Poder tributario : aplicación de la prohibición de decretar impuestos en el ordenamiento jurídico colombiano por parte del Ejecutivo

73 páginasThis research work intends to study the extraordinary faculties of the executive power to legislate in the Colombian legal system, furthermore, it performs a meticulous study of the article 150 of the political constitution that establishes the prohibition for the executive power to create taxes since it could implicate a violation of the principie of no taxation without representation established in the contemporary's political constitutions. This research it's divided in two parts, first, it will be studied the historical and conceptual dimensions of the Colombian state power to tax, and second, a detailed study of the procedure to create a decree law, the tax implications and the different acts the executive power use to create, modify or replace taxes will be done.El presente trabajo de investigación pretende abordar las facultades extraordinarias para legislar el poder ejecutivo en el ordenamiento jurídico colombiano, así como realizar un estudio detallado de la prohibición de decretar impuestos al ejecutivo consagrado en el artículo 150 de la Constitución en cuanto podría suponer una vulneración al principio de no impuestos sin representación consagrado en las constituciones contemporáneas. Este trabajo estará divido en dos partes, por un lado, se estudiará el ámbito histórico y conceptual del poder tributario en el Estado colombiano, y por otro, se analizará de forma detallada el procedimiento de creación de los decretos ley, las implicaciones tributarias y los diferentes actos a través de los cuales el ejecutivo crea, sustituye o modifica impuestos.Abogado(a)Pregrad

VCO-based ADC with a simplified DAC for non-linearity correction

The performance of open-loop ADCs implemented with VCOs is limited by VCO non-linearity and first-order noise shaping. The resolution limitation imposed by first-order noise shaping can be compensated by a ring oscillator VCO with many output phases. Linearity can also be improved by using a feedback loop around the VCO closed with a DAC. However, a long ring oscillator may require a DAC with a prohibitive number of bits if feedback is used to compensate distortion. This Letter proposes an ADC architecture based on the Leslie-Singh Sigma-Delta (Σ∆) modulator that allows to implement a distortion correction loop around a VCO with a simplified DAC of few levels, yet keeping a large number of output quantisation levels to maintain resolution. The Letter discusses the system-level architecture and shows an implementation circuit example to verify the effective correction of distortion.This work has been supported by the CICYT project TEC2014-56879-R, Spain

A VCO-based CMOS readout circuit for capacitive MEMS microphones

Microelectromechanical systems (MEMS) microphone sensors have significantly improved in the past years, while the readout electronic is mainly implemented using switched-capacitor technology. The development of new battery powered 'always-on” applications increasingly requires a low power consumption. In this paper, we show a new readout circuit approach which is based on a mostly digital Sigma Delta (SigmaDelta) analog-to-digital converter (ADC). The operating principle of the readout circuit consists of coupling the MEMS sensor to an impedance converter that modulates the frequency of a stacked-ring oscillator—a new voltage-controlled oscillator (VCO) circuit featuring a good trade-off between phase noise and power consumption. The frequency coded signal is then sampled and converted into a noise-shaped digital sequence by a time-to-digital converter (TDC). A time-efficient design methodology has been used to optimize the sensitivity of the oscillator combined with the phase noise induced by 1/𝑓 and thermal noise. The circuit has been prototyped in a 130 nm CMOS process and directly bonded to a standard MEMS microphone. The proposed VCO-based analog-to-digital converter (VCO-ADC) has been characterized electrically and acoustically. The peak signal-to-noise and distortion ratio (SNDR) obtained from measurements is 77.9 dB-A and the dynamic range (DR) is 100 dB-A. The current consumption is 750 muA at 1.8 V and the effective area is 0.12 mm2. This new readout circuit may represent an enabling advance for low-cost digital MEMS microphones.This research was funded by project TEC2017-82653-R of CICYT, Spain

Sistema de información para la gestión de proyectos de grado en la Corporación Universitaria Minuto de Dios Centro Regional Soacha "UNIPROYECTOS"

Se busca crear un sistema de información transaccional, el cual permita conocer al detalle cada avance de un proyecto de grado mediante casos generados, asesorías brindadas, estimación de tiempos, actualizaciones de estado y notificaciones personales por medio de correo a estudiantes, docentes y directivos, usando para ello la metodología RAD (Rapid Application Development – Desarrollo Rápido de Aplicaciones), que permite un rápido desarrollo y entrega de una alta calidad en este proyecto de bajo coste de inversión. La implementación de este proyecto en la Universidad facilitaría la obtención de información con respecto a los proyectos de grado que se desarrollan y sería muy útil para los directivos al momento de hacer seguimiento los proyectos

Low Power Phase-Encoded MAC Accelerator for Smart Sensors with VCO-based ADCs

Proceeding of: 2020 IEEE 63rd International Midwest Symposium on Circuits and Systems (MWSCAS): August 9-12, 2020, Springfield, MA, USA: on-line proceedings.A new phase-encoded MAC cell is proposed for low power smart sensing applications. If digitization of the raw data is made through voltage-controlled-oscillators based analog-to-digital converters (VCO-based ADCs), we may take the unsampled frequency-encoded output signal and connect it to the first layer of a neural network. Then that layer could be implemented with phase-encoded MAC accelerators, leading to an energy-efficient solution. The MAC cell does not only make the accumulation/subtraction and multiplication operation, but also the non-linear function which supposes a great advantage with respect to other equivalent cells. A circuit example is proposed in a 65-nm CMOS process and transient simulations prove the feasibility of the approach.Publicad

Optical absorption coefficient of different tortillas by photoacoustic spectroscopy

The color of the tortilla is one of the properties that determine the purchasing decision and acceptance for the consumer. This sensory attribute is altered, when making tortillas with elements to improve digestion and nutrition. Therefore, the objective of this investigation was to determine some information about the color in different types of tortilla found in the commercial market in gEcatepec, Edo de Mexicoh. Optical absorption coefficients (β) were obtained from them by photoacoustic spectroscopy technique of closed cell, one of the photothermal techniques. Optical absorption spectra of each tortilla were recorded by means of photoacoustic spectroscopy (PAS) in the 350 to 700 nm range. Thirteen types of tortillas were evaluated, the experimental unit comprised three tortillas, among which one tortilla was selected at random for each repetition. The β values were determined from the photoacoustic (PA) signals amplitude and using the Rosencwaig and Gersho model. Data was subjected to variance analysis (ANOVA) using the SAS GLM procedures. The ANOVA revealed significant (p . 0.05) differences among tortillas. The results were analyzed statistically and correlated with preferences of a group of people in the same area, when a sensory test was applied; the test evaluated the color attribute by using the hedonic scale.Key words: Tortilla, color, optical absorption coefficient, photoacoustic spectroscopy, sensory evaluation

MicroRNAs Associated with Secondary Metabolites Production

MicroRNAs (miRNAs) are noncoding RNAs that play an important role in the regulation of the genetic expression in animals and plants by targeting mRNAs for cleavage or translational repression. Several miRNAs regulate the plant development, the metabolism, and the responses to biotic and abiotic stresses. Characterization of an miRNA has helped to show its role in fine tuning the mechanisms of posttranscriptional gene regulation. Although there is a lot of information related to miRNA regulation of some processes, the role of miRNA involved in the regulation of biosynthesis of secondary plant product is still poorly understood. In this chapter, we summarize the identification and characterization of miRNAs that participate in the regulation of the biosynthesis of secondary metabolites in plants and their use in the strategies to manipulate a controlled manipulation