Review
Fisheries
Subha M. Roy, Mohammad Tanveer, Rajendra Machavaram
Summary: The growing population, mechanization, urbanization, and modern agricultural operations are causing water scarcity and pollution in aquaculture. Aeration, particularly gravity aeration, is an effective method to improve dissolved oxygen in water bodies. This study aims to provide a comprehensive review of gravity aeration systems and compare their economic feasibility with other aeration practices.
AQUACULTURE INTERNATIONAL
(2022)
Article
Geosciences, Multidisciplinary
Miles M. P. Couchman, Bethan Wynne-Cattanach, Matthew H. Alford, Colm-cille P. Caulfield, Rich R. Kerswell, Jennifer A. MacKinnon, Gunnar Voet
Summary: Understanding how ocean turbulence transports heat is crucial for global circulation models. A new data-driven approach using unsupervised machine learning was presented for identifying distinct regions of turbulent mixing within a microstructure dataset. Applied to data collected near the Velasco Reef in Palau, the algorithm revealed spatial and temporal correlations between mixing characteristics and various environmental factors. Unsupervised machine learning has the potential to advance community understanding of turbulent mixing patterns globally.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Sung Hyuk Park, Bill Batchelor, Arnab Ghosh
Summary: A novel multistage vortex aerator (MVA) was developed to enhance the oxygen transfer rate and efficiency by increasing the gas-liquid interfacial area. A gas transfer model based on mass and molar balances was successfully used to simulate the dissolved oxygen change inside the aerator.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Energy & Fuels
Chaowanan Jamroen, Ponkanok Kotchprapa, Sirachat Chotchuang, Rathaphong Phoket, Pokkrong Vongkoon
Summary: Paddlewheel aerators are commonly used in aquaculture to increase dissolved oxygen (DO) in pond water. However, in remote areas without electrical network connection, they are sometimes driven by a diesel generator, which releases carbon monoxide (CO) and increases operational costs. This study proposes using a photovoltaic (PV) energy source with battery energy storage (BES) to power a paddlewheel aerator continuously. The results show that the proposed aerator achieved a 10.91% higher DO performance compared to a standalone PV-powered paddlewheel aerator without BES.
Article
Oceanography
Ajitha Cyriac, Helen E. Phillips, Nathaniel L. Bindoff, Huabin Mao, Ming Feng
Summary: This study investigates the spatiotemporal variability of turbulent mixing in the eastern south Indian Ocean. Elevated mixing is observed in the upper ocean, over bottom topography, and in mesoscale eddies. Cyclonic eddies contribute to turbulent mixing in the depth range of 500-1000 m, while anticyclonic eddies enhance mixing due to trapped near-inertial waves.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2021)
Article
Environmental Sciences
Arnab Ghosh, Mijeong Choi, Dain Yoon, Sunghoon Kim, Jaebum Kim, Jurng-Jae Yee, Sunghyuk Park
Summary: This study reports the successful restoration of a polluted urban stream using the multistage vortex aerator (MVA), an in-line mixer device that improves dissolved oxygen concentration and accelerates water purification rate. Field experiments demonstrated enhanced dissolved oxygen levels up to 7.05 mg/L and improved water quality to a good grade. The MVA process also effectively eliminated complex odors and improved water quality grades by more than two grades on average. Monitoring of stream water quality indicators revealed high removal rates of total phosphorous (56.4%) and suspended solids (61%).
Article
Fisheries
Guang Yin, Muk Chen Ong, Jihoon Lee, Taeho Kim
Summary: Dissolved oxygen is a crucial indicator for water quality and fish survival in aquaculture. Modern numerical models can be used to predict the distribution of dissolved oxygen in water, allowing for the evaluation and maintenance of water quality.
