Low Discharge Research Articles

Impacts of river flow and thermal regimes on fish growth dynamics during early life history

Growth during early life stages is critical to fish population persistence. Few studies explore how river discharge and thermal regimes impact growth dynamics of young-of-the-year (YOY) fishes. We used otolith biochronologies and generalised additive mixed models to partition the effects of age, individual, river, temperature, discharge, and variance in discharge on daily growth rates of YOY fishes with an opportunistic life-history strategy: Galaxias vulgaris and Gobiomorphus breviceps. Growth of both species increased with temperature. Galaxias growth decreased with discharge, while Gobiomorphus growth increased with lowered discharge but only to a point (ca. 1/3 of median discharge), after which growth plateaued. Floods had a strong negative effect on YOY growth. Our study systems and species had different characteristics to those that formed the basis of the Riverscape Recruitment Synthesis Model (RRSM) and may explain why our results were only partially consistent with flow predictions for opportunistic species of the RRSM. Further, Galaxias growth was a negative function of high-frequency, daily variation in flow, and we present testable hypotheses to explain this result.

Hepatitis B Virus-Related Cirrhosis and Hepatocellular Carcinoma Hospital Discharge Rates from 2005 to 2021 in Spain: Impact of Universal Vaccination

Background: The main consequences of chronic hepatitis B virus (HBV) infections are cirrhosis and hepatocellular carcinoma (HCC), both associated with frequent hospitalization. The aim of this study was to analyze the impact of universal HBV vaccination in Spain on chronic HBV-related hospital discharges from 2005 to 2021. Methods: Using data from the Minimum Basic Data Set of the Spanish National Health System, we calculated the hospital discharge rate ratio (HDRR) and 95% confidence interval (CI) values for chronic HBV-related discharges between 2005 and 2021. For comparative purposes, we calculated the HDRR and 95% confidence interval (CI) values for the early (2005–2013) and later (2014–2021) periods and the vaccinated compared with unvaccinated cohorts for the 20–39 age group. Results: The hospital discharge rate per 1,000,000 people was 3.08 in 2005 and 4.50 in 2021 for HCC, and 4.81 in 2005 and 1.92 in 2021 for cirrhosis. Comparing the early and later periods, values were higher for HCC (HDRR 1.13; 95% CI: 1.06–1.20) and lower for cirrhosis (HDRR 0.56; 95% CI: 0.51–0.60). The rate for the 20–39 age group was lower for the vaccinated compared with the unvaccinated cohorts overall (HDRR 0.53; 95% CI: 0.45–0.62), for HCC (HDRR 0.66; 95% CI: 0.53–0.82), and for cirrhosis (HDRR 0.41; 95% CI: 0.33–0.53). Conclusions: This study describes the important impact, after 25 years, of universal HBV vaccination in Spain: cirrhosis hospital discharge rate was reduced, and the vaccinated cohorts, compared with the unvaccinated cohorts in the 20–39 age group, had a lower hospital discharge rate of both HCC and cirrhosis.

High‐potential and Stable Bipolar Cathode for Rechargeable Batteries with Fast‐charging and Wide‐temperature Adaptability

Organic carbonyl compounds have been recognized as promising electrodes due to multiple active sites, abundant element resources and flexible structural designability, while their practical applications are still hindered by the easy solubility and low discharge potential. Herein, a novel bipolar polymer composite (TAC) was well‐designed by grafting p‐type triphenylamine units onto n‐type anthraquinone to form an extended π‐conjugated structure and in‐situ growing on carbon nanotubes, which was proved not only with higher discharge potential but also effectively suppress the dissolution issues. Moreover, TAC combined the advantages of different active sites and behaved a dual‐ion storage mechanism. Benefitting from the in‐situ polymerization process, TAC with tube‐type core‐shell structure exhibited enhanced electron transport and improved utilization of active sites, resulting in high capacity (193 mAh g‐1), outstanding rate performance (fast charging within 17 s), long‐term stability (a high capacity retention of 87% after 1000 cycles) and high mass loading (10 mg cm‐2). Additionally, TAC can well adapt to the temperature change, outputting a capacity of 72 mAh g‐1 at ‐60 °C and 165 mAh g‐1 at 80 °C. Such versatile polymer structure inspires the design of high performance organic materials for rechargeable batteries to satisfy high stability and wide temperature operations.

