Effect of chemical substitution in Rh17S15

Rh17S15 has recently been shown to be a strongly correlated superconductor with a transition temperature of 5.4 K. In order to understand the nature of strong correlations we study the effect of substitution of some of the Rh and S atoms by other elements such as Fe, Pd, Ir and Ni on the Rh side and Se on the S side in this work. We find that while substitution of Ir and Se lower the transition temperature considerably, that of Fe, Pd and Ni destroy superconductivity down to 1.5 K. The resistivity data in these doped samples show a minimum which is presumably disorder induced. A reduction of Tc is always accompanied by a reduction of electron correlations as deduced from heat capacity and magnetization data. Interestingly, the Fe doped sample shows some possible antiferromagnetic ordering at low temperatures.Comment: Published in Journal of Physics Condensed Matte

Accurately and Efficiently Interpreting Human-Robot Instructions of Varying Granularities

Humans can ground natural language commands to tasks at both abstract and fine-grained levels of specificity. For instance, a human forklift operator can be instructed to perform a high-level action, like "grab a pallet" or a low-level action like "tilt back a little bit." While robots are also capable of grounding language commands to tasks, previous methods implicitly assume that all commands and tasks reside at a single, fixed level of abstraction. Additionally, methods that do not use multiple levels of abstraction encounter inefficient planning and execution times as they solve tasks at a single level of abstraction with large, intractable state-action spaces closely resembling real world complexity. In this work, by grounding commands to all the tasks or subtasks available in a hierarchical planning framework, we arrive at a model capable of interpreting language at multiple levels of specificity ranging from coarse to more granular. We show that the accuracy of the grounding procedure is improved when simultaneously inferring the degree of abstraction in language used to communicate the task. Leveraging hierarchy also improves efficiency: our proposed approach enables a robot to respond to a command within one second on 90% of our tasks, while baselines take over twenty seconds on half the tasks. Finally, we demonstrate that a real, physical robot can ground commands at multiple levels of abstraction allowing it to efficiently plan different subtasks within the same planning hierarchy.Comment: Updated with final version - Published as Conference Paper in Robotics: Science and Systems 201

Whale shark, Rhinocodon typus (Smith) landed at Tuticorin, Gulf of Mannar

Paper is reporting the morphometric measurements of a male whale shark Rhinocodon typus measuring 4.45 m and weighing approximately 1.5 t got entangled in a nylon net at a depth of 90-100 m,operated for tuna and allied species

Manta birostris landed at Tuticorin

On 31.03.2006 one female Manta birostris measuring 370 cm in total length 620 cm in breadth and weighing 1550 kg was caught by "singi valai" (a type of bottom set gill net) from a depth of 40 m off Tuticorin and brought to Tuticorin north landing centre

To mesh or not to mesh: flexible wireless indoor communication among mobile robots in industrial environments

Mobile robots such as automated guided vehicles become increasingly important in industry as they can greatly increase efficiency. For their operation such robots must rely on wireless communication, typically realized by connecting them to an existing enterprise network. In this paper we motivate that such an approach is not always economically viable or might result in performance issues. Therefore we propose a flexible and configurable mixed architecture that leverages on mesh capabilities whenever appropriate. Through experiments on a wireless testbed for a variety of scenarios, we analyse the impact of roaming, mobility and traffic separation and demonstrate the potential of our approach