1,924 research outputs found
Performance of wind turbines in a turbulent atmosphere
The effect of atmospheric turbulence on the power fluctuations of large wind turbines was studied. The significance of spatial non-uniformities of the wind is emphasized. The turbulent wind with correlation in time and space is simulated on the computer by Shinozukas method. The wind turbulence is modelled according to the Davenport spectrum with an exponential spatial correlation function. The rotor aerodynamics is modelled by simple blade element theory. Comparison of the spectrum of power output signal between 1-D and 3-D turbulence, shows the significant power fluctuations centered around the blade passage frequency
Installation of fishing net tracking buoys in deep sea multiday tuna drift gillnetters at Chennai
The deep sea multiday tuna drift gillnetters face
many risks while they engage in fishing. The cutting
and stealing of nets by fishermen of other boats
or damage of the nets by the ships is common. As
the total length of a net when set is around 5 to 6
nautical miles (nmi) and the fishing is carried out
during night, quite often the fishermen come to
know about the loss only at the time of hauling
the net. Another serious issue is the possibility of
collision with an approaching ship as sometimes
the fishing ground can be on the same track of a
ship and fishermen notice it only when the ship is
too near to them. Installation of fishing net tracking
buoy can effectively avoid these risks and enable a
hassle free fishing trip
The Schwinger SU(3) construction - I: Multiplicity problem and relation to induced representations
The Schwinger oscillator operator representation of SU(3) is analysed with
particular reference to the problem of multiplicity of irreducible
representations. It is shown that with the use of an unitary
representation commuting with the SU(3) representation, the infinity of
occurrences of each SU(3) irreducible representation can be handled in complete
detail. A natural `generating representation' for SU(3), containing each
irreducible representation exactly once, is identified within a subspace of the
Schwinger construction; and this is shown to be equivalent to an induced
representation of SU(3).Comment: Latex, 25 page
Multi-objective Optimisation of Multi-robot Task Allocation with Precedence Constraints
Efficacy of the multi-robot systems depends on proper sequencing and optimal allocation of robots to the tasks. Focuses on deciding the optimal allocation of set-of-robots to a set-of-tasks with precedence constraints considering multiple objectives. Taguchi’s design of experiments based parameter tuned genetic algorithm (GA) is developed for generalised task allocation of single-task robots to multi-robot tasks. The developed methodology is tested for 16 scenarios by varying the number of robots and number of tasks. The scenarios were tested in a simulated environment with a maximum of 20 robots and 40 multi-robot foraging tasks. The tradeoff between performance measures for the allocations obtained through GA for different task levels was used to decide the optimal number of robots. It is evident that the tradeoffs occur at 20 per cent of performance measures and the optimal number of robot varies between 10 and 15 for almost all the task levels. This method shows good convergence and found that the precedence constraints affect the optimal number of robots required for a particular task level
Metamaterials for light rays: ray optics without wave-optical analog in the ray-optics limit
Volumes of sub-wavelength electromagnetic elements can act like homogeneous
materials: metamaterials. In analogy, sheets of optical elements such as prisms
can act ray-optically like homogeneous sheet materials. In this sense, such
sheets can be considered to be metamaterials for light rays (METATOYs).
METATOYs realize new and unusual transformations of the directions of
transmitted light rays. We study here, in the ray-optics and scalar-wave
limits, the wave-optical analog of such transformations, and we show that such
an analog does not always exist. Perhaps, this is the reason why many of the
ray-optical possibilities offered by METATOYs have never before been
considered.Comment: 10 pages, 3 figures, references update
(R1960) Connectedness and Compactness in Fuzzy Nano Topological Spaces via Fuzzy Nano Z Open Sets
In this paper, we study the notion of fuzzy nano Z connected spaces, fuzzy nano Z disconnected spaces, fuzzy nano Z compact spaces and fuzzy nano Z separated sets in fuzzy nano topological spaces. We also give some properties and theorems of such concepts with connectedness and compactness in fuzzy nano topological spaces
Cloud Based Vehicle Parking System for Anonymous Place Using Internet of Things
The intention of our project is to create a smart parking system for smart cities and malls to find a parking space that is well suited to their respective aspects. That is, it can help in finding either the nearest spot or the best one. Thus the algorithm increases the efficiency of the cloud based system and hence develops a network architecture based on internet of things. We have also successfully implemented the proposed system in the real world
To See or Not to See: Do Front of Pack Nutrition Labels Affect Attention to Overall Nutrition Information?
Citation: Bix, L., Sundar, R. P., Bello, N. M., Peltier, C., Weatherspoon, L. J., & Becker, M. W. (2015). To See or Not to See: Do Front of Pack Nutrition Labels Affect Attention to Overall Nutrition Information? Plos One, 10(10), 20. doi:10.1371/journal.pone.0139732Background Front of pack (FOP) nutrition labels are concise labels located on the front of food packages that provide truncated nutrition information. These labels are rapidly gaining prominence worldwide, presumably because they attract attention and their simplified formats enable rapid comparisons of nutritional value. Methods Eye tracking was conducted as US consumers interacted with actual packages with and without FOP labels to (1) assess if the presence of an FOP label increases attention to nutrition information when viewers are not specifically tasked with nutrition-related goals; and (2) study the effect of FOP presence on consumer use of more comprehensive, traditional nutrition information presented in the Nutritional Facts Panel (NFP), a mandatory label for most packaged foods in the US. Results Our results indicate that colored FOP labels enhanced the probability that any nutrition information was attended, and resulted in faster detection and longer viewing of nutrition information. However, for cereal packages, these benefits were at the expense of attention to the more comprehensive NFP. Our results are consistent with a potential short cut effect of FOP labels, such that if an FOP was present, participants spent less time attending the more comprehensive NFP. For crackers, FOP labels increased time spent attending to nutrition information, but we found no evidence that their presence reduced the time spent on the nutrition information in the NFP. Conclusions The finding that FOP labels increased attention to overall nutrition information by people who did not have an explicit nutritional goal suggests that these labels may have an advantage in conveying nutrition information to a wide segment of the population. However, for some food types this benefit may come with a short-cut effect; that is, decreased attention to more comprehensive nutrition information. These results have implications for policy and warrant further research into the mechanisms by which FOP labels impact use of nutrition information by consumers for different foods
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