bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment and Enhancement of Ecosystem Service Supply Efficiency Based on Production Possibility Frontier: A Case Study of the Loess Plateau in Northern Shaanxi
Authors: Yan Zhenjun , Wang Yirong , Hu Xu , Luo Wen
Published: September 2023

Enhancing the supply efficiency of ecosystem services plays a central role in improving both natural ecosystems and human well-being. Taking the Loess Plateau of Northern Shaanxi as an example, this study utilizes InVEST to assess the ecosystem services of water yield and habitat quality. The optimal solutions for the combination of these two services are calculated on the basis of the Pareto principle. The production possibility frontier curves for the two services are fitted, and the services’ supply efficiency is measured. Furthermore, this study employs ordinary least squares and geographically weighted regression to analyze the dominant factors affecting supply efficiency. The results comprise the following findings: (1) There are eighteen solutions representing the optimal combinations between the two services. (2) The supply efficiency of the two services increases from northwest to southeast in spatial distribution. (3) The dominant factors vary among different zones of supply efficiency. Population, hydrology, and gross domestic product (GDP) are the dominant factors in the general-efficiency, sub-low-efficiency, and low-efficiency supply zones, respectively. Hydrology, NDVI, and GDP are the dominant factors in the sub-high-efficiency supply zone, while GDP, terrain, and population are the dominant factors in the high-efficiency supply zone. In conclusion, this paper proposes recommendations for reducing trade-offs and enhancing supply efficiency between ecosystem services. These include dynamic supervising for the high-efficiency supply zone, moderate greening in the sub-high-efficiency supply zone, stabilizing the population in the general-efficiency supply zone, and reducing development intensity in low- and sub-low-efficiency zones. The study reveals the potential and approaches for improving the supply of ecosystem services and offers guidance for formulating ecological protection plans.
Modified Accuracy of RANS Modeling of Urban Pollutant Flow within Generic Building Clusters Using a High-Quality Full-Scale Dispersion Dataset
Authors: Kavian Nezhad Mohammad Reza , RahnamayBahambary Khashayar , Lange Carlos F. , Fleck Brian A.
Published: September 2023

To improve the reliability of the computational fluid dynamics (CFD) models of wind-driven pollutant dispersion within urban settings, a re-calibration study is conducted to optimize the standard k−ε model. A modified optimization framework based on the genetic algorithm is adapted to alleviate the computational expenses and to further identify ranges for each empirical coefficient to achieve the most reliable and accurate predictions. A robust objective function is defined, incorporating both the flow parameters and pollutant concentration through several linear and logarithmic measures. The coefficients are trained using high-quality and full-scale tracer experiments in a mock urban arrangement simulating a building array. The proposed ranges are 0.14≤Cμ≤0.15, 1.30≤Cε1≤1.46, 1.68≤Cε2≤1.80, 1.12≤σε≤1.20, and 0.87≤σk≤1.00. A thorough evaluation of the predicted flow and concentration fields indicates the modified closure is effective. The fraction of predictions within the acceptable ranges from measurements has increased by 8% for pollutant concentration and 27% for turbulence kinetic energy. The generality of the calibrated model is further tested by modeling additional cases with different meteorological conditions, in which the calculated validation metrics attest to the noteworthy improvements in predictions.
Study of Technological Advancement and Challenges of Façade System for Sustainable Building: Current Design Practice
Authors: Fernando Dushan , Navaratnam Satheeskumar , Rajeev Pathmanathan , Sanjayan Jay
Published: September 2023

Currently, several façade systems exist to enable sustainable building design. The biggest challenges for façade designers are to identify new technology and effective, sustainable systems that enable high structural and sustainable performance while producing a good aesthetic. Therefore, this paper aims to review the performance of existing façade systems for sustainable building designs and their limitations. Among modern façade systems, Double Skin Façades (DSF) show promise for energy efficiency, indoor air quality, and aesthetics. However, they face challenges like sound transmission between floors, higher initial costs, and outer skin vibrations. Furthermore, adaptive façades gained popularity for their active methods of achieving energy performance and comfort benefits but encountered complexities in design and construction, demanding codes and standards. Green wall systems enhance air quality and aesthetics, while photovoltaic façade systems reduce electricity costs, but both systems face higher initial costs and maintenance challenges. The review indicates that to produce a sustainable building design, architects, engineers, and builders must consider a sustainable façade system that enables high energy efficiency, less cost, better occupant comfort, and fewer environmental impacts.
Assessing the Potential of Hybrid-Based Metaheuristic Algorithms Integrated with ANNs for Accurate Reference Evapotranspiration Forecasting
Authors: Khairan Hadeel E. , Zubaidi Salah L. , Al-Mukhtar Mustafa , Dulaimi Anmar , Al-Bugharbee Hussein , Al-Faraj Furat A. , Ridha Hussein Mohammed
Published: September 2023

