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In arid and semiarid regions, crop production has high irrigation water demands due to low precipitation. Efficient irrigation water management strategies can be developed using crop growth models to assess the effect of different irrigation management practices on crop productivity. The leaf area index (LAI) is an important growth parameter used in crop modeling. Measuring LAI requires specialized and expensive equipment not readily available for producers. Canopy cover (CC) and canopy height (CH) measurements, on the other hand, can be obtained with little effort using mobile devices and a ruler, respectively. The objective of this study was to determine the relationships between LAI, CC, and CH for fully and deficit-irrigated alfalfa (Medicago sativa L.). The LAI, CC, and CH measurements were obtained from an experiment conducted at the Valley Road Field Lab in Reno, Nevada, starting in the Fall of 2020. Three irrigation treatments were applied to two alfalfa varieties (Ladak II and Stratica): 100%, 80%, and 60% of full irrigation demands. Biweekly measurements of CC, CH, and LAI were collected during the growing seasons of 2021 and 2022. The dataset was randomly split into training and testing subsets. For the training subset, an exponential model and a simple linear regression (SLR) model were used to determine the individual relationship of CC and CH with LAI, respectively. Also, a multiple linear regression (MLR) model was implemented for the estimation of LAI with CC and CH as its predictors. The exponential model was fitted with a residual standard error (RSE) and coefficient of determination (R2) of 0.97 and 0.86, respectively. A lower performance was obtained for the SLR model (RSE = 1.03, R2 = 0.81). The MLR model (RSE = 0.82, R2 = 0.88) improved the performance achieved by the exponential and SLR models. The results of the testing indicated that the MLR performed better (RSE = 0.82, R2 = 0.88) than the exponential model (RSE = 0.97, R2 = 0.86) and the SLR model (RSE = 1.03, R2 = 0.82) in the estimation of LAI. The relationships obtained can be useful to estimate LAI when CC, CH, or both predictors are available and assist with the validation of data generated by crop growth models.

Abstract Climate change‐induced shifts in snow storage and snowmelt patterns pose risks for adverse impacts to people, the environment, and irrigated agriculture. Existing research primarily focuses on evaluating these risks to irrigated agriculture at large scales, overlooking the role of local context in shaping risk dynamics. Consequently, many “at‐risk” areas lack insight into how adaptation strategies for managing risk through water supply augmentation or water conservation vary across contexts and over time. To address this gap, we develop a comprehensive index for evaluating irrigated agriculture's risk and adaptation potential to changes in snow at local scales and apply it throughout the western US. Results confirm trends toward escalating risk for changes in snow storage and snowmelt patterns over the century. However, substantial heterogeneity in the extent and drivers of risk exists due to variability in localized interactions between declines in water supply (approximately −9% ± 13% by 2100) and increased agricultural demand (approximately 7% ± 5% by 2100). Despite an existing focus on supply augmentation as a critical adaptation strategy to reduce risk, we show its effectiveness diminishes for many areas over time, declining to an average of −54% of historical augmentation potential by 2100. Conserving water through historical changes in crop acreage and type emerges as a more stable adaptation measure, reducing demand by 7%–8% regardless of time. While particularly relevant for higher elevation, less intensive agricultural settings in snowmelt‐dependent regions, findings underscore the need for strategies that support local‐scale, context‐appropriate adaptation to effectively manage escalating risk as snow changes.

Increasing pressure over water resources in the western U.S. is currently forcing alfalfa (Medicago sativa L.) producers to adopt water-saving irrigation techniques. Crop yield forecasting tools can be used to develop smart irrigation scheduling methods that can be used to estimate the future effects of a given irrigation amount applied during a current irrigation event on yield. In this work, a linear model and a random forest model were used to estimate the yield of irrigated alfalfa crops in northern Nevada. It was found that water (rain + irrigation), the occurrence of extreme temperatures, and wind have a greater effect on crop yield. Other variables that accounted for the photoperiod and the dormant period were also included in the model and are also important. The linear model had the best performance with an R2 of 0.854. On the other hand, the R2 value for the random forest was 0.793. The linear model showed a good response to water variability; therefore, it is a good model to consider for use as an irrigation decision support system. However, unlike the linear model, the random forest model can capture non-linear relationships occurring between the crop, water, and the atmosphere, and its results may be enhanced by including more data for its training.