Article
Environmental Sciences
Yoichi Sato, Gregory N. Nishihara, Atsuko Tanaka, Dominic F. C. Belleza, Azusa Kawate, Yukio Inoue, Kenjiro Hinode, Yuhei Matsuda, Shinichiro Tanimae, Kandai Tozaki, Ryuta Terada, Hikaru Endo
Summary: The important role of vegetated ecosystems in carbon sequestration has attracted interest, and there is growing interest in applying knowledge of carbon capture rates to seaweed farming. This study investigated seaweed farms in Japan, comparing their autotrophic days and carbon capture rates with natural ecosystems and a degraded site. The results showed variations in autotrophy and carbon capture rates among different seaweed farms, with the Undaria pinnatifida farm in Matsushima Bay capturing the most carbon.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Agricultural Engineering
Mehmet Ali Dayioglu
Summary: This study designed a solar-powered venturi aeration system and determined its flow characteristics and operational performance parameters through experiments. The results showed that the system was capable of effectively transferring oxygen in the pool.
AQUACULTURAL ENGINEERING
(2022)
Article
Environmental Sciences
Ruijie Ye, Xiaodong Shang, Wei Zhao, Chun Zhou, Qingxuan Yang, Zichen Tian, Yongfeng Qi, Changrong Liang, Xiaodong Huang, Zhiwei Zhang, Shoude Guan, Jiwei Tian
Summary: This study reveals the prominent multihump structure of bottom-intensified turbulent diffusivity in the upslope direction of a seamount in the South China Sea using full-depth fine-resolution microstructure and hydrographic profiles. Numerical experiments suggest that this multihump bottom-intensified turbulent mixing can lead to multiple locally strengthened circulations consisting of upwelling (downwelling) motions in (above) the bottom boundary layer that are induced by bottom convergence (divergence) of the turbulent buoyancy flux. Accompanied by cyclonic (anticyclonic) flow, a three-dimensional spiral circulation manifests around the seamount topography.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Oceanography
Manuel O. Gutierrez-Villanueva, Teresa K. Chereskin, Janet Sprintall, John A. Goff
Summary: Radiation and breaking of internal lee waves in the Southern Ocean have been studied to understand their role in the energy and heat budget. This study estimated the linear lee-wave energy radiation and local dissipation using a time series of stratification and near-bottom currents. The results showed that most of the lee-wave energy radiation occurred in the Polar Front Zone of the Antarctic Circumpolar Current (ACC), and both baroclinic and barotropic instabilities influenced the conversion to lee waves in this region. The study also found that the local dissipation of lee-wave energy was less than 10%, which is contrary to previous numerical predictions.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Environmental Sciences
Jianping Xu, Yishuai Du, Guogen Su, Hexiang Wang, Jiawei Zhang, Huiqin Tian, Li Zhou, Tianlong Qiu, Jianming Sun
Summary: This study investigated the variation pattern of dissolved oxygen in an aquaculture system and established models to achieve efficient management. The findings provide a theoretical basis and novel methods for dissolved oxygen management in RAS.
Article
Fisheries
Xiao Wan, Shunyao Jiang, Qinxue Xiong, Jun R. Yang, Sujing Xia, Qihang Chen
Summary: Thermal stratification and mixing affect the vertical distribution of dissolved oxygen in water, and water temperature, chlorophyll a, and phytoplankton abundance play important roles in the vertical distribution of dissolved oxygen.
ISRAELI JOURNAL OF AQUACULTURE-BAMIDGEH
(2022)
Review
Engineering, Environmental
Daoliang Li, Mi Zou, Lingwei Jiang
Summary: This review examines various dissolved oxygen (DO) control strategies proposed by researchers worldwide in the past 20 years, focusing on the determination and control of DO concentrations in wastewater treatment plants. The strategies are categorized into classical control, advanced control, intelligent control, and hybrid control. The review also discusses the prediction and control strategies of DO concentrations in aquaculture, and provides a critical discussion on DO control.
WATER SCIENCE AND TECHNOLOGY
(2022)
Article
Engineering, Civil
Xia Shen, Sheng Li, Shikun Sun, Dengke Qing, Dehong Li, Kai Wang, Weizheng Gao, Liwei Cao
Summary: This study constructed a 3D hydrodynamic model to investigate the transport mechanism of dissolved oxygen at river confluences. The study found that the distribution of reoxygenation and the pattern of dissolved oxygen transport at the confluence exhibit specific characteristics. The flow ratio and junction angle have significant influences on the transport of dissolved oxygen.