High-potential and Stable Bipolar Cathode for Rechargeable Batteries with Fast-charging and Wide-temperature Adaptability.

Organic carbonyl compounds have been recognized as promising electrodes due to multiple active sites, abundant element resources and flexible structural designability, while their practical applications are still hindered by the easy solubility and low discharge potential. Herein, a novel bipolar polymer composite (TAC) was well-designed by grafting p-type triphenylamine units onto n-type anthraquinone to form an extended π-conjugated structure and in-situ growing on carbon nanotubes, which was proved not only with higher discharge potential but also effectively suppress the dissolution issues. Moreover, TAC combined the advantages of different active sites and behaved a dual-ion storage mechanism. Benefitting from the in-situ polymerization process, TAC with tube-type core-shell structure exhibited enhanced electron transport and improved utilization of active sites, resulting in high capacity (193 mAh g-1), outstanding rate performance (fast charging within 17 s), long-term stability (a high capacity retention of 87% after 1000 cycles) and high mass loading (10 mg cm-2). Additionally, TAC can well adapt to the temperature change, outputting a capacity of 72 mAh g-1 at -60 °C and165 mAh g-1 at 80 °C. Such versatile polymer structure inspires the design of high performance organic materials for rechargeable batteries to satisfy high stability and wide temperature operations.

Open versus Minimally Invasive Hepatic and Pancreatic Surgery: 1-Year Costs, Healthcare Utilization and Days of Work Lost

IntroductionUtilization of minimally invasive surgery (MIS) has become increasingly popular due to its potential benefits such as earlier recovery and reduced morbidity. We sought to characterize differences in 1-year healthcare costs and missed workdays among patients undergoing MIS and open surgery for a hepatic or pancreatic indication. MethodsData on patients who underwent hepatic and pancreatic resection were obtained from the IBM Marketscan database. Generalized linear models were utilized to compare healthcare costs and missed workdays among patients undergoing MIS versus open surgery. ResultsAmong 8,705 patients, 85.0% (n=7,399) and 15.0% (n=1,306) patients underwent an open or MIS HP procedure, respectively. In the unmatched cohort, patients who underwent MIS were more likely to be female (62.7% vs. 54.6%) and were less likely to have a Charlson Comorbidity Index score >2 (34.5% vs. 49.6%) (both p<0.05). After entropy balancing, multivariable analysis revealed that MIS was associated with lower 1-year post discharge expenditures (mean difference -$9,739, 95%CI-$12,893, -$6,585) and fewer missed workdays at 1-year post-discharge (IRR 0.84, 95%CI 0.81-0.87) (all p<0.001). DiscussionAt index hospitalization and 1-year post-discharge, an HP MIS approach was associated with lower healthcare expenditures versus open surgery for hepatic and pancreatic resection, as well as fewer missed workdays.

Characterization, outcomes and time to event predictors of urinary tract infections acquired during post-acute stroke inpatient rehabilitation: A comprehensive cohort study

