Miracle-dz/UniFAR-FTUs huggingface dataset:
Magnitude correlations in a self-similar aftershock rates model of seismicity

Abstract. Crucial to the development of earthquake forecasting schemes is the manifestation of spatiotemporal correlations between earthquakes as highlighted, for example, by the notion of aftershocks. Here, we present an analysis of the statistical relation between subsequent magnitudes of a recently proposed self-similar aftershock rates model of seismicity, whose main distinguishing feature is that of interdependence between trigger and triggered events in terms of a time-varying frequency–magnitude distribution. By means of a particular statistical measure, we study the level of magnitude correlations under specific types of time conditioning, explain their provenance within the model framework and show that the type of null model chosen in the analysis plays a pivotal role in the type and strength of observed correlations. Specifically, we show that while the variations in the magnitude distribution can give rise to large trivial correlations between subsequent magnitudes, the non-trivial magnitude correlations are rather minimal. Simulations mimicking southern California (SC) show that these non-trivial correlations cannot be observed at the 3σ level using real-world catalogs for the magnitude of completeness as a reference. We conclude that only the time variations in the frequency–magnitude distribution might lead to significant improvements in earthquake forecasting.
Effects of Rice Husk Biochar and Calcium Amendment on Remediation of Saline Soil from Rice-shrimp Cropping System in Vietnamese Mekong Delta

In a rice-shrimp cropping system in Vietnamese Mekong Delta, more effective techniques are required to remediate the saline soils for lowing salinity to secure rice growth and productivity. The objective of this study was to evaluate the reclamation potential of biochar and calcium in laboratory experiments using a saline soil sample from the rice-shrimp system. Our hypothesis was that the addition of biochar might improve the infiltration rate, so remove salts more effectively, in particular sodium, from the saline soil. The experiment was set up with two kinds of rice husk biochar at rates of 0 and 50 g kg-1 combining with three levels of CaO (0, 0.5 and 2 g kg-1 soil, equivalent to 0, 0.5 and 2 Mg ha-1, respectively). Results indicated that biochar enhanced significantly drainage speed by 4 times compared to the control without biochar application. After leaching, exchangeable sodium percentage (ESP) in the soils was significantly lower in biochar treatments than in the control. Some other chemical indicators (K:Na and Ca:Na ratios) were also higher in biochar treatments. Although both biochars effectively removed salts from the saline soil, biochar with a lower Na+ adsorption capacity, a lower surface area and a higher amount of salts performed better in removing Na+ from soil. Combined application of biochar and CaO at low dose was more effective in improving soil properties related to Na+ leaching and ESP.
IMPACT OF WATER-LEVEL FLUCTUATION IN REDHILLS RESERVOIR ON POPULATION DYNAMICS OF CHENNAI CITY

Water-level fluctuations are a natural phenomenon that occurs in almost all aquatic ecosystems. With the increased population growth the world has seen in recent years, the resources that were once plentiful are becoming scarcer. Human-induced stressors such as increasing consumptive use of water are often linked to regions with significant growth in population. These stressors have the effect of lowering lake levels and reducing downstream flows, a major area of concern because of adverse economic and environmental impacts associated with progressive lowering of water levels. Chennai's water resources have been increasingly stressed by climate change and population growth. The secondary data (2007 to 2013) were collected from the Chennai Metro Water and sewage board for this analysis. Assessment of long-term impacts of projected changes in climate, population, land use and land cover, and groundwater availability on local water resources is critical to sustainable development. Water level depletion led to a drought. In this paper, an attempt has been made to investigate the groundwater level fluctuation with respect to nearby reservoir water level depletion and rainfall variability and also studying the water scarcity in
A framework for classification of volunteered geographic data based on user’s need

