Loss Estimation Research Articles

A modified Soil and Water Assessment Tool Plus (M-SWAT+) model for sediment yield estimation

ABSTRACT The Soil and Water Assessment Tool Plus (SWAT+) model depends on the Modified Universal Soil Loss Equation (MUSLE), which in turn depends on the peak runoff rate for the estimation of soil loss from a catchment. The SWAT+ model generates a random number for each day in the process of peak runoff rate estimation from the catchment. On the other hand, the model provides calibration parameters like the peak rate adjustment factor for sediment routing in the tributary channels and main channels. There is uncertainty that how likely the SWAT+ model estimates the actual peak runoff rates. An improved MUSLE does not depend on the peak runoff rate, and, therefore, it minimizes uncertainty related to the peak runoff rate when estimating soil loss from the catchment in the SWAT+ environment. On the other hand, the effect of the topographic factor of the MUSLE or improved MUSLE on soil erosion and sediment transport is not explicitly explained. Therefore, we modify the source code of the SWAT+ model for sediment yield estimation by replacing the improved MUSLE and the best-fitted equations of the topographic factor in the source code. The modified SWAT+ model showed better performance than the original SWAT+ model.

Estimation of random incidence sound transmission loss of panels based on normal incidence sound transmission loss measurements

The performance of building sound insulation is an important parameter for evaluating the quality of construction projects. So far, the sound insulation performance testing of building walls requires the installation of large-dimensioned wall samples in specialized sound insulation laboratories, which is time-consuming and costly. If small-dimensioned components of the wall panels can be applied and quickly tested at the project site, it could significantly improve efficiency and reduce costs. To address this issue, this paper investigates a method for estimating the random incidence sound transmission loss of wall panels based on the measurement of the normal incidence sound transmission loss of corresponding small samples. Initially, the sound transmission loss of single-layer and composite structures is theoretically analyzed based on the theories of Equivalent Single Layer method and Layer-Wise method. Subsequently, the random incidence sound transmission loss is estimated by the normal incidence sound transmission loss. The methodology for estimating the random incidence sound transmission loss of wall panels proposed in this study offers both a practical approach and theoretical support for the rapid assessment of the sound insulation performance of building walls. This study is of great significance for improving the quality of construction projects and inspection efficiency.

Indoor environmental quality assessment in passively ventilated classrooms in Germany and estimation of ventilation energy losses

In this field study we present an approach for the comprehensive and room-specific assessment of parameters with the overall aim to realize energy-efficient provision of hygienically harmless and thermally comfortable indoor environmental quality in naturally ventilated non-residential buildings. The approach is based on (i) conformity assessment of room design parameters, (ii) empirical determination of theoretically expected occupant-specific supply air flow rates and corresponding air exchange rates, (iii) experimental determination of real occupant-specific supply air flow rates and corresponding air exchange rates, (iv) measurement of indoor environmental exposure conditions of T, RH, cCO2, cPM2.5 and cTVOC, and (v) determination of real energy demands for the prevailing ventilation scheme. Underlying assessment criteria comprise the indoor environmental parameters of category II of EN 16798-1: Temperature T = 20 °C–24 °C, and relative humidity RH = 25 %–60 % as well as the guide values of the German Federal Environment Agency for cCO2cPM2.5 and cTVOC of 1000 ppm, 15 μg m−3, and 1 mg m−3, respectively.Investigation objects are six naturally ventilated classrooms of a German secondary school. Major factors influencing indoor environmental quality in these classrooms are the specific room volume per occupant and the window opening area. It is concluded that the rigorous implementation of ventilation recommendations laid down by the German Federal Environment Agency is ineffective with respect to anticipated indoor environmental parameters and inefficient with respect to ventilation energy losses on the order of about 10 kWh m−2 a−1 to 30 kWh m−2 a−1.

Assessment of Seismic Potential Impacts of an Mw 8.4 Hypothetical Earthquake in Central Nepal Province

The national capital of Nepal is situated on a lacustrine sediment basin. The country has had major seismic events that have resulted in significant damage to structures, human casualties, and substantial economic losses. Mitigating seismic risk is a challenging problem in Nepal due to poor construction practices, no enforcement of seismic safety guidelines, and a lack of awareness in the public. Seismic risk mitigation is essential in improving seismic resistance of buildings, and in reducing the economic loss and casualties in the forthcoming seismic events. The scientific results of earthquake loss estimation studies will lead to improve the policies towards seismic resilience.The current research uses the SELENA (Seismic Loss Estimation using a Logic Tree Approach) tool to explore the seismic damage to buildings, human loss, and seismic risk in the 11 districts due to a scenario earthquake. The seismic risk of the study region due to the scenario earthquake is determined through fragility functions. The expected economic losses vary from 0.1 to 0.6 million dollars, and the possible casualties range from 1,000 to 5,000. The outcome of the study will be helpful for the local authorities and policymakers to take mitigation measures for the existing buildings.

