Deep learning (DL) and the collocation method are merged and used to solve partial differential equations (PDEs) describing structures' deformation. We have considered different types of materials: linear elasticity, hyperelasticity (neo‐Hookean) with large deformation, and von Mises plasticity with isotropic and kinematic hardening. The performance of this deep collocation method (DCM) depends on the architecture of the neural network and the corresponding hyperparameters. The presented DCM is meshfree and avoids any spatial discretization, which is usually needed for the finite element method (FEM). We show that the DCM can capture the response qualitatively and quantitatively, without the need for any data generation using other numerical methods such as the FEM. Data generation usually is the main bottleneck in most data‐driven models. The DL model is trained to learn the model's parameters yielding accurate approximate solutions. Once the model is properly trained, solutions can be obtained almost instantly at any point in the domain, given its spatial coordinates. Therefore, the DCM is potentially a promising standalone technique to solve PDEs involved in the deformation of materials and structural systems as well as other physical phenomena.
O artigo analisa textos de estudantes do setimo ano, do Ensino Fundamental de uma escola publica do campo, de Barreiras – BA. Nessa analise, consideramos o contexto social, economico e cultural a que pertencem esses estudantes. Metodologicamente, trabalhamos etnografia de sala de aula, realizando: observacao, descricao e analise, e participacao colaborativa, com a aplicacao de sequencia didatica, e o uso do texto biografico, subsidiando a producao do texto autobiografico. A luz da teoria dos letramentos multiplos e da leitura sociolinguistica, foi possivel reconhecer a necessidade da observacao do lugar de pertenca do estudante no/do campo e suas distintas praticas de conhecimento de leitura e de escrita, bem como a importância da valorizacao dessa cultura no contexto escolar. Encontramos nos textos escritos, evidentes demarcacoes dos fatores socioculturais de seu autor, com multiplas expressoes e marcas linguisticas que identificam o lugar de pertencimento que, em certos casos, nao sao compreendidas em sala de aula.
Abstract This paper specifies and compares the ancillary services used by transmission system operators in selected countries within ENTSO-E (European Network of Transmission System Operators-Electricity) for operational needs of their transmission systems. The comparison of the ancillary services’ unit prices is also given. In addition, analyses of various experiences gained by ENTSO-E countries within their electric power systems in relation to initiatives supporting the power generation from renewable energy sources (RES) and the methods of their integration into the electric power system were made. Namely, depending on the total amount of RES, depending on the incentive system for electricity production from RES and the development of an organized electricity market, different balancing responsibility models for electricity producers from RES were established.
Abstract Line surge arresters are mainly used for transmission line lightning performance improvement. Calculation of energy stresses of lines surge arrester is of extreme importance for the selection of the arrester class. Energy stresses of transmission line surge arresters due to multicomponent lightning flashes are analysed in this paper. To obtain lightning data two approaches were used: direct measurements using instrumented towers and lightning location systems. Both lightning monitoring systems are described. Data obtained from lightning monitoring systems are compared and used in simulations. Detailed modelling procedure for a transient analysis of the transmission lines is also described. Multicomponent lightning flash and 110 kV transmission line were modelled using Electromagnetic Transient Program -Restructured Version (EMTP – RV). The arrester current shapes and arrester energy duties are presented in order to clearly show influence of lightning current parameters to arrester energy duty.
Abstract The paper consists of three parts. In the introduction and the first part of this paper are given basic theoretical considerations on possible ways for treatment of the neutral point in distribution grids with special reference to the method of neutral grounding of distribution transformers through a low ohmic resistor and a compensation coil. The second part gives the use analysis of a low ohmic resistor and a compensation coil as the future choice of neutral point grounding on the particular distribution grid powered by a substation TS 35/10 kV. In the third part of the paper, the results were obtained using an adequate dynamic distribution model, using the EMTP-ATP software package. Also, in this part, calculations are made for neutral grounding through a low ohmic resistor, a compensation coil, as well as in the case of isolated grids, and a comparison of the obtained values of the overvoltage coefficients.
Objectives Demarcated opacities (DO) on teeth affected by Molar Incisor Hypomineralisation (MIH) were observed to investigate if parameters of DO existence and the number of teeth affected could be used to predict the progression of disease. Material and methods In 2009, the MIH prevalence was 11.5% (n=51) among 446 subjects in Sarajevo, aged from 6 to 9 years. In subjects with MIH who gave consent for further participation (n=25), the teeth with DO were observed after a 12-month period. Results our sample included 29 permanent incisors and 14 first permanent molars with DO. The number of teeth with light opacities was significantly higher than the number of teeth with dark opacities. Opacities were more numerous on surfaces which were not exposed to masticatory pressure. The size of tooth surface affected by DO occurrence ranged from 1.33% to 56.56%. The number of affected teeth ranged from two to six. A strong positive correlation between MIH progression and dark colored opacities located on the occlusal/incisal surface of teeth was noted. Larger part of tooth surface was affected by hypomineralisation in the case of dark-colored opacities. The DO presence on incisors was more likely to be located on vestibular surfaces and on the first permanent molars on their occlusal surfaces. Conclusions The color of DO occurrence was the best predictor for MIH progression both independently and in combination with the number of affected teeth. Location of DO occurrence was a good independent predictor for MIH progression. It is important to collect information about color and location of DO presence.
