mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Architecture design and demand analysis on application layer of standard system for ubiquitous power Internet of Things

The ubiquitous power Internet of Things (UPIoT) is an intelligent service system with comprehensive state perception, efficient processing, and flexible application of information. It focuses on each link of the power system and makes full use of the mobile internet, artificial intelligence, and other advanced information and communication technologies in order to realize the inter-human interaction of all things in all links of the power system. This article systematically presents to the national and international organizations and agencies in charge of UPIoT layer standardization the status quo of the research on the Internet of Things (IoT)-related industry standards system. It briefly describes the generic standard classification methods, layered architecture, conceptual model, and system tables in the UPIoT application layer. Based on the principles of inheritance, innovation, and practicability, this study divides the application layer into customer service, power grid operation, integrated energy, and enterprise operation, emerging business and analyzes the standard requirements of these five fields. This study also proposes a standard plan. Finally, it summarizes the research report and provides suggestions for a follow-up work.
Steady-state voltage-control method considering large-scale wind-power transmission using half-wavelength transmission lines

Half-wavelength transmission can transmit large-scale renewable energy over very long distances. This paper proposes an improved steady-state voltage-control method for half-wavelength transmission systems considering largescale wind-power transmission. First, the unique voltage characteristics of half-wavelength lines are deduced based on the distributed parameter model. In the secondary voltage-control level, reactive power-transmission limits of half-wavelength lines are introduced as another control objective except for tracing the pilot bus voltage reference. Considering the uncertainty and fluctuation of wind power, the overvoltage risk-assessment method of half-wavelength lines is presented to determine specific voltage-control strategies. Simulation results demonstrate that the proposed voltage-control method delivers superior tracking performance according to a voltage reference value and prevents the overvoltage risk of halfwavelength lines effectively in different wind-power penetrations.
Power source-power grid coordinated typhoon defense strategy based on multiagent dynamic game theory

A power source-power grid coordinated typhoon defense strategy is proposed in this study to minimize the cost of power grid anti-typhoon reinforcement measures and improve defense efficiency. It is based on multiagent dynamic game theory. This strategy regards a typhoon as a rational gamer that always causes the greatest damage. Together with the grid planner and black start unit (BSU) planner, it forms a multiagent defense-attack-defense dynamic game model naturally. The model is adopted to determine the optimal reinforcements for the transmission lines, black start power capacity, and location. Typhoon Hato, which struck a partial coastal area in Guangdong province in China in 2017, was adopted to formulate a step-by-step model of a typhoon attacking coastal area power systems. The results were substituted into the multiagent defense-attack-defense dynamic game model to obtain the optimal transmission line reinforcement positions, as well as optimal BSU capacity and geographic positions. An effective typhoon defense strategy and minimum load shedding were achieved, demonstrating the feasibility and correctness of the proposed strategy. The related theories and methods of this study have positive significance for the prevention of uncertain large-scale natural disasters.
Generation expansion planning considering efficient linear EENS formulation

Power system equipment outages are one of the most important factors affecting the reliability and economy of power systems. It is crucial to consider the reliability of the planning problems. In this paper, a generation expansion planning (GEP) model is proposed, in which the candidate generating units and energy storage systems (ESSs) are simultaneously planned by minimizing the cost incurred on investment, operation, reserve, and reliability. The reliability cost is computed by multiplying the value of lost load (VOLL) with the expected energy not supplied (EENS), and this model makes a compromise between economy and reliability. Because the computation of EENS makes the major computation impediment of the entire model, a new efficient linear EENS formulation is proposed and applied in a multi-step GEP model. By doing so, the computation efficiency is significantly improved, and the solution accuracy is still desirable. The proposed GEP model is illustrated using the IEEE-RTS system to validate the effectiveness and superiority of the new model.
Lenalidomide downregulates ACE2 protein abundance to alleviate infection by SARS-CoV-2 spike protein conditioned pseudoviruses

Dear Editor, The recent health emergency caused by SARS-CoV-2 created a global pandemic. Similar to other CoVs, SARS-CoV-2 utilizes its Spike (S) protein to specifically recognize the human angiotensin converting enzyme 2 (ACE2) membrane receptor for infection. Thus, blocking SARS-CoV-2-S/ACE2 interactions has been investigated as a therapeutic direction in treating SARS-CoV-2, including recombinant hACE2 proteins, ACE2-derived peptides, neutralizing antibodies, engineered ACE2 traps, various heparins, TMPRSS2 inhibitors, and others. Deep mutagenesis assays identified engineered ACE2 mutants with enhanced binding affinity with SARS-CoV-2-S proteins, facilitating development of approaches targeting SARS-CoV-2 S protein binding to ACE2. ACE2 is a plasma membrane attached enzyme converting angiotensin II into angiotensin (1-7) that lowers blood pressure. ACE2 is broadly expressed but detectable expression is enriched in alveolar cells, enterocytes, arterial, and venous endothelial cells. The E3 ligase MDM2 was reported to target ACE2 for degradation in an AMPK phosphorylation-dependent manner. Intriguingly, increased ACE2 levels were observed in lungs from patients with comorbidities associated with severe COVID-19. Modulating ACE2 protein homeostasis is an attractive direction to prevent/control SARS-CoV-2 infection;however, regulatory mechanisms of ACE2 protein control remain elusive.
Organized Warm-Sector Rainfall in the Coastal Region of South China in an Anticyclone Synoptic Situation: Observational Analysis