ObjectivesTo i) compare baseline clinical and demographic characteristics of post-acute stroke inpatients who were diagnosed with first-time urinary tract infection (UTI) vs inpatients who were not ii) compare rehabilitation outcomes between both groups and iii) examine associations between time to UTI event and risk factors. DesignRetrospective observational cohort study SettingInstitution for inpatient neurological rehabilitation. ParticipantsInpatients (n=1683) admitted within 3 months post-stroke to a rehabilitation facility between 2005 and 2023. InterventionsNot applicable. Main Outcome MeasuresFunctional Independence Measure (FIM), Functional Ambulation Categories (FAC) at admission. Cox proportional hazards models analyzed the association between UTI event timing and risk factors. ResultsOf the (n=1683) included patients, 196 (11.6%) experienced a UTI. In 32.1% of cases, the UTI occurred during the first week after admission to rehabilitation and 47.9% of UTIs occurred during the first two weeks. Median (IQR) time to UTI was 16 (5-37) days since admission. Most common germs were Escherichia coli (40.5%), Klebsiella pneumoniae (23.7%) and Pseudomonas aeruginosa (6.4%). Patients who acquired a UTI had older age, higher stroke severity, higher proportion of dysphagia, hypertension, neglect, bilateral affectation, atrial fibrillation, hemiplegia, lower levels of functional independence and lower FAC. We identified no differences in sex, type of stroke (ischemic or hemorrhagic), time to admission, aphasia, diabetes, dyslipidemia, chronic obstructive pulmonary disease, dominant side affected and educational level between both groups. Patients with UTI presented significantly poorer rehabilitation outcomes including lower discharge FIM and FAC, larger LOS, lower FIM efficiency and decreased FIM effectiveness.Multivariable Cox proportional hazards identified hypertension HR=1.60(1.13-2.27), admission FIM HR=0.98(0.97-0.99), admission BMI HR=0.96(0.93-0.99) and admitted with catheter HR= 1.80(1.22-2.64) as significant predictors of time to first UTI event (Concordance-index = 0.754). ConclusionsUTIs identification, characterization, and predictive factors can support post-acute stroke mitigation strategies to minimize UTI-related complications and optimize rehabilitation outcomes.

Safety and efficacy of cangrelor in endovascular thrombectomy compared with glycoprotein IIb/IIIa Inhibitors.

Cangrelor, an intravenous P2Y12-receptor inhibitor, is a reversible and short-acting antithrombotic medication non-inferior to irreversible glycoprotein IIb/IIIa inhibitors (GPIs) like eptifibatide. There are insufficient data to compare the medications in endovascular thrombectomies (EVTs) requiring emergent platelet inhibition. To review our institution's experience with cangrelor in EVT and compares its safety and efficacy against GPIs. A large healthcare system retrospective review identified all patients who had received cangrelor or eptifibatide intraoperatively during EVT between December 2018 and March 2023 for this cohort study. Clinical data were reviewed. Functional status was defined by the modified Rankin Scale (mRS) and National Institutes of Health Stroke Scale (NIHSS) at multiple time points. Multivariate regression was performed. Of 1010 EVT patients, 36 cangrelor and 104 eptifibatide patients were selected. There were no differences in baseline function or presentations. Cangrelor was frequently administered for stenting tandem occlusions (n=16, 44.4%), and successful reperfusion occurred in 30 (83.3%) patients. On multivariate analysis, cangrelor was associated with decreased odds of hemorrhagic conversion (adjusted OR (aOR)=0.76, P=0.004) and symptomatic hemorrhage (aOR=0.86, P=0.021). There were no differences in thrombotic re-occlusion. Cangrelor was associated with a lower 24-hour NIHSS score (7.0 vs 12.0, P=0.013) and discharge NIHSS score (3.0 vs 9.0, P=0.004). There were no differences in in-hospital mortality or length of stay. Cangrelor was associated with improved odds of favorable outcome, defined as mRS score 0-2, at discharge (aOR=2.69, P=0.001) and on 90-day follow-up (aOR=2.23, P=0.031). Cangrelor was associated with a decreased risk of hemorrhagic conversion and might lead to favorable functional outcomes for patients during hospitalization in comparison with GPIs. Prospective studies are warranted to investigate its use in EVT.

Readiness for hospital discharge on people after hip replacement surgery in Vietnam: A cross-sectional study

