Diseño de un sistema presupuestario para la planificación y control de utilidades de la pequeña empresa industrial dedicada a la elaboración de ropa interior femenina en el área metropolítana de San Salvador. Caso ilustrativo.

La elaboración de este trabajo, consiste en el Diseño de un Sistema Presupuestario en la pequeña empresa industrial dedicada a la elaboración de ropa interior femenina ubicadas en el Area Metropolitana de San Salvador, que le permita al subsector ejecutar los presupuestos operativos y financieros desarrollados con el fin de lograr una adecuada planificación y control de utilidades. Para la elaboración del Sistema Presupuestario, se realizó un diagnóstico a las pequeñas empresas industriales que se dedican a la elaboración de prendas íntimas de vestir femenina con el objeto de hacer un análisis sobre la utilización de la técnica presupuestaria en las actividades y operaciones de la empresa. Asimismo, formular y desarrollar cada uno de los presupuestos a través de un caso ilustrativo que permita llevar a cabo la evaluación y control del Sistema presupuestario Para diagnóstico del subsector en estudio se utilizó en la investigación el método científico auxiliándose del método deductivo utilizando como técnica la entrevista hecha al presidente de la empresa y un cuestionario con preguntas abiertas y cerradas realizadas a las del subsector. Teniendo como resultado que la mayoría de las empresas de esta rama industrial no aplican dicha técnica presupuestaria por falta de conocimientos o recursos para su implementación. Por medio del caso ilustrativo se desarrolló la aplicación del Sistema presupuestario considerándose las generalidades de la empresa (objetivos, políticas, estrategias, filosofía y estructura organizativa); además de los supuestos básicos en los cuales se sustenta el Sistema. En la elaboración de los presupuestos, fue necesario apoyarse en el análisis de los datos históricos de la empresa, además de la experiencia del presidente de la organización. La aprobación del Sistema Presupuestario y la ejecución del mismo es responsabilidad del presidente de la empresa; para lo cual se presenta un plan de implementación del sistema, describiendo los recursos, costo y tiempo para la puesta en marcha del sistema. También es necesario llevar a cabo el control del Sistema Presupuestario, mediante el análisis de las variaciones y así poder implementar las medidas correctivas que lleven al cumplimiento de las metas y objetivos propuestos. Se recomienda a las pequeñas empresas industriales dedicadas a la elaboración de ropa interior femenina la aplicación del presente Sistema Presupuestario para una eficiente planificación y control de utilidades.

Evaluación de la exposición al ruido industrial en los trabajadores de una planta de asfalto, en la provincia del Azuay y propuesta de plan de control

El presente trabajo se realizó en una Planta de Hormigón Asfáltico, donde se realizó el estudio del ruido como factor de riesgo bajo las perspectivas de: Salud Ocupacional, Seguridad e Higiene Industrial. Este enfoque holístico, define la influencia que éste riesgo laboral ejerce sobre la pérdida de agudeza auditiva. Se estableció inicialmente el marco teórico y legal vigente sobre el ruido, posteriormente se describió la metodología de estudio, operatividad de variables, y la muestra a estudiar. Luego se procedió a la caracterización de la población y área estudiada, así como las actividades productivas. Dentro de la Higiene Industrial, se monitoreó la exposición del nivel de presión sonora, se realizó el comparativo con el nivel permisible (TWA 8 horas) establecido en el “Reglamento de Seguridad y Salud de los Trabajadores”, D.E. 2393. En términos de Seguridad Industrial, se analizó el equipo de protección personal EPP utilizado, y las variables determinantes. En el ámbito de Salud Ocupacional, se estudió: características personales de trabajadores, patologías relacionadas con sordera, y un cuestionario de exposición al ruido. Finalmente se determinó la existencia de sobreexposición a ruido laboral en la empresa objeto de estudio, mediante el estudio del estado de salud auditiva de los colaboradores se determinó la gran incidencia de personal sano y finalmente se determinó las medidas de control a implementarse enfatizadas a la realidad descubierta en el presente estudio, las que incluyen cambios en equipos y maquinaria, buenas prácticas de trabajo, planes de adiestramiento y capacitación en todo el personal entre otros.

