Nondipole effects in processes assisted by a THz field having the strength of a few MV/cm can be significant due to its long wavelength. We illustrate this for strong-laser-field-induced ionization assisted by a THz field. To this end, we generalize our strong-field-approximation theory so that it includes the first-order term in a 1/c expansion of the vector potential. We show that in this case, in addition to a shift of the maximum of the photoelectron momentum distribution, the differential ionization probability as well as the cutoff energy can be significantly increased. For an explanation of these unexpected results we use the saddle-point method adjusted to include nondipole effects.
This paper presents a simulation study of a first order plus dead time system (FOPDT) controlled with proportional integral derivative (PID) controller tuned by optimizing several objective functions and treating several different scenarios. Objective functions used are Integral of Absolute Magnitude of Error (IAE), Integral of Time multiplied by the Absolute Error (ITAE), Integral of the Square Error (ISE), Integral of Time multiplied by the Square Error (ITSE) and Mean of the Integral Square Error (MISE). Scenarios include unit step response and total energy effort analysis: with and without disturbance present, unit step response in case of model to true system mismatch in time constants. Time constants being dominant time constant of the process and dead time constant. optimization algorithm used is particle swarm optimization (PSO) algorithm.
Multi-agent modeling is suitable to simulate complex interaction dynamics of microscopic urban road traffic. Valuable motion predictions can systematically be generated and exchanged among the participants (agents) to study and quantity benefits of advanced V2X-communication, for example. However, such predictions are inherently uncertain which needs to be considered for traffic safety. This work proposes a stochastic motion prediction and evaluation approach suitable for multi-agent-based simulation and control. Dynamic occupancy probability grid maps are constructed, and their interpretation clearly shows the uncertainty generated by unknown road user intentions or traffic interactions. By formulating joint occupancy probability maps, a quantification of near-accident risk becomes possible which seems to be a promising tool to examine safety aspects in “non-critical” traffic situations. The studies are based on published naturalistic driving measurement data, and both data-based as well as model-based predictions are discussed.
The content of micro- and macroelements in dry wild and edible Morchella esculenta and Lactarius piperatus mushrooms collected in Bosnia and Herzegovina was determined using the ICP-OES (inductively coupled plasma optical emission spectrom- etry) technique. The contents of microelements in M. esculenta and L. piperatus expressed in mg kg −1 DW (dry weight) were as follows: Co 0.08 and 0.28, Cu 37.35 and 27.66, Fe 174.29 and 28.11, Mn 21.26 and 19.31, Se 0.46 and 0.52, Zn 122.84 and 45.06, Al 27.80 and 24.80, Cr 0.83 and 1.06, Ni 0.99 and 0.96, As 0.32 and 0.09, Cd 0.48 and 0.13, and Pb 0.61 and 0.12, respectively, while the contents of macroelements were: K 26989.48 and 36117.20, Na 70.85 and 28.60, Ca 643.48 and 271.93, Mg 684.16 and 840.64, S 2329.33 and 610.42, and P 10339.35 and 5107.63, respectively. In this study, the potential health risks of heavy metals were assessed, and target hazard quotient (THQ) for As, Cd, Pb, Cu, Zn, Ni, and Cr in the tested mushrooms was lower than the safe level. Edible wild mushrooms M. esculenta and L. piperatus , according to this study, could be used in human nutrition due to their favourable characteristics. Based on the accumulations of heavy metals in the tested mushrooms, it was shown that the collection surfaces are environmentally acceptable. Mushrooms collected from this area are generally safe to eat and pose no health risks to humans.
