Institution
Instituto Politécnico Nacional
Education•Mexico City, Mexico•
About: Instituto Politécnico Nacional is a education organization based out in Mexico City, Mexico. It is known for research contribution in the topics: Population & Control theory. 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.
Topics: Population, Control theory, Thin film, Catalysis, Nonlinear system
Papers published on a yearly basis
Papers
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01 Sep 2009TL;DR: The characteristic features, advantages, and limiting factors of the existing CR MAC protocols are thoroughly investigated for both infrastructure-based and ad hoc networks, highlighting the close coupling of the MAC protocol design with the other layers of the protocol stack.
Abstract: In cognitive radio (CR) networks, identifying the available spectrum resource through spectrum sensing, deciding on the optimal sensing and transmission times, and coordinating with the other users for spectrum access are the important functions of the medium access control (MAC) protocols. In this survey, the characteristic features, advantages, and the limiting factors of the existing CR MAC protocols are thoroughly investigated for both infrastructure-based and ad hoc networks. First, an overview of the spectrum sensing is given, as it ensures that the channel access does not result in interference to the licensed users of the spectrum. Next, a detailed classification of the MAC protocols is presented while considering the infrastructure support, integration of spectrum sensing functionalities, the need for time synchronization, and the number of radio transceivers. The main challenges and future research directions are presented, while highlighting the close coupling of the MAC protocol design with the other layers of the protocol stack.
487 citations
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TL;DR: The notion of perfect space-time block codes (STBCs) are introduced and algebraic constructions of perfect STBCs for 2, 3, 4, and 6 antennas are presented.
Abstract: In this paper, we introduce the notion of perfect space-time block codes (STBCs). These codes have full-rate, full-diversity, nonvanishing constant minimum determinant for increasing spectral efficiency, uniform average transmitted energy per antenna and good shaping. We present algebraic constructions of perfect STBCs for 2, 3, 4, and 6 antennas
483 citations
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TL;DR: A model is proposed in which auxin sensitivity is enhanced in Pi-deprived plants by an increased expression of TIR1, which accelerates the degradation of AUX/IAA proteins, thereby unshackling ARF transcription factors that activate/repress genes involved in LR formation and emergence.
Abstract: The survival of plants, as sessile organisms, depends on a series of postembryonic developmental events that determine the final architecture of plants and allow them to contend with a continuously changing environment. Modulation of cell differentiation and organ formation by environmental signals has not been studied in detail. Here, we report that alterations in the pattern of lateral root (LR) formation and emergence in response to phosphate (Pi) availability is mediated by changes in auxin sensitivity in Arabidopsis thaliana roots. These changes alter the expression of auxin-responsive genes and stimulate pericycle cells to proliferate. Modulation of auxin sensitivity by Pi was found to depend on the auxin receptor TRANSPORT INHIBITOR RESPONSE1 (TIR1) and the transcription factor AUXIN RESPONSE FACTOR19 (ARF19). We determined that Pi deprivation increases the expression of TIR1 in Arabidopsis seedlings and causes AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) auxin response repressors to be degraded. Based on our results, we propose a model in which auxin sensitivity is enhanced in Pi-deprived plants by an increased expression of TIR1, which accelerates the degradation of AUX/IAA proteins, thereby unshackling ARF transcription factors that activate/repress genes involved in LR formation and emergence.
482 citations
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477 citations
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TL;DR: In this article, the authors present some reflections regarding the adequate requirements and issues enabling organizations to be efficient, and fully operational in Logistics 4.0 context, where the emergence of the Industry Internet of Things (IIoT) promoted new challenges in logistic domain, which might require technological changes such as: high need for transparency (supply chain visibility); integrity control (right products, at right time, place, quantity condition and at the right cost).
477 citations
Authors
Showing all 43548 results
Name | H-index | Papers | Citations |
---|---|---|---|
Giacomo Bruno | 158 | 1687 | 124368 |
Giuseppe Mancia | 145 | 1369 | 139692 |
Giorgio Maggi | 135 | 1323 | 90270 |
Salvatore Nuzzo | 133 | 1533 | 91600 |
Giuseppe Iaselli | 133 | 1514 | 91558 |
Marcello Abbrescia | 132 | 1400 | 84486 |
Louis Antonelli | 132 | 1089 | 83916 |
Donato Creanza | 132 | 1452 | 89206 |
Alexis Pompili | 131 | 1437 | 86312 |
Gabriella Pugliese | 131 | 1309 | 88714 |
Giovanna Selvaggi | 131 | 1159 | 83274 |
Heriberto Castilla-Valdez | 130 | 1659 | 93912 |
Ricardo Lopez-Fernandez | 129 | 1213 | 81575 |
Cesare Calabria | 128 | 1095 | 76784 |
Paolo Vitulo | 128 | 1120 | 79498 |