JOURNAL OF HYDROLOGY
(2023)
Article
Mathematics, Interdisciplinary Applications
Takeshi Akinaga, Tomoaki Itano, Sotos Generalis
CHAOS SOLITONS & FRACTALS
(2016)
Article
Physics, Fluids & Plasmas
Hiroyuki Shichi, Hiroshi Yamashita, Junji Seki, Tomoaki Itano, Masako Sugihara-Seki
PHYSICAL REVIEW FLUIDS
(2017)
Article
Biophysics
Takahiro Sasaki, Junji Seki, Tomoaki Itano, Masako Sugihara-Seki
Article
Mechanics
Saki Nakayama, Hiroshi Yamashita, Takuya Yabu, Tomoaki Itano, Masako Sugihara-Seki
JOURNAL OF FLUID MECHANICS
(2019)
Article
Mechanics
Taishi Inagaki, Tomoaki Itano, Masako Sugihara-Seki
Article
Physics, Fluids & Plasmas
Hiroshi Yamashita, Tomoaki Itano, Masako Sugihara-Seki
PHYSICAL REVIEW FLUIDS
(2019)
Article
Biophysics
Masako Sugihara-Seki, Tenki Onozawa, Nozomi Takinouchi, Tomoaki Itano, Junji Seki
Article
Physics, Multidisciplinary
Tomoaki Itano
Summary: A dynamical model was developed to clarify the counterintuitive phenomena observed in freefall experiments, involving a vertically falling train of one-dimensional rigid segments hitting an inelastic horizontal plate in three-dimensional space. The model showed that the train falls faster than a particle in freefall, with the bend angle between successive chain links having a significant impact on acceleration. The model reproduced the spontaneous coiling occurring in the pile and attributed it to the dissipative locking of segments in mid-air creating a three-dimensional spiral structure.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2021)
Article
Physics, Fluids & Plasmas
Naoto Yokoyama, Hiroshi Yamashita, Kento Higashi, Yuta Miki, Tomoaki Itano, Masako Sugihara-Seki
Summary: Experimental and numerical studies on particle focusing in a square-tube flow revealed that the focusing patterns depend on polymer concentration, with transitions among patterns being driven by elastic forces due to the first normal stress difference and polymer elongation.
PHYSICAL REVIEW FLUIDS
(2021)
Article
Mathematics
T. Akinaga, T. M. Harvey-Ball, T. Itano, S. C. Generalis, E. C. Aifantis
Summary: In this study, a homotopy method is employed to address degeneracy caused by resonance in fluid motion, with the introduction of a symmetry breaking perturbation altering the resonant bifurcation tree and revealing previously unknown resonant higher order nonlinear solutions. The potential extension of this methodology to consider non-Newtonian gradient enhanced incompressible viscous fluids is also briefly discussed.
LOBACHEVSKII JOURNAL OF MATHEMATICS
(2021)
Article
Physics, Fluids & Plasmas
Fumitoshi Goto, Tomoaki Itano, Masako Sugihara-Seki, Takahiro Adachi
Summary: This study numerically investigates the bifurcation aspect of the wide-gap spherical Couette flow, focusing on the competition among polygonal coherence with different wave numbers observed over transitional Reynolds numbers. The results show the instability of the axisymmetric state and the bifurcation of threefold and fourfold spiral states at different transitional Reynolds numbers, shedding light on the stability of equilibrium states.
PHYSICAL REVIEW FLUIDS
(2021)
Article
Mechanics
Tomoaki Itano, Fumitoshi Goto, Kazuki Yoshikawa, Masako Sugihara-Seki
Summary: This study investigates the homotopy of a rotating threefold spiral state in a hybrid system with thermal stratification effects. The results show that the rotating wave state in a purely thermal convective system differs from the purely spherical Couette flow.
Article
Physics, Multidisciplinary
Tomoaki Itano, Keito Konno, Taishi Inagaki, Masako Sugihara-Seki
JOURNAL OF PHYSICS COMMUNICATIONS
(2019)
Article
Mechanics
Yusuke Morita, Tomoaki Itano, Masako Sugihara-Seki
JOURNAL OF FLUID MECHANICS
(2017)