Abstract VGI is an attractive source of data, but the quality assurance limits its usages. This study proposes a framework to estimate the quality of the VGI and to classify them based on the user’s need. For this purpose, a set of properties is defined to describe the data in various aspects. The principal component analysis (PCA) method is applied to reach a new set of uncorrelated indicators (UI). Volunteered data is classified based on the user’s need and takes a quality index (QI). UI and QI values are used to train the ANN. Finally, the trained ANN determines the output of the network in a way that returns QI using the UI as inputs. The proposed method was applied to estimate the quality classes of VGI in a part of an urban area. According to the results of the confusion matrix, the total accuracy of the proposed framework was 81.6%.
A review on short term prediction of air pollutant concentrations

In the attempt to increase the production of the industrial sector to accommodate human needs; motor vehicles and power plants have led to the decline of air quality. The tremendous decline of air pollution levels can adversely affect human health, especially children, those elderly, as well as patients suffering from asthma and respiratory problems. As such, the air pollution modelling appears to be an im-portant tool to help the local authorities in giving early warning, apart from functioning as a guide to develop policies in near future. Hence, in order to predict the concentration of air pollutants that involves multiple parameters, both artificial neural network (ANN) and principal component regression (PCR) have been widely used, in comparison to classical multivariate time series. Besides, this paper also presents comprehensive literature on univariate time series modelling. Overall, the classical multivariate time series modelling has to be further investigated so as to overcome the limitations of ANN and PCR, including univariate time series methods in short-term predic-tion of air pollutant concentrations.
Rapidly Evolving Cirrus Clouds Modulated by Convectively Generated Gravity Waves

Cirrus clouds can strongly affect Earth's radiation balance, but questions remain about their growth mechanisms and rates. Here we show that gravity (buoyancy) waves generated by a storm in Northern Australia on 13 November 2015 caused an observable rippling effect on cirrus clouds up to 1,000 km away, as seen by the recently launched Himawari‐8/9 geostationary satellite. Regional model simulations reproduce the propagation speed of the wave, which agrees with theoretical predictions, and show that the wave amplitude and timing near the tropopause can account for the cirrus modulation. The observed cirrus reach peak optical depths of order 0.3–1.0 and appear roughly in phase with the arrival of the relative humidity maximum, providing new evidence that cirrus clouds can respond rapidly (<30 min) to environmental lifting. Moreover, the edge of a thick anvil cloud attached to the storm itself is observed to expand at the same speed as the wave, showing that the lifting mechanism can also apply to optically thicker ice clouds close to convective centers.
Canonical Decomposition of Wing Kinematics for a Straight Flying Insectivorous Bat

Bats are some of the most agile flyers in nature. Their wings are highly articulated which affords them very fine control over shape and form. This thesis investigates the flight of Hipposideros Pratti. The flight pattern studied is nominally level and straight. Measured wing kinematics are used to describe the wing motion. It is shown that Proper Orthogonal Decomposition (POD) can be used to effectively to filter the measured kinematics to eliminate outliers which usually manifest as low energy higher POD modes, but which can impact the stability of aerodynamic simulations. Through aerodynamic simulations it is established that the first two modes from the POD analysis recover 62% of the lift, and generates a drag force instead of thrust, whereas the first three modes recover 77% of the thrust and even more lift than the native kinematics. This demonstrates that mode 2, which features a combination of spanwise twisting (pitching) and chordwise cambering, is critical for the generation of lift, and more so for thrust. Based on these inferences, it is concluded that the first 7 modes are sufficient to represent the full native kinematics. The aerodynamic simulations are conducted using the immersed boundary method on 128 processors. They utilize a grid of 31 million cells and the bat wing is represented by about 50000 surface elements. The movement of the immersed wing surface is defined by piecewise cubic splines that describe the time evolution of each control point on the wing. The major contribution of this work is the decomposition of the native kinematics into canonical flapping wing physical descriptors comprising of the flapping motion, stroke-plane deviation, pitching motion, chordwise, and spanwise cambering. It is shown that the pitching mode harvests a Leading Edge Vortex (LEV) during the upstroke to produce thrust. It also stabilizes the LEV during downstroke, as a result, larger lift and thrust production is observed. Chordwise cambering mode allows the LEV to glide over and cover a large portion of the wing thus contributing to more lift, while the spanwise cambering mode mitigates the intensification of LEV during the upstroke by relative rotation of the outer part of the wing ( hand wing ) with respect to the inner part of the wing ( arm wing). While this thesis concerns itself with near straight-level flight, the proposed decomposition can be applied to any complex flight maneuver and provide a basis for unified comparison not only over different bat flight regimes but also across other flying insects and birds. Canonical Decomposition of Wing Kinematics For A Straight Flying Insectivorous Bat (Hipposideros Pratti)
Chemical Composition and Microbiological Quality of Laban Rayeb in Assuit City.

