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Luckert F.,University of Strathclyde | Yakushev M.V.,University of Strathclyde | Faugeras C.,UPS | Karotki A.V.,National Academy of Sciences of Belarus | And 3 more authors.
Applied Physics Letters | Year: 2010

Single crystals of CuGaSe2 were studied using magnetophotoluminescence in magnetic fields up to 20 T at 4.2 K. The rate of the diamagnetic shift in the A free exciton peak was determined to be 9.82× 10-6 eV/ T2. This rate was used to calculate the reduced mass as 0.115 m0, the binding energy as 12.9 meV, the Bohr radius as 5.1 nm and an effective hole mass of 0.64 m0 (m0 is the free electron mass) of the free A exciton using a low-field perturbation approach and the hydrogenic model. © 2010 American Institute of Physics.

Pillajo C.,Polytechnic University of Mozambique | Hincapie R.,Pontifical Bolivarian University | Pilatasig E.,UPS
CHILECON 2015 - 2015 IEEE Chilean Conference on Electrical, Electronics Engineering, Information and Communication Technologies, Proceedings of IEEE Chilecon 2015 | Year: 2015

Today there are many designs and applications involving communication, control and computing. These applications generate network control systems, which are systems composed of a lot of integrated entities, sensor nodes coupled through a common communication network for manipulation and physical control processes, as well as robotic devices, network control systems are generating applications that are becoming ubiquitous and useful in several areas such as health care, disaster management, flexible manufacturing, education, etc., but network control systems implementation still faces several challenges such as cost and efficiency of resources. This work focuses on the implementation of a cloud service for remote control of a robotic manipulator, that develops an infrastructure (IaaS) for the robotic arm, a service is programmed in C J (PaaS) that gives access to remote users (SaaS) to create a MRaaS unit, finally an optimal control model restriction and control event-triggered communication are studied to be applied to a Robotic Manipulator as a Service. © 2015 IEEE.

The predicted increase in atmospheric CO 2 concentration for this century is expected to lead to increases in temperature and changes in litter quality that can affect small woodland streams, where water temperature is usually low and allochthonous organic matter constitutes the basis of the food web. We have assessed the individual and interactive effect of water temperature (5 and 10°C) and alder litter quality produced under ambient CO 2 levels (ambient litter) or under CO 2 concentrations predicted for 2050 (elevated litter) on litter decomposition and on fungal activity and assemblage structure. Litter decomposition rates and fungal respiration rates were significantly faster at 10 than at 5°C, but they were not affected by litter quality. Litter quality affected mycelial biomass accrual at 5 but not at 10°C, while increases in temperature stimulated biomass accrual on ambient but not on elevated litter. A similar pattern was observed for conidial production. All variables were stimulated on elevated litter at 10°C (future scenario) compared with ambient litter at 5°C (present scenario), but interactions between temperature and litter quality were additive. Temperature was the factor that most strongly affected the structure of aquatic hyphomycete assemblages. Our results indicate that if future increases in atmospheric CO 2 lead to only slight modifications in litter quality, the litter decomposition and fungal activities and community structure will be strongly controlled by increased water temperature. This may have serious consequences for aquatic systems as faster litter decomposition may lead to food depletion for higher trophic levels. © 2011 Springer-Verlag.

Kang D.-H.,Duke University | Kang D.-H.,Korea Advanced Institute of Science and Technology | Lorente S.,UPS | Bejan A.,Duke University
International Journal of Energy Research | Year: 2013

Here, we show how to distribute multiple layers of insulation along a nonisothermal enclosure so that the total heat loss is minimal. The types and total amounts of insulation materials are fixed. Variables are the thicknesses of the insulation layers, their relative amounts, the temperature of the insulated surface, and the cross-sectional area of the enclosure. We show that, first, the structure of the multi-layer insulation must be such that the thicknesses of all the layers vary in the same way in the longitudinal direction x. Second, the x dependence of the enclosure cross-sectional area has a significant effect on the heat loss reduction associated with using the distributed insulation design. Greater reductions in heat loss are obtained when the enclosure is tapered such that it is narrower in the direction of the warm end. Third, the x dependence of the temperature distribution along the insulated wall has a significant effect on the reduction in heat loss through reduction in heat loss through the multi-layer insulation. Greater reductions are obtained when the wall temperature distribution is more convex. Even greater reductions in heat loss are possible when the three design features summarized previously are implemented simultaneously. © 2011 John Wiley & Sons, Ltd.

Sinha M.,UPS
Appropriate Technology | Year: 2010

Ten villages in Karnataka, India, have switched to solar power due to power shortages. Solar lighting has sustained activities in these villages even after sunset. Karnataka Vikas Grameena Bank (KVGB) is a leading rural bank in Karnataka and started introducing solar lighting in the villages in 1994. KVGB has been more than a bank as they have informed villagers about the significance of solar lamps both economically and ecologically. Solar lamps do not mean just better health and hygiene, but also more studying hours for children in the villages. Farmers often get favorable terms so that more can benefit, and in some villages farmers have had their loans paid by civil society organizations. Branch managers visit the villages after their office hours and hold group meetings. People have realized the value of renewable energy. They own it and are passing the message to others.

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