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Conocer la historia y la evolución que ha tenido la seguridad privada en Colombia, permite percibir un panorama amplio del sector que pese al alto riesgo que significa tanto para prestadores como para usuarios del servicio, ha tenido una transformación en el tiempo; esto, asociado a la situación de conflicto interno del país, a los avances tecnológicos y la formulación de la política en materia de vigilancia y seguridad privada, que como consecuencia exige en la dinámica de oferta y demanda en el mercado laboral, el mejoramiento de los servicios bajo estándares de calidad que respondan a las necesidades y exigencias del contexto actual. Lo anterior conduce a la Superintendencia de Vigilancia y Seguridad Privada del país, a robustecer los procedimientos en cumplimiento de sus funciones para alcanzar los objetivos previstos para el territorio nacional, con base en los estándares de calidad que se vienen aplicando para el mejoramiento del servicio bajo normas como: ISO 9001 (SGC), BASC, y OHSAS 18001; así mismo, se hace referencia a la importancia que tiene la seguridad integral para alcanzar un efectivo desarrollo desde las diferentes dinámicas del país. Resumen 4 Abstract 5 Introducción 7 Hipótesis 9 Objetivos 9 Objetivo general 9 Objetivos específicos 9 Capítulo I. Gestión de calidad en los servicios de seguridad privada en Colombia 10 Capítulo II. La implementación de la gestión de calidad bajo la norma ISO 9001 en las empresas de seguridad privada en Colombia 12 Capítulo III. Importancia de la implementación del Sistema de gestión de calidad bajo los lineamientos de la Norma ISO 9001:2015 en el servicio de seguridad privada en Colombia. Conclusiones 17 Referencias Bibliográficas 22 Anexos 25 Conocer la historia y la evolución que ha tenido la seguridad privada en Colombia, permite percibir un panorama amplio del sector que pese al alto riesgo que significa tanto para prestadores como para usuarios del servicio, ha tenido una transformación en el tiempo; esto, asociado a la situación de conflicto interno del país, a los avances tecnológicos y la formulación de la política en materia de vigilancia y seguridad privada, que como consecuencia exige en la dinámica de oferta y demanda en el mercado laboral, el mejoramiento de los servicios bajo estándares de calidad que respondan a las necesidades y exigencias del contexto actual. Lo anterior conduce a la Superintendencia de Vigilancia y Seguridad Privada del país, a robustecer los procedimientos en cumplimiento de sus funciones para alcanzar los objetivos previstos para el territorio nacional, con base en los estándares de calidad que se vienen aplicando para el mejoramiento del servicio bajo normas como: ISO 9001 (SGC), BASC, y OHSAS 18001; así mismo, se hace referencia a la importancia que tiene la seguridad integral para alcanzar un efectivo desarrollo desde las diferentes dinámicas del país. Pregrado

The core and backbone optical network market segment is largely dominated by coherent transmission delivering 100Gbps and beyond thanks to the DSP-based coherent transceivers technology optical line systems without chromatic dispersion compensation. The metro and access segment instead is still often made of dispersion-compensated optical line systems operated with cheap 10G transceivers because of the still excessive CAPEX required to upgrade this segment to coherent technology. In the context of the gradual rise of SDN technology, aimed at dynamically, transparently and automatically managing and orchestrating optical networks, the ability to route 100G coherent channels through a section of dispersion managed network populated with legacy 10G channels enables more flexibility and CAPEX savings. In this work we propose a simple, fast and conservative quality-of-transmission estimator, tailored to the needs of a software module for optical path computation, able to estimate of the 10G-to-100G non-linear effects.

We report on the observation of time-resolved quantum beats in the helium fluorescence from the transition 1s3p -> 1s2s, where the initial state is excited by XUV free-electron laser radiation. The quantum beats originate from the Zeeman splitting of the magnetic substates due to an external magnetic field. We perform a systematic study of this effect and discuss the possibilities of studying this phenomenon in the XUV and x-ray regime., 7 pages, 4 figures

Soil moisture estimation with synthetic aperture radar (SAR) images is currently based on the amplitude of backscattered signal. However, there are evidences that soil or vegetation moisture can influence the SAR interferometric phase (InSAR), in fact, moisture effects are suspected to be a considerable nuisance when the goal is the precise estimation of ground deformation using InSAR. A moisture retrieval method based on the interferometric phase, both for improving ground deformation and surface moisture measurements, has in the past been presented and to some extend validated. In this paper we will show our first inversion results based on Sentinel-1 C-band images; we compare incoherent and coherent methods; we conclude that the possibility of integrating incoherent and coehrent soil moisture estimation is becoming realistic and should therefore be thoroughly investigated.

