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This paper addresses the optimal placement and sizing of Modular Static Synchronous Series Compensators (M-SSSCs) to enhance power system performance. The proposed methodology optimizes four key objectives: reducing transmission line loadability, minimizing power losses, mitigating voltage deviations, and enhancing voltage stability using the L-index. The methodology is validated on two systems: the IEEE 14-bus test network and a sub-area of the Colombian power grid, characterized by aging infrastructure and operational challenges. The optimization process employs three metaheuristic algorithms—Genetic Algorithm (GA), Particle Swarm Optimization (PSO), and Teaching–Learning-Based Optimization (TLBO)—to identify optimal configurations. System performance is analyzed under both normal operating conditions and contingency scenarios (N − 1). The results demonstrate that M-SSSC deployment significantly reduces congestion, enhances voltage stability, and improves overall system efficiency. Furthermore, this work highlights the practical application of M-SSSC in modernizing real-world grids, aligning with sustainable energy transition goals. This study identifies the optimal M-SSSC configurations and placement alternatives for the analyzed systems. Specifically, for the Colombian sub-area, the most suitable solutions involve installing M-SSSC devices in capacitive mode on the Termocol–Guajira and Santa Marta–Guajira 220 kV transmission lines. [ABSTRACT FROM AUTHOR]

Copyright of UCV Hacer is the property of UCV Hacer and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, social assistive robots have gained significant acceptance in healthcare settings, particularly for tasks such as patient care and monitoring. This paper offers a comprehensive overview of the expressive humanoid robot, Qhali, with a focus on its industrial design, essential components, and validation in a controlled environment. The industrial design phase encompasses research, ideation, design, manufacturing, and implementation. Subsequently, the mechatronic system is detailed, covering sensing, actuation, control, energy, and software interface. Qhali's capabilities include autonomous execution of routines for mental health promotion and psychological testing. The software platform enables therapist-directed interventions, allowing the robot to convey emotional gestures through joint and head movements and simulate various facial expressions for more engaging interactions. Finally, with the robot fully operational, an initial behavioral experiment was conducted to validate Qhali's capability to deliver telepsychological interventions. The findings from this preliminary study indicate that participants reported enhancements in their emotional well-being, along with positive outcomes in their perception of the psychological intervention conducted with the humanoid robot. [ABSTRACT FROM AUTHOR]

This document is an editorial for a special issue of the journal Information Systems Frontiers on social robotics. It discusses the concept of social robots and their various applications, such as companion robots for older adults and therapeutic robots for children with autism. The document explores the features and capabilities of social robots, including their humanoid form and artificial intelligence capabilities. It emphasizes the need for further research on the ethical, social, and legal implications of social robots, as well as trust, user acceptance, and design considerations. The document provides a summary of various articles related to social robots and their implications in different fields, covering topics such as the psychological contract between humans and robots, the impact of AI on service robots, and security and privacy concerns. The authors of the articles come from different academic backgrounds and institutions, providing diverse perspectives on the subject. The document concludes by highlighting the importance of addressing open questions and conducting further research to ensure the ethical and responsible implementation of social robots. [Extracted from the article]

Under-frequency load shedding (UFLS) schemes are the latest safety measures applied for safeguarding the integrity of the grid against abrupt frequency imbalances. The overall inertia of electrical power systems is expected to decrease with an increased penetration of renewable energy as well as elements connected through power electronic interfaces. However, voltage source converter-based high voltage direct current (VSC-HVDC) links can provide virtual inertia through a control loop that allows for a reaction to occur at certain frequency fluctuations. This paper evaluates a UFLS scheme that considers the injection of virtual inertia through a VSC-HVDC link. A genetic algorithm (GA) is used to determine the location of the UFLS relays, the activation threshold of each stage, the delay time and the percentage of load shedding at each stage. It was found that the virtual inertia causes the nadir to delay and sometimes reach a greater depth. Furthermore, the implemented GA approximates the frequency response to the limits set with the constraints, reducing the load shedding but achieving a steeper nadir and a lower steady-state frequency level than traditional UFLS. The simulations were performed using the IEEE 39-bus test system. [ABSTRACT FROM AUTHOR]