Abstract Electrical power systems are continuously upgrading into networks with a higher degree of automation capable of identifying and reacting to different events that may trigger undesirable situations. In power systems with decreasing inertia and damping levels, poorly damped oscillations with sustained or growing amplitudes following a disturbance may eventually lead to instability and provoke a major event such as a blackout. Additionally, with the increasing and considerable share of renewable power generation, unprecedented operational challenges shall be considered when proposing protection schemes against unstable electro‐mechanical (e.g. ringdown) oscillations. In an emergency situation, islanding operations enable splitting a power network into separate smaller networks to prevent a total blackout. Due to such changes, identifying the underlying types of oscillatory coherency and the islanding protocols are necessary for a continuously updating process to be incorporated into the existing power system monitoring and control tasks. This paper examines the existing evaluation methods and the islanding protocols as well as proposes an updated operational guideline based on the latest data‐analytic technologies.

The transient stability analysis of large-interconnected power systems using time-domain simulations (TDS) is a significant challenge since it represents a huge computational cost. Besides, for dynamic security assessment is required have a quick response. Consequently, recent approaches are relying on using the wide-area measurement system combined with other techniques to perform transient stability assessment and counteract the drawbacks of the TDS method. However, these approaches still requiring to perform TDS to set initial parameters. This paper proposes a new algorithm to estimate the critical clearing time (CCT) based on the eigenvalue calculation and the singular value decomposition using data from wide-area measurement systems. The proposed algorithm uses the phase angles of the voltage phasors measurements at the generation buses to represent the dynamics of the internal angles of the generators. First, from a set of signals, a measurement matrix is formed using a sliding window. Then, a threshold based on the maximum singular value and the dominant eigenvalue of the measurement matrix are computed. Finally, the CCT is estimated using the dominant eigenvalue (the most energetic eigenvalue) and the threshold. The proposed algorithm is evaluated using the Kundur four-machine system and New England 39-Bus system. Its performance contrasts to the CCT calculated using the classical TDS. The simulation results demonstrated acceptable precision of the CCT against TDS. Also, it presents robustness against the effect of the noise in the measurements. Therefore, it is suitable for online applications.

The power system continuously deals with frequency fluctuations. When a power disturbance occurs, the transmission system operators rely on the underfrequency load shedding (UFLS) scheme to address severe underfrequency (UF) events to maintain the frequency at the permissible level and prevent blackouts. Defining settings of a conventional UFLS scheme is a very complex problem due to the nonlinear nature of the frequency response, and the size of the problem is vast because of the number of UF-relays spread on the power system. The under or over total load disconnection produced by the wrong setting of the UF-relays can create secondary frequency events or even a total blackout. This paper introduces a novel method to compute an optimally parametrized conventional UFLS scheme in specific given operating conditions by formulating it as a constrained problem and using the Improved Harmony Search (IHS) algorithm to solve it. Since there is no previous knowledge of using IHS to solve the UFLS scheme, a numerical parameter sensitivity analysis (PSA) is developed to tune the parameter of the IHS algorithm. The IEEE 39-bus system was modelled in DIgSILENT® PowerFactory™ and used as a test system. The optimally parametrized conventional UFLS methodology presented in this paper reveals superior results against the conventional UFLS scheme, and the suitability of using the IHS algorithm is confirmed.

Abstract Advances in environmental and agricultural management are increasingly enabled by unattended data acquisition using internet‐of‐things (IOT) approaches. These approaches combine advanced sensors and wireless data transmission to automatically convey field data to the internet. Users, either human or machine, then can access and act upon the data from nearly anywhere in the world. Particularly in the case of machines automatically acting on the data, robustness, reliability and accuracy of data are crucial to preventing unintended outcomes of machine operations and continued supply of key services. Low‐cost, low‐power, and solar‐powered systems are important to enable market entry of advanced decision support systems based on IOT data acquisition approaches. The polar vortex outbreak of February 2021 in the central United States provided an extreme test of such a node and gateway system for automatic data acquisition and telemetry to the internet over the cellular telephone network. The system, codesigned by USDA‐ARS and Acclima, performed admirably despite air temperatures reaching a minimum of −24 °C, temperatures < 0 °C for 8 d and < −7 °C for 6 d, two snowstorms, and overcast conditions. The six nodes, gateway, and 36 sensors continued to function reliably with a data transmission failure rate of

