Article
Multidisciplinary Sciences
Vishal Singh Rawat, Thendiyath Roshni, Iacopo Carnacina
Summary: Block ramps are ecofriendly drop structures designed to ensure stability in the downstream riverbed. This study tested different stilling basin bed configurations and their effect on the stability of non-cohesive beds downstream to block ramps. Experimental results showed that changes in bed configurations can affect the critical particle densimetric Froude number, thus impacting the stability of the riverbed.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2021)
Article
Environmental Sciences
Jonas Haug, Calvin Frees, Barbara Brinkmeier, Markus Aufleger
Summary: The Bar Rack FishProtector creates an electric field in the water that is actively avoided by fish, thus increasing the retention rate of fish in experiments. Results show that applying an electrical field during the night and day significantly improves the experimental retention rate.
Article
Astronomy & Astrophysics
M. Asgari-Targhi, L. Golub, M. Hahn, N. Karna, D. W. Savin
Summary: Active regions in the inner solar corona, when observed in X-ray emission, exhibit bright hot loops surrounded by unstructured clouds. These hot clouds extend to heights of 4-5 x 10(4) km at temperatures of 2-3 MK, persisting for several days without direct connections to other large-scale structures. Plasma analysis revealed beta values generally less than unity, suggesting that magnetic fields may only partially confine these regions, potentially inhibiting flare-like instabilities.
ASTROPHYSICAL JOURNAL
(2021)
Article
Computer Science, Interdisciplinary Applications
Zhi Li, Marcelo H. Garcia
Summary: Researchers have developed a synthetic riverbed topography model for idealized meandering rivers, known as pyRiverBed, which includes a meander migration and neck cutoff submodel. This model aims at generating riverbed topography for each snapshot during the migration process and providing guidance for experiment and numerical model design. Validation results show good accuracy in predicting meander migration and neck cutoff events.
COMPUTERS & GEOSCIENCES
(2021)
Article
Chemistry, Multidisciplinary
Yongping Wu, Mingyin Liu, Panshi Xie, Hongwei Wang, Bosheng Hu
Summary: This study investigates the variations of loading, deformation, and loss in the shaft coal pocket wall in coal mines under dynamic-static load, and aims to determine the mechanical state, loss characteristics, and stability. Through innovative three-dimensional physical similarity tests and coal loading/unloading experiments, the study analyzes the deformation, pressure, surrounding rock, and flow pattern of the silo wall. The results indicate that different dispersion particles significantly impact the strain of the shaft wall, with coal particles having a higher overpressure coefficient compared to dry sand particles. The particle size and internal friction angle also greatly affect the wall deformation. The study also finds that coal particles are more prone to arching phenomenon during unloading, but the presence of warehouse wall support can reduce the occurrence of bulk arching. Additionally, the weak rock stratum in the surrounding rock plays a major role in controlling the deformation and failure development of the shaft wall. The three-dimensional physical simulation experiment effectively reproduces field engineering practice and the results are validated through numerical simulation analysis.
Article
Geography, Physical
Michele Palermo, Deep Roy, Simone Pagliara
Summary: This paper investigates the impact of protected stilling basins downstream of block ramps in curved river channels, finding that the equilibrium scour morphology is mainly dependent on hydraulic conditions and influenced by the position of protection structures in the basin. Different morphological configurations are proposed, and an empirical equation is provided to estimate the maximum scour depth under tested configurations.
Article
Engineering, Electrical & Electronic
Abdelrahman A. Ijjeh, Marylene Cueille, Jean-Lou Dubard, Michel M. Ney
Summary: This article presents a mathematical formulation for stability and dispersion analysis when using block meshing in electromagnetic devices, allowing for computation of maximum mesh size and time step to ensure a tolerable level of numerical dispersion. Numerical experiments demonstrate the advantages of the proposed approach in TLM block meshing.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2021)
Article
Quantum Science & Technology
Craig Gidney
Summary: This paper introduces stability experiments as a new benchmark method for evaluating the performance of quantum error correction systems in moving logical observables through space.
Article
Polymer Science
Alexander E. Marras, Trinity R. Campagna, Jeffrey R. Vieregg, Matthew Tirrell
Summary: Polyelectrolyte complex micelles (PCMs) are self-assembled nanoparticles formed by the associative phase separation of hydrophilic neutral-charged block copolymers and polyelectrolytes, and are effective in delivering hydrophilic payloads. This study investigates the scaling behavior of physical micelle parameters using various experimental techniques and provides specific conclusions, such as the significant increase in PCM core size with the length of the polyelectrolyte block chain, which is crucial for rational PCM design. The results are compared to existing data and theory, showing strong agreement and suggesting the generality of these laws for PCMs.
Review
Engineering, Environmental
Rakesh Kumar Chaudhary, Nayan Sharma, Zulfequar Ahmad
Summary: The paper reviews the application of block ramp technique in steep gradient streams, focusing on its effects on flow characteristics, stability, and energy dissipation. It suggests further research to improve the equations essential for design analysis. Block ramps have the potential to attenuate devastating fluvial forces in gravel-bed streams during cloud bursts.
Article
Environmental Sciences
H. J. Barneveld, E. Mosselman, V. Chavarrias, A. J. F. Hoitink
Summary: Sustainable river management can benefit from models predicting long-term morphological developments. Analytical tools provide metrics for rapid assessment of future morphological developments. This study evaluates the validity of an analytical approach based on linear stability analyses for predicting bed perturbation celerity in river systems.
