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.

Modeling and Performance Evaluation of Nonlinear Satellite Links-A Volterra Series Approach

Abstract: An analytical solution to the problem of modeling bandpass nonlinear channels and evaluating the performance of digital communication systems operating on them is presented. A method based on a Volterra series representation of the overall channel is first proposed, which allows one to extend to nonlinearities with memory the well-known concepts of complex envelope of bandpass signals and low-pass equivalent of bandpass linear systems. The general results previously mentioned are then applied to digital satellite communication systems operating over nonlinear channels. The effect of a nonlinear amplifier located in the satellite is considered, in combination with that of transmitting and receiving filters located in the Earth stations. In addition, both uplink and downlink noise are taken into account. Basic advantages of this approach are the generality it offers to the analysis and the fact that it allows accurate evaluation of the error probability in a short computer time.

Innovation Through Tradition: Lessons From Innovative Family Businesses and Directions for Future Research

Abstract: In steering toward the future, innovation managers are commonly advised to dismiss the old and make way for the new. However, such “recency bias” may significantly limit a firm’s innovation potential and prevent it from realizing the benefits of past knowledge. We argue that the temporal dimension of innovation deserves more research attention. Combining prior research on innovation, dynamic capabilities, and family business, we conceptualize a new product innovation strategy called innovation through tradition (ITT) and identify its underlying capabilities of interiorizing and reinterpreting past knowledge. We analyze and discuss the illustrative cases of six long-lasting family businesses (Aboca, Apreamare, Beretta, Lavazza, Sangalli, and Vibram), exemplifying how firms that build long-lasting and intimate links with their traditions can be extremely innovative while remaining firmly anchored to the past. These examples help readers visualize theoretical concepts and recognize the potential advantages o...

Specification and implementation of exceptions in workflow management systems

Abstract: Although workflow management systems are most applicable when an organization follows standard business processes and routines, any of these processes faces the need for handling exceptions, i.e., asynchronous and anomalous situations that fall outside the normal control flow.In this paper we concentrate upon anomalous situtations that, although unusual, are part of the semantics of workflow applications, and should be specified and monitored coherently; in most real-life applications, such exceptions affect a significant fraction of workflow cases. However, very few workflow management systems are integrated with a highly expressive language for specifying this kind of exception and with a system component capable of handling it. We present Chimera-Exc, a language for the specification of exceptions for workflows based on detached active rules, and then describe the architecture of a system, called FAR, that implements Chimera-Exc and integrates it with a commercial workflow management system and database server. We discuss the main issues that were solved by our implementation, and report on the performance of FAR. We also discuss design criteria for exceptions in light of the formal properties of their execution. Finally, we focus on the portability of FAR on its unbundling to a generic architecture with detached active rules.

Symmetric Galerkin Boundary Element Methods

Abstract: This review article concerns a methodology for solving numerically, for engineering purposes, boundary and initial-boundary value problems by a peculiar approach characterized by the following features: the continuous formulation is centered on integral equations based on the combined use of single-layer and double-layer sources, so that the integral operator turns out to be symmetric with respect to a suitable bilinear form. The discretization is performed either on a variational basis or by a Galerkin weighted residual procedure, the interpolation and weight functions being chosen so that the variables in the approximate formulation are generalized variables in Prager’s sense. As main consequences of the above provisions, symmetry is exhibited by matrices with a key role in the algebraized versions; some quadratic forms have a clear energy meaning; variational properties characterize the solutions and other results, invalid in traditional boundary element methods enrich the theory underlying the computational applications. The present survey outlines recent theoretical and computational developments of the title methodology with particular reference to linear elasticity, elastoplasticity, fracture mechanics, time-dependent problems, variational approaches, singular integrals, approximation issues, sensitivity analysis, coupling of boundary and finite elements, and computer implementations. Areas and aspects which at present require further research are identified, and comparative assessments are attempted with respect to traditional boundary integral-elements. This article includes 176 references.

Charged-particle nuclear modification factors in PbPb and pPb collisions at √sNN=5.02 TeV

Abstract: we acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: BMWFW and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); SENESCYT (Ecuador); MoER, ERC IUT and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NIH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS and RFBR (Russia); MESTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU and SFFR (Ukraine); STFC (United Kingdom); DOE and NSF (U.S.A.).