Copyright of Agroalimentaria is the property of Alejandro Antonio Gutierrez Socorro and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the reliability of power supply, the sophisticated design of the structure of electric cable network has become an important issue for modern urban distribution networks. In this paper, an electric cable path planning model based on heuristic optimization algorithm considering mixed-land scenario is proposed. Firstly, based on different land samples, the kernel density estimation (KDE) and the analytic hierarchy process (AHP) are used to estimate the construction cost of each unit grid, in order to construct the objective function of comprehensive investment for electric cable loop network. Then, the ant colony optimization (ACO) was improved in pheromone concentration, factor increment and search direction to accelerate the solving speed, and the cable path planning result with minimum construction cost is obtained. Finally, the feeder’s tie line of the cable loop network is planned by the genetic algorithm (GA) to achieve the minimum operating cost. In the case analysis, compared with the traditional method, not only the subjective factors in the process of investment estimation can be avoided, but also the speed of model solving and the quality of the optimal solution are improved. [ABSTRACT FROM AUTHOR]

Recycling of hardmetal scrap is strategic for critical raw materials recovery. Available recycling processes are polluting and have a large carbon footprint. Attempts to exploit controlled corrosion failed in industrial practice, owing to self-limiting processes. We revisit the corrosion route, in view of gaining the fundamental knowledge enabling high-throughput recovery. We selected the worst-case approach of highly corrosion-resistant CoNiWC-based hardmetal grades and neutral aqueous electrolyte at room temperature. Systematic electrochemical measurements, UV–Vis spectroscopy and SEM microscopy disclosed that, even though there is no hope to overcome the self-limiting corrosion rate, nevertheless, by exploiting the mechanical action of anodic O2 evolution acting precisely at the interface between the residual active material and the corrosion film, the latter can be efficiently removed, periodically reactivating the hardmetal corrosion in a way that results in an ultra-high scrap destruction rate, of interest for real-life industrial processes. [ABSTRACT FROM AUTHOR]

This study aims to develop and characterize a flexible p-PANI/n-ZnO heterojunction diode developed from a combination of electrochemical and sputtering technique. Investigation of structural properties and morphology of the thin films has been done from XRD and SEM analysis. To study the temperature effect on the electrical properties of the diode, current–voltage–temperature (I – V – T) measurements were done for the temperature range 25–300 K. Applying the ideal thermionic emission theory, various diode parameters like reverse saturation current, quality factor, series resistance and barrier height were computed utilizing the semilogarithmic plot of I – V curve and Cheungs' method. Barrier height, reverse saturation current and quality factor calculated from ln(I) versus V curve were observed to vary from 0.0627–0.725 eV, 0.236–98.8 nA and 54.43–3.29 respectively over the temperature range 25–300 K. It has been found that the series resistance falls with a rise in temperature. The barrier height, series resistance and ideality factor were observed to vary from 0.0628–0.692 eV, 15 900–46.8 Kohm and 41.88–2.27 respectively for the temperature range 25–300 K. The activation energy estimated from Arrhenius plot was observed to be 14.51 meV. Additionally, the fabricated PANI/ZnO diode was mechanically robust that can be bent without affecting its performance. [ABSTRACT FROM AUTHOR]

Copyright of Informacion Tecnica Economica Agraria is the property of Asociacion Interprofesional para el Desarrollo Agrario (AIDA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In social robotics, especially with regard to direct interactions between robots and humans, the robotic movements of the body, arms and head must make an adequate displacement to guarantee an adequate interaction, both from a functional and social point of view. To achieve this, the use of closed-loop control techniques that consider the complex nonlinear dynamics and disturbances inherent in these systems is required. In this paper, an implementation of a nonlinear controller for the tracking of trajectories and a profile of speeds that execute the movements of the arms and head of a humanoid robot based on the mathematical model is proposed. First, the design and implementation of the arms and head are initially presented, then the mathematical model via kinematic and dynamic analysis was performed. With the above, the design of nonlinear controllers such as nonlinear proportional derivative control with gravity compensation, Backstepping control, Sliding Mode control and the application of each of them to the robotic system are presented. A comparative analysis based on a frequency analysis, the efficiency in polynomial trajectories and the implementation requirements allowed selecting the non-linear Backstepping control technique to be implemented. Then, for the implementation, a centralized control architecture is considered, which uses a central microcontroller in the external loop and an internal microcontroller (as internal loop) for each of the actuators. With the above, the selected controller was validated through experiments performed in real time on the implemented humanoid robot, demonstrating proper path tracking of established trajectories for performing body language movements. [ABSTRACT FROM AUTHOR]