Evapotranspiration (ETo) is one of the most important processes in the hydrologic cycle, with specific application to sustainable water resource management. As such, this study aims to evaluate the predictive ability of a novel method for monthly ETo estimation, using a hybrid model comprising data pre-processing and an artificial neural network (ANN), integrated with the hybrid particle swarm optimisation–grey wolf optimiser algorithm (PSOGWO). Monthly data from Al-Kut City, Iraq, over the period 1990 to 2020, were used for model training, testing, and validation. The predictive accuracy of the proposed model was compared with other cutting-edge algorithms, including the slime mould algorithm (SMA), the marine predators algorithm (MPA), and the constriction coefficient-based particle swarm optimisation and chaotic gravitational search algorithm (CPSOCGSA). A number of graphical methods and statistical criteria were used to evaluate the models, including root mean squared error (RMSE), Nash–Sutcliffe model efficiency (NSE), coefficient of determination (R2), maximum absolute error (MAE), and normalised mean standard error (NMSE). The results revealed that all the models are efficient, with high simulation levels. The PSOGWO–ANN model is slightly better than the other approaches, with an R2 = 0.977, MAE = 0.1445, and RMSE = 0.078. Due to its high predictive accuracy and low error, the proposed hybrid model can be considered a promising technique.
Simulating Environmental Issues: New Digital Tools to Teach Biology In Silico
Authors: Becker Liane , Dreesmann Daniel C.
Published: September 2023

Computers have been an indispensable part of human working and private life for decades, and in classrooms the use of digital devices and tools is increasing as a result of digitalization. In this study, we aimed to test the potential of computer simulations as digital tools in biology lessons to convey environmental issues. For this purpose, we conducted an online survey and evaluated 137 responses from German high-school students between 14 and 20 years of age. We asked the students about their attitude towards computer simulations as digital tools in biology lessons and tested the students’ knowledge about models and computer simulations as well as their basic knowledge about plant morphology. Additionally, we investigated the students’ self-perceived computer skills and their motivation to work with computers within information and communication technologies (ICTs). Our results show a relationship between high self-perceived computer skills and high motivation to work with computers and a high responsiveness to learning about environmental issues in silico (computer-based), even if gender differences are visible. Therefore, including computer simulations as a student-centered method can be profitable for students, increasing their understanding of environmental issues and combating their lack of botanical knowledge.
What Factors Impact Visitors’ Intentions to Use Location-Based AR Games? An Empirical Study from Chinese Cultural Heritage Sites
Authors: Guo Jiahui , Pan Younghwan
Published: September 2023

Location-based AR games have been discussed as a promising means of providing visitors with meaningful experiences at cultural heritage sites, with great potential to enhance users’ positive emotions and well-being. This research created a conceptual model to empirically evaluate the impact of location-based AR games on the experiential intentions of cultural heritage sites based on the broaden-and-build theory of positive emotions. The model was empirically validated using confirmatory factor analysis (CFA) and tested using structural equation modeling (SEM) on 260 visitors who had played location-based AR games at several Chinese cultural heritage sites. The results suggested that visitors’ positive emotions (fulfillment, enjoyment, and self-existence) in location-based AR games positively impact the intention to use location-based AR games. Further, this study demonstrated that competence, relatedness, immersion, presence, interaction existence, emotional existence, and social existence significantly impact tourists’ positive emotional experience. The findings of this study help to complement the application of positive-affect expansion and building theory to the field of cultural heritage research while providing practical insights into the experience of cultural heritage sites.
Including Sustainability Criteria in the Front End of Innovation in Technology Ventures
Authors: de Antonio Boada Paola Andrea , Durán Julian Fernando Ordoñez , Gómez Ávila Fabio Leonardo , Ferreira João Carlos Espindola
Published: September 2023

This study evaluates the presence of sustainability parameters in the product development process, especially in the early stages of innovation, using the Sustainability Technology Readiness Level (STRL) tool. STRL assesses the initial planning of products or product and service systems (PSS) and suggests possibilities for incorporating sustainable features in the short, medium, and long term based on responses from startups (EBTs). The research was conducted in two ecosystems at different maturity levels: Florianópolis (Brazil), a more mature stage, and Santander (Colombia), which is growing, considering their cultural and social differences. To validate the STRL tool, four out of the eighteen winning startups from the MuEBTe SANTANDER public funding project in Colombia were selected. Characteristics of the two researched ecosystems, their actors, strengths, approaches, and expansion possibilities were identified and compared. The innovation lies in establishing a sustainable baseline when applying the tool by acquiring the front-end characteristic matrix. It was observed that sustainability as a variable has relevance and independence from product design in product planning, allowing for the selection of short, medium, and long-term actions throughout the product’s lifecycle. It was concluded that considering sustainability involves context and vision, resulting in significant choices of materials, processes, and production methods that add value and appreciation for the customer.
Multi-Period Optimal Power Flow with Photovoltaic Generation Considering Optimized Power Factor Control
Authors: de Souza Cícero Augusto , da Silva Diego Jose , Rossoni Priscila , Belati Edmarcio Antonio , Pelizari Ademir , López-Lezama Jesús M. , Muñoz-Galeano Nicolás
Published: September 2023