We show how to compute classical wave observables using quantum scattering amplitudes. We discuss observables both with incoming and with outgoing waves. The required classical limits are naturally described by coherent states of massless bosons. We recompute the classic gravitational deflection of light, and also show how to rederive Thomson scattering. We introduce a new class of local observables, which includes the asymptotic electromagnetic and gravitational Newman--Penrose scalars. As an example, we compute a simple radiated waveform: the expectation of the electromagnetic field in charged-particle scattering. At leading order, the waveform is trivially related to the five-point scattering amplitude., Comment: 84 pages, 3 figures

Significance High-Q mechanical modes of transverse oscillation at a few megahertz are characterized for a photonic crystal waveguide (PCW) consisting of parallel dielectric nanobeams. The transduction of thermally excited motion of 33 pm at 300 K results in phase modulation with high signal-to-noise ratio for light propagating in a guided mode of the PCW. Numerical modeling gives good agreement with experiment. With these measurements in hand, the system is assessed for possible applications in quantum information science and technology involving strong coupling of single phonons of vibration to single atoms and photons trapped within the PCW., Observations of thermally driven transverse vibration of a photonic crystal waveguide (PCW) are reported. The PCW consists of two parallel nanobeams whose width is modulated symmetrically with a spatial period of 370 nm about a 240-nm vacuum gap between the beams. The resulting dielectric structure has a band gap (i.e., a photonic crystal stop band) with band edges in the near infrared that provide a regime for transduction of nanobeam motion to phase and amplitude modulation of an optical guided mode. This regime is in contrast to more conventional optomechanical coupling by way of moving end mirrors in resonant optical cavities. Models are developed and validated for this optomechanical mechanism in a PCW for probe frequencies far from and near to the dielectric band edge (i.e., stop band edge). The large optomechanical coupling strength predicted should make possible measurements with an imprecision below that at the standard quantum limit and well into the backaction-dominated regime. Since our PCW has been designed for near-field atom trapping, this research provides a foundation for evaluating possible deleterious effects of thermal motion on optical atomic traps near the surfaces of PCWs. Longer-term goals are to achieve strong atom-mediated links between individual phonons of vibration and single photons propagating in the guided modes (GMs) of the PCW, thereby enabling optomechanics at the quantum level with atoms, photons, and phonons. The experiments and models reported here provide a basis for assessing such goals.

We present a systematic geometric framework to study closed quantum systems based on suitably chosen variational families. For the purpose of (A) real time evolution, (B) excitation spectra, (C) spectral functions and (D) imaginary time evolution, we show how the geometric approach highlights the necessity to distinguish between two classes of manifolds: K\"ahler and non-K\"ahler. Traditional variational methods typically require the variational family to be a K\"ahler manifold, where multiplication by the imaginary unit preserves the tangent spaces. This covers the vast majority of cases studied in the literature. However, recently proposed classes of generalized Gaussian states make it necessary to also include the non-K\"ahler case, which has already been encountered occasionally. We illustrate our approach in detail with a range of concrete examples where the geometric structures of the considered manifolds are particularly relevant. These go from Gaussian states and group theoretic coherent states to generalized Gaussian states., Comment: Submission to SciPost, 47+10 pages, 8 figures

Composite spectrum (CS) is a data-fusion technique that reduces the number of spectra to be analyzed, simplifying the analysis process for machine monitoring and fault detection. In this work, vibration signals from five components of a combine harvester (thresher, chopper, straw walkers, sieve box, and engine) are obtained by placing four accelerometers along the combine-harvester chassis in non-optimal locations. Four individual spectra (one from each accelerometer) and three CS (non-coherent, coherent and poly-coherent spectra) from 18 cases are analyzed. The different cases result from the combination of three working conditions of the components&mdash, deactivated (off), balanced (healthy), and unbalanced (faulty)&mdash, and two speeds&mdash, idle and maximum revolutions per minute (RPM). The results showed that (i) the peaks can be identified in the four individual spectra that correspond to the rotational speeds of the five components in the analysis, (ii) the three formulations of the CS retain the relevant information from the individual spectra, thereby reducing the number of spectra required for monitoring and detecting rotating unbalances within a combine harvester, and, (iii) data noise reduction is observed in coherent and poly-coherent CS with respect to the non-coherent CS and the individual spectra. This study demonstrates that the rotating unbalances of various components within agricultural machines, can be detected with a reduced number of accelerometers located in non-optimal positions, and that it is feasible to simplify the monitoring with CS. Overall, the coherent CS may be the best composite spectra formulation in order to monitor and detect rotating unbalances in agricultural machines.