Estimation of intraoperative blood loss in hepatopancreatobiliary surgery: a Delphi consensus process of the European-African Hepato-Pancreato-Biliary Association (E-AHPBA).

Estimation of intraoperative blood loss in hepatopancreatobiliary surgery: a Delphi consensus process of the European-African Hepato-Pancreato-Biliary Association (E-AHPBA).

Physics-Informed Neural Networks for Path Loss Estimation by Solving Electromagnetic Integral Equations

Physics-Informed Neural Networks for Path Loss Estimation by Solving Electromagnetic Integral Equations

Urban flooding damage prediction in matrix scenarios of extreme rainfall using a convolutional neural network

The pivotal role of quantitative risk assessment in managing urban stormwater is underscored by the high spatial heterogeneity and complex non-stationarity complex of urban flooding. Conventional methods, reliant on measurable data, often fall short in accurately mapping spatial variations and gauging the full impacts of urban flooding. Addressing this gap, this study proposed a robust convolutional neural networks (CNN)-based tool, specifically designed for urban flooding risk and economic losses estimation under extreme design rainfall scenarios. Furthermore, the study validates the transferability of CNN models trained in data-abundant regions to similar but data-scarce regions, using Guangzhou as a case study for urban flooding damage prediction. The findings reveal that the most affected areas, particularly the old, densely built-up urban areas in the south-central Guangzhou, are susceptible to significant economic losses during extreme rainfall events. Notably, under the most severe scenario (Scenario 5), estimated economic losses amount to approximately $6359.91 million, with industrial and residential sectors bearing the brunt, accounting for 28.29 % and 39.94 % of the total losses, respectively. These insights are crucial for prioritizing mitigation efforts and formulating effective evacuation strategies in high-risk areas, ultimately aiding in the reduction of economic losses.

Evaluating the risk perception due to land subsidence within onyeama mine, South East Nigeria

This paper conducts a systematic evaluation of risk perception due to land subsidence monitored within a major coalmine in Nigeria. There is a general assumption in most hazard research that risk perception should be a first determinant of whether adaptive action is taken or not. To gain a comprehensive insight using land subsidence, we propose a technique that integrates quantitative evaluation (vulnerability assessment) and subjective evaluation (perception analysis) of human responses towards this environmental hazard. Perception of risk, which is dependent on risk magnitude appraisal and risk acceptance, was amplified into the overall risk constellation. Vulnerability assessment was conducted based on the human development index (HDI) at fourteen locations investigated for the study, with particular focus on building networks as an index for loss estimation. We exploit data from Sentinel-1 Synthetic Aperture Radar (SAR) Satellites and Small-Baseline Subset Differential Interferometric Synthetic Aperture Radar (SBAS-DInSAR) technique to map Onyeama Coal Mine in South – East, Nigeria. From the HDI and according to the vulnerability assessment, the margin of error (E) is estimated as 0.06754, with samples proportion of ρˆ= 0.85. The 95 % confidence interval for proportion is in the range of 0.783 to 0.917. The results indicates that with an average of a finite population size of N = 1413 buildings at each study location, about 85 % of the samples (n=100) do not recognize that land subsidence is ongoing and constantly affecting their buildings. As a result of this ignorance and lack of awareness, constantly progressing subsidence becomes normalized in peoples’ perceptions, and their outlook toward danger is not integrated into day-to-day habits. Thus, risk perception is a lesser determinant of mitigation responses towards slowly progressing subsidence, and not actual exposure leading to action.

Seismicity of Morocco and simulation of 08.09.2023 earthuake consequnces with “Extremum” system application

This paper reports the use of regional intensity attenuation equations for the territory of Morocco by modeling the impact of the destructive earthquake of September 8, 2023 in the country. The relevance of the study follows from the needed reliable estimates of possible loss due to earthquakes in order to aid the decision-making process for the response and the proper choice of a search and rescue strategy for the heavily affected settlements. The paper has for its goal the calibration of the “Extremum” system seismic intensity attenuation models for the territory of Morocco. Our study is the first to analyze the seismic intensity attenuation equations obtained by researchers at different times with a view to their applicability to near real time loss assessment for strong events occurring in the area of study. We investigate as well how the results of earthquake loss simulation are affected by regional damage matrixes. Computer simulation was applied to the assessment of the possible impact due to the September 8, 2023 earthquake using the “Extremum” system developed with authors’ participation.This paper provides preliminary results of modeling the impact of the Morocco earthquake, as well as an assessment of the convergence achieved by calculated and observed intensities for various intensity prediction equations obtained before for the Morocco and adjacent areas within the Alpine-Himalayan seismically active belt.

