Instituto Politécnico Nacional

About: Instituto Politécnico Nacional is a education organization based out in Mexico City, Mexico. It is known for research contribution in the topics: Population & Context (language use). The organization has 43351 authors who have published 63315 publications receiving 938532 citations. The organization is also known as: Instituto Politécnico Nacional & Instituto Politecnico Nacional.

Performance analysis of the RPL Routing Protocol

Abstract: The IETF Routing Over Low-power and Lossy Networks working group has recently proposed the IPv6 Routing Protocol for Low power and Lossy Networks, i.e., the RPL protocol. It has been designed to face the typical requirements of wireless sensor networks. Given its relevance in the industrial and scientific communities, this paper presents a performance analysis of RPL based on simulations. Our results clearly show that RPL can ensure a very fast network set-up, thus allowing the development of advanced monitoring applications also in critical conditions. On the other hand, we found that further research is required to optimize the RPL signaling in order to decrease the protocol overhead.

Coastal upwelling activity on the Pacific shelf of the Baja California Peninsula

Abstract: High primary productivity on the Pacific coast of the Baja California Peninsula is usually related to coastal upwelling activity that injects nutrients into the euphotic zone in response to prevailing longshore winds (from the northwest to north). The upwelling process has maximum intensity from April to June, with the coastal upwelling index varying from 50 to 300 m3/s per 100 m of coastline. Along the entire coast of the peninsula, the upwelling intensity changes in accordance with local wind conditions and bottom topography. Spatial variability can also be modulated by the influence of mesoscale meanders of the California Current. We have identified the seasonal and synoptic variability of upwelling signatures on the Baja California shelf, using averaged monthly and weekly sea surface temperature (SST) distributions obtained from remote sensing imagery from the Advanced Very High Resolution Radiometer in the period from 1996 to 2001. Analysis of SST distribution and direct experimental data on temperature and nutrient concentration shows that the areas with the coldest SST anomalies were closely related to the bottom slope, shelf width, and coastline orientation relating to wind direction. We also assume that the nutrient transport into the coastal lagoons may be forced by the coupling of coastal upwelling and tidal pumping of surface waters into the lagoon system.

Search for a charged Higgs boson in pp collisions at s√=8 TeV

Abstract: A search for a charged Higgs boson is performed with a data sample corresponding to an integrated luminosity of 19.7 +/- 0.5 fb(-1) collected with the CMS detector in proton-proton collisions at root s = 8,TeV. The charged Higgs boson is searched for in top quark decays for m(H +/-) t(b)H-+/- for m(H +/-) > m(t) - m(b). The H-+/- -> tau(+/-)nu(tau) and H-+/- -> tb decay modes in the final states tau(h)+jets, mu tau(h), l+jets, and ll' (l =e, mu) are considered in the search. No signal is observed and 95% confidence level upper limits are set on the charged Higgs boson production. A model-independent upper limit on the product branching fraction B(t -> H(+/-)b) B(H-+/- -> tau(+/-)nu(tau)) = 1.2-0.15% is obtained in the mass range m(H +/-) = 80-160 GeV, while the upper limit on the cross section times branching fraction sigma(pp -> t(b)H-+/-) B(H-+/- -> tau(+/-)nu(tau)) = 0.38-0.025 pb is set in the mass range m(H)+ = 180-600 GeV. Here, sigma(pp -> t(b)H-+/-) stands for the cross section sum sigma(pp -> (t) over bar H+) + sigma(pp -> t (b) over bar H-). Assuming B(t -> H(+/-)b) = 1, an upper limit on sigma(pp -> t(b)H-+/-) of 2.0-0.13 pb is set for m(H +/-) = 180-600 GeV. The combination of all considered decay modes and final states is used to set exclusion limits in the m(H +/-)-tan beta parameter space in different MSSM benchmark scenarios.

Observation of electroweak production of same-sign W boson pairs in the two jet and two same-sign lepton final state in proton-proton collisions at s√= 13 TeV

Abstract: The first observation of electroweak production of same-sign W boson pairs in proton-proton collisions is reported The data sample corresponds to an integrated luminosity of 359 fb^(−1) collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC Events are selected by requiring exactly two leptons (electrons or muons) of the same charge, moderate missing transverse momentum, and two jets with a large rapidity separation and a large dijet mass The observed significance of the signal is 55 standard deviations, where a significance of 57 standard deviations is expected based on the standard model The ratio of measured event yields to that expected from the standard model at leading order is 090 ± 022 A cross section measurement in a fiducial region is reported Bounds are given on the structure of quartic vector boson interactions in the framework of dimension-8 effective field theory operators and on the production of doubly charged Higgs bosons