Global seismographic networks (GSNs) emerged during the late nineteenth and early twentieth centuries, facilitated by seminal international developments in theory, technology, instrumentation, and data exchange. The mid‐ to late‐twentieth century saw the creation of the World‐Wide Standardized Seismographic Network (1961) and International Deployment of Accelerometers (1976), which advanced global geographic coverage as seismometer bandwidth increased greatly allowing for the recording of the Earth's principal seismic spectrum. The modern era of global observations and rapid data access began during the 1980s, and notably included the inception of the GEOSCOPE initiative (1982) and GSN (1988). Through continual improvements, GEOSCOPE and the GSN have realized near‐real time recording of ground motion with state‐of‐art data quality, dynamic range, and timing precision to encompass 180 seismic stations, many in very remote locations. Data from GSNs are increasingly integrated with other geophysical data (e.g., space geodesy, infrasound and Interferometric Synthetic Aperture Radar). Globally distributed seismic data are critical to resolving crust, mantle, and core structure; illuminating features of the plate tectonic and mantle convection system; rapid characterization of earthquakes; identification of potential tsunamis; global nuclear test verification; and provide sensitive proxies for environmental changes. As the global geosciences community continues to advance our understanding of Earth structure and processes controlling elastic wave propagation, GSN infrastructure offers a springboard to realize increasingly multi‐instrument geophysical observatories. Here, we review the historical, scientific, and monitoring heritage of GSNs, summarize key discoveries, and discuss future associated opportunities for Earth Science.
Introdução: A fibromialgia é uma síndrome dolorosa muito comum na prática clínica, caracterizada, principalmente, por dor musculoesquelética crônica e generalizada, bem como fadiga, rigidez articular e distúrbios do sono. No entanto, possui uma apresentação clínica bastante vasta e heterogênea, comprometendo diversas esferas da vida dos pacientes. O objetivo foi verificar a efetividade das terapias em grupo na qualidade de vida dos pacientes fibromiálgicos. Método: Trata-se de uma revisão sistemática, a qual buscou analisar as pesquisas relacionadas ao tema entre 2010 e 2020. A busca dos artigos ocorreu na BVS nas bases de dados LILACS e MEDLINE, sendo incluídos apenas artigos originais disponíveis na íntegra. Resultados: Foram encontradas 86 publicações científicas e, após exclusão de duplicados, aplicação de filtros e análise inicial, foram selecionados 6 artigos para compor o corpo amostral. Posteriormente, os artigos foram agrupados de acordo com a sua temática central em: 1) Efeitos positivos da terapia interdisciplinar em grupo nos sintomas físicos e psicossociais da fibromialgia; 2) Empoderamento do paciente no enfrentamento da fibromialgia; e 3) Qualidade da assistência profissional e a rede de apoio social da terapia em grupo. Conclusão: Verificou-se que a aplicação das terapias em grupos impactou, positivamente, a qualidade de vida dos pacientes em sua dimensão física, psicoemocional e social. Além disso, concluiu-se que incluir o paciente como protagonista do seu tratamento e construir uma rede de apoio são fundamentais para o enfrentamento da doença.
ABSTRACT The main goal of every company is to gain as much profit as possible, and a very important goal is also to obtain a competitive advantage in the market. In this paper, it has been developed and applied an integrated model, which is based on a PCA-DEA-MCDM approach, with the aim of evaluating the efficiency of a transport company from Bosnia and Herzegovina. At the very beginning, using the PCA (Principal Component Analysis)–DEA (Data Envelopment Analysis) model, efficient and inefficient business years were identified, and then, using CRITIC (Criteria Importance Through Inter Criteria Correlation) and the Entropy method, weight values of defined parameters were determined. After that, the decision-making units were ranked using MARCOS (Measurement Alternatives and Ranking according to the Compromise Solution). In addition, the sensitivity analysis includes the formation of scenarios of changes in weight values of five most significant criteria and the calculation of SCC and WS correlation coefficients. The application of this integrated model, in addition to identifying efficient/inefficient years of operation, enables the identification of influencing factors of the most efficient year of operation, which can serve as a benchmark to further contribute to the efficiency of the transport company.