Introduction: A promising strategy that can lead to longer brain cell survival after an acute stroke is therapeutic hypothermia. It represents a controlled decrease in body temperature for therapeutic reasons. It is increasingly represented as a therapeutic option and is one of the most challenging treatments that improves neurological recovery and treatment outcome in patients with acute stroke. Aim: To examine the effect of therapeutic hypothermia on liver enzymes in patients with diagnosis of stroke. Methods: A total of 101 patients diagnosed with acute stroke were treated. The first group (n=40) were treated with conventional treatment and therapeutic hypothermia, while the second group (n=61) only with conventional treatment. Cooling of the body to a target body temperature of 34°C to 35°C was performed for up to 24 hours. Outcome (survival or death) of treatment was monitored, degree of disability was determined by National Institutes of Health Stroke Scale (NIHSS) and assessment of consciousness using the Glasgow Coma Scale (GCS). Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) values were taken at admission, after 24 hours, and were monitored upon discharge. Results: There was a significant difference in AST values at admission relative to disease outcome (p = 0.002), as well as for ALT (p = 0.008). In patients treated with therapeutic hypothermia, mean AST values decreased after 24 hours (32.50 to 31.00 IU/mL) as well as ALT values (27.50 to 26.50 IU/mL), without statistical significance. In the group of subjects who survived with sequela, AST values correlated with GCS (rho = -0.489; p = 0.002) and NIHSS (rho = 0.492; p = 0.003), ALT values correlated with GCS (rho = -0.356; p = 0.03) but not with NIHSS. Conclusion: AST and ALT values at admission correlate with the severity of the clinical picture. Therapeutic hypothermia is hepatoprotective and lowers AST and ALT values.
Abstract The most commonly farmed fish species in Bosnia and Herzegovina’s aquaculture are from the family Salmonidae, including brook trout Salvelinus fontinalis which is reared both for consumption and stocking purposes. A number of farmers complained about the elevated frequency of anatomical deformities in the smolts and fingerlings of brook trout, decreasing their fitness rate and causing significant financial loss. Since it has been shown that occurrence of deformities is correlated with the low genetic diversity and high inbreeding, this study aimed to assess intra- and interpopulation diversity of Salvelinus fontinalis from different freshwater fish farms in Bosnia and Herzegovina by observing variation in mitochondrial and nuclear genome. Total of 109 samples of brook trout from three hatcheries located at the Neretva River were analyzed for the mitochondrial control region and seven nuclear microsatellite loci. Both PCR-RFLP and sequencing revealed only one haplotype of the control region in all investigated trout. Overall, a low number of genotypes was evident across all the observed loci. Values of genetic diversity and polymorphic information content followed the increase in the number of alleles per locus. In general, values of inbreeding coefficient were generally very high, while the genetic diversity and observed heterozygosity had low rates. The results of our study are congruent with the findings of previous studies in which developmental deformities were concomitant with the low genetic diversity and inbreeding depression. It is, therefore, strongly advised to regularly supplement the broodstock with new, unrelated individuals, as it is of vital importance for sustaining a satisfying level of genetic diversity and preventing inbreeding depression. Additionally, maintaining good management practices regarding the fluctuation of water temperature, exposure to pollution, nutrition, etc., will further contribute to the prevention of this detrimental condition.
Abstract The aim of this paper is to explore the potential link between gross capital formation and CO2 emissions by using the Toda and Yamamoto approach. The annual time-series data were collected for the period 1971-2014. Due to the fact that Kuwait aims to become a major trading hub by 2035, it has made significant efforts to improve the infrastructure. Moreover, Turkey is also making strong efforts to improve the manufacturing sector as well as infrastructure, and represents an important trading hub that links Europe with the Middle East. Thus, Turkey and Kuwait are expected to strengthen their economic ties and expand trade, which was the motivation for comparing the link of interest in these two countries. The study’s findings confirm the bidirectional links between all of the variables of interest not only in the case of Turkey but also in the case of Kuwait, suggesting some important policy implications.
Multimodality of input in incidental L2 vocabulary learning has recently been a topic of interest among language acquisition researchers, yet the results have been somewhat contradictory. This study seeks to compare the impacts of two different multimodalities on incidental L2 vocabulary learning, namely, reading-plus-watching (experimental group I) vs. reading-plus-listening (experimental group II), as compared to the reading only condition, which is included as a control measure. Experimental group I watched and read the transcriptions of four news texts with electronic glosses for the target words, while experimental group II read and listened to the same news texts again with electronic glosses for the same 20 target words. Next, the two experimental groups swapped roles with a new set of four news texts glossed for another group of 20 target words. The control group only read the same eight news texts without glosses. The results suggest that reading-plus-listening can be a more conducive multimodal presentation for incidental vocabulary learning as compared to reading-plus-watching. The results also challenge the validity of some principles of the Cognitive Theory of Multimedia Learning in incidental L2 vocabulary learning, while providing supporting evidence for some other principles.
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