International audience; Applying elastic deformation can tune a material’s physical properties locally and reversibly. Spatially modulated lattice deformation can create a bandgap gradient, favoring photogenerated charge separation and collection in optoelectronic devices. These advantages are hindered by the maximum elastic strain that a material can withstand before breaking. Nanomaterials derived by exfoliating transition metal dichalcogenides (TMDs) are an ideal playground for elastic deformation, as they can sustain large elastic strains, up to a few percent. However, exfoliable TMDs with highly strain-tunable properties have proven challenging for researchers to identify. We investigated 1T-ZrS2 and 1T-ZrSe2, exfoliable semiconductors with large bandgaps. Under compressive deformation, both TMDs dramatically change their physical properties. 1T-ZrSe2 undergoes a reversible transformation into an exotic three-dimensional lattice, with a semiconductor-to-metal transition. In ZrS2, the irreversible transformation between two different layered structures is accompanied by a sudden 14% bandgap reduction. These results establish that Zr-based TMDs are an optimal strain-tunable platform for spatially textured bandgaps, with a strong potential for novel optoelectronic devices and light harvesting.

Unveiling and controlling the time evolution of the momentum and position of low energy excitations such as phonons, magnons, and electronic excitation is the key to attain coherently driven new functionalities of materials. Here we report the implementation of femtosecond time- and frequency-resolved multimode heterodyne detection and show that it allows for independent measurement of the time evolution of the position and momentum of the atoms in coherent vibrational states in α -quartz. The time dependence of the probe field quadratures reveals that their amplitude is maximally changed when the atoms have maximum momentum, while their phase encodes a different information and evolves proportionally to the instantaneous atomic positon. We stress that this methodology, providing the mean to map both momentum and position in one optical observable, may be of relevance for both quantum information technologies and time-domain studies on complex materials.

Non-Orthogonal Multiple Access (NOMA) technique and Carrierless Amplitude Phase (CAP) modulation have been used to demonstrate pay-as-you-grow coherent Passive Optical Networks (PON) and providing a 10 Gbps aggregate data rate.

In a time where computing resources and telecommunications requirements are exploding all around the world, the microelectronics industry has undertook over the past decade a major turnaround in their course to keep answering to the emerging technological needs of our societies. One of the ways undertaken is based on integrated photonics, which in particular requires the development of robust and energy efficient light sources at the nanoscale, with advanced optical functionalities. In this thesis, we propose a new concept of laser source emitting at 1550 nm, based on a system composed with two identical active optical nanocavities made of photonic crystal, coupled evanescently to a common waveguide. The coupling phase is then directly controlled by their relative distance. This system is fabricated by bonding a heterostructure of quantum wells in III-V semiconductor on an optical silicon circuit, followed by an electronic lithography and an ICP etching. In the context of an identical pumping, we thus demonstrated theoretically and experimentally the existence of two symmetrical and anti-symmetrical coupled modes, characterized by a splitting both in losses and in energy. The existence of a dark mode has also been predicted, which blocks the emission in the waveguide at particular coupling phases. More generally, the emission characteristics of this system allow us to assimilate it to a single effective cavity, whose the laser properties are modulated by the coupling phase. These can in particular be improved near the dark mode. The general exploration of this system finally opens the way to many other studies, based for instance on the variation of the pumping configuration and / or the coupling configuration of these cavities. In this context, other effects were observed, such as a directional emission in the waveguide, and the cancelling of this emission related to the presence of an exceptional point.; A l'heure de l'explosion des besoins en ressources de calcul et du volume des télécommunications dans le monde, l'industrie de la micro-électronique a engagé un changement de cap au cours de la dernière décennie, afin de pouvoir continuer à répondre aux besoins technologiques émergents de nos sociétés. L'une des voies entreprises repose sur la photonique intégrée, qui requiert notamment le développement de nanosources de lumière robustes et efficaces énergétiquement, et présentant des fonctionnalités optiques avancées. Nous proposons dans cette thèse un nouveau concept de nanosource laser émettant à 1550 nm, reposant sur un système de deux nanocavités optiques actives identiques en cristal photonique, couplées de façon évanescente à un même guide d'onde. La phase de couplage est alors directement contrôlée par leur distance relative. Ce système est fabriqué par l'adhésion d'une hétérostructure de puits quantiques en semiconducteur III-V sur une circuiterie optique en silicium, suivie d'une lithographie électronique et d'une gravure ICP. Dans le cadre d'un pompage identique, nous avons ainsi démontré théoriquement et expérimentalement l'existence de deux modes couplés symétrique et anti-symétrique, caractérisés par une séparation à la fois en pertes et en énergie. L'existence d'un mode sombre a également été prédite, et se manifeste par un blocage de l'émission pour certaines phases de couplage. Plus généralement, les caractéristiques de l'émission de ce système permettent de l'assimiler à une cavité unique effective, dont les propriétés laser sont modulées par la phase de couplage. Celles-ci peuvent notamment être améliorées à proximité du mode sombre. L'exploration générale de ce type de système ouvre finalement la voie à de nombreuses autres études, basées par exemple sur la variation de la configuration de pompage et/ou la configuration de couplage de ces cavités. Dans ce contexte, d'autres effets ont été observés, comme la directivité de l'émission dans le guide, et la manifestation d'un point exceptionnel induisant une extinction de l'émission.