An outbreak of acute hepatitis of unknown aetiology in children was reported in Scotland^ 1 in April 2022 and has now been identified in 35 countries^ 2 . Several recent studies have suggested an association with human adenovirus with this outbreak, a virus not commonly associated with hepatitis. Here we report a detailed case–control investigation and find an association between adeno-associated virus 2 (AAV2) infection and host genetics in disease susceptibility. Using next-generation sequencing, PCR with reverse transcription, serology and in situ hybridization, we detected recent infection with AAV2 in plasma and liver samples in 26 out of 32 (81%) cases of hepatitis compared with 5 out of 74 (7%) of samples from unaffected individuals. Furthermore, AAV2 was detected within ballooned hepatocytes alongside a prominent T cell infiltrate in liver biopsy samples. In keeping with a CD4^+ T-cell-mediated immune pathology, the human leukocyte antigen (HLA) class II HLA-DRB1*04:01 allele was identified in 25 out of 27 cases (93%) compared with a background frequency of 10 out of 64 (16%; P = 5.49 × 10^−12). In summary, we report an outbreak of acute paediatric hepatitis associated with AAV2 infection (most likely acquired as a co-infection with human adenovirus that is usually required as a ‘helper virus’ to support AAV2 replication) and disease susceptibility related to HLA class II status. A case–control study investigating the causes of recent cases of acute hepatitis of unknown aetiology in 32 children identifies an association between adeno-associated virus infection and host genetics in disease susceptibility.
The increasing penetration of inverter-based resources (IBRs) is changing grid dynamics and challenging safe and reliable grid operation. Particularly, the increasing integration of IBRs may cause the small-signal stability issues resulting from the dynamic interaction between the IBR inverter controls and the power network in a power system with high penetration of IBRs. It is challenging for assessing the small-signal stability in such a power system due to the complex interaction between IBRs interconnected through the power network. The assessment complexity is further increased when considering variable IBR generation. To address the challenges, this paper proposes a method for small-signal stability analysis of a multi-IBR power system under uncertain renewable generation. First, we derive that the small-signal stability of a multi-IBR power system can be estimated based on the smallest eigenvalue of a weighted Laplacian matrix of the power network. Then, a robust optimization problem is formulated to analyze the small-signal stability of a multi-IBR power system under variable renewable generation. The efficacy of the proposed method is demonstrated on a power system with three IBRs by eigenvalue analysis and electromagnetic transient simulations.
The growing penetration of renewable resources such as wind and solar into the electric power grid through power electronic inverters is changing the grid dynamics and challenging grid protection. Due to the advanced inverter control algorithms, the inverter-based resources present fault responses different from conventional generators, which can fundamentally affect the way that the power grid is protected and thus is challenging grid protection engineers. This paper studies inverter dynamics during the system restoration period and their impact on protection schemes in a grid-connected solar photovoltaic (PV) system following grid disturbances. To this end, the solar PV system with a detailed inverter model that consider inverter switching dynamics along with inverter blocking and deblocking functions are constructed for the hardware-in-loop simulation based on a real-time digital simulator (RTDS). It is found that undesired transient events such as three-phase overvoltage and overcurrent as well as negative sequence current may occur after the inverter is deblocked to reinject energy into the system during the restoration period following a grid disturbance, especially when the system is under weak grid conditions. The undesired transient events may lead to misoperation of instantaneous overcurrent and negative sequence overcurrent protection schemes.
This paper explores the use of microgrids during cold-load pickup (CLPU) phenomena, which are typical after an outage in distribution networks with high share of ther-mostatically controlled load (TCL). We present a mixed-integer linear programming (MILP) formulation for scheduling service restoration (SR). The proposed model computes the optimal re-connection sequence, generation and storage levels for the microgrids as well as power supply level from the main grid. The model is tested on different modifications of the IEEE-13 feeder network. The proposed approach is suitable for practical SR scheduling and to test the CLPU capabilities of a distribution network during the planning process.
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