A total of 36 samples of Laban Rayeb were collected from 12 different small dairy plants in Assuit Governorate. samples were analyzed for their chemical composition and microbiological quality. The Results showed that the average values of acidity %, moisture, total solids, fat, total nitrogen, soluble nitrogen, soluble nitrogen coefficient were 1.1, 88.29, 11.66, 2.41, 0.52, 0.17 and 4.87, respectively. Moreover, microbiological analysis revealed that the log of total bacteria count ranged from 7.03 to7.21cfu, counts of lactic acid bacteria counts ranged from 5.781 to 6.353cfu, and the coccus group ranged from 5.83 to 6.29cfu and proteolytic bacteria ranged from 4.36 and 6.89cfu. Finally, yeasts and moulds count ranged from 0.00 to 5.21cfu in fresh Rayeb milk samples. Coliform bacteria couldn't be detected in all of the examined samples.
Response of Maize Crop to Water Deficit and Organic Fertilizers

Maximizing irrigation water productivity in irrigated crops, and expansion on organic agriculture are very important to overcome water shortage, and to improve environment preservation. Two field trails (summer seasons 2017 and 2018) were conducted at clay soil to examine the impact of, three amount of irrigation water (W); 100, 85, and 70% of ETC,, in conjunction with three fertilizer type; 100% of NPK (F1), 50% NPK + compost tea "CT" (F2), and 50% NPK + bio-fertilizer "BF" (F3), on ear parameters (length "CL", No. of row per ear "Cr", and grain mass per ear "Cm"), seed index "SI" (100 grain mass), harvest index "HI", grain yield "Gy", irrigation water productivity "IWP", and NPK uptake at shoots content. A split-plot design was used. Results illustrated that increasing water deficit (WD) percentage, resulted in progressively lower and significantly effect on all traits under study, and WD must not be less than 85%. , of ETC. On the other hand, a combination of organic (CT and/or BF) with NPK fertilizer recorded over values at all traits compared of sole NPK. In addition, there were significant effects between F3 or F2 to F1, however, the increase between F3 and F2, was insignificant.
Lowland stream restoration by sand addition: Impact, recovery, and beneficial effects on benthic invertebrates

Up to now, most lowland stream restoration projects were unsuccessful in terms of ecological recovery. Aiming to improve the success of stream restoration projects, a novel approach to restore sandy‐bottom lowland streams degraded by channel incision was launched, consisting of the addition of sand to the stream channel in combination with the introduction of coarse woody debris. Yet it remained unknown whether this novel measure of sand addition is actually effective in terms of biodiversity improvements. The aim of the present study was therefore to evaluate if sand addition can improve hydromorphological stream complexity on the short term leading to an increase in macroinvertebrate biodiversity. To this end, particle transport, water depth, current velocity, dissolved oxygen dynamics, and sediment composition were measured. The response of the macroinvertebrate community composition was determined at different stages during the disturbance and short‐term recovery process. Immediately downstream the sand addition site, transport and sedimentation of the sand were initially intense, until an equilibrium was reached and the physical conditions stabilized. The stream section matured fast as habitat formation took place within a short term. Macroinvertebrate diversity decreased initially but recovered rapidly following stabilization. Moreover, an increase in rheophilic taxa was observed in the newly formed habitats. Thus, although sand addition initially disturbed the stream, a relatively fast physical and biological recovery occurred, leading to improved instream conditions for a diverse macroinvertebrate community, including rheophilic taxa. Therefore, we concluded that sand addition is a promising restoration measure for incised lowland streams.
Household Fuel Choice in Urban Nepal: A Multinomial Logistic Regression Analysis