Background &amp; Aim: Readiness for hospital discharge is closely linked to post-operative complications, readmission rates, and the post-discharge health status of patients after hip replacement surgery. This study aimed to assess discharge readiness and identify the factors that predict it in patients undergoing hip replacement surgery. Methods &amp; Materials: This cross-sectional descriptive study included 112 patients who had undergone hip replacement surgery at Hospital X in Middle Vietnam. Participants were selected using a convenience sampling method, and data were collected within 4 hours before hospital discharge. The Readiness for Discharge Scale, developed by Weiss et al. was used to measure discharge readiness. Data analysis was conducted using SPSS 20.0 statistical software. Results: The average discharge readiness score was 6.06± 2.10, indicating a low discharge readiness level. Multivariable linear regression analysis revealed that age, living conditions, planned admission, previous admission for the same diagnosis, and length of hospital stay significantly predicted 78.5% of the variance in discharge readiness (F= 77.626, p&lt; 0.001). Among these factors, the strongest predictor was previous admission for the same diagnosis (β= 0.341, p&lt; 0.001), followed by planned admission (β= 0.324, p&lt; 0.001). Conclusion: The findings indicate that patients' readiness for discharge after hip replacement surgery remains low, with various factors influencing their readiness. Nurses caring for these patients should consider these factors to improve discharge readiness and patient outcomes.

Mitigating the Kinetic Hysteresis of Co-Free Ni-Rich Cathodes via Gradient Penetration of Nonmagnetic Silicon.

Co-free Ni-rich layered oxides are considered a promising cathode material for next-generation Li-ion batteries due to their cost-effectiveness and high capacity. However, they still suffer from the practical challenges of low discharge capacity and poor rate capability due to the hysteresis of Li-ion diffusion kinetics. Herein, based on the regulation of the lattice magnetic frustration, the Li/Ni intermixing defects as the primary origin of kinetic hysteresis are radically addressed via the doping of the nonmagnetic Si element. Meanwhile, by adopting gradient penetration doping, a robust Si-O surface structure with reversible lattice oxygen evolution and low lattice strain is constructed on Co-free Ni-rich cathodes to suppress the formation of surface dense barrier layer. With the remarkably enhanced Li-ion diffusion kinetics in atomic and electrode particle scales, the as-obtained cathodes (LiNixMn1-xSi0.01O2, 0.6≤x≤0.9) achieve superior performance in discharge capacity, rate capability, and durability. This work highlights the coupling effect of magnetic structure and interfacial chemicals on Li-ion transport properties, and the concept will inspire more researchers to conduct an intensive study.

To investigate the effect of discharge energy and addition of nano-powder on processing of micro slots using EDM assisted µ-milling operation

ABSTRACT Micro-electric Discharge-Milling (µ-ED-M) is a non-contact process that uses an electrical spark to remove the material from a submerged workpiece with an electrode in a dielectric. The present paper focuses on optimizing process energizing (Capacitor, Voltage) and process stabilizing (Tool Travel Speed, Nano-Powder) parameters for controlling the size and surface characteristics of micro-crater. The present work focuses on the effect of nano-powder concerning dimensional aspects and surface characteristics at high and low capacitance levels. A µ-slot has been generated on the copper material by a tungsten carbide electrode. The experimentation is performed with two capacitor levels and three voltage and tool travel speed levels using full factorial design technique using with and without mixing of nano-powder in dielectric. The desirability functional multi-objective optimization approach is used to analyze the MRR, TWR, Width, and Depth. Field emission scanning electron microscopy (FESEM), non-contact optical profilometer, and x-ray diffraction (XRD) techniques are used to analyze the surface morphology of machined surfaces. The ANOVA is used to optimize the results; at low discharge energy, tool travel speed contributes 41% and promotes a higher thickness of recast layer 12.7 µm, whereas high discharge energy and nano-powder concentration contribute approx.—36% with 8.56 µm of recast layer.

Association between nasogastric tube feeding and discharge outcomes in patients aged 80 and older with aspiration pneumonia: A propensity score‐matched retrospective cohort study

AbstractBackgroundThis study investigated the association between nasogastric tube feeding (NGF) and discharge rate to previous residences with oral intake in patients aged 80+ with aspiration pneumonia.MethodsA retrospective cohort study included 256 hospitalized patients with aspiration pneumonia from 2012 to 2022, which could not start oral intake within 48 h due to dysphagia. Using 1:2 matched‐pair analysis, the association of interest was examined using logistic regression analysis.ResultsNGF was associated with a lower discharge rate (odds ratio: 0.15; 95% CI: 0.05–0.46).ConclusionPatients with NGF had a lower discharge rate to previous residences with oral intake.