The reactive power control mechanisms at the smart inverters will affect the voltage profile, active power losses and the cost of reactive power procurement in a different way. Therefore, this paper presents an assessment of the cost–benefit relationship obtained by enabling nine different reactive power control mechanisms at the smart inverters. The first eight reactive power control mechanisms are available in the literature and include the IEEE 1547−2018 standard requirements. The ninth control mechanism is an optimum reactive power control proposed in this paper. It is formulated to minimise the active power losses of the network and ensure the bus voltages and the reactive power of the smart inverter are within their allowable limits. The Vestfold and Telemark distribution network was implemented in DIgSILENT PowerFactory and used to evaluate the reactive power control mechanisms. The reactive power prices were taken from the default payment rate document of the National Grid. Simulation results demonstrate that the optimal reactive power control mechanism provides the best cost–benefit for the daily steady-state operation of the network.

The replacement of conventional generation sources by DER creates the need to carefully manage the reactive power maintaining the power system safe operation. The principal trend is to increase the DER volume connected to the distribution network in the coming years. Therefore, the microgrid represents an alternative to offer reactive power management due to excellent controllability features embedded in the DER, which enable effective interaction between the microgrid and the distribution network. This paper proposes a microgrid–iterative reactive power management approach of power-electronic converter based renewable technologies for day-ahead operation. It is designed to be a centralised control based on local measurements, which provides the optimal reactive power dispatch and minimise the total energy losses inside the microgrid and maintain the voltage profile within operational limits. The proposed optimal-centralised control is contrasted against seven local reactive power controls using a techno-economic approach considering the steady–state voltage profile, the energy losses, and the reactive power costs as performance metrics. Three different reactive power pricing are proposed. The numerical results demonstrate the optimal microgrid–interactive reactive power management is the most suitable techno-economic reactive power control for the day–ahead operation.

The Altai-Uliastai regional power system (AURPS) is a regional power system radially interconnected to the power system of Mongolia. The 110 kV interconnection is exceptionally long and susceptible to frequent trips because of weather conditions. The load-rich and low-inertia AURPS must be islanded during interconnection outages, and the under-frequency load shedding (UFLS) scheme must act to ensure secure operation. Traditional UFLS over-sheds local demand, negatively affecting the local population, especially during the cold Mongolian winter season. This research paper proposes a novel methodology to optimally calculate the settings of the UFLS scheme, where each parameter of the scheme is individually adjusted to minimise the total amount of disconnected load. This paper presents a computationally efficient methodology that is illustrated in a specially created co-simulation environment (DIgSILENT® PowerFactoryTM + Python). The results demonstrate an outstanding performance of the proposed approach when compared with the traditional one.

The integration of renewable resources is quickly growing in the Nordic power system (NPS), and it has led to increasing challenges for the operation and control of the NPS. Nordic countries require that the first-generation power plants have a more flexible operation regime to overcomes power imbalances coming from fluctuations of the demand and supply. This paper assesses optimal frequency support of variable-speed hydropower plants installed in Telemark and Vestfold, Norway, considering future scenarios of NPS. The total kinetic energy of the NPS is expected to be significantly reduced in the future. This paper looks into the implementation of hydropower units with a variable-speed operation regime and battery energy storage systems (BESS), equipped with fast-active power controller (FAPC) technology, to provide fast frequency response after a system frequency disturbance. The frequency support was formulated as an optimization process; therefore, the parameter of the FAPC was optimally calculated for future scenarios of low inertia in NPS. Three main futures scenarios were developed for technology penetration in the Vestfold and Telemark area in Norway. The simulation results showed that the integration variable-speed hydropower units and BESS technologies improved the frequency response even in low-kinetic energy scenarios.