This paper presents a Multi-Period Optimal Power Flow (MOPF) modeling applied to the minimization of energy losses in Distribution Networks (DNs) considering the reactive power control of Photovoltaic Generation (PVG) that can be applied to both short-term and long-term operation planning. Depending on the PV Power Factor (PVpf) limitations, PVG may provide both active and reactive power. The optimal power factor control on the buses with PVG contributes to an economical and safe operation, minimizing losses and improving the voltage profile of the DN. The proposed MOPF was modeled in order to minimize active energy losses subject to grid constraints and PVpf limitations. The variations of loads and PVG were discretized hour by hour, composing a time horizon of 24 h for day-ahead planning; nonetheless, the methodology can be applied to any other time period, such as a month, year, etc., by simply having generation and load forecasts. To demonstrate the effectiveness and applicability of the proposed approach, various tests were carried out on 33-bus and 69-bus distribution test systems. The analyses considered the DN operating with PVG in four different cases: (a) PVpf fixed at 1.0; (b) PVpf fixed at 0.9 capacitive; (c) hourly PVpf optimization; and (d) optimization of PVpf for a single value. The results show that a single optimal adjustment of PVpf minimizes losses, improves voltage profile, and promotes safe operation, avoiding multiple PVpf adjustments during the operating time horizon. The algorithm is extremely fast, taking around 2 s to reach a solution.
The Coupling and Coordination of Urban Modernization and Low-Carbon Development
Authors: Hu Wei , Liu Jingsong
Published: September 2023

In the context of global resource scarcity, the integrated and coordinated development of urban modernization and low-carbon development is becoming more and more crucial. In order to calculate the degree of coupling coordination between urban modernization and low-carbon growth in 31 Chinese provinces from 2010 to 2021, this paper thoroughly applies the entropy approach and coupling coordination model; the geographical correlation of the degree of coupling coordination of various regions was confirmed using the Moran’s I test method; and by utilizing the gray correlation degree model, we examined the elements that affect the degree of coupling coordination between the two in the various provinces. We found that: (1) there are periodic fluctuations in the coupling coordination between the two during the research period, with a general rising tendency year after year; (2) the degree of coupling and coordination between the two shows the characteristics of HH clustering (eastern region) and LL clustering (western region); and (3) the degree of coupling and coordination between the two is influenced by different factors in different regions. Overall, low-carbon variables have a significant impact on the eastern area, but urban modernization factors have a significant impact on the central, western, and northeastern regions. This study can provide policy recommendations for provincial governments in various regions, help identify favorable factors for coordinated development, and improve the role of some influencing factors in a targeted manner, thereby improving the level of urban modernization and low-carbon coordinated development and promoting urban development and ecological harmony.
The Effect of Transactional Leadership on Organizational Agility in Tourism and Hospitality Businesses: The Mediating Roles of Organizational Trust and Ambidexterity
Authors: Khairy Hazem Ahmed , Baquero Asier , Al-Romeedy Bassam Samir
Published: September 2023

The tourism and hospitality industry is dynamic, so it demands agility to gain a competitive edge. This paper aims to examine the effect of transactional leadership on organizational agility in the tourism and hospitality industry. It also investigates the roles of organizational trust and ambidexterity as mediators by adopting the resource-based view (RBV). This study’s data are collected from the full-time employees working in category (A) travel agencies and five-star hotels operating in Egypt. The PLS-SEM approach was used to analyze 532 valid responses using WarpPLS 7.0. The findings showed that there is a positive relationship between transactional leadership and organizational agility, as well as positive relationships between transactional leadership with organizational trust and ambidexterity. Organizational trust and ambidexterity were also found to have positive relationships with organizational agility. Moreover, the findings revealed that organizational trust and ambidexterity play a mediating role between transactional leadership and organizational agility. According to the results, setting specific, measurable, achievable, relevant, and time-bound (SMART) goals is a key aspect of transactional leadership. Managers can collaborate with employees to set goals aligned with organizational agility, encouraging them to proactively identify and seize opportunities.
Spatial Distribution and Influencing Factors of High-Level Tourist Attractions in China: A Case Study of 9296 A-Level Tourist Attractions
Authors: Zikirya Bahram , Zhou Chunshan
Published: September 2023

The distribution pattern of high-level tourist attractions is crucial for the sustainable development of the tourism industry. However, few studies have explored the spatial distribution and dominant influencing factors of tourist attractions of different levels from a macro perspective in China. This study, which was based on large-scale multi-source data, involved the use of kernel density analysis, local spatial autocorrelation, and geographical detector analysis to explore the spatial distribution, spatial correlation, and dominant influencing factors of high-level tourist attractions in China. The study’s results show that the spatial distribution of tourist attractions of different levels is polarized and regionally clustered, and there exist some spatial correlation effects among attractions of the same level. Additionally, different influencing factors play a different role in determining the spatial distribution of attractions of different levels. Based on market demand and tourism resources, it is necessary to regulate attractions of different levels to promote the sustainable development of high-level tourist attractions and provide a reference for the development of China’s tourism industry.
Transit f(Q,T) Gravity Model: Observational Constraints with Specific Hubble Parameter
Authors: Kale A. P. , Solanke Y. S. , Shekh S. H. , Pradhan A.
Published: September 2023