Organized warm-sector rainfall (OWSR) near the coast of South China tends to occur in certain synoptic situations characterized with either a low-level jet or an anticyclone, with the latter being less investigated. This paper fills the gap by analyzing 15 OWSR events that occurred in an anticyclone synoptic situation during the pre-summer rainy season of 2011-2016, based on high-resolution observational and reanalysis data. The results show that the anticyclone synoptic situation produces marked northerly boundary-layer winds inland and obvious northeasterly, easterly/southwesterly, and southeasterly boundary-layer winds near the coasts of eastern Guangdong, western Guangdong, and Guangxi, respectively. The coastal boundary-layer winds promote favorable environmental conditions and strong convergence for convection initiation; consequently, OWSR is prone to occur near the coasts of western Guangdong and Guangxi, but exhibits different formation and propagation features in the following two subareas. (1) The southeasterly boundary-layer winds tend to converge near the border area between Guangxi and Guangdong (BGG), promoting the formation of a stable convective line along the mountains. The convective line persists with support of upper-level southwesterly winds that facilitate convective cells to propagate along the convective line, producing heavy OWSR along the mountains near BGG. (2) In contrast, a west-east convective line tends to form and maintain near the coast of Yangjiang (YJ) area, about 200 km east of BGG, owing to stable convergence between the easterly (or southwesterly) and the northerly boundary-layer winds reinforced by the mountains near YJ. Moreover, the coupling of upper-level westerly winds with the easterly (southwesterly) boundary-layer winds facilitates expansion (eastward propagation) of the convective line, causing west-east-oriented heavy OWSR near the coast of YJ. In a word, this study reveals refined properties of OWSR initiation and development in the anticyclone synoptic situation, which may help improve the forecast skill of OWSR during the pre-summer rainy season in South China.
Wall-resolved large-eddy simulation of turbulent channel flows with rough walls

Turbulent flows over rough surfaces widely exist in nature and industry.Investigating its mechanism is of theoretical and practical significance.In this work we simulate the turbulent channel flow with rough walls using large-eddy simulation with rough elements resolved using the curvilinear immersed boundary method and compare the results obtained in this work with those in the paper by Yuan and Piomelli (J.Fluid Mech.,vol.760,pp.R1,2014),where the volume of fluid method was employed for modeling rough elements.The mean streamwise velocity profiles predicted by the two methods agree well with each other.Differences in Reynolds stresses and dispersive stresses are observed,which are attributed to the different approaches in dealing with the complex geometry of the rough surface.
Centrifuge model test on performance of thermosyphon cooled sandbags stabilizing warm oil pipeline buried in permafrost

The thaw settlement of pipeline foundation soils in response to the operation of the first China-Russia Crude Oil Pipeline along the eastern flank of the northern Da Xing'anling Mountains in Northeast China was simulated in a physical model test (with a similitude ratio of 1/73) in a geotechnical centrifuge.Two pipes of a supported and an unsupported section were evaluated over a testing period for simulating 20 years of actual pipeline operation with seasonal cyclically changing oil and ambient temperatures.The results show that pipe settlement of the supported pipe was 45% of settlement of the unsupported pipe.Settlement for the unsupported section was approximately 35% of the thaw bulb depth below the initial pipe elevation,only 30% of that for the supported pipe due to the influence of the supports.The final thaw bulbs extended approximately 3.6 and 1.6 times of the pipe diameter below the unsupported and supported pipe bottom elevations,respectively.The sandbag supports kept frozen during the test period because of cooling effect of the thermosyphons.The maximum bending stress induced over the 20 m span length from bearing of the full cover over the pipe would be equivalent to 40% specified minimum yield strength (SMYS).Potential buckling of the pipe should be considered as the ground thaws.This study also offers important data for calibration and validation of numerical simulation models.
Temporal changes in seasonal precipitation over the Sahara Desert from 1979 to 2016