Sistema de control interno COSO ERM en propiedad, planta y equipo de la mediana empresa industrial del área metropolítana de San Salvador.

El origen de esta investigación recae en la ausencia de control interno basado en la Administración de Riesgos Empresariales en las medianas empresas industriales dedicadas a la elaboración de productos metálicos. Este estudio fue realizado con el objetivo de elaborar una propuesta de sistema de control interno para la propiedad planta y equipo en el elemento de la maquinaría con el propósito de diseñar herramientas que mediante su aplicación controlen todos los movimientos y variaciones que presente la maquinaria para evitar los riesgos en el estudio de: las condiciones requeridas para la utilización de maquinaria en la producción y el establecimiento de políticas para dar de baja tomando en cuenta las consecuencias de los desechos de la maquinaría para el medio ambiente, mantenimiento oportuno en el uso de la maquinaría que garantice el óptimo funcionamiento de la misma a través de la asignación directa de la maquinaría al usuario responsable y delegación del personal técnico encargado y el establecimiento de mejoras en la utilización de la maquinaria específica para la obtención de logros en la producción Debido a que la maquinaría es de gran importancia ya que contribuye en el desarrollo de las actividades y en la generación de los ingresos de dichas empresas, es por esto que es preciso contar con un sistema de control interno que identifique, evalúe y de respuesta a los potenciales eventos relacionados, aportando actividades de control que cubran dichos eventos. A través de la metodología utilizada en la investigación se elaboraron instrumentos tales como cuestionarios por medio de los cuales se obtuvieron resultados que muestran la situación del control interno de la maquinaria en las medianas empresas industriales, determinando que la problemática que presentan dichos activos se deriva del poco control y atención que se le prestan a los mismos. Concluyendo que las medianas empresas industriales cuentan con controles internos pero que este no está siendo aprovechado para mejorar las actividades de las empresas tomando en cuenta la eficiencia, eficacia y economía en beneficio de la optimación de sus recursos. Recomendando la propuesta de un diseño que optimice el control interno de la propiedad planta y equipo en el elemento de la maquinaria de las medianas empresas industriales dedicadas a la elaboración de productos metálicos por medio de políticas, procedimientos e instrumentos basados en la Administración de Riesgos Empresariales establecidos en el mismo, que a su vez garanticen el logro de los objetivos trazados por la investigación

Sistema de control interno COSO ERM; área de producción para la mediana empresa industrial.