The present analysis deals with the study of the f(Q,T) theory of gravity, which was recently considered by many cosmologists. In this theory of gravity, the action is taken as an arbitrary function f(Q,T), where Q is non-metricity and T is the trace of the energy–momentum tensor for matter fluid. In this study, we took two different forms of the function f(Q,T) as f(Q,T)=a1Q+a2T and f(Q,T)=a3Q2+a4T, and discussed the physical properties of the models. Also, we obtained the various cosmological parameters for the Friedmann–Lemaître–Robertson–Walker (FLRW) universe by defining the transit form of a scale factor that yielded the Hubble parameter in redshift form, as H(z)=H0(λ+1)λ+(1+z)δ. We obtained the best-fit values of model parameters using the least squares method for observational constraints on available datasets, like Hubble H(z), Supernova SNe-Ia, etc., by applying the root mean squared error formula (RMSE). For the obtained approximate best-fit values of model parameters, we observed that the deceleration parameter q(z) shows a signature-flipping (transition) point within the range of 0.623≤z0≤1.668. Thus, it shows the decelerated expansion transiting into the accelerated universe expansion with ω→−1 as z→−1 in the extreme future.
A Green’s Function Based Iterative Approach for Solutions of BVPs in Symmetric Spaces
Authors: Ahmad Junaid , Arshad Muhammad , Hussain Aftab , Al Sulami Hamed
Published: September 2023

We consider the Banach space C[0,1], which is a symmetric Banach space, and prove the existence and approximation of numerical solutions for a broad class of third-order BVPs. Our approach is based on an integral operator that is constructed using Green’s function. The Banach contraction principle (BCP) is applied to guarantee a unique solution to our problem. Moreover, in order to find the value of the numerical solution, this new operator is embedded within the three-step Noor iterative scheme; we named this new iterative scheme the Noor–Green iterative scheme. We provide a convergence theorem for the proposed scheme by employing suitable restrictions on the parameters involved in the problem and in the scheme. The results of the stability of our scheme are also reported. It is worth mentioning that unlike the concept of stability in the classical sense, our result for stability is based on the concept of weak w2 stability. In order to support our findings, we carried out various numerical experiments using different third-order BVPs. Finally, we report on the application of our iterative scheme to solve a class of fractional BVPs in the same symmetric Banach space. Our results are essentially new in the present literature and extend several of the results found in the current literature.
A Scalar Product for Computing Fundamental Quantities in Matter
Authors: Fernandez-Corbaton Ivan , Vavilin Maxim
Published: September 2023

We introduce a systematic way to obtain expressions for computing the amount of fundamental quantities such as helicity and angular momentum contained in static matter, given its charge and magnetization densities. The method is based on a scalar product that we put forward which is invariant under the ten-parameter conformal group in three-dimensional Euclidean space. This group is obtained as the static restriction (frequency ω=0) of the symmetry group of Maxwell equations: The fifteen-parameter conformal group in 3+1 Minkowski spacetime. In an exemplary application, we compute the helicity and angular momentum squared stored in a magnetic Hopfion.
Target-Network Update Linked with Learning Rate Decay Based on Mutual Information and Reward in Deep Reinforcement Learning
Authors: Kim Chayoung
Published: September 2023

In this study, a target-network update of deep reinforcement learning (DRL) based on mutual information (MI) and rewards is proposed. In DRL, updating the target network from the Q network was used to reduce training diversity and contribute to the stability of learning. If it is not properly updated, the overall update rate is reduced to mitigate this problem. Simply slowing down is not recommended because it reduces the speed of the decaying learning rate. Some studies have been conducted to improve the issues with the t-soft update based on the Student’s-t distribution or a method that does not use the target-network. However, there are certain situations in which using the Student’s-t distribution might fail or force it to use more hyperparameters. A few studies have used MI in deep neural networks to improve the decaying learning rate and directly update the target-network by replaying experiences. Therefore, in this study, the MI and reward provided in the experience replay of DRL are combined to improve both the decaying learning rate and the target-network updating. Utilizing rewards is appropriate for use in environments with intrinsic symmetry. It has been confirmed in various OpenAI gymnasiums that stable learning is possible while maintaining an improvement in the decaying learning rate.
A Study on the Drivers of Carbon Emissions in China’s Power Industry Based on an Improved PDA Method
Authors: Wei Hu , Zhan Tian , Yi Zhang , Shuo Wang , Yan Li
Published: September 2023

