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11.
《Contact lens & anterior eye》2022,45(3):101538
The disease of myopia has come into focus as a worldwide public health concern. Myopia has shown increasing prevalence, incidence at earlier age and progression to a higher degree. Progressive increase in degree of myopia is strongly associated with increase in axial length of the eye. Various interventions have been shown to slow axial elongation in children. These interventions have been studied to assess efficacy in slowing axial elongation and correction of vision. In addition, research into quality of vision, risk of adverse events, overall safety and impact on vision-related quality (VR-QoL) of life has been pursued. In contrast, studies have been published to demonstrate the risks of myopia, high myopia and increased axial length. This review will discuss VR-QoL assessment on the most effective and most commonly prescribed interventions to slow axial elongation and myopia progression. The patient attributes considered are VR-QoL scores from validated instruments. The development and use of validated survey instruments to assess the patient-reported outcomes is discussed. The review demonstrates that there are numerous factors that may impact VR-QoL to evaluate in the decision-making process when eye care providers consider when, how and if to prescribe myopia management (MM) for children with myopia. 相似文献
12.
《International Journal of Hydrogen Energy》2021,46(80):40001-40013
Accurate prognosis of limited durability is one of the key factors for the commercialization of proton exchange membrane fuel cell (PEMFC) on a large scale. Thanks to ignoring the structure of the PEMFC and simplifying the prognostic process, the data-driven prognostic approaches was the commonly used for predicting remaining useful life (RUL) at present. In this paper, the proposed cycle reservoir with jump (CRJ) model improves the ESN model, changes the connection mode of neurons in the reservoir and speeds up the linear fitting process. The experiment will verify the performance of CRJ model to predict stacks voltage under static current and quasi-dynamic current conditions. In addition, the reliability of the CRJ model is verified with different amount of data as the training and test sets. The experimental results demonstrate that the CRJ model can achieve better effect in the remaining useful life prognosis of fuel cells. 相似文献
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Andrej Lotrič Mihael Sekavčnik Igor Kuštrin Mitja Mori 《International Journal of Hydrogen Energy》2021,46(16):10143-10160
We present the results of a life-cycle assessment (LCA) for the manufacturing and end-of-life (EoL) phases of the following fuel-cell and hydrogen (FCH) technologies: alkaline water electrolyser (AWE), polymer-electrolyte-membrane water electrolyser (PEMWE), high-temperature (HT) and low-temperature (LT) polymer-electrolyte-membrane fuel cells (PEMFCs), together with the balance-of-plant components. New life-cycle inventories (LCIs), i.e., material inputs for the AWE, PEMWE and HT PEMFC are developed, whereas the existing LCI for the LT PEMFC is adopted from a previous EU-funded project. The LCA models for all four FCH technologies are created by modelling the manufacturing phase, followed by defining the EoL strategies and processes used and finally by assessing the effects of the EoL approach using environmental indicators. The effects are analysed with a stepwise approach, where the CML2001 assessment method is used to evaluate the environmental impacts. The results show that the environmental impacts of the manufacturing phase can be substantially reduced by using the proposed EoL strategies (i.e., recycled materials being used in the manufacturing phase and replacing some of the virgin materials). To point out the importance of critical materials (in this case, the platinum-group metals or PGMs) and their recycling strategies, further analyses were made. By comparing the EoL phase with and without the recycling of PGMs, an increase in the environmental impacts is observed, which is much greater in the case of both fuel-cell systems, because they contain a larger quantity of PGMs. 相似文献
15.