Due to the exponential growth of data communications, linearity specification is deteriorating and, in high frequency systems, impedance transformation leading to power delivering from power amplifiers (PAs) to antennas is becoming an increasingly important concept. Intelligent-based optimization methods can be a suitable solution for enhancing this characteristic in the transceiver systems. Herein, to tackle the problems of linearity and impedance transformations, deep neural network (DNN)-based optimizations are employed. In the first phase, the antenna is modeled through the DNN with using the long short-term memory (LSTM) leading to forecast the load impedances in the a wide frequency band. Afterwards, the PA is modeled and optimized through another LSTM-based DNN using Multivariate Newton's Method where the optimal drain impedances are predicted from the first DNN (i.e., modeled antenna). The whole optimization methodology is executed automatically leading to enhance linearity specification of the whole system. For proving the novelty of the proposed method, monolithic microwave integrated circuit (MMIC) along with the multiple-input multiple-output (MIMO) antenna is designed, modeled, and optimized concurrently in the frequency band from 7.49 GHz to 12.44 GHz. The proposed method leads to enhancing the linearity of the transceiver in an effective way where DNN-based PA model gives rise to a solution for achieving the most optimal drain impedance through the modeled DNN-based antenna. [ABSTRACT FROM AUTHOR]

Copyright of Ra Ximhai is the property of Universidad Autonoma Indigena de Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve this problem, a new biological detection method is proposed, which makes use of the characteristics of optical transmission at the edge of the spectral band gap and sensitive to refractive index variation. When the probe light with wavelength at the edge of the Bragg band gap of porous silicon is incident on the surface of porous silicon, the change of refractive index caused by deoxyribonucleic acid (DNA) reaction in porous silicon will affect the detection light intensity transmitted from the porous silicon sensor. By analyzing the change of the average gray value of the transmitted light image, the concentration of the DNA can be obtained. [ABSTRACT FROM AUTHOR]

To realize rapid biological detection and real-time analysis, a porous silicon microcavity optical biosensor with a central wavelength of 1550 nm was designed in this study, and a detection method based on the change in the gray value of the transmitted light image was proposed. The proposed method uses a near-infrared laser at the low absorption band of porous silicon as the light source. The infrared light transmitted from the surface of the porous silicon microcavity is converted into visible light by the infrared upconversion card. The transmitted light image is recorded by the charge-coupled device, and the gray value of the image is calculated to achieve detection. The experimental results show a linear relationship between the change in the gray value and the increase in complementary DNA concentration. The limit of detection of the proposed method is approximately 4 nM. The proposed method is lable free and spectrometer free, achieves fast detection speed, and can be further applied to biological detection in porous silicon microarrays. [ABSTRACT FROM AUTHOR]

Copyright of Informador Técnico is the property of Servicio Nacional de Aprendizaje SENA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Diversitas (17949998) is the property of Universidad Santo Tomas, Facultad de Psicologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Derecho del Estado is the property of Universidad Externado de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Avances: Investigación en Ingeniería is the property of Universidad Libre, Facultad de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Porous silicon seems to be an appropriate material platform for the development of high-sensitivity and low-cost optical sensors, as their porous nature increases the interaction with the target substances, and their fabrication process is very simple and inexpensive. In this paper, we present the experimental development of a porous silicon microcavity sensor and its use for real-time in-flow sensing application. A high-sensitivity configuration was designed and then fabricated, by electrochemically etching a silicon wafer. Refractive index sensing experiments were realized by flowing several dilutions with decreasing refractive indices, and measuring the spectral shift in real-time. The porous silicon microcavity sensor showed a very linear response over a wide refractive index range, with a sensitivity around 1000 nm/refractive index unit (RIU), which allowed us to directly detect refractive index variations in the 10-7 RIU range. [ABSTRACT FROM AUTHOR]