As Humanidades Digitais, assim como a abordagem textual proposta pela Nova Filologia, trouxeram consigo mudanças profundas no modo como hoje se faz investigação em Humanidades e vieram permitir a conceção de projetos ambiciosos, que requerem equipas pluridisciplinares e internacionais. Assim, após uma reflexão sobre a génese e o âmbito das Humanidades Digitais e da Nova Filologia, apresentaremos uma seleção de projetos de investigação, nacionais e internacionais, exemplificativos da aplicação prática destes campos aos Estudos Linguísticos e Literários e à História, evidenciando o seu contributo para a preservação, análise e compreensão mais profunda de corpora vários. Dar-se-á particular ênfase a projetos que demonstram a aplicabilidade inovadora e profícua das Humanidades Digitais e da Nova Filologia ao estudo de corpora epistolares (com especial incidência em cartas médicas e consilia), ao proporcionarem um conhecimento circunstanciado e abrangente do conteúdo dos textos que os integram, elucidando aspetos cruciais como a identidade dos correspondentes, a natureza dos laços que os uniam, ou o contexto sociopolítico e cultural em que se moviam. Por último, à luz dos avanços realizados neste campo de estudo, apresentar-se-á a conceção de um novo projeto de investigação, centrado num conjunto inédito de epistolae medicinales e de consilia de Jorge Godines, um médico português do século XVI.

Background: Speech-language therapists and audiologists (SLT&As) may encounter difficulties when confronted with patient death and dying, which may conflict with their moral beliefs and result in moral injury. Furthermore, South African SLT&As practice in a country with a high mortality rate, which may add to the complexity of their experience. Moreover, they may be influenced by African philosophies promoting care, which might conflict with their experiences of patient death and dying. Aims: To explore the moral injury experienced by South African SLT&As in patient death and dying, and how they overcame the injury. Methods & Procedures: This article forms part of a larger qualitative study that explored SLT&As' experiences of patient death and dying in South Africa. Thematic analysis was conducted on the transcripts of 25 episodic narrative interviews conducted with South African SLT&As on their experiences of patient death and dying. Outcomes & Results: Findings suggest that South African SLT&As experienced helplessness, guilt and anger in patient death and dying. However, with support from the allied team, engaging in self-reflection and religious practices, they reported alleviation of moral injury. Conclusions & Implications: In order to mitigate moral injury in South African SLT&As, they require professional education, self-care strategies, guidelines and support from the teams in which they work and their supervisors. Research is needed that explores how SLT&As' biographical characteristics and interactions with significant others of dying and deceased patients, may result in moral injury.

Supply chain coordination (SCC) can be a challenge for many organizations as different firms in the same chain has different expectations and interdependencies (Arshinder & Deshmukh, 2008). Lack of SCC can result in the bullwhip effect and poor performance for a firm and its partners. By investigating the phenomenon in the Brazilian pharmaceutical supply chain using a qualitative research, this paper aims to understand the main issues that avoid a better integrated chain. Results of 21 interviews suggested that the lack of coordination in this environment was influenced by the network design and the history of the sector in Brazil, as well as scarce resources. [ABSTRACT FROM AUTHOR]

Las plataformas tecnológicas mediante el uso de herramientas digitales y datos en tiempo real permiten optimizar las operaciones del sector transporte de carga terrestre, reducir el consumo de energía y las emisiones de gases de efecto invernadero; posibilitando un transporte más eficiente y sostenible en el país. La metodología implementada en el cumplimiento de los objetivos se relacionó con la preparación del software para el proceso de instalación, el desarrollo e integración de la plataforma tecnológica, la realización de guía de formación y capacitación para el uso de la tecnología, el plan de descarga e instalación de la plataforma en los vehículos (Instalaciones del prototipo software en los vehículos de carga terrestres), y la parametrización del sistema con pruebas de validación. El estudio se desarrolló sobre varios tipos de vehículos de transporte terrestre de carga pesada, camiones rígidos, tractocamiones, los vehículos cerrados tipo furgones; impactando en esta fase piloto el 0.1% del parque automotor existente en Colombia. Con potenciales de ahorro de energía sin cambios tecnológicos del 20%, los cuales se deben exclusivamente a los hábitos operacionales y la cultura energética de los operadores. La plataforma tecnológica propuesta en este proyecto en transversal a los tipos de vehículos de transporte de carga pesada más comunes en Colombia.