El control interno es de vital importancia para las entidades debido a que les permite mantenerse en la dirección de sus objetivos estratégicos, en la consecuencia de su misión y promoviendo la eficacia y eficiencia de sus operaciones Las medianas empresas industriales que se dedican a la transformación de cintas adhesivas deben establecer un sistema de control interno basado en el enfoque de Administración de Riesgos Empresariales aplicable al departamento de producción para que les permita garantizar el buen desarrollo de las actividades a lo largo del proceso de transformación. Por esta razón se presenta una propuesta de un sistema de control interno con enfoque de Administración de Riesgos Empresariales para el departamento de producción de las medianas empresas industriales que se dedican a la transformación de cintas adhesivas, estableciendo objetivos, riesgos, políticas, procedimientos e instrumentos de control interno a aspectos como la estructura organizativa del departamento de producción, compras, montaje, corte, acabado y almacenamiento. Para el desarrollo de la investigación se utilizó el enfoque Descriptivo-Deductivo con el cual se reunió conocimiento sobre el objeto en estudio y se indagó en las causas que dieron origen al fenómeno. Además se realizó una investigación de campo para recolectar información sobre la situación en que se encuentra el área de producción de las empresas industriales, haciendo uso de un cuestionario como instrumento de recolección de datos, procesando y tabulando la información de forma mecanizada y elaborando gráficos para facilitar la lectura de los resultados. Las medianas empresas industriales cuentan con líneas de autoridad y responsabilidades definidas para el área de producción, además el personal está facultado para desempeñarse de la mejor manera mediante capacitaciones y educación continua; sin embargo, existen actividades en las que pueden presentarse eventos potenciales q afectarían negativamente dicho departamento y para ello las empresas fortalecen los controles, mitigando los riesgos o en algunos casos optan por compartir el riesgo. Para comunicar información interna y externa que sea relevante para el buen desarrollo de las actividades dentro del área de producción, utilizan medios como capacitaciones y memorandos. Así mismo, se realizan supervisiones permanentes para monitorear las actividades que son desarrolladas diariamente en el departamento. Sin embargo, No todas las empresas han definido las mismas áreas para el departamento de producción, debido a que algunas empresas no han tomado en consideración el área de montaje, siendo esta tan importante como las otras. Además las actividades de control que aplican estas empresas, no logran mitigar, compartir, aceptar o evitar los riesgos evaluados desde el momento en que se adquiere la materia prima, pasando por las diferentes áreas, hasta que el artículo terminado ingresa en bodega, En conclusión las medianas empresas industriales dedicadas a la transformación de cintas adhesivas deberán dar énfasis a cada componente del sistema de control interno con enfoque de Administración de Riesgos Empresariales, los cuales deberán ser adaptados a los cambios de circunstancias, como un proceso continuo y dinámico necesario para ayudar a la consecución de los objetivos.

Impacts of trace element pollution on sewage sludge and soil-plant systems: developing remediation techniques and assessing plant uptake prevention measures

Trace Elements (TEs) pollution is a significant environmental concern due to its toxic effects on human and ecosystem health and its potential to bioaccumulate in the food chain and to threaten species survival, leading to a decline in biodiversity. Urban areas, industrial and mining activities, agricultural practices, all contribute to the release of TEs into the environment posing a significant risk to human health and ecosystems. Several techniques have been developed to control TEs into the environment. This work presents the findings of three-year PhD program that focused on research on TEs pollution. The study discusses three fundamental aspects related to this topic from the perspective of sustainable development, environmental and human health. (1) High levels of TEs contamination prevent the use of sewage sludge (SS) as a fertilizer in agriculture, despite its potential as a soil amendment. Developing effective techniques to manage TEs contamination in SS is critical to ensure its safe use in agriculture and promote resource efficiency through sludge reuse. Another purpose of the study was to evaluate different strategies to limit the TEs uptake by horticultural crops (specifically, Cucumis Melo L.). This study addressed the effect of seasonality, Trichoderma inoculation and clinoptilolite application on chromium (Cr), copper (Cu) and lead (Pb) content of early- and late-ripening cultivars of Cucumis Melo L.. Finally, the accumulation of copper and the effect of its bioavailable fraction on bacterial and fungal communities in the rhizosphere soil of two vineyards, featuring two different varieties of Vitis vinifera grown for varying lengths of time, were evaluated.

Modeling and Model Predictive Control of an Industrial Hydraulic System

This thesis aims to illustrate the construction of a mathematical model of a hydraulic system, oriented to the design of a model predictive control (MPC) algorithm. The modeling procedure starts with the basic formulation of a piston-servovalve system. The latter is a complex non linear system with some unknown and not measurable effects that constitute a challenging problem for the modeling procedure. The first level of approximation for system parameters is obtained basing on datasheet informations, provided workbench tests and other data from the company. Then, to validate and refine the model, open-loop simulations have been made for data matching with the characteristics obtained from real acquisitions. The final developed set of ODEs captures all the main peculiarities of the system despite some characteristics due to highly varying and unknown hydraulic effects, like the unmodeled resistive elements of the pipes. After an accurate analysis, since the model presents many internal complexities, a simplified version is presented. The latter is used to linearize and discretize correctly the non linear model. Basing on that, a MPC algorithm for reference tracking with linear constraints is implemented. The results obtained show the potential of MPC in this kind of industrial applications, thus a high quality tracking performances while satisfying state and input constraints. The increased robustness and flexibility are evident with respect to the standard control techniques, such as PID controllers, adopted for these systems. The simulations for model validation and the controlled system have been carried out in a Python code environment.