Analysis and estimation of power losses in high-power, high-frequency transformers for isolated DC/DC converters

The paper presents an in-depth analysis of the power losses in the windings and the cores of two different transformers as applied to a phase-shifted full bridge (PSFB) converter at the power level of 20–25 kW and the switching frequency of 50 kHz. The main difference in the construction of the considered devices was the method of winding realization as well as the shape and material of the cores. The influence of the winding geometry on the conduction losses was analyzed, and the losses in the cores were analytically estimated, taking into account the operating conditions of these elements in the full-bridge system with phase-shift modulation. Original resistive models of windings made of cooper sheets are presented. The obtained results were verified by experimental tests carried out in an isolated full-bridge DC/DC converter.

The acetabularization index: a novel measure of acromial bone loss prior to reverse shoulder arthroplasty.

Acromial stress fractures following reverse shoulder arthroplasty (RSA) have gained attention among specialized surgeons over the past decades craving answers regarding predisposing factors and technical aspects as how to avoid the complication. This study introduces the acetabularization index (AI) for the preoperative estimation of acromial bone loss attributed to acetabularization in cases of cuff tear arthropathy (CTA). The acromiohumeral interval (AHI), extent of acromial acetabularization (AA), acromial height (AH), and width of acetabularization (r) were measured on preoperative radiographs and two-dimensional computed tomography scans (2D CT) of patients who underwent RSA within the timeline 2019-2023 for CTA. The AI calculated . The CTA grade was determined according to the Hamada classification. The AI values on radiographs and 2D CT were compared by a Student's t-test. Possible correlation between the AI and AHI was investigated via Pearson's coefficient. The intraclass correlation coefficient (ICC) was employed to test the interobserver reliability among two independent testers. The radiographs and 2D CT scans of thirty-three patients who underwent RSA were analyzed. The mean AHI, AH, AA, r, and AI values on radiographs were 5.5 ± 2mm, 10 ± 2mm, 2 ± 2mm, 30 ± 4mm, 16 ± 16%, respectively. On 2D CT, the corresponding mean values were 4.7 ± 2.5mm, 10.8 ± 2.65mm, 2.45 ± 2.35mm, and 30 ± 4.5, and 22.3 ± 22%, respectively. There was a statistically significant difference between the AI values on radiographs and 2D CT (P = .000). The Pearson's correlation coefficient demonstrated a negative correlation between AI and AHI (r = - 0.33). Excellent reliability was observed by the ICC values for all parameters in both groups among two testers. The AI is a reliably measurable tool on radiographs and 2D CT scans; however, the measurements derived from radiographs vary significantly from CT based measurements due to projection restrictions. Grade IVB of the Hamada/Fukuda classification is associated with the highest AI values. Further research is warranted to assess the clinical utility of this index as a predictive tool for postoperative acromial stress fractures.

Effect of Flood on Poverty Status: Evidence from Sugar cane Farmers in Kwara State and Osun State of Nigeria

In Nigeria, sugarcane is a prominent crop and the primary crop used to produce sugar. However, floods have been a major tragedy that has troubled Nigeria's small-scale farmers. The bulk of rural poor people are these small-scale farmers, and as poverty rates have been rising over time, corrective action is required. This study was therefore carried out to assess the poverty status of sugar cane farming households (affected by flood, and unaffected by flood) in Kwara/Osun State of Nigeria. The study employed two-stage sampling technique to select 120 sugarcane farming households in the study area. Descriptive statistics, the Flood Loss Estimation, Logit Regression and Foster Greer Thorbecke (FGT) are the empirical analytical tools employed to analyze the data collected for the study. The results of the poverty index analysis revealed that 46 percent of the respondents are relatively poor, the poverty depth was 0.16 which implies that 16 percent were below the poverty line and the poverty severity was 0.07 which implies that 7 percent of the respondents were severely poor. Also, it revealed that flood shocks, gender, household size, household income, access to credit and membership to social organization were significant determinants of poverty. The study then came to the conclusion that many coping mechanisms people employ are corrosive because they have detrimental long-term implications on the sustainability of household subsistence. For future risk assessments and flood mitigation, the study advises using a holistic strategy and adept models. The remedies outlined in this paper would help the government, private sector, and sugar cane farmers economically.