From the last decade of the 20th century, it has become increasing evident that uses of firewood, kerosene, LPG and electricity are the major sources of energy used by household for cooking, heating, lighting and cooling. The study examined the effect of socio-economic factors like income, education, geographical location, ethnicity across three different regions. Two cross-section data surveyed by National Living Standard Survey (NLSS) in 1995/96and in 2010/11 are used to analyze the end-use of energy in urban sector for cooking purpose. The studies found there have been significant changes in energy consumption behavior of urban household in these two time periods. Consumption of kerosene has declined over the period of time. Firewood has still contribution with significant amounts although people prefer LPG for cooking purpose. Result shows that household income plays significant role to switch from traditional and transitional fuel to modern fuel. Similarly, household education, ethnic group, geographical locations, family size has significant impact on fuel choice behavior of household. The result suggests that policies and interventions that raise household income, increase the level of education of household head could help to encourage the adaptation of modern energy source.
NUMERICAL SIMULATION OF THE FLOW AROUND A LIGHT AIRCRAFT WING

This work aims to study and simulate the behavior of flow over SAFAT-01’s wing using numerical simulation based on solving Reynolds’s Averaged Navier-Stokes equations coupled with K-ω turbulent model. The wing model is simple rectangular with elliptical ends. In the present work, aerodynamics characteristics and different flow phenomena were predicted at different design conditions (e.g. at different angles of attack) and at Re=5.2×10. The present study analysis the vortices which occur over wing and captured their effective regions at critical design conditions. This study indicates that the maximum lift coefficient for SAFAT-01’s wing is 1.44 occurred at stall angle of attack 12, maximum lift to drag ratio (L/D) is 26 which occurs at -4 , and the zero lift drag coefficient is 0.0142. To validate this numerical simulation, a typical wing which found in Ref. [3] was analyzed, a comparison between predicted results and available results indicate that this numerical simulation has high ability for predicting the aerodynamics characteristics.
Do Deltas Along the Crustal Dichotomy Boundary of Mars in the Gale Crater Region Record a Northern Ocean?

Deltaic deposits mapped along the Martian crustal dichotomy boundary scarp have been suggested to delineate an ancient ocean in the northern lowlands of Mars. Using recently acquired orbital data, we have expanded the dichotomy delta inventory and performed an updated analysis of delta front elevations, a proxy for paleo‐water levels. Our analysis focused near Gale crater, home of the Curiosity rover. We found that delta front elevations vary by approximately 2,400 m, but these elevation variations do not correspond to modeled deformation from true polar wander or Tharsis. Locally, delta front elevations vary by ≤60 m, and using present‐day topography, they correspond to distinct enclosed basins. We infer that these deltas formed in paleo‐lakes up to approximately 13,000 km2 and approximately 0.4 km deep, perhaps coeval with paleo‐lakes in Gale. Our results suggest that a northern ocean is not needed to explain the deltaic deposits in the Gale crater region.
Anatomy of a mega-rock slide at Forkastningsfjellet, Spitsbergen and its implications for landslide hazard and risk considerations

