Resilient Operational Planning for Microgrids Against Extreme Events

This paper proposes a novel resilience index, a microgrid survivability rate (SR) under extreme events, and then proposes a novel Resilient Operational Planning (ROP) algorithm to maximize the proposed resilience index SR. The proposed ROP algorithm can incorporate predetermined inverter failure probabilities and generate multiple scenarios accordingly to optimize resilient operations during an extreme event. The implemented ROP algorithm consists of two main steps: (i) optimization of resilient operational planning, and (ii) preventive resilience enhancement if minimum SR is not met per the analysis in step 1. A typical microgrid (MG) is studied to compare the proposed ROP algorithm against a traditional microgrid energy management (MEM) model. Results indicate that an enhanced resilience operation is achieved by the ROP algorithm, which is demonstrated by the quantification of resilience via the SR. Moreover, the proposed ROP algorithm is able to obtain a greater SR overall compared to that achieved by the traditional MEM, and this benefit of using the proposed ROP increases as the inverter failure probabilities increase

Greenhouse gases emissions and electric power generation in Latin American countries in the period 2006–2013

The objective of this study is to classify the group of countries that contributes to the emissions of GHG gases in relation to their electric power generation. The data used for this classification are those reported by OLADE during the period from 2006 to 2013. The results show that they were organized in four (4) clusters, dividing them into efficient and inefficient levels. In the highest efficient level is Brazil, while in the lowest efficient level are Colombia, Costa Rica, El Salvador, Panama, Paraguay, Peru, Uruguay, and Venezuela. Argentina and Mexico are in the highest inefficient level, while the rest of the Latin American countries are in the lowest inefficient level. The countries located at the efficient and inefficient levels were labeled as most emitting countries and least emitting countries

Competencias digitales y su influencia en el desempeño docente del colegio José Carlos Mariategui, Jayanca 2021

El presente trabajo titulado Competencias Digitales y su influencia en el Desempeño Docente del colegio José Carlos Mariátegui, Jayanca 2021, tuvo como objetivo Determinar la influencia de las competencias digitales en el desempeño docente del colegio José Carlos Mariátegui, Jayanca 2021. Esta investigación es de tipo descriptiva, cuantitativa, correlacional y diseño no experimental, utilizandose una población – muestra de 18 docentes de la institución educativa Carlos Mariátegui, tanto de nivel primario como secundario. Para la obtención de datos, se utilizó como técnica la encuesta, y como instrumento un cuestionario, basado en la escala de Likert, que contuvo 10 ítems que corresponden a la variable Competencias Digitales y 10 ítems que corresponden a la variable Desempeño. Se obtuvo como resultados que los docentes están en un nivel regular con un 44% en competencias digitales, y además están en un nivel regular en cuanto a su desempeño en la institución con un 50%. Se concluyó que las dimensiones que más influyen en el desempeño docente, es la comunicación y colaboración, creación de contenidos y resolución de problemas, y al obtener p=0,00, se demostró y se verificó que las competencias digitales influyen en el desempeño docente del colegio José Carlos Mariátegui, Jayanca 2021.TesisGestión empresarial y emprendimient

Differential effects of tau stage, Lewy body pathology, and substantia nigra degeneration on FDG-PET patterns in clinical AD