In a time where computing resources and telecommunications requirements are exploding all around the world, the microelectronics industry has undertook over the past decade a major turnaround in their course to keep answering to the emerging technological needs of our societies. One of the ways undertaken is based on integrated photonics, which in particular requires the development of robust and energy efficient light sources at the nanoscale, with advanced optical functionalities. In this thesis, we propose a new concept of laser source emitting at 1550 nm, based on a system composed with two identical active optical nanocavities made of photonic crystal, coupled evanescently to a common waveguide. The coupling phase is then directly controlled by their relative distance. This system is fabricated by bonding a heterostructure of quantum wells in III-V semiconductor on an optical silicon circuit, followed by an electronic lithography and an ICP etching. In the context of an identical pumping, we thus demonstrated theoretically and experimentally the existence of two symmetrical and anti-symmetrical coupled modes, characterized by a splitting both in losses and in energy. The existence of a dark mode has also been predicted, which blocks the emission in the waveguide at particular coupling phases. More generally, the emission characteristics of this system allow us to assimilate it to a single effective cavity, whose the laser properties are modulated by the coupling phase. These can in particular be improved near the dark mode. The general exploration of this system finally opens the way to many other studies, based for instance on the variation of the pumping configuration and / or the coupling configuration of these cavities. In this context, other effects were observed, such as a directional emission in the waveguide, and the cancelling of this emission related to the presence of an exceptional point.; A l'heure de l'explosion des besoins en ressources de calcul et du volume des télécommunications dans le monde, l'industrie de la micro-électronique a engagé un changement de cap au cours de la dernière décennie, afin de pouvoir continuer à répondre aux besoins technologiques émergents de nos sociétés. L'une des voies entreprises repose sur la photonique intégrée, qui requiert notamment le développement de nanosources de lumière robustes et efficaces énergétiquement, et présentant des fonctionnalités optiques avancées. Nous proposons dans cette thèse un nouveau concept de nanosource laser émettant à 1550 nm, reposant sur un système de deux nanocavités optiques actives identiques en cristal photonique, couplées de façon évanescente à un même guide d'onde. La phase de couplage est alors directement contrôlée par leur distance relative. Ce système est fabriqué par l'adhésion d'une hétérostructure de puits quantiques en semiconducteur III-V sur une circuiterie optique en silicium, suivie d'une lithographie électronique et d'une gravure ICP. Dans le cadre d'un pompage identique, nous avons ainsi démontré théoriquement et expérimentalement l'existence de deux modes couplés symétrique et anti-symétrique, caractérisés par une séparation à la fois en pertes et en énergie. L'existence d'un mode sombre a également été prédite, et se manifeste par un blocage de l'émission pour certaines phases de couplage. Plus généralement, les caractéristiques de l'émission de ce système permettent de l'assimiler à une cavité unique effective, dont les propriétés laser sont modulées par la phase de couplage. Celles-ci peuvent notamment être améliorées à proximité du mode sombre. L'exploration générale de ce type de système ouvre finalement la voie à de nombreuses autres études, basées par exemple sur la variation de la configuration de pompage et/ou la configuration de couplage de ces cavités. Dans ce contexte, d'autres effets ont été observés, comme la directivité de l'émission dans le guide, et la manifestation d'un point exceptionnel induisant une extinction de l'émission.