A framework for post-windstorm functional recovery of non-residential buildings applied to hospitals

This study introduces a framework for recovery-based design in wind engineering. Currently, research is well advanced to implement this approach in earthquake engineering, with the scope of improving the resilience of structures and critical infrastructure, to achieve a durable and re-occupiable built environment after the occurrence of a disaster, and estimating downtimes and quantifying service disruption. The concept of interdependencies between the nonstructural components (building envelope) and a building’s functions is realized using Fault-Tree Analysis (FTA). Using this method allows the construction of fragility curves of systems of components and services using information as weights to reduce epistemic uncertainties, and a hypothetical recovery curve for the functionality of building services based on exposure to the hazard’s impact on the building envelope. The recovery process established here highlights the fundamental importance of accurate estimation of service losses. The methodology is applied to 4 hospitals located in different climatic regions in the United States surveyed using the database of EYP Architecture & Engineering. The analysis showed the importance of building design factors; such as the location of services relative to the envelope, number of stories, and the Window-to-Wall Ratio as significant influences on the risk of service disruption and recovery.

Emergent constraints on future Amazon climate change-induced carbon loss using past global warming trends

Reducing uncertainty in the response of the Amazon rainforest, a vital component of the Earth system, to future climate change is crucial for refining climate projections. Here we demonstrate an emergent constraint (EC) on the future response of the Amazon carbon cycle to climate change across CMIP6 Earth system models. Models that overestimate past global warming trends, tend to estimate hotter and drier future Amazon conditions, driven by northward shifts of the intertropical convergence zone over the Atlantic Ocean, causing greater Amazon carbon loss. The proposed EC changes the mean CMIP6 Amazon climate-induced carbon loss estimate (excluding CO2 fertilisation and land-use change impacts) from −0.27 (−0.59–0.05) to −0.16 (−0.42–0.10) GtC year−1 at 4.4 °C warming level, reducing the variance by 34%. This study implies that climate-induced carbon loss in the Amazon rainforest by 2100 is less than thought and that past global temperature trends can be used to refine regional carbon cycle projections.

Estimation of soil loss using RUSLE model and GIS tools: Case study in the Jucusbamba Micro-Watershed (Amazonas, NW Peru)

Human activities have intensified soil erosion globally, negatively impacting the physical, chemical, and microbiological quality of water and soil. This study estimated soil loss in the Jucusbamba Micro-Watershed (Amazonas, northwestern Peru) using the Revised Universal Soil Loss Equation (RUSLE) integrated with Geographic Information Systems (GIS) and remote sensing (RS) data. Meteorological data, soil maps, digital elevation models, and land cover and use maps were integrated into a GIS environment to predict the spatial distribution of erosion. The results showed five classes of soil loss severity: slight (93.34%), moderate (3.94%), high (1.82%), very high (0.61%), and severe (0.29%). Areas with high, very high, and severe erosion levels were mainly located in the middle and lower parts of the micro-watershed. The average annual soil loss was estimated at 23.24 t/ha/year. The information obtained is crucial for the formulation of soil management plans and programs to address erosion problems in the Jucusbamba River Micro-Watershed. Future research should focus on validating these models through field studies and implementing soil conservation practices based on these findings. Keywords: Amazonas, hydrology, RUSLE model, water erosion map, watershed.

Loss of cognitive function in Mexican children due to lead exposure and the associated economic costs

BackgroundLead exposure reduces the cognitive development and future economic prospects of children. While previous studies in high-income settings have explored productivity losses associated with lead exposure, limited research has focused on low and middle-income countries like Mexico. ObjectivesThis study aims to provide a comprehensive assessment of the economic implications of lead exposure on Mexican children using, for the first time, nationally representative Blood Lead Levels (BLLs) measurements in children aged 1–4, specifically focusing on the costs of forgone lifetime income due to cognitive losses. MethodsBLLs of children aged 1–4 were extracted from the 2018–2019 National Health and Nutrition Survey (ENSANUT). Estimations of cognitive losses were derived from a log-linear relationship between BLLs and IQ loss. Lost lifetime economic productivity per child was calculated, assuming a 2% reduction in lifetime potential productivity for each IQ point lost due to lead exposure, based on previous literature (Attina and Trasande, 2013; Larsen and Sánchez-Triana, 2023). Productivity data were obtained from representative sources for Mexico. ResultsThe estimated economic loss amounted to US $33.02 billion, equivalent to 2.76% of Mexico's Gross Domestic Product (GDP) in 2019 (calculated for a 1-year cohort). On a national scale, the long-term loss of cognition for children 1–4 years old is 4.14 IQ points per child due to lead exposure, with significant variability across States (range: 3.26 to 5.26). Lead-poisoned children (≥5 μg/dL) suffered an average loss of 6.42 IQ points (range: 0 to 6.97). In terms of economic impact, some States like Chiapas experienced losses of 7.08% of its GDP, while others had losses as low as 0.67%. Intriguingly, states with lower Human Development Index (HDIs) exhibited relatively higher economic losses despite lower average blood lead levels. DiscussionThe heterogeneous impact of lead exposure across Mexican states underscores the necessity for tailored regional policies. These findings emphasize the urgency for targeted interventions and informed policy measures to mitigate the socioeconomic consequences of lead exposure on Mexican children.