The power industry is a major source of carbon emissions in China. In order to better explore the driving factors of carbon emissions in China’s power industry and assist the Chinese government in formulating emission reduction strategies for the power industry, this study applies the improved production-theoretical decomposition analysis (PDA) method to analyze the carbon emission drivers of China’s power industry. This study investigates the impact of energy intensity, per capita GDP, population density, power generation structure, and environmental climate on carbon emissions in China’s power industry in 30 provinces from 2005 to 2020. It was found that the carbon emission ratios of the power sector in all provinces and cities are basically greater than 1, which indicates that carbon emissions in most of the power sectors in the country are still increasing as of 2020. Overall, the effects of potential thermal fuel carbon emission efficiency, potential thermal energy consumption efficiency, the carbon emission efficiency of thermal power generation, economic scale, population density, and annual rainfall change are mostly greater than 1 and will promote the growth of carbon emissions in the power sector. Moreover, the effects of thermal power generation energy efficiency technology, thermal power generation emission reduction technology, power generation structure, and power generation per unit GDP are mostly less than 1 and will inhibit the growth of carbon emissions in the power sector. However, each of these drivers does not have the same degree of influence and impact effect for each province and city. Based on the research results, some policy recommendations are proposed.
Thermal Effects in Ising Cosmology
Authors: Irges Nikos , Kalogirou Antonis , Koutroulis Fotis
Published: September 2023

We consider a real scalar field in de Sitter background and compute its thermal propagators. We propose that in a dS/CFT context, nontrivial thermal effects as seen by an ‘out’ observer can be encoded in the anomalous dimensions of the d=3 Ising model. One of these anomalous dimensions, the critical exponent η, completely fixes a number of cosmological observables, which we compute.
Novel Potent Autophagy Inhibitor Ka-003 Inhibits Dengue Virus Replication
Authors: Limthongkul Jitra , Akkarasereenon Kornkamon , Yodweerapong Tanpitcha , Songthammawat Poramate , Tong-Ngam Pirut , Tubsuwan Alisa , Kunkaew Nawapol , Kanjanasirirat Phongthon , Khumpanied Tanawadee , Wannalo Warawuth , Ubol Sukathida , Borwornpinyo Suparerk , Ploypradith Poonsakdi , Ponpuak Marisa
Published: September 2023

Every year, dengue virus (DENV) affects millions of people. Currently, there are no approved drugs for the treatment of DENV infection. Autophagy is a conserved degradation process that was shown to be induced by DENV infection and required for optimal DENV replication. The modulation of autophagy is, therefore, considered an attractive target to treat DENV infection. This study carried out a high-content image screen analysis using Crispr-Cas9 GFP-LC3 knocked-in HeLa cells of a compound library synthesized from or inspired by natural products and their biocongener precursors to discover novel autophagy inhibitors. The screen identified Ka-003 as the most effective compound for decreasing the number of autophagic vacuoles inside cells upon autophagy induction. Ka-003 could inhibit autophagy in a dose-dependent manner at low micromolar concentrations. More importantly, Ka-003 demonstrated the concentration-dependent inhibition of DENV production in Crispr-Cas9 GFP-LC3 knocked-in THP-1 monocytes. The core structure of Ka-003, which is a methyl cyclohexene derivative, resembles those found in mulberry plants, and could be synthetically prepared in a bioinspired fashion. Taken together, data indicate that Ka-003 hampered autophagy and limited DENV replication. The low cytotoxicity of Ka-003 suggests its therapeutic potential, which warrants further studies for the lead optimization of the compound for dengue treatment.
Trend of HPV Molecular Epidemiology in the Post-Vaccine Era: A 10-Year Study
Authors: Lin Yueh , Lin Wan-Ying , Lin Ting-Wei , Tseng Yi-Ju , Wang Yu-Chiang , Yu Jia-Ruei , Chung Chia-Ru , Wang Hsin-Yao
Published: September 2023

Cervical cancer, a major health concern among women worldwide, is closely linked to human papillomavirus (HPV) infection. This study explores the evolving landscape of HPV molecular epidemiology in Taiwan over a decade (2010–2020), where prophylactic HPV vaccination has been implemented since 2007. Analyzing data from 40,561 vaginal swab samples, with 42.0% testing positive for HPV, we reveal shifting trends in HPV genotype distribution and infection patterns. The 12 high-risk genotypes, in order of decreasing percentage, were HPV 52, 58, 16, 18, 51, 56, 39, 59, 33, 31, 45, and 35. The predominant genotypes were HPV 52, 58, and 16, accounting for over 70% of cases annually. The proportions of high-risk and non-high-risk HPV infections varied across age groups. High-risk infections predominated in sexually active individuals aged 30-50 and were mixed-type infections. The composition of high-risk HPV genotypes was generally stable over time; however, HPV31, 33, 39, and 51 significantly decreased over the decade. Of the strains, HPV31 and 33 are shielded by the nonavalent HPV vaccine. However, no reduction was noted for the other seven genotypes. This study offers valuable insights into the post-vaccine HPV epidemiology. Future investigations should delve into HPV vaccines’ effects and their implications for cervical cancer prevention strategies. These findings underscore the need for continued surveillance and research to guide effective public health interventions targeting HPV-associated diseases.
Cost-Effectiveness of Sustainable Agricultural Water Policies: Source Switching versus Irrigation Buyout Auctions in Georgia’s Lower Flint River Basin
Authors: Mullen Jeffrey D. , Niu Yizhou
Published: September 2023

