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This study analyzes the importance of developing a high-current system, with a capacity of up to 65 kA and 1 kV, for testing low-voltage electrical equipment in the Colombian electricity sector. The development of highcurrent systems at the national and international levels are reviewed, revealing the relevance of the project for the Colombian electricity sector. The proposed high-current system is defined by the following components: toroidal transformers (high-current source), a metrological system, a control system, and a protection system. Implementing this system would strengthen the research and experimental design of equipment such as lowvoltage switchgear, metal-enclosed switchgear, and transformers. In conclusion, building a high-current testing system by IGT S.A.S., with support from Universidad del Valle, significantly increases the scientific and technological capabilities of the Colombian electricity sector. [ABSTRACT FROM AUTHOR]

This work describes the way in which serious games are used in virtual reality for fine motor rehabilitation in an upper limb, as a possible rehabilitation tool for patients who have suffered a cerebrovascular accident. A glove equipped with flexible sensors was built, which allows to move a virtual hand on the computer. A virtual environment was implemented in Unity 3D where the patient is registered, and where his rehabilitation is stimulated through four games under the supervision of the therapist. The four implemented games allow developing the spherical, cylindrical and pincer grasp, as well as the global mobility of the fingers. The system was tested with 12 users. It is expected that the project developed can become an additional tool for the therapist to schedule various rehabilitation sessions for the patient. [ABSTRACT FROM AUTHOR]

In Colombia, there is currently no regulation that specifies the metrics that must be taken into account in terms of the requirements of the control systems of a microgrid (MGCS Microgrid Control System). Starting from the previous problem, it was necessary to have a review article, which will present in a synthesized way the protocols and tests that must be carried out in the control systems, before their commissioning. The results show the basic functions that a control system must have. The functions are, dispatch and transition, these central functions are the basis for the correct operation of the MGCS and for this reason their respective tests are presented. Section 2 will address these functions and will present a series of tables describing the requirements, as well as their characteristics and metrics. Section 3 shows the tests, sets out the scenarios where they should be tested and the variables that should be measured. In section 4 the importance of communications within the MGCS is exposed, since the synergy of all assets, such as protections, distributed generation (DG distributed generation) and loads, depends on an excellent communication, for which a variety will be mentioned. of technologies to achieve this interaction between all these elements. It is intended that this reflection article presented serves in a practical way in terms of the application of the standards that served as the basis. This will allow future engineers who wish to implement this type of technology to have at hand a clear summary regarding the requirements of the control system, since they are the fundamental basis of the microgrid (MR). [ABSTRACT FROM AUTHOR]

The present study examines the vulnerability and management of distributed energy resources for the qualification of a power system’s resilience against a deliberate attack. The system operator must minimize the impact of the attack by dispatching centralized generation and by using distributed energy resources (DER). Initially, the vulnerability analysis problem is approached by means of a genetic algorithm (GA), in which a disruptive agent aims at maximizing the damage to the system by attacking a set of lines and generators. DER management is assessed by using distributed generation (DG) and demand response (DR) as key elements to mitigate post-attack effects. The tests performed on the IEEE-RTS 24 bus test system show that the best resilience indicator is obtained with the joint operation of DG and DR. It is concluded that it is possible to increase resilience by strategically using the DER left available to the network’s operator. [ABSTRACT FROM AUTHOR]

The main objective of this study is to propose a new model and solution method for multi-period optimal reactive power dispatch. This is an inherently non-convex and nonlinear problem. Therefore, it is solved by applying a mean-variance mapping optimization metaheuristic. The proposed model allows incorporating intertemporal constraints. One advantage of the model is the design of its objective function that allows to simultaneously assess the feasibility and optimality of a solution. The model and solution approach is validated by using the IEEE 30-bus test system. The results show and allow concluding that the proposed model guarantees an adequate reactive power management that minimizes power losses by keeping transformer taps and capacitor bank movements within limits to maximize lifetime. [ABSTRACT FROM AUTHOR]

The NFV pre-deployment test platforms allow service providers to evaluate and characterize the performance of virtual network functions that they wish to acquire before opting for large NFV deployments, which enables the reduction of CAPEX and OPEX and in the time of deployment and validation of new services. There are currently proprietary and open source test platforms and business models that propose test solutions for NFV. Selecting open source pre-deployment test platforms appropriate to the needs of the service provider is the objective of the present investigation. Based on this, a selection of test platforms suitable for the proposed objective, grouped in systems under test, is proposed. This selection is applied to two cases of study starting from a common virtual infrastructure manager for the deployment of the test platforms. [ABSTRACT FROM AUTHOR]

What is the role of communication media in the industry and fashion culture in a country like Ecuador? It is necessary to start by understanding the fashion system and how it has been disseminated through its own languages and symbolisms, in order to understand the impact it has generated on local cultural codes. Communication has played a special role in food imagination, consumption and business that does not respect local meanings. In fact, you have never played a leading role in the visibility of those who are "ajenos", completing the concept of the national and how we define local fashion. Fashion communication formats are in a disruptive moment that puts a traditional system to the test while making it increasingly necessary to see fashion beyond brands, media and characters. The need to analyze communication formats and their contents in the cultural impact of the development of this industry, which has had environmental, economic and social interference in Ecuador, is not negotiable. [ABSTRACT FROM AUTHOR]