PURPOSE: Comorbid Lewy body (LB) pathology is common in AD. The effect of LB co-pathology on FDG-PET patterns in AD is yet to be studied. We analysed associations of neuropathologically-assessed tau pathology, LB pathology, and substantia nigra neuron loss (SNnl) with ante-mortem FDG-PET hypometabolism in patients with a clinical AD presentation. METHODS: Twenty-one patients with autopsy-confirmed AD (‘pure-AD’), 24 with AD and LB co-pathology (‘AD-LB’), and 7 with LB but no or low evidence of AD pathology (‘pure-LB’) were studied. Pathologic groups were compared on regional and voxel-wise FDG-PET patterns, the cingulate island sign ratio (CISr), and neuropathological ratings of SNnl. Additional analyses assessed continuous associations of Braak tangle stage and SNnl with FDG-PET patterns. RESULTS: Pure-AD and AD-LB showed highly similar patterns of AD-typical temporo-parietal hypometabolism and did not differ in CISr, regional FDG SUVR, or SNnl. By contrast, pure-LB showed the expected DLB-like pattern, accompanied by pronounced occipital hypometabolism and elevated CISr and SNnl compared to the AD groups. In continuous analyses, Braak tangle stage was significantly correlated with more AD-like, and SNnl with more DLB-like, FDG-PET patterns. CONCLUSIONS: In autopsy-confirmed AD dementia patients, comorbid LB pathology did not have a notable effect on the regional FDG-PET pattern. A more DLB-like FDG-PET pattern was observed in relation to SNnl, but advanced SNnl was mostly limited to relatively pure LB cases. AD pathology may have a dominant effect over LB pathology in determining the regional neurodegeneration phenotype

PLANEACIÓN DIDÁCTICA GENERAL DE LA ASIGNATURA: FILOSOFÍA

GUÍA DIDÁCTICA / PLANEACIÓN DIDÁCTICA (NMS

Effect of Boriding on the Mechanical Properties of AISI 1045 Steel

Efecto en las propiedades mecánicas de un acero borurado 1045.Some mechanical properties of AISI 1045 borided steels were estimated in the present work. The boriding process was carried out by the powder pack method at 950°C with 8 h of treatment. The fatigue strength on borided notched specimens was evaluated with rotating bending tests (R=1) considering a stress concentration factor (Kt) of 2.53. Likewise, the presence of residual stresses in boride layers was established by the XRD technique. The Daimler-Benz Rockwell C test was used, also, to estimate the strength adhesion of the coated system. The results show a decrease in the fatigue strength of AISI borided steels due to the presence of high porosity in the layers. Finally, the Rockwell-C adhesion test showed no coating failure for the boride layer

Technical and market evaluation of thermal generation power plants in the Colombia power system

Thermal power plants are the widely conventional generation unit technology used to produce electricity being controllable and dispatchable. The location of thermal power plants depends on the energy availability conditions of the areas and the capacity to fuels access. Their location and geographical distribution define a high level of concentration in areas defined as thermal districts and its location define reliability, security, availability, and flexibility indices to avoid critical scenario or support system from contingencies. However, in many cases the electrical configuration does not correspond to requirements. This paper links the concentration by political distribution in Colombia and the configuration used in the generating substations to guarantee requirements. The Hirschman-Herfindahl index as a market tool is used to evaluate energy concentration facing representative participation in certain departments of Colombia. Results evidenced configurations and concentration in a study case, results and analysis could be used for planner to promote participation, reliability and promote. The paper’s contribution and conclusions are linked to guide planners towards market and technical tool to evaluate installed capacities, avoid market concentration, and reduce risky scenarios

GRUPOS ECOLÓGICOS E A DISPERSÃO DE SEMENTES DE ESPÉCIES ARBÓREAS EM TRECHO DA FLORESTA TROPICAL NA RESERVA FLORESTAL DE LINHARES (ES)

No presente estudo procurou-se avaliar os diferen­tes grupos ecológicos e os processos de dispersão predominantes para espécies arbóreas em trecho da floresta tropical na Reserva Florestal de Unhares (ES). Foram avaliadas 227 espécies. 57% enquadraram-se no grupo ecológico das secundárias, 23% no de pionei­ras e20% nos de tolerantes. 74% apresentavam síndrome de dispersão zoocórica, 24% anemocórica e apenas 4% aulocórica. Os autores concluíram que, para a floresta estudada, a sucessão depende, principalmente, da ação dos agentes dispersores bióticos

PLANEACIÓN DIDÁCTICA GENERAL DE LA ASIGNATURA DE ÉTICA

GUÍA DIDÁCTICA / PLANEACIÓN DIDÁCTICA (NMS