Integration of ROS for the control of industrial robotic systems in a proprietary environment

The paper deals with the integration of ROS, in the proprietary environment of the Marchesini Group company, for the control of industrial robotic systems. The basic tools of this open-source software are deeply studied to model a full proprietary Pick and Place manipulator inside it, and to develop custom ROS nodes to calculate trajectories; speaking of which, the URDF format is the standard to represent robots in ROS and the motion planning framework MoveIt offers user-friendly high-level methods. The communication between ROS and the Marchesini control architecture is established using the OPC UA standard; the tasks computed are transmitted offline to the PLC, supervisor controller of the physical robot, because the performances of the protocol don’t allow any kind of active control by ROS. Once the data are completely stored at the Marchesini side, the industrial PC makes the real robot execute a trajectory computed by MoveIt, so that it replicates the behaviour of the simulated manipulator in Rviz. Multiple experiments are performed to evaluate in detail the potential of ROS in the planning of movements for the company proprietary robots. The project ends with a small study regarding the use of ROS as a simulation platform. First, it is necessary to understand how a robotic application of the company can be reproduced in the Gazebo real world simulator. Then, a ROS node extracts information and examines the simulated robot behaviour, through the subscription to specific topics.

Industrial Demilitarized Zone and Zero Trust cybersecurity models for Industrial Control Systems

Today more than ever, with the recent war in Ukraine and the increasing number of attacks that affect systems of nations and companies every day, the world realizes that cybersecurity can no longer be considered just as a “cost”. It must become a pillar for our infrastructures that involve the security of our nations and the safety of people. Critical infrastructure, like energy, financial services, and healthcare, have become targets of many cyberattacks from several criminal groups, with an increasing number of resources and competencies, putting at risk the security and safety of companies and entire nations. This thesis aims to investigate the state-of-the-art regarding the best practice for securing Industrial control systems. We study the differences between two security frameworks. The first is Industrial Demilitarized Zone (I-DMZ), a perimeter-based security solution. The second one is the Zero Trust Architecture (ZTA) which removes the concept of perimeter to offer an entirely new approach to cybersecurity based on the slogan ‘Never Trust, always verify’. Starting from this premise, the Zero Trust model embeds strict Authentication, Authorization, and monitoring controls for any access to any resource. We have defined two architectures according to the State-of-the-art and the cybersecurity experts’ guidelines to compare I-DMZ, and Zero Trust approaches to ICS security. The goal is to demonstrate how a Zero Trust approach dramatically reduces the possibility of an attacker penetrating the network or moving laterally to compromise the entire infrastructure. A third architecture has been defined based on Cloud and fog/edge computing technology. It shows how Cloud solutions can improve the security and reliability of infrastructure and production processes that can benefit from a range of new functionalities, that the Cloud could offer as-a-Service.We have implemented and tested our Zero Trust solution and its ability to block intrusion or attempted attacks.

Axis control optimization: autotuning techniques and frequency response analysis of industrial mechatronic systems

In the field of industrial automation, there is an increasing need to use optimal control systems that have low tracking errors and low power and energy consumption. The motors we are dealing with are mainly Permanent Magnet Synchronous Motors (PMSMs), controlled by 3 different types of controllers: a position controller, a speed controller, and a current controller. In this thesis, therefore, we are going to act on the gains of the first two controllers by going to find, through the TwinCAT 3 software, what might be the best set of parameters. To do this, starting with the default parameters recommended by TwinCAT, two main methods were used and then compared: the method of Ziegler and Nichols, which is a tabular method, and advanced tuning, an auto-tuning software method of TwinCAT. Therefore, in order to analyse which set of parameters was the best,several experiments were performed for each case, using the Motion Control Function Blocks. Moreover, some machines, such as large robotic arms, have vibration problems. To analyse them in detail, it was necessary to use the Bode Plot tool, which, through Bode plots, highlights in which frequencies there are resonance and anti-resonance peaks. This tool also makes it easier to figure out which and where to apply filters to improve control.