In this paper, a new methodology for comparing the cost-effectiveness of sustainable agricultural water policies during times of drought is developed. The methodology explicitly accounts for regional economic impacts from policy implementation and uncertainty related to drought frequency. The methodology is applied to two policy options being considered by the state of Georgia in the lower Flint River basin: irrigation buyout auctions and source switching. The results demonstrate the following: (1) the importance of modeling uncertainty associated with both the frequency and timing of drought, and the hydrologic effects of source switching; (2) as the frequency of drought increases, the cost-effectiveness of irrigation buyout auctions decreases. Failure to incorporate the regional economic impacts of each policy significantly underestimates the costs of both, but more so for irrigation buyout auctions than source switching. The ability to proactively manage the uncertainty associated with source switching through research and the judicious site selection of new irrigation wells increases its cost-effectiveness.
The Optimization of Water Storage Timing in Upper Yangtze Reservoirs Affected by Water Transfer Projects
Authors: Wen Fan , Guan Wenhai , Yang Mingxiang , Cao Jixue , Zou Yibo , Liu Xuan , Wang Hejia , Dong Ningpeng
Published: September 2023

To alleviate regional disparities in water resource distribution and consequent scarcity, China has initiated and planned a series of inter-basin water transfer projects using the Yangtze River Basin as the source. These projects are expected to divert approximately 33.4 billion cubic meters of water annually from the Yangtze River Basin. The implementation of these water transfer projects will inevitably alter the hydrological conditions in the upper reaches of the Yangtze River, impacting the reservoir storage strategies of cascading hydroelectric stations under current end-of-flood-season operational plans. This study quantitatively assesses the impact of water transfer projects on end-of-flood-season reservoir storage in cascading systems using the reservoir fullness ratio as an indicator. Employing reservoir storage analysis models, optimization techniques, and flood risk assessment methods, we simulated reservoir storage processes to evaluate associated flood risks and derive an optimized timing strategy for cascading reservoir storage. The results indicate that advancing the reservoir filling schedule by five days for both the Baihetan and Three Gorges dams can offset the adverse impacts of water transfer projects on reservoir storage efficiency. This adjustment restores the reservoir fullness ratio to levels observed in scenarios without water transfers while still meeting flood control requirements. After optimizing the timing of reservoir filling, the electricity generation capacity for the Baihetan and Three Gorges dams increased by 1.357 and 3.183 billion kWh, respectively, under non-transfer scenarios. In water transfer scenarios, the electricity generation for the Baihetan and Three Gorges dams increased by 1.48 and 2.759 billion kWh, respectively. By optimizing reservoir filling schedules, we not only improved the reservoir fullness ratio but also enhanced the electricity generation efficiency of the cascading systems, offering valuable insights for future reservoir operation optimization.
Cloud Modelling of Property-Level Flood Exposure in Megacities
Authors: Iliadis Christos , Glenis Vassilis , Kilsby Chris
Published: September 2023

Surface water flood risk is projected to increase worldwide due to the growth of cities as well as the frequency of extreme rainfall events. Flood risk modelling at high resolution in megacities is now feasible due to the advent of high spatial resolution terrain data, fast and accurate hydrodynamic models, and the power of cloud computing platforms. Analysing the flood exposure of urban features in these cities during multiple storm events is essential to understanding flood risk for insurance and planning and ultimately for designing resilient solutions. This study focuses on London, UK, a sprawling megacity that has experienced damaging floods in the last few years. The analysis highlights the key role of accurate digital terrain models (DTMs) in hydrodynamic models. Flood exposure at individual building level is evaluated using the outputs from the CityCAT model driven by a range of design storms of different magnitudes, including validation with observations of a real storm event that hit London on the 12 July 2021. Overall, a novel demonstration is presented of how cloud-based flood modelling can be used to inform exposure insurance and flood resilience in cities of any size worldwide, and a specification is presented of what datasets are needed to achieve this aim.
Enhanced Soil Moisture Retrieval through Integrating Satellite Data with Pedotransfer Functions in a Complex Landscape of Ethiopia
Authors: Teferi Ermias , O’Donnell Greg , Kassawmar Tibebu , Mersha Berihun D. , Ayele Gebiaw T.
Published: September 2023