Rainfall variability dominates livelihoods in all countries of Saharan Africa.To better understand the processes involved in Sahara precipitation changes,we used the Global Precipitation Climatology Center (GPCC) dataset to examine dry and wet seasonal trends in the Sahara region from 1979 to 2016.We also used the European Centre for Medium-Range Weather Forecasts (ECMWF) to evaluate the general atmospheric circulation associated with seasonal change of Sahara precipitation.The Mann-Kendall test and Theil sens' slope estimator methods were adopted to test and estimate the significance and weight of precipitation trend,respectively.The results revealed that Sahara precipitation has increased significantly.The seasonal evaluation shows a positive trend of 0.42 mm/decade and 1.43 mm/decade in JAS (June,August,and September) seasons for the northern and southern Saharan Desert,respectively.Moreover,the JFMA (January,February,March,and April) period shows a negative trend but not statistically significant.An examination of the general circulation and moisture transport changes suggested an increase of rainfall in southern Sahara.The wet period is also driven by northward penetration of moisture originating from the Sahel region,African Easterly Jet (AEJ),and weakening in the upper tropospheric zonal wind.Summer rainfall has also been likely associated with positive anomalies of sea surface temperature (SST) in the North Tropical Atlantic (NTA) and the Mediterranean Sea.
LAI scale effect research based on compact airborne spectrographic imager data in the Heihe Oasis

As one of the key parameters for characterizing crop canopy structure, Leaf Area Index (LAI) has great significance in monitoring the crop growth and estimating the yield. However, due to the nonlinearity and spatial heterogeneity of LAI inversion model, there exists scale error in LAI inversion result, which limits the application of LAI product from different remote sensing data. Therefore, it is necessary to conduct studies on scale effect. This study was based on the Heihe Oasis, Zhangye city, Gansu province, China and the following works were carried out: Airborne hyperspectral CASI (Compact Airborne Spectrographic Imager) image and LAI statistic models were adopted in muti-scale LAI inversion. The overall difference of muti-scale LAI inversion was analyzed in an all-round way. This was based on two aspects, “first inversion and then integration” and “first integration and then inversion”, and on scale difference characteristics of three scale transformation methods. The generation mechanism of scale effect was refined, and the optimal LAI inversion model was expanded by Taylor expansion. By doing so, it quantitatively analyzed the contribution of various inversion processes to scale effect. It was found that the cubic polynomial regression model based on NDVI (940.7 nm, 712 nm) was the optimal model, where its coefficient of determination R2 and the correlation coefficient of test samples R reached 0.72 and 0.936, respectively. Combined with Taylor expansion, it analyzed the scale error generated by LAI inversion model. After the scale effect correction of one-dimensional and twodimensional variables, the correlation coefficient of CCD-LAI (China Environment Satellite HJ/CCD images) and CASI-LAI products (Compact Airborne Spectro graphic Imager products) increased from 0.793 to 0.875 and 0.901, respectively. The mean value, standard deviation, and relative true value of the two went consistent. Compared with onedimensional variable correction method, the twodimensional method had a better correction result. This research used the effective information in hyperspectral data as sub-pixels and adopted Taylor expansion to correct the scale error in large-scale and low-resolution LAI product, achieving large-scale and high-precision LAI monitoring.
Expansion and expression diversity of FAR1/FRS-like genes provides insights into flowering time regulation in roses

Roses are important horticultural plants with enormous diversity in flowers and flowering behavior. However, molecular regulation of flowering time variation in roses remains poorly characterized. Here, we report an expansion of the FAR1/FRS-like genes that correlates well with the switch to prostrate-to-erect growth of shoots upon flowering in Rosa wichuraiana 'Basye's Thornless' (BT). With the availability of the high-quality chromosome-level genome assembly for BT that we developed recently, we identified 91 RwFAR1/FRS-like genes, a significant expansion in contrast to 52 in Rosa chinensis 'Old Blush' (OB), a founder genotype in modern rose domestication. Rose FAR1/FRS-like proteins feature distinct variation in protein domain structures. The dispersed expansion of RwFAR1/FRS-like genes occurred specifically in clade I and II and is significantly associated with transposon insertion in BT. Most of the RwFAR1/FRS-like genes showed relatively higher expression level than their corresponding orthologs in OB. FAR1/FRS-like genes regulate light-signaling processes, shade avoidance, and flowering time in Arabidopsis thaliana. Therefore, the expansion and duplication of RwFAR 1/FRS-like genes, followed by diversification in gene expression, might offer a novel leverage point for further understanding the molecular regulation of the variation in shoot-growth behavior and flowering time in roses.
Comparison of different sampling strategies for debris flow susceptibility mapping: A case study using the centroids of the scarp area, flowing area and accumulation area of debris flow watersheds

