Joint Optimization of Operation and Maintenance Policies for Solar-Powered Microgrids

In a solar-powered microgrid (MG), the optimal maintenance strategy is influenced by the downtime cost of the photovoltaic (PV) system, which in turn depends on the operation PV within the MG network. Also, the dispatch policy used in the MG will influence the economic feasibility of maintenance plans. In this paper, we present an approach for optimizing the operation and maintenance policy jointly for a solar-powered MG considering the dependence between the two policies. The two-layered approach presented in this paper seeks to unify the practicality of simulation and the efficiency of analytical models. In the upper layer, we optimize the operation of MG by solving the optimal power dispatch within the MG network using linear programming approach. Then, we calculate the penalty costs under the aging conditions of PV systems. In the bottom layer, by incorporating the penalty costs as input parameters, we use a continuous-time Markov chain model to calculate the optimal maintenance policy for the PV system. The proposed approach could be used in the stipulation process between MG owner and PV system maintenance provider to minimize the money waste on both sides.This research was partly funded by the EPSRC/Innovate UK Centre for Smart Infrastructure and Construction (EP/N021614/1) and also supported by Sustain-Owner (Sustainable Design and Management of Industrial Assets through Total Value and Cost of Ownership), a project sponsored by the EU Framework Programme Horizon 2020, MSCA-RISE-2014: Marie Skodowska-Curie Research and Innovation Staff Exchange (Rise) (grant agreement number 645733 Sustain-owner H2020-MSCA-RISE-2014)

An Investigation into Enterobacteriaceae Responsible for Early Mortality in Japanese Quail Chicks and Their Antibiotic Susceptibility Patterns

Quail is an alternative source of protein for humans. These birds can be affected by common bacterial infections. Bacterial contamination of egg is the most common cause of mortality in Japanese quail chicks. In order to study the role of some members of Enterobacteriaceae responsible for early mortality in Japanese quail chicks, 100 dead or moribund quail chicks were obtained from 10 different farms in Ahvaz, Iran. Samples were taken from the liver and yolk sac of the birds and bacterial isolation from samples was conducted by streaking them on MacConkey, Brilliant Green, Salmonella-Shigella and Xylose Lysine Deoxycholate agar plates. The plates were incubated at 37 °C for 24-48 hours, and by standard biochemical tests bacterial isolates were identified. Final confirmation of Salmonella serotypes was performed by Razi Institute. All the isolates were examined for susceptibility to 12 different antibiotics (Padtan-Teb Co., Tehran, Iran) by the disk diffusion (Kirby Bauer) method. The results showed that 78% of the quail chicks were infected. The isolated bacteria were Escherichia coli (44%), Klebsiella pneumonia (8%), Salmonella serovar ruzizi (5%), Salmonella serovar typhimurium (3%), Enterobacter cloacae (4%), Enterobacter aerogenes (4%), Proteus vulgaris (5%) and Proteus mirabilis (5%). One hundred percent susceptibility was observed to gentamycin, soltrim, tetracycline, fosfomycin, florfenicol, cephalexin and ceftriaxone. E. coli isolates were susceptible to soltrim and ceftriaxone, Salmonella isolates were susceptible to fosfomycin, Enterobacter isolates were susceptible to ceftriaxone and Proteus and Klebsiella isolates showed susceptibility to ceftriaxone. It is concluded that the members of Enterobacteriaceae family, specifically the genera Escherichia and Salmonella, are the major causes of early mortality in newly-hatched Japanese quail chicks

Municipal solid waste management during COVID-19 pandemic: a comparison between the current activities and guidelines

The COVID-19 pandemic has affected everyone�s lifestyle and this has resulted in a change in the quantity and composition of municipal solid wastes. Moreover, the post-pandemic waste management is very important as a bad management may lead to the more spread of the disease. The objective of this study was to evaluate the application of guidelines presented for the era of the COVID-19 pandemic in proper solid waste management. To this end, the data were collected by using interviews and field researches and then the obtained data were compared with the international guidelines presented by international organizations. By investigating the municipal waste management during this pandemic and its changes compared to pre-COVID-19, coordination of the plans with the guidelines was investigated. The activities of storage, collection, transportation, recycling, final landfill, as well as the observation of the health instructions by staff and informal sections were assessed in the current research. Although the results showed that the situation was satisfactory in the sections like health and safety of waste management operators due to the existence of protocols and general educations, the waste management plans have not been changed much from before the epidemic of the Coronavirus. The absence of a national policy and plan for waste management in the era of a pandemic and ignoring the guidelines developed by other countries and organizations were observable. Therefore, the codification of new policies for municipal waste management during an epidemic is necessary. © 2021, Springer Nature Switzerland AG