Urban air pollution and chronic obstructive pulmonary disease-related emergency department visits

Background: Patients with chronic obstructive pulmonary disease (COPD) can have recurrent disease exacerbations triggered by several factors, including air pollution. Visits to the emergency respiratory department can be a direct result of short-term exposure to air pollution. The aim of this study was to investigate the relationship between the daily number of COPD emergency department visits and the daily environmental air concentrations of PM(10), SO(2), NO(2), CO and O(3) in the City of Sao Paulo, Brazil. Methods: The sample data were collected between 2001 and 2003 and are categorised by gender and age. Generalised linear Poisson regression models were adopted to control for both short-and long-term seasonal changes as well as for temperature and relative humidity. The non-linear dependencies were controlled using a natural cubic spline function. Third-degree polynomial distributed lag models were adopted to estimate both lag structures and the cumulative effects of air pollutants. Results: PM(10) and SO(2) readings showed both acute and lagged effects on COPD emergency department visits. Interquartile range increases in their concentration (28.3 mg/m(3) and 7.8 mg/m(3), respectively) were associated with a cumulative 6-day increase of 19% and 16% in COPD admissions, respectively. An effect on women was observed at lag 0, and among the elderly the lag period was noted to be longer. Increases in CO concentration showed impacts in the female and elderly groups. NO(2) and O(3) presented mild effects on the elderly and in women, respectively. Conclusion: These results indicate that air pollution affects health in a gender-and age-specific manner and should be considered a relevant risk factor that exacerbates COPD in urban environments.

Impact of Manaus City on the Amazon Green Ocean atmosphere: ozone production, precursor sensitivity and aerosol load

As a contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia - Cooperative LBA Airborne Regional Experiment (LBA-CLAIRE-2001) field campaign in the heart of the Amazon Basin, we analyzed the temporal and spatial dynamics of the urban plume of Manaus City during the wet-to-dry season transition period in July 2001. During the flights, we performed vertical stacks of crosswind transects in the urban outflow downwind of Manaus City, measuring a comprehensive set of trace constituents including O(3), NO, NO(2), CO, VOC, CO(2), and H(2)O. Aerosol loads were characterized by concentrations of total aerosol number (CN) and cloud condensation nuclei (CCN), and by light scattering properties. Measurements over pristine rainforest areas during the campaign showed low levels of pollution from biomass burning or industrial emissions, representative of wet season background conditions. The urban plume of Manaus City was found to be joined by plumes from power plants south of the city, all showing evidence of very strong photochemical ozone formation. One episode is discussed in detail, where a threefold increase in ozone mixing ratios within the atmospheric boundary layer occurred within a 100 km travel distance downwind of Manaus. Observation-based estimates of the ozone production rates in the plume reached 15 ppb h(-1). Within the plume core, aerosol concentrations were strongly enhanced, with Delta CN/Delta CO ratios about one order of magnitude higher than observed in Amazon biomass burning plumes. Delta CN/Delta CO ratios tended to decrease with increasing transport time, indicative of a significant reduction in particle number by coagulation, and without substantial new particle nucleation occurring within the time/space observed. While in the background atmosphere a large fraction of the total particle number served as CCN (about 60-80% at 0.6% supersaturation), the CCN/CN ratios within the plume indicated that only a small fraction (16 +/- 12 %) of the plume particles were CCN. The fresh plume aerosols showed relatively weak light scattering efficiency. The CO-normalized CCN concentrations and light scattering coefficients increased with plume age in most cases, suggesting particle growth by condensation of soluble organic or inorganic species. We used a Single Column Chemistry and Transport Model (SCM) to infer the urban pollution emission fluxes of Manaus City, implying observed mixing ratios of CO, NO(x) and VOC. The model can reproduce the temporal/spatial distribution of ozone enhancements in the Manaus plume, both with and without accounting for the distinct (high NO(x)) contribution by the power plants; this way examining the sensitivity of ozone production to changes in the emission rates of NO(x). The VOC reactivity in the Manaus region was dominated by a high burden of biogenic isoprene from the background rainforest atmosphere, and therefore NO(x) control is assumed to be the most effective ozone abatement strategy. Both observations and models show that the agglomeration of NO(x) emission sources, like power plants, in a well-arranged area can decrease the ozone production efficiency in the near field of the urban populated cores. But on the other hand remote areas downwind of the city then bear the brunt, being exposed to increased ozone production and N-deposition. The simulated maximum stomatal ozone uptake fluxes were 4 nmol m(-2) s(-1) close to Manaus, and decreased only to about 2 nmol m(-2) s(-1) within a travel distance >1500 km downwind from Manaus, clearly exceeding the critical threshold level for broadleaf trees. Likewise, the simulated N deposition close to Manaus was similar to 70 kg N ha(-1) a(-1) decreasing only to about 30 kg N ha(-1) a(-1) after three days of simulation.