Remotely sensed soil moisture products potentially provide a valuable resource for monitoring agricultural drought and assessing food security. The agriculture dominated countries of Eastern Africa experience high inter-annual variability of rainfall, but the monitoring and assessment of the predominantly rainfed agriculture systems is hindered by an absence of ground-based observations. This study evaluates the accuracy of three soil moisture products: ASCAT SWI 12.5 km, SMAP soil moisture data 9 km (SPL3SMP_E), and enhanced surface soil moisture map derived through integrating ASCAT SWI and Pedotransfer Functions (PTFs) (ASCAT_PTF_SM), in Ethiopia, through comparison with in situ-observed soil moisture datasets. Additionally, a new water retention PTF, developed for Ethiopian soils, is integrated with a high-resolution soil property dataset to enhance the spatial resolution of the soil moisture product. The results show that the new integrated dataset performs better in terms of unbiased root mean square error (ubRMSE = 0.0398 m3/m3) and bias (0.0222 m3/m3) in comparison with ASCAT SWI 12.5 km (ubRMSE = 0.0.0771 m3/m3, bias = 0.1065 m3/m3). SMAP is found to have limitations during the wet season, overestimating soil moisture. The finer spatial resolution of the data allows for a better depiction of heterogeneity of soil moisture across the landscape and can be used to identify water-related issues and improve hydrological models for agricultural water management.
Numerical Study on the Effect of Crown Clearance Thickness on High-Head Pump Turbines
Authors: Li Lei , Yan Dandan , Liu Xuyang , Zhao Weiqiang , Wang Yupeng , Pang Jiayang , Wang Zhengwei
Published: September 2023

In order to promote the development of new power systems and the consumption of clean energy, pumped storage hydropower stations tend to become increasingly larger in capacity and higher in head height. In this paper, a three-dimensional model of the full channel of a high-head pump turbine is established, and the influence of the gap thickness between the runner crown and the headcover on the internal flow field characteristics, pressure fluctuation characteristics and axial water thrust are studied by means of computational fluid dynamics (CFD). The results indicate that the area where the pressure and velocity vary greatly in the flow field of the crown clearance is at the seal of the labyrinth ring. In addition, the pressure balance pipe has a greater impact on the pressure and flow rate of the water passing through the clearance, and the crown clearance near the pressure balance pipe generates a vortex, resulting in energy loss. Decreasing the thickness of the clearance has no obvious effect on the pressure on the flow-passing components, and increasing the thickness of the clearance has a great change in the pressure values at the upper crown inlet, in front of the labyrinth ring of the crown and in front of the labyrinth ring of the band. The upper part of the vaneless area, the crown inlet and the lower ring inlet are close to the runner; hence, the interference from the rotating parts is the strongest. The effect of increasing the thickness of the crown clearance on the axial water thrust is greater than that of decreasing the thickness of the crown clearance. The pulsation frequency of the axial thrust on the crown, band and blade and the resultant force of the axial thrust increase with the increase in the crown clearance thickness.
Re-Establishing Naturally Reproducing Sturgeon Populations in the Caspian Basin: A Wicked Problem in the Ural River
Authors: Pueppke Steven G. , Nurtazin Sabir T. , Murzashev Turesh K. , Galymzhanov Islam S. , Graham Norman A. , Konysbayev Talgarbay
Published: September 2023

Although Eurasia’s Caspian basin once supported the world’s richest and most diverse complex of sturgeon species, recent human activities have decimated populations of these ecologically and economically important fish. All five anadromous Caspian sturgeon species are critically endangered, and the potamodromous sterlet is also threatened. The precipitous decline of these species is due to a combination of factors that includes illegal, unreported, and unregulated (IUU) fishing; destruction of feeding and spawning habitat; water pollution; and the environmental consequences of climate change. International efforts are currently underway to re-establish sustained naturally reproducing sturgeon populations in the basin. Here, we update and review the status of sturgeon in the Caspian Sea with emphasis on the northern basin and the inflowing Volga and Ural rivers. We then focus on efforts to restore sturgeon in the Ural, which originates in Russia and flows through Kazakhstan before entering the Caspian Sea. With nearly ideal hydrological conditions for sturgeon, the Ural is the basin’s sole remaining river that allows migrating sturgeon unimpeded access to potentially productive spawning grounds. The challenge of re-establishing sturgeon in the Ural River exhibits the classical characteristics of wicked problems: ambiguous definitions, changing assumptions and unanticipated consequences, tradeoffs and economic dependencies, an incomplete and contradictory knowledge base, and no straightforward pathway toward a final solution. This challenge is examined here for the first time from the perspective of its wicked dynamics, with consideration given to approaches that have proven effective elsewhere in resolving wicked environmental problems.
Quantifying Household Water Use and Its Determinants in Low-Income, Water-Scarce Households in Karachi
Authors: Khan Hassaan Furqan , Arif Muhammad Ali , Intikhab Sara , Arshad Syed Ali
Published: September 2023

Water system investments in megacities in South Asia are driven by a perceived ‘shortage’ of water supply compared to water demand. However, water demand estimates for such cities often do not reflect local socioeconomic and demographic characteristics nor account for seasonal variability. In this study, using a mixed-methods approach, we quantify household water use and its determinants and assess the seasonality of access to piped water in the low-income, water-scarce township of Lyari in Karachi. Results from over 600 household surveys show that the reported per capita water usage at the household level is lower than the assumed water demand by the city’s water utility. Water use is found to differ by gender, season, and economic status. More affluent households are able to “purchase” water security and sustain higher water use even in situations of extreme water scarcity. The perceived sufficiency of water supply improves markedly in the winter despite no increase in supply, indicating reduced demand. These findings can inform more accurate water demand projections for Karachi and highlight the importance of accounting for local socioeconomic and environmental contexts in water demand projections.
An Improved Xin’anjiang Hydrological Model for Flood Simulation Coupling Snowmelt Runoff Module in Northwestern China
Authors: Tan Yaogeng , Dong Ningpeng , Hou Aizhong , Yan Wei
Published: September 2023