Lie symmetry and μ-symmetry methods for nonlinear generalized Camassa–Holm equation

Abstract In this paper, a Lie symmetry method is used for the nonlinear generalized Camassa–Holm equation and as a result reduction of the order and computing the conservation laws are presented. Furthermore, μ-symmetry and μ-conservation laws of the generalized Camassa–Holm equation are obtained

Effect of cold start on engine performance and emissions from diesel engines using IMO-Compliant distillate fuels

© 2019 Elsevier Ltd Emissions from ships at berth are small compared to the total ship emissions; however, they are one of the main contributors to pollutants in the air of densely-populated areas, consequently heavily affecting public health. This is due to auxiliary marine engines being used to generate electric power and steam for heating and providing services. The present study has been conducted on an engine representative of a marine auxiliary, which was a heavy duty, six-cylinder, turbocharged and after-cooled engine with a high pressure common rail injection system. Engine performance and emission characterisations during cold start are the focus of this paper, since cold start is significantly influential. Three tested fuels were used, including the reference diesel and two IMO (International Maritime Organization) compliant spiked fuels. The research engine was operated at a constant speed and 25% load condition after 12 h cooled soak. Results show that during cold start, significant heat generated from combustion is used to heat the engine block, coolant and lubricant. During the first minute, compared to the second minute, emissions of particle number (PN), carbon monoxide (CO), particulate matter (PM), and nitrogen oxides (NOx) were approximately 10, 4, 2 and 1.5 times higher, respectively. The engine control unit (ECU) plays a vital role in reducing engine emissions by changing the engine injection strategy based on the engine coolant temperature. IMO-compliant fuels, which were higher viscosity fuels associated with high sulphur content, resulted in an engine emission increase during cold start. It should be taken into account that auxiliary marine diesel engines, working at partial load conditions during cold start, contribute considerably to emissions in coastal areas. It demonstrates a need to implement practical measures, such as engine pre-heating, to obtain both environmental and public health advantages in coastal areas

Two-Scale Kirchhoff Theory: Comparison of Experimental Observations With Theoretical Prediction

We introduce a non-perturbative two scale Kirchhoff theory, in the context of light scattering by a rough surface. This is a two scale theory which considers the roughness both in the wavelength scale (small scale) and in the scales much larger than the wavelength of the incident light (large scale). The theory can precisely explain the small peaks which appear at certain scattering angles. These peaks can not be explained by one scale theories. The theory was assessed by calculating the light scattering profiles using the Atomic Force Microscope (AFM) images, as well as surface profilometer scans of a rough surface, and comparing the results with experiments. The theory is in good agreement with the experimental results.Comment: 6 pages, 8 figure

Markov Properties of Electrical Discharge Current Fluctuations in Plasma

Using the Markovian method, we study the stochastic nature of electrical discharge current fluctuations in the Helium plasma. Sinusoidal trends are extracted from the data set by the Fourier-Detrended Fluctuation analysis and consequently cleaned data is retrieved. We determine the Markov time scale of the detrended data set by using likelihood analysis. We also estimate the Kramers-Moyal's coefficients of the discharge current fluctuations and derive the corresponding Fokker-Planck equation. In addition, the obtained Langevin equation enables us to reconstruct discharge time series with similar statistical properties compared with the observed in the experiment. We also provide an exact decomposition of temporal correlation function by using Kramers-Moyal's coefficients. We show that for the stationary time series, the two point temporal correlation function has an exponential decaying behavior with a characteristic correlation time scale. Our results confirm that, there is no definite relation between correlation and Markov time scales. However both of them behave as monotonic increasing function of discharge current intensity. Finally to complete our analysis, the multifractal behavior of reconstructed time series using its Keramers-Moyal's coefficients and original data set are investigated. Extended self similarity analysis demonstrates that fluctuations in our experimental setup deviates from Kolmogorov (K41) theory for fully developed turbulence regime.Comment: 25 pages, 9 figures and 4 tables. V3: Added comments, references, figures and major correction