Due to the high stability of azo-type dyes, conventional treatment processes such as adsorption, flocculation, and activated sludge are not efficient for decolorizing wastewater effluents. An alternative to traditional wastewater treatment is photocatalysis, which has gained significant interest because research has shown it to be a viable and cost-effective process that uses sunlight as an inexhaustible energy source. In heterogeneous photocatalysis, a photocatalyst is required, such as TiO2, ZnO, composite materials, and, more recently, metal–organic frameworks (MOFs). MOFs, also known as “coordination polymers”, exhibit photocatalytic properties and have been proven to be promising materials in the photocatalytic degradation of dyes. This study presents recent advances in using MOFs as photocatalysts to degrade recalcitrant contaminants like azo-type dyes. Recent advancements in developing photocatalysts based on MOFs are focused on two strategies. Firstly, the development of new MOFs composed of complex ligands or a mixed ligand system, and secondly, the synthesis of composite materials based on MOFs and metal oxides, metals, sulfides, nitrides, etc. Both strategies have significantly contributed to the search for new semiconductors to degrade some recalcitrate contaminants in wastewater.

En este artículo mostraré algunos de los resultados de mi investigación sobre experiencias en Esfuerzos de Cambio de Orientación Sexual e Identidad de Género (ECOSIG) en México. En específico, me centro en los aspectos violentos presentes en la vida de mis colaboradores con relación a su sexualidad y su experiencia en estas prácticas. Se presentan en primera instancia durante la infancia a través de los diferentes mecanismos de masculinización. Estos son en sí ya mecanismos para corregir y anular la expresión de género diferente a la socialmente esperada. Finalmente, se presentan experiencias con mayor cantidad de violencia al ser sometidos a técnicas que buscan modificar su orientación sexual o su identidad y expresión de género.

The aim of this paper is to analyze the mechanisms that the Spanish language uses to designate the smells understood them as a semantic field from the perspective of ethnosemantics and anthropological linguistics. We done the study in two levels. In the first one, we analyze the syntactic structure of a series of expressions that refer to the semantic field of odor, and, from this, we propose a cognitive model to analyze the semantic structure of these expressions and others obtained from dictionaries.

Se presenta el caso de un paciente de 32 años que presentó síntomas de fibrilación ventricular mientras estaba practicando una maratón. El estudio diagnóstico puso de manifiesto la existencia de un origen anómalo de la arteria coronaria derecha en el seno coronario izquierdo, con trayecto no intramural entre la aorta y la arteria pulmonar. La reparación quirúrgica consistió en la realización de una anastomosis laterolateral de la coronaria derecha al seno aórtico derecho. El postoperatorio del paciente transcurrió con normalidad. El origen aórtico anómalo de las coronarias es una alteración congénita rara asociada a un mayor riesgo de muerte súbita. En muchos casos la enfermedad es asintomática hasta producirse el infarto o la arritmia ventricular. Cuando la coronaria sigue un trayecto intramural la corrección mediante el unroofing es la técnica más empleada. Si no hay trayecto intramural y la translocación no es posible, la técnica descrita constituye una alternativa válida.

The Pacific white shrimp, Litopenaeus vannamei (Penaeidae), represents about 95% of all Brazilian shrimp production. The Brazilian L. vannamei foundation broodstock was made up of specimens collected from different American Pacific sites, but little information was collected on the genetic structure of the broodstock. We used the fluorescence amplified fragment length polymorphism (fAFLP) method to study the genetic diversity of L. vannamei broodstock lines 03CMF1 and 03CBF1 originally produced by breeder-shrimps imported mainly from Panama and Ecuador, although wild individuals from other localities may also have been used in producing these two lines. Our results showed a total of 93 polymorphic bands ranging from 50 to 500 bp, the mean Nei's genetic diversity calculated for the total sample was 13.4% and identity and genetic distance analyses indicated high genetic homogeneity within and between both the broodstock lineages studied which suggests that they had similar genetic structure. These results may represent an important tool for the appropriate management of L. vannamei broodstocks.

