Spring Flood Forecasting Based on the WRF-TSRM Mode

The snowmelt process is becoming more complex in the context of global warming, and the current existing studies are not effective in using the short-term prediction model to drive the distributed hydrological model to predict snowmelt floods. In this study, we selected the Juntanghu Watershed in Hutubi County of China on the north slope of the Tianshan Mountains as the study area with which to verify the snowmelt flood prediction accuracy of the coupling model. The weather research and forecasting (WRF) model was used to drive a double-layer distributed snowmelt runoff model called the Tianshan Snowmelt Runoff Model (TSRM), which is based on multi-year field snowmelt observations. Moreover, the data from NASA’s moderate resolution imaging spectroradiometer (MODIS) was employed to validate the snow water equivalent during the snow-melting period. Results show that, based on the analysis of the flow lines in 2009 and 2010, the WRF-driven TSRM has an overall 80% of qualification ratios (QRs), with determination coefficients of 0.85 and 0.82 for the two years, respectively, which demonstrates the high accuracy of the model. However, due to the influence of the ablation of frozen soils, the forecasted flood peak is overestimated. This problem can be solved by an improvement to the modeled frozen soil layers. The conclusion reached in this study suggests that the WRF-driven TSRM can be used to forecast short-term snowmelt floods on the north slope of the Tianshan Mountains, which can effectively improve the local capacity for the forecasting and early warning of snowmelt floods

Heavy ion irradiation simulation of high dose irradiation induced radiation effects in materials

Materials used for ADS, ITER, fast reactor, etc suffer very high dose irradiations of protons and/or neutrons. The yearly accumulated irradiation doses could reach a couple of hundred dpa in ADS, ~40 dpa in fast reactors and ~30 dpa in ITER’s DEMO, producing severe radiation damage in materials and leading to a breakdown or accident of these installations. Investigation of such high dose irradiation induced radiation damage is a currently interesting topic with great importance. It is deeply hampered for lack of high dose neutron and proton sources. The heavy ion irradiation simulation technique has been developed at HI-13 tandem accelerator to investigate radiation damage encountered in the above mentioned installations. An experiment was carried out to verify the reliability and validity of heavy ion irradiation simulation. A series of experiments were performed by heavy ion irradiation simulation in combination with positron annihilation lifetime spectroscopy to investigate the temperature and dose dependence of radiation damage in stainless steels, tungsten, tantalum, etc. Some experimental results will be presented and discussed.Матеріали, що використовуються в ADS, ITER, швидкому реакторі, піддані високим дозам опромінення протонами та/або нейтронами. Це опромінення викликає серйозне радіаційне пошкодження матеріалів, що призводить до руйнування цих устаткувань або їх аварії. Дослідження радіаційних пошкоджень, зумовлених опроміненням великими дозами, є досить актуальним та важливим завданням. Однак це дослідження гальмується внаслідок відсутності нейтронних та протонних джерел, що мають високі щільності потоків часток. Моделювання з використанням опромінення важкими іонами представляє ефективний шлях такого дослідження. Метод моделювання з використанням опромінення важкими іонами на основі тандемного прискорювача НІ-13 застосовувався в Інституті атомної енергії Китаю для дослідження радіаційних пошкоджень, що спостерігаються у вищезазначених устаткуваннях. Перевірена надійність та достовірність моделювання за допомогою опромінення важкими іонами; виконано низку експериментів шляхом моделювання важкими іонами у поєднанні зі спектроскопією часу життя позитронів для вивчення залежності радіаційних пошкоджень від температури і дози для нержавіючих сталей, вольфраму, танталу і т.д. Представлені і обговорюються деякі експериментальні результати.Материалы, используемые в ADS, ITER, быстром реакторе, подвержены очень высоким дозам облучения протонами и/или нейтронами. Это облучение вызывает серьёзное радиационное повреждение материалов, что приводит к разрушению этих установок или их аварии. Исследование радиационных повреждений, вызванных облучением большими дозами, является весьма актуальной и важной задачей. Однако это исследование тормозится из-за отсутствия нейтронных и протонных источников, имеющих высокие плотности потока частиц. Моделирование с использованием облучения тяжелыми ионами предоставляет эффективный путь такого исследования. Метод моделирования с использованием облучения тяжелыми ионами на основе тандемного ускорителя НI-13 применялся в Институте атомной энергии Китая для исследования радиационных повреждений, встречающихся в вышеупомянутых установках. Проверена надежность и достоверность моделирования с помощью облучения тяжелыми ионами; выполнен ряд экспериментов путем моделирования облучения тяжелыми ионами в сочетании со спектроскопией времени жизни позитронов для изучения зависимости радиационных повреждений от температуры и дозы для нержавеющих сталей, вольфрама, тантала и т.д. Представлены и обсуждаются некоторые экспериментальные результаты

Case report: Surgical repair of congenitally corrected transposition of the great arteries with the guidance of three-dimensional printing