Copyright of Mundo Agrario is the property of Universidad Nacional de La Plata and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Morphological granulometries constitute one of the most useful and versatile image analysis techniques applied to a wide range of tasks, from size distribution of objects, to feature extraction and to texture characterization in industrial and research applications where high-performance instrumentation and online signal processing are required. Since granulometries are based on sequences of openings with structuring elements (SEs) of increasing size, they are computational demanding on non-specialized hardware. In this paper, a pipelined hardware architecture for fast computation of gray-level morphological granulometries is presented, centered around two systolic-like processing arrays able to process with flat SEs of different shapes and sizes. To validate the proposed scheme, the architecture was modeled, simulated and implemented into a field programmable gate array. Implementation results show that the architecture is able to compute particle size distribution on 512 × 512 sized images with flat non-rectangular SEs of up to 51 × 51, in around 60 ms at a clock frequency of 260 MHz. It is shown that a speed up over two orders of magnitude is obtained compared to a naive software implementation. The architecture performance compares favorably to similar hardware architectural schemes and to optimized high-performance graphical processing units-based implementations. [ABSTRACT FROM AUTHOR]

In this paper, we report the results of the investigation about the optical properties of one-dimensional photonic crystals based on porous silicon multilayer structures having unit cells with optical properties that vary as a function of the device thickness. These devices were obtained by anodizing crystalline silicon in electrolyte aqueous solution of HF at different concentrations. The effective refractive index and extinction coefficients, of porous silicon layers of unit cells had been obtained by fitting the experimental reflectance spectra using the transfer matrix method. The effective-refractive indexes, for devices obtained in electrolyte solution of high HF concentration, were shown to have a significant gradient in the depth of the layers, whereas it was low (negligible) for devices obtained in electrolyte solution with low HF concentration, but the mechanical stability of these latter devices is poor. It was found that this fragility depends on the layer number and upon their physical thicknesses ratio. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.joep.2010.04.001 Byline: Ricardo Godoy (a), Elizabeth Zeinalova (a), Victoria Reyes-Garcia (a)(b)(c), Tomas Huanca (d), Holly Kosiewicz (d), William R. Leonard (e), Susan Tanner (f) Keywords: Amazon; Bolivia; Tsimane'; Markets; Trade opening; Psyche; Well-being Abstract: Despite the pervasiveness of international trade, the effects of trade opening on the psyche have received scant attention. We present three hypotheses about the likely effects of trade opening on the following five dimensions of the psyche: mirth (smiles), anger, addiction, stress, and regret. To test the hypotheses we use a survey of [approximately equal to]605 people [greater than or equal to]16years of age from a highly autarkic native Amazonian society of foragers and farmers in Bolivia (Tsimane') with high levels of impulsivity. As explanatory variables we use four measures of trade opening and a wide range of controls. Regret at buying durable assets during the previous year and addiction bore a positive association with two measures of trade opening: monetary income in the last 2 weeks and outstanding monetary debts owed to one or owed to the rest of the world. International trade theory predicts that trade opening expands choices in consumption, but among impulsive people in a highly autarkic society, more choice can beget more addiction and buyer's regret. We found no association between trade opening and smiles, anger, or stress, consistent with recent findings from industrial societies suggesting weak or ambiguous links between monetary income and these indicators of subjective well-being. Author Affiliation: (a) Heller School for Social Policy and Management, Brandeis University, Waltham, MA 02454-9110, USA (b) ICREA and Institut de Ciencia i Tecnologia Ambientals, Universitat AutA[sup.2]noma de Barcelona, 08193 Bellatera, Barcelona, Spain (c) Centro Boliviano de Investigacion y de Desarrollo Socio Integral (CBIDSI), Correo Central, San Borja, Beni, Bolivia (d) Centro de Estudios sobre el Desarrollo Economico, Universidad de los Andes, Bogota, Colombia (e) Department of Anthropology, Northwestern University, Evanston, IL 60208, USA (f) Department of Anthropology, University of Georgia, Athens, GA 30602, USA (g) Tsimane' Amazonian Panel Study (TAPS), San Borja, Beni, Bolivia Article History: Received 2 June 2008; Revised 4 March 2010; Accepted 1 April 2010