Rock slope failures are a potential source of danger in polar regions. A causal connection between slope failures and climate-related glacial and deglacial processes has been inferred for the growing number of documented events. In this context, we investigated a large-scale rotational rock slide affecting the coastal ridge of Spitsbergen’s Forkastningsfjellet. Based on a detailed structural description, we discuss the kinematics, timing and potential drivers of rock slide activity and present a preliminary landslide hazard assessment. The Forkastningsfjellet rock slide has a footprint of at least 2.03 km2. A minimum rock mass volume of 0.10 km3 was displaced either catastrophically or over a longer time period. Initial movement in the hanging wall of a NW-dipping listric sliding surface led to the fragmentation of the sliding mass into separated tilt blocks that created the present-day, stair-stepped morphology. The main rock slide release was probably related to the deglaciation of Isfjorden and the resulting instability of the weakened rock mass along the oversteepened slopes during Allerød times (~13,900–12,700 BP). Mass wasting and seacliff erosion, mainly controlled by the inherent discontinuities of the fractured and tilted rock masses, currently take place along the steep slopes of the coastal tilt blocks. A preliminary hazard analysis suggests a medium to high hazard for a reactivation of the slide or individual blocks, but uncertainty margins for this classification are large due to a lack of data. Poor control of total displacement data in particular contributes to the uncertainty. A high-acceleration reactivation of a large compartment of the slide (e.g., on the order of 10 million m3) could cause a displacement wave several metres high in Longyearbyen. These results indicate a need for further multidisciplinary investigations to better understand the extent and nature of the rock slide and parameters such as displacement velocities to support a more reliable hazard and risk assessment for the Longyearbyen region.
A vacancy‐rich, partially inverted spinelloid silicate, (Mg,Fe,Si)2(Si,□)O4, as a major matrix phase in shock melt veins of the Tenham and Suizhou L6 chondrites

A new high‐pressure silicate, (Mg,Fe,Si)2(Si,□)O4 with a tetragonal spinelloid structure, was discovered within shock melt veins in the Tenham and Suizhou meteorites, two highly shocked L6 ordinary chondrites. Relative to ringwoodite, this phase exhibits an inversion of Si coupled with intrinsic vacancies and a consequent reduction of symmetry. Most notably, the spinelloid makes up about 30–40 vol% of the matrix of shock veins with the remainder composed of a vitrified (Mg,Fe)SiO3 phase (in Tenham) or (Mg,Fe)SiO3‐rich clinopyroxene (in Suizhou); these phase assemblages constitute the bulk of the matrix in the shock veins. Previous assessments of the melt matrices concluded that majorite and akimotoite were the major phases. Our contrasting result requires revision of inferred conditions during shock melt cooling of the Tenham and Suizhou meteorites, revealing in particular a much higher quench rate (at least 5 × 103 K s−1) for veins of 100–500 μm diameter, thus overriding formation of the stable phase assemblage majoritic garnet plus periclase.
Subtropical Cyclone Anita's Potential to Tropical Transition Under Warmer Sea Surface Temperature Scenarios

On 6 March 2010, Anita, the first subtropical cyclone observed over the South Atlantic Ocean, formed near the southeastern coast of Brazil, and during its life cycle, Anita almost acquired a tropical structure. The potential of Anita to undergo tropical transition in scenarios of increased sea surface temperature (SST) was investigated through a set of numerical sensitivity experiments. The results show that, if the SST had been 2°C warmer throughout Anita's life cycle, the system would have undergone tropical transition in its maturity stage; however, if the SST had increased only during Anita's quasi‐stationary period, the tropical transition completion would have occurred only with higher values of SST (6°C).
Water quality modeling of the São Joaquim stream, Brazil

Water quality modeling is applied as a supporting tool for water quality management. It is useful in identifying environmental impacts from pollutants discharged into rivers and in predicting self-depuration capacity. This study aimed to simulate the water quality along a stretch in São Joaquim stream basin, in order to identify the main polluting sources in the stream and to propose measures to control pollution. The mathematical model, based on the mass balance in plug flow reactor, was implemented in an electronic spreadsheet. The modeling process involved the following stages: collecting the input data, calibration, sensitivity analysis, uncertainty analysis, and the generation of the scenarios. The calibration of the model has generated r2 above 0.68, and it was the indication that the model can explain most of the variance found in the measured data. The wastewater and the stream flow were considered the most sensitive parameters in the model. The uncertainty analysis has shown the probability of the dissolved-oxygen to be higher than or equal to 2 mg L-1, the minimum value allowed for the class 4, is 5.3 %. The main pollution sources in stream are the discharge of untreated domestic wastewater from São Joaquim City, and the surface runoff from the agricultural area. The study has shown that a wastewater treatment station must installed in the basin, in order to remove at least 93% of the organic matter currently discharged in the stream.