We propose a novel implementation of a complex analog equalization filter for the compensation of frequency-dependent variations in coherent optical links. The analog compensation filter can be used in coherent-lite optical communication links where digital signal processing (DSP) is removed to limit the complexity and power consumption. In these links, the filter can compensate for electrical bandwidth limitations and distortion introduced by chromatic dispersion in the fiber. The complex filter is implemented by combining four distributed analog finite-impulse response (FIR) filters to obtain the necessary response. The filter delays are implemented using active delay cell structures to create a compact solution. The analog filter is implemented in a 55-nm BiCMOS technology and consumes 185-mW core power for five complex filter taps. Performance is evaluated using the S-parameter measurements, noise and linearity measurements, and real-time system experiments using 112-Gb/s 16-QAM-modulated signals.

We have recorded the diffraction patterns from individual xenon clusters irradiated with intense extreme ultraviolet pulses to investigate the influence of light-induced electronic changes on the scattering response. The clusters were irradiated with short wavelength pulses in the wavelength regime of different 4d inner-shell resonances of neutral and ionic xenon, resulting in distinctly different optical properties from areas in the clusters with lower or higher charge states. The data show the emergence of a transient structure with a spatial extension of tens of nanometers within the otherwise homogeneous sample. Simulations indicate that ionization and nanoplasma formation result in a light-induced outer shell in the cluster with a strongly altered refractive index. The presented resonant scattering approach enables imaging of ultrafast electron dynamics on their natural timescale., Structural Dynamics, 7 (3), ISSN:2329-7778

Part 1: Regular Papers; International audience; We review the most important WDM DCI system innovations. State-of-the-art coherent transmission has already exceeded 6 b/s/Hz, using subcarrier modulation. The adoption of software innovations in automation and programmability, that DCI pioneered in transport networks, has also simplified operations and enables the emergence of “open” transport architectures. Combining these advancements with emerging network analytics frameworks allows exciting innovations in network design and management optimization.

In an endeavour to better define the distinction between classical macroscopic and quantum microscopic regimes, the Leggett-Garg inequalities were established as a test of macroscopic-realistic theories, which are commonly thought to be a suitable class of descriptions for classical dynamics. The relationship between their violation and non-classicality is however not obvious. We show that classical states of light, which in the quantum optical sense are any convex sums of coherent states, may not satisfy the Leggett-Garg inequalities. After introducing a simple Mach-Zehnder setup and showing how to obtain a violation with a single photon using negative measurements, we focus on classical states of light, in particular those of low average photon number. We demonstrate how one can still perform negative measurements with an appropriate assignment of variables, and show that the inequalities are violable with coherent states. Finally, we abandon initial phase reference and demonstrate that the violation is still possible, in particular with thermal states of light, and we investigate the effect of intermediate dephasing., Comment: -Minor changes in abstract and introduction. -Added a comprehensive table with all possible cases for clarity. -Corrected result for thermal state. 10 pages, 5 figures

In condensed matter systems, coherent backscattering and quantum interference in the presence of time-reversal symmetry lead to well-known phenomena such as weak localization (WL) and universal conductance fluctuations (UCF). Here we use multi-pass Landau-Zener transitions at the avoided crossing of a highly-coherent superconducting qubit to emulate these phenomena. The average and standard deviation of the qubit transition rate exhibit a dip and peak when the driving waveform is time-reversal symmetric, analogous to WL and UCF, respectively. The higher coherence of this qubit enabled the realization of both effects, in contrast to earlier work arXiv:1204.6428, which successfully emulated UCF, but did not observe WL. This demonstration illustrates the use of non-adiabatic control to implement quantum emulation with superconducting qubits., 14 pages, 7 figures; two reference added; figure 4 changed; 2 more figures added in Suppl. Info

We make predictions for cross sections of $\rho$ and $\phi$ vector meson photoproduction in ultraperipheral Xe-Xe collisions at $\sqrt{s_{NN}}=5.44$ TeV. Analyzing the momentum transfer distribution of $\rho$ mesons in this process, we explore the feasibility of extracting the nuclear density of $^{129}$Xe, which is needed in searches for dark matter with Xenon-based detectors., Comment: 8 pages, 4 figures. Final published version