WATER RESOURCES RESEARCH
(2023)
Article
Environmental Sciences
Jianqiang Xu, Yang Xue, Senjun Huang, Liyuan Zhang, Faxing Zhang
Summary: This study investigates the influence of different types of groins on flow field and river evolution, and finds that vegetation can reduce erosion. The hydrodynamic characteristics in mobile-bed experiments differ from those in fixed-bed experiments, and the improved three-dimensional groin group performs better in sediment scouring capacity and scour depth.
Article
Ecology
Paul A. Franklin, Julian Sykes, Jane Robbins, Douglas J. Booker, Sjaan Bowie, Eleanor Gee, Cindy F. Baker
Summary: Fragmentation of river systems is a major cause of freshwater biodiversity loss. This study provides a comprehensive inventory of fish passage barriers and instream structures in New Zealand, supporting the implementation of new policy objectives for river connectivity. The data reveal that at least half of New Zealand's river network is upstream of fish migration barriers. However, limitations in the data pose challenges for prioritization and decision-making regarding barrier removal or mitigation.
ECOLOGICAL INFORMATICS
(2022)
Article
Computer Science, Hardware & Architecture
Xiaoqin Feng, Jianfeng Ma, Yinbin Miao, Ximeng Liu, Kim-Kwang Raymond Choo
Summary: This article proposes a propagation-efficient protocol NefSBFT based on social characteristics for achieving system state consensus in public blockchains. The protocol achieves fast propagation, low resource consumption, and small message complexity, while also analyzing security against DDOS attacks.
IEEE TRANSACTIONS ON DEPENDABLE AND SECURE COMPUTING
(2022)
Article
Environmental Sciences
Stephanie Mueller, Catherine A. M. E. Wilson, Pablo Ouro, Joanne Cable
Summary: Hydraulic structures, such as leaky barriers, are being added to riverine systems for the purpose of harnessing renewable energy or mitigating flooding impacts. These sustainable and cost-effective wooden barriers work by slowing down surface water flow, reducing flood peaks, and attenuating downstream water flow, providing an alternative to traditional hard engineering flood risk management methods.
WATER RESOURCES RESEARCH
(2021)
Article
Remote Sensing
Martin Detert, Erika D. Johnson, Volker Weitbrecht
INTERNATIONAL JOURNAL OF REMOTE SENSING
(2017)
Editorial Material
Environmental Sciences
Fabian Friedl, Volker Weitbrecht
INTERNATIONAL JOURNAL OF SEDIMENT RESEARCH
(2017)
Article
Engineering, Civil
Fabian Friedl, Josef Schneider, Florian Hinkelammert, Volker Weitbrecht
JOURNAL OF HYDRAULIC RESEARCH
(2018)
Article
Environmental Sciences
M. Detert, L. Kadinski, V Weitbrecht
INTERNATIONAL JOURNAL OF SEDIMENT RESEARCH
(2018)
Article
Environmental Sciences
Fabian Friedl, Volker Weitbrecht, Robert M. Boes
INTERNATIONAL JOURNAL OF SEDIMENT RESEARCH
(2018)
Article
Engineering, Civil
Isabella Schalko, Lukas Schmocker, Volker Weitbrecht, Robert M. Boes
JOURNAL OF HYDRAULIC ENGINEERING
(2018)
Article
Engineering, Civil
Isabella Schalko, Lukas Schmocker, Volker Weitbrecht, Robert M. Boes
JOURNAL OF HYDRAULIC ENGINEERING
(2018)
Article
Environmental Sciences
B. Hohermuth, V. Weitbrecht
WATER RESOURCES RESEARCH
(2018)
Article
Environmental Sciences
I. Schalko, C. Lageder, L. Schmocker, V. Weitbrecht, R. M. Boes
WATER RESOURCES RESEARCH
(2019)
Article
Environmental Sciences
I. Schalko, C. Lageder, L. Schmocker, V. Weitbrecht, R. M. Boes
WATER RESOURCES RESEARCH
(2019)
Article
Engineering, Civil
Isabella Schalko, Lukas Schmocker, Volker Weitbrecht, Robert M. Boes
JOURNAL OF HYDRAULIC RESEARCH
(2020)
Article
Environmental Sciences
Isabella Schalko, Lukas Schmocker, Volker Weitbrecht, Robert M. Boes
ENVIRONMENTAL FLUID MECHANICS
(2020)
Article
Engineering, Civil
Liekai Cao, Volker Weitbrecht, Danxun Li, Martin Detert
Summary: A new technique called AFMV uses feature matching for airborne river surface flow measurement, showing almost equal quality to PIV in velocity measurement but outperforming 3D photogrammetry in computational power. This method has the potential to provide almost real-time measurements of airborne river surface flow.
JOURNAL OF HYDRAULIC RESEARCH
(2021)
Article
Environmental Sciences
C. Rachelly, F. Friedl, R. M. Boes, V. Weitbrecht
Summary: The study investigates the effects of periodic and episodic sediment replenishment on channel bed response of a gravel-bed river, finding that sediment supply level and flow discharge exert the strongest control over channel response, while the influence of grain size distribution of replenished material is minor. Sediment replenishment can increase availability of clean gravel patches in rivers, but does not address the general shortage of shallow habitats for grayling fry and juveniles.
WATER RESOURCES RESEARCH
(2021)
Article
Engineering, Civil
Isabella Schalko, Volker Weitbrecht
Summary: Semi-permeable sediment traps are designed to retain sediment during large floods and enable sediment transport continuity during ordinary floods, but the transportation of large wood (LW) may affect the design of the inclined bar screen and reduce sediment transport. Initial experiments show that a LW volume blocking 20% of the flow cross-section is enough to decrease sediment transport by 50%, indicating that LW volume is a crucial parameter for the design of inclined bar screens. Ideas for future research to separate LW and sediment locally are suggested.
JOURNAL OF HYDRAULIC RESEARCH
(2022)