Mitigating the Kinetic Hysteresis of Co‐Free Ni‐Rich Cathodes via Gradient Penetration of Nonmagnetic Silicon

AbstractCo‐free Ni‐rich layered oxides are considered a promising cathode material for next‐generation Li‐ion batteries due to their cost‐effectiveness and high capacity. However, they still suffer from the practical challenges of low discharge capacity and poor rate capability due to the hysteresis of Li‐ion diffusion kinetics. Herein, based on the regulation of the lattice magnetic frustration, the Li/Ni intermixing defects as the primary origin of kinetic hysteresis are radically addressed via the doping of the nonmagnetic Si element. Meanwhile, by adopting gradient penetration doping, a robust Si−O surface structure with reversible lattice oxygen evolution and low lattice strain is constructed on Co‐free Ni‐rich cathodes to suppress the formation of surface dense barrier layer. With the remarkably enhanced Li‐ion diffusion kinetics in atomic and electrode particle scales, the as‐obtained cathodes (LiNixMn1−xSi0.01O2, 0.6≤x≤0.9) achieve superior performance in discharge capacity, rate capability, and durability. This work highlights the coupling effect of magnetic structure and interfacial chemicals on Li‐ion transport properties, and the concept will inspire more researchers to conduct an intensive study.

Two-Phase Flow Modelling Based on Roughness Surface Effect of Roller Compacted Concrete

One of the most important considerations that are interest to researchers on the stepped spillway in hydraulic structure is the location of the point at which the flow begins to transform into two phase-flow and the development of boundary layers. In this study, an unconventional rough surface was used (RCC materials), which has completely different properties from what is used in previous laboratory studies, which uses smooth surfaces in reality to represent the actual roughness of the surface. Benchmark mixes are evaluated as a reference standard concrete to determine the optimal combination proportions for RCC according to The U.S. Army Corps of Engineers Standard. A laboratory study of different models enhanced by a mathematical model CFD with VOF technics to described the two- phase interaction to investigate the location of the inception point and compare the results with the proposed equations assumed by different researchers in this topic. The results obtained from the study showed a clear effect of surface roughness on the location of the inception point and the formation of the boundary layer for laboratory models. It’s clearly found that the two-phase flow starts with closer locations than it is for conventional models and the ratios vary (10 % - 20 %) according to the discharge values (where the effect of surface roughness is evident in the low discharges compared to the high discharges in which the boundary Lear effect begins to fade.

Free-standing medium-entropy porous needle-like FeCoCuNi phosphide nanowires-formed flower clusters/carbon fiber anode with high capacity and long durability for sodium-ion batteries

The drastic volume expansion and slow sodium-ion kinetics hinder the practical application of phosphides with high specific capacity and low discharge voltage in sodium-ion batteries (SIBs). Herein, we introduced entropy configuration into nanostructures and prepared a novel free-standing, three-dimensional, porous needle-like medium-entropy Fe, Co, Cu, Ni phosphide (ME-FCCNP) nanowires-formed flower clusters/carbon fiber cloth (CFC) anode (ME-FCCNP@CFC) for SIBs. The distorted lattices caused by medium-entropy configuration provide abundant sites for sodium-ion reactions and improve the electron transfer rate. The medium-entropy effects improve the mechanical stability, while the three-dimensional networks and porous needle-like nanowires provide sufficient space for the volume expansion. These combined properties enable the ME-FCCNP@CFC electrode to exhibit a high-rate capability of 170.8 mAh g−1 at 5.0 A g−1 and deliver a specific capacity of 325.8 mAh g−1 after 2000 cycles at 2.0 A g−1, far surpassing most of reported transition-metal phosphides. Moreover, the Na3V2(PO4)3 || ME-FCCNP@CFC full cell showcases a high-energy density of 256.8 Wh kg−1 and a long cycling life (267.8 mAh g−1 at 2.0 A g−1 with a capacity retention of 83.2 % after 1000 cycles). These results provide significantly promising implications for the anode design of SIBs by employing self-supporting and medium-entropy structures.

