the weakly interacting self-consistent field (SCF) and the strongly interacting Coulomb Blockade (CB) regimes. A conductance asymmetry arises in SCF because of the unequal mean-field potentials that shift a closed-shell conducting level differently for positive and negative bias. A very different current asymmetry arises for CB due to the unequal number of open-shell excitation channels at opposite bias voltages. The CB regime, dominated by single charge effects, typically requires a computationally demanding many-electron or Fock space description. However, our analysis of molecular Coulomb Blockade measurements reveals that many novel signatures can be explained using a {{simpler}} orthodox model that involves an incoherent sum of Fock space excitations and {\it{hence treats the molecule as a metallic dot or an island}}. This also reduces the complexity of the Fock space description by just including various charge configurations only, thus partially underscoring the importance of electronic structure, while retaining the essence of the single charge nature of the transport process. We finally point out, however, that the inclusion of electronic structure and hence well-resolved Fock space excitations is crucial in some notable examples.Comment: 12 pages, 10 figure

Analyzing the trade competitiveness of Indian coconut sector in the liberalization regime

Coconut export sector in India of late gained an outward orientation, especially since the Coconut Development Board was elevated to the status of export promotion council in the year 2009. In the recent period, the growth rate experienced in the coconut based value added products has been stupendous. Since there is an attempt for global value chain up-gradation at the production node of the sector, it is imperative to analyse our strengths in the world market in comparison with the major competitors. We have used the Revealed Comparative Advantage (RCA) methodology to analyse India’s competitiveness in the exports of major coconut value added products traded across the world. The study revealed that, as far as the coconut value added products are concerned, India is comparatively a very small player with paltry export market shares. The analysis of RCA revealed that comparative advantage of India is lower than the major coconut exporting countries like Philippines, Indonesia and Sri Lanka. The Philippines is the dominant player with highest RCA indices in most of the coconut value added product lines. The study suggests the need to formulate plausible strategies to reach the overseas market and capture the optimal share in market segments. Though we have a strong domestic market base, it is an indubitable fact that in the near future due to the evolving trade agreements even in the domestic sector we may confront fierce price competition from the overseas imports. Hence we need to chalk out modalities and execution plans to elevate our export competitiveness and comparative advantage

Group approach for enhancing profitability of small holders through technology integration-reflections from coconut farming

Technology integration for enhancing productivity and income from coconut farming, facilitated through stakeholder participation, was a major objective of the NAIP sub-project on ‘Value chain in coconut’ implemented in a consortium mode with ICAR-Central Plantation Crops Research Institute, Kasaragod as the lead institute. To achieve this objective, 10 clusters of coconut farmers were formed under the project in selected panchayats of Kasaragod district in Kerala state. A total of 534 farmers covering 250 ha participated in the project interventions. Appropriate production technologies were integrated in their holdings which included intercropping, growing of leguminous crops in the coconut basin, organic recycling through vermicomposting and integrated nutrient management. Group action was initiated among the farmers for taking up need-based integrated disease management measures especially to control bud rot disease of coconut. Knowledge and skill upgradation of farmers on the selected technologies were achieved through various institutional and off campus training programmes. The net income from the coconut farming in small and marginal holdings could be increased through the interventions under the project. Technology integration in the holdings also resulted in the increase of coconut productivity from 60 to 112 nuts per palm. Technology integration in small and marginal coconut holdings for higher productivity and income through Community Based Organizations approach is scaled up by other agencies like Coconut Development Board for implementing development/extension programmes