Mohammadali Kiehbadroudinezhad Ali Rajabipour Michael Cada Majid Khanali 《国际能源研究杂志》2021,45(1):429-452
People in the Middle East are facing the problem of freshwater shortages. This problem is more intense for a remote region, which has no access to the power grid. The use of seawater desalination technology integrated with the generated energy unit by renewable energy sources could help overcome this problem. In this study, we refer a seawater reverse osmosis desalination (SWROD) plant with a capacity of 1.5 m3/h used on Larak Island, Iran. Moreover, for producing fresh water and meet the load demand of the SWROD plant, three different stand‐alone hybrid renewable energy systems (SAHRES), namely wind turbine (WT)/photovoltaic (PV)/battery bank storage (BBS), PV/BBS, and WT/BBS are modeled and investigated. The optimization problem was coded in MATLAB software. Furthermore, the optimized results were obtained by the division algorithm (DA). The DA has been developed to solve the sizing problem of three SAHRES configurations by considering the object function's constraints. These results show that this improved algorithm has been simpler, more precise, faster, and more flexible than a genetic algorithm (GA) in solving problems. Moreover, the minimum total life cycle cost (TLCC = 243 763$), with minimum loss of power supply probability (LPSP = 0%) and maximum reliability, was related to the WT/PV/BBS configuration. WT/PV/BBS is also the best configuration to use less battery as a backup unit (69 units). The batteries in this configuration have a longer life cycle (maximum average of annual battery charge level) than two other configurations (93.86%). Moreover, the optimized results have shown that utilizing the configuration of WT/PV/BBS could lead to attaining a cost‐effective and green (without environmental pollution) SAHRES, with high reliability for remote areas, with appropriate potential of wind and solar irradiance. 相似文献
16.
Shuai Zhang Juan Li Teng An Shuqi Zheng Ke Yang Liang Lv Chuang Xie Liqiang Chen Lin Zhang 《International Journal of Hydrogen Energy》2021,46(39):20621-20629
In this work, we investigate the influence mechanism of hydrogen partial pressure on fracture toughness and fatigue life of a high strength pipeline steel. Both fracture toughness test and fatigue life test are carried out under different hydrogen partial pressure. The experimental results show that with the increasing of hydrogen partial pressure, fracture toughness and fatigue life decrease and the decrease trends gradually flatten out. Hydrogen has a larger effect on fatigue life than fracture toughness. Only 3% hydrogen gas can cause a 67.7% decrease of fatigue life. The in-situ hydrogen permeation test is performed respectively in 2 MPa, 5 MPa and 8 MPa hydrogen partial pressure. With the increasing of hydrogen partial pressure, the increase trend of hydrogen permeation current gradually tends to be gentle, which indicates that the hydrogen atoms entering into the material gradually become saturated. This result can be used to clarify the influence mechanism of hydrogen partial pressure on fracture toughness and fatigue life. 相似文献
17.
Mariusz Banaszkiewicz 《Materials at High Temperatures》2019,36(4):354-367
The principal objective of work was to develop fast and accurate method for online creep life monitoring of steam turbine rotors. For this purpose, a characteristic strain model of creep was investigated and validated using test data of 2%CrMoV rotor steel. The model was then used to determine creep damage functions which are introduced to compute creep damage at a constant temperature based on the Robinson time fraction rule. Finite element (FE) creep calculations of a turbine rotor were performed using the same creep model to obtain reference damage results for validating the proposed method. Comparisons of the results obtained using both methods showed a very good accuracy of the online creep damage predictions. 相似文献
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Carolina Blanco Raúl Bodas Sonia Andrés Jose María Rodríguez-Calleja Javier Mateo Fernando Rozada F. Javier Giráldez 《International Journal of Food Science & Technology》2020,55(3):1119-1125
Thirty-two lambs were finished on a total mixed ration (TMR) pelleted alone (00SS) or including sunflower soap stock (SS): 15SS (15 g SS per kg TMR), 30SS (30 g SS per kg TMR) and 60SS (60 g SS per kg TMR). Lambs (8 per group) were slaughtered at 27 kg live weight. Colour evolution, lipid oxidation, microbial growth and detection of diarrhoeagenic Escherichia coli were studied in meat samples. SS in the diet reduced meat lipid oxidation (P < 0.05), but had no significant effect (P > 0.05) on the cholesterol oxidation products. Meat from 60SS and control animals (00SS) revealed greater discoloration (P < 0.05) than 15SS. SS supplementation did not affect the microbiological populations, whereas high doses of SS seemed to increase the proliferation of diarrhoeagenic E. coli on day 14 (P < 0.10). These results suggest that the rate of SS inclusion in the diet of fattening lambs should not be above 15 g SS per kg TMR. 相似文献
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