Acute Activity Urges Predict Lower Early Weight Gain During Inpatient Treatment for Anorexia Nervosa.

Early weight gain is a primary goal in the treatment of anorexia nervosa (AN) and associated with more favorable discharge weights and clinical outcomes. Activity urges, that is, a motivational state to engage in activity, have been suspected to delay early weight gain, but their prognostic role remains barely explored. Here, we investigated whether acute (state-like) activity urges at treatment onset would predict within-person weight gain in patients with AN during the initial 2 weeks of inpatient treatment. Adults with AN from an inpatient unit (N = 53) completed an activity urges measure at treatment onset, and weight changes were monitored for the duration of their treatment. Regression analyses, controlling for admission body mass index and other patient variables (i.e., patient age and AN subtype), found that higher state activity urges were associated with lower initial weight gain. Mediation analyses showed that differences in early weight changes further linked higher activity urges at admission to lower discharge weights. An activity urge cutoff value of 2.76 for distinguishing between cases with optimal and suboptimal initial weight gain is proposed. We discuss potential mechanisms of the link between activity urges and early weight gain and the implications of activity urges as a prognostic factor for improving weight restoration during AN treatment.

Solvent Polarity‐Induced Regulation of Cation Solvation Sheaths for High‐Voltage Zinc‐Based Batteries with a 1.94 V Discharge Platform

To address the challenge of low discharge platforms (&lt;1.5 V) in aqueous zinc‐based batteries, highly concentrated salts have been explored due to their wide electrochemical window (~3 V). However, these electrolytes mainly prevent hydrogen evolution and dendrite growth at the anode without significantly enhancing voltage performance. Herein we introduce an approach by adjusting solvent polarity to regulate cation solvation sheaths in hybrid electrolytes, reducing Zn/Zn2+ oxidation potential and water activity. Through strong cation‐water coordination and hydrogen bonding between dimethylsulfoxide and water, the designed electrolyte, at a low concentration, achieves a broader electrochemical window (4 V) than conventional concentrated electrolytes. Using this electrolyte, a Zn/Zn battery showed an impressive cycle life of 4340 cycles, while a Zn/lithium manganate battery delivered a high discharge platform of over 1.9 V with exceptional cycling stability. A Zn‐based micro‐battery with a polyvinyl alcohol‐based hybrid electrolyte also achieved a record‐high discharge platform of 1.94 V. This work presents a promising strategy for developing low‐concentration electrolytes for high‐performance sustainable energy storage.

Solvent Polarity-Induced Regulation of Cation Solvation Sheaths for High-Voltage Zinc-Based Batteries with a 1.94 V Discharge Platform.

To address the challenge of low discharge platforms (<1.5 V) in aqueous zinc-based batteries, highly concentrated salts have been explored due to their wide electrochemical window (~3 V). However, these electrolytes mainly prevent hydrogen evolution and dendrite growth at the anode without significantly enhancing voltage performance. Herein we introduce an approach by adjusting solvent polarity to regulate cation solvation sheaths in hybrid electrolytes, reducing Zn/Zn2+ oxidation potential and water activity. Through strong cation-water coordination and hydrogen bonding between dimethylsulfoxide and water, the designed electrolyte, at a low concentration, achieves a broader electrochemical window (4 V) than conventional concentrated electrolytes. Using this electrolyte, a Zn/Zn battery showed an impressive cycle life of 4340 cycles, while a Zn/lithium manganate battery delivered a high discharge platform of over 1.9 V with exceptional cycling stability. A Zn-based micro-battery with a polyvinyl alcohol-based hybrid electrolyte also achieved a record-high discharge platform of 1.94 V. This work presents a promising strategy for developing low-concentration electrolytes for high-performance sustainable energy storage.