The Xin’anjiang hydrological model (XHM) is the practical tool for runoff simulation and flood forecasting in most regions in China, but it still presents some challenges when applied to Northwest China, where the river runoff mostly comes from high-temperature snowmelt, as the model lacks such a functional module. In this study, the improved XHM coupling snowmelt module is presented to complete the existing XHM for better suitability for flood simulation in areas dominated by snowmelt. The improved model includes four sub-models: evapotranspiration, runoff yield, runoff separation, and runoff routing, where the snowmelt runoff module is introduced in both the runoff yield and separation sub-models. The watershed is divided into two types, non-snow areas with lower altitudes and snow-covered areas with higher altitudes, to study the mechanism of runoff production and separation. The evaluation index, determination coefficients (R2), mean square error (MSE), and Nash efficiency coefficients (NSE) are used to assess the improved XHM’s effect by comparing it with the traditional model. Results show that the R2 of the improved XHM coupled with snowmelt are around 0.7 and 0.8 at the Zamashk and Yingluoxia stations, respectively, while the MSE and NSE are also under 0.4 and above 0.6, respectively. The absolute value of error of both flood peaks in the Yingluoxia station simulated by improved XHM is only 10% and 6%, and that of traditional XHM is 32% and 40%, indicating that the peak flow and flood process can be well simulated and showing that the improved XHM coupled with snowmelt constructed in this paper can be applied to the flood forecasting of the Heihe River Basin. The critical temperature of snow melting and degree-day factor of snow are more sensitive compared with other parameters related to snow melting, and the increasing trend of peak flow caused by both decreased critical temperature and increased degree-day factor occurs only when the value of the model’s state (snow reserve) is higher. These results can expand the application scope in snow-dominated areas of the XHM, providing certain technical references for flood forecasting and early warning of other snowmelt-dominated river basins.
Management Techniques of Ancestral Hydraulic Systems, Nasca, Peru; Marrakech, Morocco; and Tabriz, Iran in Different Civilizations with Arid Climates
Authors: Esenarro Doris , Vilchez Jesica , Adrianzen Marie , Raymundo Vanessa , Gómez Alejandro , Cobeñas Pablo
Published: September 2023

The research aims to evaluate various management techniques of Ancient Hydraulic Systems (AHS) in different civilizations in arid climates, in cities located in Nasca in Perú (Puquio), Marrakech in Marruecos (Khettara) andTabriz in Irán (Qanat). The scarcity of water resources in these areas compelled the inhabitants to seek water management solutions to meet the necessary water supply for the population at the time. The methodology employed was a case study in which climatic data, supply, and operation of AHS were analyzed. The different indicators studied resulted in findings that, in the case of Nasca, the system relied on lintels, utilizing robust materials such as stone. They employed geometry to control water flow velocity, inclined walls to prevent collapses, and terraces to facilitate access to underground galleries. In the cases of Tabriz and Marrakech, their systems were based on excavations and reinforcements primarily using clay and earth as materials. In conclusion, the techniques employed in different civilizations are responses to contextual realities, offering an adaptive solution to environmental and physical challenges with a sustainable focus within their immediate surroundings.
Divergent Geochemical Pathways of Carbonate Aquifer Evolution in a Classic Karst Terrain: (1) Polygenetic Cave Development Identified Using Longitudinal Groundwater Geochemistry
Authors: Burgess Sarah A. , Florea Lee J. , Branam Tracy D.
Published: September 2023

Carbonic acid and sulfuric acid speleogenesis describe a dichotomy between epigenetic and hypogenetic caves and carbon and sulfur cycling in karst, but do not acknowledge the global spectrum of cave formation. This paper, part one of a two-part investigation, tests and revises speleogenetic models from a classic karst landscape using dissolved ion concentrations δ13CDIC, and δ34S in water samples collected at four sites across the Bluespring and Lost River karst basins in the Mitchell Plateau, Indiana, USA. Analyses revealed elevated sulfur in both karst basins but differently sourced; H2S (δ34S = −14.2‰) evolved from petroleum seeps in Bluespring Caverns accounted for up to 61% of sulfur in the cave stream, while evaporite beds (δ34S = [+14.50‰, +17.91‰]) of the St. Louis Limestone contributed up to 100% of sulfur at Orangeville Rise, a terminal spring of the Lost River karst basin. These results have implications for carbon–sulfur cycle linkages, particularly the potential acceleration of carbon flux from sulfuric acid dissolution in otherwise epigenetic settings. We suggest a new paradigm for speleogenesis in the North American midcontinent—speleogenesis in the Mitchell Plateau and similar settings is not epigenetic or hypogenetic, but instead polygenetic with competing chemical processes varying across space and time.