The objective of this research study is to provide an optimization tool for power system restoration after a largescale blackout. A mixed integer linear programming model is proposed to approach the restoration problem of power systems. To validate the proposed model, two testing systems are used: 1) a four generator didactic system and 2) the IEEE-39 RTS system. The results in both systems show the effectiveness and the robustness of the proposed model. In particular, the results obtained using the IEEE-39 RTS testing system show that the model can be implemented in real applications. Given the nature of the model, it can be concluded that the model guarantees the achievement of a global optimal solution, which indicates the sequence of generation units that must be set online, minimizing restoration time. [ABSTRACT FROM AUTHOR]

Due the worldwide growing food demand, efforts toward to resource optimization in crops, are required. With this purpose, the use of technology is a big chance to deal these challenges, with the aim of automatizing agricultural processes. Within the tasks in agriculture, by example wedding, supply fertilizers or fungicides, the mobile robots have a potential use to assist these tasks. Then, from this work, velocity control of a differential mobile platform is developed, in order to perform precision agriculture tasks. Specifically, mathematical modelling, design of state feedback control and the integration to the robot hardware, through Hardware in the loop (HIL) simulations, validation test are performed by using ROS environment, embedded devices and mathematical simulations, at previous stage to real test. Showing a full integration of the proposed system to test and prove mobile robots. [ABSTRACT FROM AUTHOR]

This paper presents two techniques for identifying topological scenarios of transmission networks for security enhancement in degraded network conditions. The implemented techniques are Simulated Annealing and Iterated Local Search. The objective of the topological modifications is the reduction of the number of violated constraints under N-1 contingencies. The proposed search techniques make topologic explorations through state changes in sub-station switches. These explorations are used to find reconfigurations of the electric power system which guaranty a higher level of security in face of N-1 contingencies when compared with the case when the topology is not changed. Security conditions consider an AC model and a bay-switch model to the assessment of contingencies, which allows the evaluation of real conditions of failure release in the power system. Results are presented with the IEEE 118 bus test system that demonstrates the effectiveness and applicability of the proposed techniques. [ABSTRACT FROM AUTHOR]

This paper presents an algorithm oriented to improve the security conditions of electric power systems. The proposed algorithm performs a semi-exhaustive search of the possible configuration of the system substation with the objective of minimizing overloads presented in single contingencies (N-1 criterion). Topological modifications are made by changing the state of switches in substations. Results are presented for the IEEE 118 bus test system showing the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

It is presented a system to detect pulses by using a piezoelectric sensor. Basic proofs were made using commercial piezoelectric ceramics and others obtained in our laboratory. Very good results were obtained. The system allows detecting the pulses, which are generated by the piezoelectric material when a mechanical stress is applied. A data acquisition program was developed for the signal records, analysis and comparison of the results. [ABSTRACT FROM AUTHOR]

This paper presents a lineal optimization model to solve the hydrothermal coordination problem. The main contribution of this work is the inclusion of the network constraints to the hydrothermal coordination problem and its solution using an interior point method. The proposed model allows working with a system that can be completely hydraulic, thermal or mixed. Results are presented on the IEEE 14 bus test system. [ABSTRACT FROM AUTHOR]

Fault location in power distribution systems is an important aspect of power quality, in particular, in relation to power supply continuity. Currently, there are two clearly defined methods commonly used to locate faults, those which are based on the power system model and those which are based on knowledge. Fault location methods based on knowledge use information obtained from signals of voltage and current measured during fault situations, and normally require a considerable amount of fault registers to have a successful performance. This paper presents the modeling of a power distribution system and its protective relaying, settled in a fuse saving scheme. Using the described power system, it is possible to obtain a fault database by means of an event automatic generation using the Alternative Transient Program (ATP) and Matlab. The fault database can be used to perform different types of system analysis and in this specific case to solve the problem of fault location in power distribution systems using knowledge based methods. As a result, a data base which contains 930 different fault simulations on a 25 node test system was obtained. [ABSTRACT FROM AUTHOR]

The availability of biological laboratory reference materials, calibrated against international reference standards, is very useful to check the good performance of control techniques employed to measure the potency of biologic reagents. The aim of this work was the obtention of laboratory reference materials of measles virus for its use as a biological control in microtiter plate test. Different stocks of Edmonston Zagreb strains of measles virus were titrated 8 times to validate our test system and choose one of them as laboratory reference material. The selected virus stock was titrated 34 times, there were no variations in infective titer (3,6 log10) higher than ± 0,5 log10 between assays. It was also calibrated against the international reference standards (IRS) Edmonston ATCC 821638. To demonstrate the stability of the infective titer of the IRS, it was calibrated again at 3, and 6 months and 1 year. Reproducibility was observed in the results, suggesting that our product can be used as Laboratory Standard in our working conditions. [ABSTRACT FROM AUTHOR]