Suggested Interdisciplinary Approach for Managing Postpartum Haemorrhage Caused by Uterine Atony-A Call for Updated Guidelines

Postpartum Hemorrhage (PPH) is a significant cause of maternal morbidity and mortality, often exacerbated by inadequate adherence to established guidelines. This article examines the critical role of uterine atony and explores the impact of factors such as inaccurate blood loss estimation and hematological complications. It critiques the existing clinical guidelines for insufficiently addressing the role of hematologists and proposes the integration of early assessment techniques, including viscoelastic hemostatic assays and targeted fibrinogen replacement, to more effectively manage coagulopathy. The article also highlights recent advancements, such as the Alma device, and advocates for a multidisciplinary approach that includes both obstetricians and hematologists to enhance PPH management and improve patient outcomes.

Estimation of splice losses between a photonic crystal fiber and a conventional single mode fiber and between two different photonic crystal fibers without and with transverse offset and angular misalignment

Estimation of splice losses between a photonic crystal fiber and a conventional single mode fiber and between two different photonic crystal fibers without and with transverse offset and angular misalignment

Tank pool fire domino effect prevention by inherently safer layout planning: A techno-economic analytical index

Tank pool fire domino effects, represented by their capacities of accident consequence escalation and extensive damages, present substantial safety challenges within chemical storage systems. In this work, the inherent safety concept is introduced to proactively address these challenges while ensuring cost-effectiveness. Accordingly, a dedicated novel metric called Inherent Safety & Economic Risk Index (IS&ERI) is proposed to make safety and cost trade-offs for indicating the risk levels of various tank farm layout options. To develop the IS&ERI, the Dow's loss estimate procedure is adapted for representing the economic implications, and the Bayesian Networks are employed for indicating the failure probabilities of target units considering the synergistic effects of multiple pool fires. Two improved graph theory metrics are presented to determine the root nodes of the Bayesian Networks. For demonstrating the proposed IS&ERI, a case study is conducted and the results show that the IS&ERI of 4 tank farm layout options are 0.2991, 0.3120, 0.3525, and 0.2285, implying that Option 4 is the best layout with the lowest potential loss in case of the pool fire domino effects. As the key research contribution, the IS&ERI is presented and it can be used as a useful tool to compare and select the best tank farm layout option to eliminate or significantly reduce the knock-on effects of tank pool fires at their sources.

Relationship between growth and ambulation loss in Duchenne muscular dystrophy boys on steroids.

Treatment with glucocorticoids (GCs) is part of the standard of care in Duchenne muscular dystrophy, but excess weight gain and height stunting are common side-effects. It is still unclear how these growth-related side-effects affect motor function. This retrospective cohort study utilized 2228 observations from 648 participants in the UK NorthStar database who had growth and ambulation data recorded between 2006 and 2020. Joint modelling was used to analyse the effect of longitudinal growth centiles on loss of ambulation with respect to GC type and regimen. Loss of ambulation was observed in 113 patients. National estimates of loss of ambulation age were updated by GC group and showed no significant association between loss of ambulation risk and absolute growth centile. However, yearly drift in weight and/or height centile had an associated risk effect on loss of ambulation. Over a 2-year period, a yearly drift in weight from the 50th to the 75th, 75th to the 90th and 90th to the 95th centile was associated with 138%, 118% and 64% increased risk of loss of ambulation, respectively. Conversely, a 2-year drift in height from the 50th to the 25th, 25th to the 10th and 10th to the 5th centile was associated with 53%, 49% and 35% decreased risk of loss of ambulation, respectively. Our results suggest a complex relationship between growth and loss of ambulation in Duchenne muscular dystrophy boys on chronic GCs, the first step in understanding the effects of drugs which also affect growth patterns.