A 10-year-old girl presented with obvious cyanosis, and the saturation of arterial blood oxygen (SpO2) was decreased to 60.5% in the outpatient examination. Computed tomography angiography (CTA) and echocardiography suggested congenitally corrected transposition of the great arteries (ccTGAs), membranous ventricular septal aneurysm (MVSA), atrial septal defect (ASD), severe pulmonary stenosis (PS), and severe tricuspid regurgitation (TR). Due to the complex pathological anatomical structures, the three-dimensional printed model was used for preoperative assessment. After a comprehensive evaluation was completed, the operation was performed by physiological correction under cardiopulmonary bypass, including the resection of MVSA, repair using the bovine pericardial patch for ASD, and linear valvuloplasty of the tricuspid valve. Due to the special anatomical structures of ccTGA, PS was treated by extracardiac pipe technique. After the operation, the patient recovered well, cyanosis disappeared, SpO2 was up to 96%, and the extracardiac pipe was well-functioning without regurgitation or obstruction

Analysis of driving factors of water demand based on explainable artificial intelligence

Study region: Beijing–Tianjin–Hebei Region, China Study focus: Understanding factors driving water demand is crucial for water resource planning and management. However, traditional models fail to capture the complex nonlinear factors that drive real-world water demand. While machine learning models can capture nonlinear relationships, comprehending the complex mechanisms underpinning the models is difficult. Therefore, we combined machine learning with explainable artificial intelligence to analyze the factors driving water demand in the study region. New hydrological insights for the region: A water demand forecasting framework is proposed for analyzing the factors driving water demand. Results show that the main driving factors differ across city types. Population is the most crucial factor influencing water demand, with an effect size of 50.30%, 39.72%, and 31.79% in service-based, industrial, and agricultural cities, respectively. The second- and third-most important factors in service-based cities are the added value of secondary industry (AVSI) and irrigated area (IA), respectively. In industrial and agricultural cities, the second- and third-most-important factors are AVSI and temperature and temperature and IA, respectively. By quantifying the nonlinear relationships between water demand and driving factors, we identify the critical points associated with changes in correlation structure, such as urbanization rate (70%) and per capita disposable income (25,000 CNY per annum). Thus, this study can serve as a valuable reference for developing accurate models to forecast water demand

Impacts of Climate Changes on Water Resources in Yellow River Basin, China

AbstractThis study examined the impacts of future climate changes on water resources and extreme flows in Yellow River Basin (YRB), China, using the Coupled Land surface and Hydrology Model System (CLHMS) driven by the IPCC scenarios RCP 2.6, 4.5 and 8.5. First, the skill of 14 IPCC AR5 GCMS for simulating temporal and spatial temperature and precipitation in Yellow River Basin has been evaluated. Using the bias-corrected result of RCP storylines, the CLHMS model was developed to predict the 21 century climate and water cycle change. All the three simulation results indicate a reduction in water resources. The current situation of water shortage since 1980s will keep continue, the water resources reduction varies between 30 and 24% for RCP 2.6 and 4.5 scenarios. RCP 8.5 scenario simulation shows a decrease of water resources in the early and mid 21th century, but after 2080, with the increase of rainfall, the extreme flood events tends to increase

Rethinking water resources management from water-energy nexus perspective — a research and comparison of Jing-Jin-Ji Region of China and California of the United States

The relationship between water and energy is extremely close and complex, especially in water use system. However, the energy consumption of water systems has been ignored in water resources management due to the lack of deep understanding of the water-energy nexus. Based on analysis of waterrelated energy in water use, this paper selected Jing-Jin-Ji region of China and California of the United States to conduct a research study and found that the energy consumption of water use systems accounted for about 16% and 20% of the total electricity consumption of Jing-Jin-Ji region and California, respectively, water use has shifted more energy-intensive. This paper systematically quantified the urban water–energy relationship, analyzed the water supply structure and the energy efficiency and energy consumption in different water system sectors, and found that California’s total water use is 3.3 times that of Jing-Jin-Ji region, but the energy consumption of California’s water systems is only 2.3 times that of Jing-Jin-Ji region. This study suggests that water conservation is a cost-effective way to save energy, and it is necessary to quantitatively analyze the water-energy nexus for a more comprehensive and deep understanding of water resources management

Effect of Oxidation Time on the Structure and Corrosion Resistance of Micro-Arc Oxidation Coating of AZ91D Magnesium Alloy in (NH4)2ZrF6 Electrolyte System

Micro-arc oxidation (MAO) coatings were obtained from an AZ91D magnesium alloy at different oxidation times (5, 10, 15, and 20 min), using a zirconium salt electrolyte system, with (NH4)2ZrF6 as the main salt. The morphology of the coatings was studied using a scanning electron microscope (SEM) and confocal laser scanning microscopy (CLSM). Energy dispersive spectrometry (EDS), X-ray diffractometry (XRD), and X-ray photoelectron spectroscopy (XPS) were employed to determine the type of element and the composition of its phase. The potentiodynamic polarization curve (PDP) was applied to illustrate the corrosion resistance of the coatings. We found the coatings had minor porosity and the best compactness when the MAO treatment time was 10 min. The coatings mainly comprised MgO, ZrO2, MgF2, and Zr3O2F8 phases and amorphous magnesium phosphate. Among the MAO coatings prepared in this experiment, the 10 min coating had the lowest corrosion current density (Icorr), and the Icorr was 4.864 × 10−8 A/cm2, which was three orders of magnitude lower than the uncoated AZ91D magnesium alloy