Human closed and open apex premolar teeth express different toll-like receptor

Background: The innate immune activation which promotes inflammation responses in the dental pulp tissue leads to the progression of dentin caries. Accordingly, toll-like receptors (TLRs) are key molecules of the innate immune system that identify pathogen-associated molecular patterns (PAMPs) on microorganisms and may have a critical role in a dental injury. Therefore, this study aimed to investigate the expression of TLR2, TLR3, and TLR4 in the human dental pulp of opened and closed apex teeth. Methods: Human dental pulps were derived from the healthy opened and closed apex premolar, in which extraction was indicated for orthodontic reasons. The extraction of RNA was performed and the gene expression determined by real-time polymerase chain reaction (RT-PCR). The result from real-time PCR was confirmed using western blot analysis. Results: Real-time PCR data analysis showed that the expression TLR2 and TLR4 were significantly increased in closed apex premolar teeth compared to open apex teeth, whereas TLR3 expression was not significantly different in these two groups (p <.05). Conclusion: The results of the present study suggested increased expression of TLR2 and TLR4 by the maturation of the apex, which may be due to the presence of microorganisms in the normal or destructed dental pulp tissue. Thus, identifying the expression of TLRs molecules in dental pulp tissue helps to develop a deeper knowledge of the immune responses in the oral cavity. © 2020 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals LL

An analysis of material consumption culture in the Muslim world

In this paper, we examine the notion of material consumption culture in Islamic societies. We differentiate between institutionalised religion and religion as culture. We contest the Orientalist portrayal of Islam as a fanatic ideology opposed to Western Modernity’s features of secularism, individualism, and pluralism. With reference to the Qur’anic text, we discuss that such qualities are embedded with Islam. We do not interpret the Qur’an from a theological perspective; rather, we seek to demonstrate the possibilities of its multiple interpretations. We argue that, in their everyday life consumption practices, Muslims (re)interpret religious guidelines in different ways and refer to Islam, as a transcendental set of guidelines, to make better sense of their cultural practices in different ways. We summarise our discussion by highlighting the importance of analysing the culture of consumption from the lens of insiders and offer directions for future research

Effects of cognitive behavioral therapy for insomnia (CBT-I) on quality of life: a systematic review and meta-analysis

The effects of cognitive behavioral therapy for insomnia (CBT-I) have consistently been shown to improve insomnia symptoms and other health-related outcomes, but the effects on QoL have been inconsistent. Many factors including the type CBT-I delivery and type of instrument used to assess QoL make the topic complex. The present systematic review and meta-analysis synthesized the evidence of CBT-I efficacy on QoL outcomes across different populations, delivery modes, and methodological aspects. Following the guidelines on preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), a literature search was conducted through PubMed, Web of Science, Scopus, and PsycINFO using keywords from relevant MeSH terms based on PICOS (Participants, Intervention, Comparison, Outcome and Study) criteria. Clinical trials investigating the effect of CBT-I as an intervention on QoL with any kind of control group were eligible if they reported mean scores and variation of QoL. Meta-analysis using a random-effect model was conducted to calculate the standardized mean differences (SMDs) in a set including all identified studies, as well as in three sub-sets: face-to-face CBT-I using randomized controlled trials (RCTs), online CBT-I using RCTs, and one-group pre- and post-treatment design. A total of 24 studies comprising 1977 participants (808 in an intervention group) from 12 countries were eligible for meta-analysis. The overall pooled estimate of SMD of QoL when all 24 studies were included was 0.47 (95% CI: 0.22; 0.72; I2 = 84.5%; tau2 = 0.31; p < 0.001). The overall pooled estimate of SMD of QoL was 0.46 (95% CI: 0.01–0.90; I2 = 87.5%; tau2 = 0.48, p < 0.001) for intervention groups with face-to-face CBT-I compared to controls; 0.47 (95% CI: 0.02–0.92; I2 = 88.3%; tau2 = 0.36; p = 0.04) for intervention groups with digital CBT-I compared to controls, and 0.46 (95% CI: 0.12–0.80; I2 = 52.9%; tau2 = 0.07; p = 0.08) for one-group pre- and post-comparison using CBT-I intervention compared to baseline. Moreover, effects of CBT-I on QoL were different across populations (pooled SMD = 0.59 for patients with insomnia; 0.29 for patients with insomnia comorbid with another major disorder; and 0.48 for other conditions) and types of QoL instruments (pooled SMD = 0.36 for disease-specific QoL instrument not on insomnia, 0.43 for generic QoL instrument, and 0.67 for a single-QoL-item instrument). The probability of publication bias was ruled out in overall and design specific sub-group analysis based on funnel plot and Egger's test. In conclusion, this meta-analysis confirmed a moderate, overall effect of CBT-I in improving QoL. However, due to small power and heterogeneity, future studies are needed to better explore the impact of moderating factors such as mode of delivery and type of QoL measure for assessment used