The quality of debris flow susceptibility mapping varies with sampling strategies. This paper aims at comparing three sampling strategies and determining the optimal one to sample the debris flow watersheds. The three sampling strategies studied were the centroid of the scarp area (COSA), the centroid of the flowing area (COFA), and the centroid of the accumulation area (COAA) of debris flow watersheds. An inventory consisting of 150 debris flow watersheds and 12 conditioning factors were prepared for research. Firstly, the information gain ratio (IGR) method was used to analyze the predictive ability of the conditioning factors. Subsequently, 12 conditioning factors were involved in the modeling of artificial neural network (ANN), random forest (RF) and support vector machine (SVM). Then, the receiver operating characteristic curves (ROC) and the area under curves (AUC) were used to evaluate the model performance. Finally, a scoring system was used to score the quality of the debris flow susceptibility maps. Samples obtained from the accumulation area have the strongest predictive ability and can make the models achieve the best performance. The AUC values corresponding to the best model performance on the validation dataset were 0.861, 0.804 and 0.856 for SVM, ANN and RF respectively. The sampling strategy of the centroid of the scarp area is optimal with the highest quality of debris flow susceptibility maps having scores of 373470, 393241 and 362485 for SVM, ANN and RF respectively.
Simulation of Supercritical Carbon Dioxide Fracturing in Shale Gas Reservoir

In order to fracture shale gas reservoir with carbon dioxide as the working fluid,laboratory experiments were firstly conducted to measure the influence of carbon dioxide immersion on shale rock's properties,and then the coupling mechanism between stress and seepage during hydraulic fracturing was simulated based on cohesive zone model.The fracturing ability of carbon dioxide and water was also compared under the same working conditions,and finally sensitivity analysis(including elastic modulus of shale,filtration coefficient,pump rate and viscosity of carbon dioxide) were conducted based on field application.The results show that,the elastic modulus of shale increased by 32.2%,the Poisson's ratio decreased by 40.3% and the compressive strength decreases by 22.9% after geothermal reaction with carbon dioxide under 30 MPa and 335.15 K for 2 hours.Compared with water fracturing,carbon dioxide fracturing induces longer fracture(increased by 25.3%) and narrower fracture(decreased to 40.8%).The fracture tends to get longer and narrower with increasing elastic modulus of shale.As filtration coefficient increases,the maximum width of fracture decreases significantly,whereas the length changes little.Both the length and maximum width of fracture increase with increasing pump rate,however the changing rate of length tends to decrease.The influence of viscosity of carbon dioxide on both fracture width and length is negligible,which validates the stable feasibility of carbon dioxide fracturing in different formation conditions.
The Effects of Groundwater Depth on the Soil Evaporation in Horqin Sandy Land, China

The interactions between groundwater depth and soil hydrological processes, play an important role in both arid and semi-arid ecosystems. The effect of groundwater depth on soil water variations were neglected or not explicitly treated. In this paper, we combine a simulation experiment and a water flow module of HYDRUS-1D model to study the variation in soil evaporation under different groundwater depth conditions and the relationship between groundwater depth and evaporation efficiency in Horqin Sandy Land, China. The results showed that with an increase in groundwater depth, the evaporation of soil and the recharge of groundwater decrease. In this study, the groundwater recharge did not account for more than 21% of the soil evaporation for the depths of groundwater examined. The soil water content at 60 cm was less affected by the evaporation efficiency when the mean groundwater depth was 61 cm during the experimental period. In addition, the evaporation efficiency (the ratio of actual evaporation to potential evaporation) decreases with the increase in groundwater depth during the experiment. Furthermore, the soil evaporation was not affected by groundwater when the groundwater depth was deeper than 239 cm.
Vegetation Index Reconstruction and Linkage with Drought for the Source Region of the Yangtze River Based on Tree-ring Data

Variations in vegetation are closely related to climate change, but understanding of their characteristics and causes remains limited. As a typical semi-humid and semi-arid cold plateau region, it is important to understand the knowledge of long term Normalized Difference Vegetation Index (NDVI) variations and find the potential causes in the source region of the Yangtze River. Based on four tree-ring width chronologies, the regional mean NDVI for July and August spanning the period 1665–2013 was reconstructed using a regression model, and it explained 43.9% of the total variance during the period 1981–2013. In decadal, the reconstructed NDVI showed eight growth stages (1754–1764, 1766–1783, 1794–1811, 1828–1838, 1843–1855, 1862–1873, 1897–1909, and 1932–1945) and four degradation stages (1679–1698, 1726–1753, 1910–1923, and 1988–2000). And based on wavelet analysis, significant cycles of 2–3 yr and 3–8 yr were identified. In additional, there was a significant positive correlation between the NDVI and the Palmer Drought Severity Index (PDSI) during the past 349 yr, and they were mainly in phase. However, according to the results of correlation analysis between different grades of drought/wet and NDVI, there was significant asymmetry in extreme drought years and extreme wet years. In extreme drought years, NDVI was positively correlated with PDSI, and in extreme wet years they were negatively correlated.