Durante o ano de 2013 realizou‐se uma série de ações no âmbito do projeto de investigação «Dioscórides e o Humanismo Português: os Comentários de Amato Lusitano», financiado pela Fundação para a Ciência e a Tecnologia. Todas as atividades e demais informação sobre o projeto encontram‐se disponíveis na página http://amatolusitano.web.ua.pt, onde é possível encontrar, em Português e Inglês, uma descrição pormenorizada: apresentação, equipa de investigação, publicações, eventos e dados biobibliográficos sobre Dioscórides, Amato Lusitano e Pietro Andrea Mattioli. (...)

Na sequência da realização do Colóquio Internacional “Inventários, Livros e Ciência”, que teve lugar no Arquivo Distrital de Aveiro e no Museu de Aveiro, nos dias 15 e 16 de Março de 2012, tomámos a decisão de promover a edição deste número especial da Ágora. Estudos Clássicos em Debate, propondo aos participantes que submetessem os seus trabalhos para publicação na revista. (...)

Os autos-de-fé de Ancona, entre Abril e Junho de 1556, durante o pontificado de Paulo IV, constituíram um dos episódios mais trágicos da diáspora sefardita na Península Itálica, no qual foram martirizados cerca de três dezenas de judeus portugueses. Os comissários papais começaram por apreender, inventariar e avaliar os bens de inúmeros membros da comunidade judaico-portuguesa, entre os meses de Agosto e Novembro de 1555, pouco depois da ascensão do cardeal Carafa ao sólio pontifício. Entre aqueles que viram os seus bens arrolados (subsistem 48 inventários), encontram-se dois reputados médicos, Amato Lusitano e Francisco Barbosa, e um boticário, Joseph Molcho, um dos mártires dos autos-de-fé. Este trabalho pretende fazer a contextualização destes acontecimentos, centrada na situação particular vivida por estas três figuras da Nação Portuguesa, bem como proceder ao estudo circunstanciado dos inventários dos seus bens. Raros testemunhos documentais dos ambientes domésticos e profissionais construídos por estas figuras da comunidade judaico-portuguesa, permitem estes inventários um conhecimento intimista e um acesso privilegiado, mesmo que mera aproximação, às suas actividades e personalidades, pelo tipo de objectos que escolheram ou puderam reunir em torno de si ou dos seus núcleos familiares.

Marcial conhecia como ninguém a cidade de Roma e serve de guia aos leitores da actualidade através das ruas labirínticas da Urbe. Essa cidade apresentava características específicas que dificultavam a circulação quer de pessoas quer de viaturas, apesar dos esforços de alguns políticos para irem melhorando o tecido urbano.

A fábula reúne características muito particulares que fizeram com que fosse adoptada, desde tempos recuados, com uma marcada intenção educativa, tanto na esfera da dimensão moral, como na da puramente linguística. Diogo Pires deixa-nos um valioso testemunho do lugar de eleição que a fábula ocupava no exercício da prática pedagógica humanista, porquanto reservou algum espaço na sua obra poética a este género literário, seja pela composição propriamente dita de algumas fábulas, seja pela simples alusão a outras em dísticos morais. Este estudo tem por objectivo apresentar e analisar este interessante conjunto de poemas que fazem parte, na sua totalidade, da colectânea intitulada Cato Minor siue Disticha Moralia, que saiu a lume, em duas edições venezianas, na última década de Quinhentos.

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Os pronomes latinos, designados genericamente como demonstrativos pela gramática tradicional, formam um sistema complexo, no qual cada elemento desempenha uma ou mais funções próprias e distintivas. A série deíctica/demonstrativa (hic, iste, ille) e a série fórica (is, idem, ipse) apresentam-se como os dois pilares de um sistema que se manteve, com alguma estabilidade, até ao latim tardio, período a partir do qual sofre uma reestruturação completa. A posição central que este sistema ocupa, em latim como em outras línguas, no âmbito da actualização da referência (ego, hic et nunc), justifica que se proceda também a uma análise e reflexão sobre o tratamento da questão nas gramáticas e manuais de latim portugueses actualmente à disposição dos docentes do ensino secundário.