Numerical Investigation of Archimedes Screw Turbines under Low-Head Conditions

The development of screw turbines for micro-hydro power generation has garnered heightened interest lately, attributed to their capability to perform efficiently despite low head and low discharge. The present numerical work aims to evaluate the prospect of low-head water energy widely available in the Aceh region. In this region, the Archimedes Screw turbine is the most commonly used. In the present numerical study, the characteristics of the Archimedes screw turbine were studied under the constant of the head of 1 meter and the inclination angle of 30o, with the flow rate served as the varying parameter. In the simulation, a three-dimensional numerical investigation of pressure characteristics, flow velocity, and kinetic energy turbulence due to the change in the flow rates was carried out using the Navier-Stokes equations. Next, the turbulence model of K-Epsilon was also implemented. The comparisons between the experimental and the simulation results were carried out to ensure the accuracy of the simulation model, and the results indicated that the changes in flow rates have a marked influence on pressure distribution, the flow velocity field, and turbulent kinetic energy. It was found that the performance of the Archimedes double screw turbine was improved by increasing the flow rate due to the uniform distribution of pressure, flow velocity, and turbulent kinetic energy. Moreover, the optimum condition was achieved in a turbine with 8 screws. Therefore, maintaining the inflow rate is crucial as it significantly impacts the efficiency of the Archimedes Screw Turbine.

Determining the Fish Migration Patterns Based on Fish Habitat Assessment at a River Confluence

ABSTRACTMuch effort has been devoted to predicting fish migration routes to assist target species migration, and yet, fish migration science and practice remain imperfect. This study aimed to predict the migration paths of Gymnocypris przewalskii at the river confluence in the Qinghai Lake basin. The authors proposed an approach for fish migration route prediction, which involves a hydrodynamic module, a habitat model and a fish migration module. The TELEMAC‐MASCARET system was used to simulate hydrodynamic conditions and statistical analyses were carried out. During the flood season, G. przewalskii migrates downstream, whereas during the migratory season, they migrate upstream. The results indicate that flow velocity was the most significant hydrodynamic parameter affecting fish migration behaviour. The optimal flow velocity range for the target fish species was between 0.7 and 1.7 m/s. The impact of water depth was only observed in low discharge situations. Besides, the temperature plays a vital role in determining fish migration and abundance. However, the results reveal that in the morning hours, the temperature exhibits a range of 10°C to 16°C, and in the noon, the average temperature ranges from 16°C to 19°C, with a maximum temperature reaching 23°C. These temperature variations enable fish to migrate towards the tributary offering a more favourable water temperature during route selection at a river confluence. The study concludes that future research should consider incorporating the swimming capacity of the focal fish species to provide insights into fish migration patterns.

Enhanced Method for Localization of Partial Discharges in Oil-Filled Transformers Using Acoustic Emission Signals

The accurate measurement of partial discharges (PD) in power transformers is a critical component in identifying faults and planning effective maintenance strategies. Acoustic emission (AE) sensing technology is suitable for detecting partial discharges in transformers because it is less affected by external electromagnetic interference and detects PD non-invasively. This paper delves into examining the relationship between the detection intensity, the specific type of PD source, and the distance to the discharge source, using AE sensors. It was observed that AE wave intensities from corona discharges tend to be relatively strong, indicating a higher detection probability. Creepage discharges usually exhibit the next level of intensity, followed by the PD occurring in bubbles. It is considered that the intensity of the AE waves varies significantly depending on both the speed at which the discharge propagates and the medium and volume of the discharge space. Furthermore, this study has conducted experimental comparisons among three distinct methods for calculating the Time Difference of Arrival (TDOA) in localization calculations. These methods are the energy criterion, Generalized Cross-Correlation (GCC), and GCC with Phase Transformation (PHAT). The experimental results suggest that the energy criterion method is particularly effective when sensors are distributed placement around the entire tank. In contrast, the GCC-PHAT method shows greater suitability in scenarios where sensors are centralized placement in certain sections of the tank. It was clearly observed that the GCC-PHAT method, which suppresses the impact of noise and reflections, consistently achieves higher estimation accuracy in comparison to the standard GCC method. Notably, this method has shown the ability to maintain its accuracy levels even in cases of low discharge intensities. The implications of these findings are significant, as they could improve the precision and effectiveness of maintenance diagnostics in power transformers.