The article presents a report on market economy and the loss of folk knowledge of plant uses. It estimates from the Tsimane Indians, a foraging-horticultural society in the Bolivian Amazon. For most of human history, people's main form of knowledge has been adapted to the local environment and based on experience and empirical testing. This form of knowledge has been called folk or traditional knowledge. The disappearance of folk knowledge represents the irreversible loss of humanity's heritage and diversity. Since the 1980s anthropologists have used agreement among informants as a proxy for knowledge to study patterns of knowledge distribution within a group. Researchers have found that older people, women, and people related by kinship share more knowledge of plant uses. Researchers have also studied the effects of the market economy on knowledge of plant uses. Among the many factors that could contribute to the loss of folk knowledge of plant uses, the market economy may play a role because markets allow access to substitutes for products made from plants.

The author conducted a focused descriptive ethnographic study of nonadherence with tuberculosis (TB) therapy among Aymara-speaking residents of the city of La Paz, Bolivia. A cohort of patient-informants was identified from the District III TB Control Registry of La Paz as having been nonadherent with their TB medication protocol. From June to August 1998, ethnographic material was collected through participant-observation and repeated interviews and visits in homes, workplaces, clinics, and the community. Ethnographic analysis revealed structural barriers to be more important than cultural differences in the production of nonadherence. Though informants maintained a variety of beliefs and practices related to Aymara medicine, the majority of patients were comfortable with a biomedical model of tuberculosis and maintained belief in the efficacy of antituberculosis chemotherapy and desire to finish treatment. Patients overwhelmingly cited hidden costs of treatments, poor access to care, ethnic discrimination, and prior maltreatment by the health system as reasons for abandoning treatment. These data suggest that overemphasis of cultural difference without exploration of other social dimensions of health care delivery can obscure a more practical understanding of nonadherence in marginalized populations. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new discrete-continuous codification of the Chu–Beasley genetic algorithm to address the optimal placement and sizing problem of the distribution static compensators (D-STATCOM) in electrical distribution grids. The discrete part of the codification determines the nodes where D-STATCOM will be installed. The continuous part of the codification regulates their sizes. The objective function considered in this study is the minimization of the annual operative costs regarding energy losses and installation investments in D-STATCOM. This objective function is subject to the classical power balance constraints and devices' capabilities. The proposed discrete-continuous version of the genetic algorithm solves the mixed-integer non-linear programming model that the classical power balance generates. Numerical validations in the 33 test feeder with radial and meshed configurations show that the proposed approach effectively minimizes the annual operating costs of the grid. In addition, the GAMS software compares the results of the proposed optimization method, which allows demonstrating its efficiency and robustness. [ABSTRACT FROM AUTHOR]

We present a fast, novel method for building porous silicon-based silicon-on-insulator photonic crystals in which a periodic modulation of the refractive index is built by alternating different electrochemical etching currents. The morphology and reflectance spectra of the photonic crystals, prepared by the proposed method, are investigated. The scanning electron micrograph and atomic force microscopy images show a very uniform structure and the porous silicon demonstrates an 829 nm wide photonic band gap. [ABSTRACT FROM AUTHOR]

Obtaining light emission from silicon has been the holy grail of optoelectronics over the last few decades. One of the most common methods for obtaining light emission from silicon is to reduce it to a nanoscale structure, for example by producing porous silicon. Here, we present a method for the large-area fabrication of porous silicon microtubes by the stain etching of silicon micropillar arrays. We explain and model how the formation of the microtubes is influenced by the morphology of the substrate, especially the concave or convex character of the 3D features. Light emission is demonstrated at the micro- and nanoscale respectively by photo- and cathodoluminescence. Finally, we demonstrate a 0.55 cm2 device that can work as a photodetector with 2.3% conversion efficiency under one sun illumination, and also as a broadband light emitting diode, illustrating the applicability of our results for optoelectronic applications. [ABSTRACT FROM AUTHOR]