Embedded DSP-Based Compact Fuzzy System and Its Application for Induction-Motor V/f Speed Control

This paper presents a compact embedded fuzzy system for three-phase induction-motor scalar speed control. The control strategy consists in keeping constant the voltage-frequency ratio of the induction-motor supply source. A fuzzy-control system is built on a digital signal processor, which uses speed error and speed-error variation to change both the fundamental voltage amplitude and frequency of a sinusoidal pulsewidth modulation inverter. An alternative optimized method for embedded fuzzy-system design is also proposed. The controller performance, in relation to reference and load-torque variations, is evaluated by experimental results. A comparative analysis with conventional proportional-integral controller is also achieved.

Control system design for flexible rotors supported by actively lubricated bearings

This article presents a methodology for calculating the gains of an output feedback controller for active vibration control of flexible rotors. The methodology is based on modal reduction. The proportional and derivative gains are obtained by adjusting the first two damping factors of the system and keeping the lengths of the two eigenvalues constant in the real-imaginary plane. The methodology is applied to an industrial gas compressor supported by active tilting-pad journal bearings. The unbalance response functions and mode shapes of the flexible rotor with and without active control are presented, showing significative improvement in damping reserve with the control. The importance of sensor location is emphasized, on the basis of the energy necessary to operate the active system over the entire frequency range studied. The best results are obtained by a decentralized controller, observing displacement and velocity of the shaft at the bearing positions.

Remote control of CNC machines using the CyberOPC communication system over public networks

During the last few years, the evolution of fieldbus and computers networks allowed the integration of different communication systems involving both production single cells and production cells, as well as other systems for business intelligence, supervision and control. Several well-adopted communication technologies exist today for public and non-public networks. Since most of the industrial applications are time-critical, the requirements of communication systems for remote control differ from common applications for computer networks accessing the Internet, such as Web, e-mail and file transfer. The solution proposed and outlined in this work is called CyberOPC. It includes the study and the implementation of a new open communication system for remote control of industrial CNC machines, making the transmission delay for time-critical control data shorter than other OPC-based solutions, and fulfilling cyber security requirements.

Treatment of industrial effluents of recalcitrant nature using ozone, hydrogen peroxide and ultraviolet radiation

Currently diverse industries have high pollution potential because their productive processes generate great volumes of refractory effluents. These effluents are problematic, mainly due to the presence of recalcitrant compounds that are detrimental in wastewater treatment plants using biological systems in their processes. In general, biological treatments do not remove refractory elements. Also, in most cases these compounds can inhibit the yield or are toxic for biota responsible to remove the polluting agents. The Advanced Oxidative Processes (AOPs) represent a technological alternative with a great potential for treatment of no biodegradable effluents. In this paper a review of the use of advanced oxidatives processes: Ozone (O(3)), peroxide of hydrogen (H(2)O(2)) and ultraviolet radiation (UV) is presented applied to the treatment of recalcitrant effluents.