Aquacultural Engineering最新文献

Single pass saltwater disinfection using low voltage electrolysis: Potential implications for aquaculture systems 使用低压电解法对海水进行一次性消毒：对水产养殖系统的潜在影响

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-11-22 DOI: 10.1016/j.aquaeng.2024.102493

Jeffrey William Yuen , Hei Yuet Sabrina Lam , Avalon Berry , Dawson Chalmers , Ji Yang , Ju Zhang , Jason Chun-Ho Lam , Celia Schunter , Sophie St-Hilaire

Open net pen saltwater aquaculture faces criticism due to the potential transmission of pathogens between fish farms and to wild stocks. To address this issue and improve the sustainability and growth of net pen farming, closed containment farms have been suggested, but the cost and feasibility of disinfecting large volumes of water in these types of farms is problematic. We explored the potential for using electrolysis to disinfect saltwater in a flow-through system with water flow velocities between 47 and 105 cm/s. This was the first step to investigating whether this technology could be applied to saltwater flow-through closed containment systems. Various voltage levels (3.3–9.0 V) were applied to generate chlorine from saltwater. We found the disinfection properties of the system varied with wattage (i.e., voltage × ampere), velocity of water flow over the electrodes, salinity of water, and residual chlorine contact time. Wattage was highly correlated with the production of chlorine, and this relationship was dependent on water flow (p = 0.0398). A slower flow velocity led to higher chlorine concentration, and the effect was more pronounced at higher wattages. Using a zero-inflated negative binomial regression model, we found the probability of full disinfection was increased by increasing wattage (p < 0.001) and the residual chlorine contact time (p < 0.001). The level of disinfection (count model) suggested the number of bacteria in the treated samples was determined by the interaction between wattage and flow (p = 0.0056) and the interaction between wattage and salinity (p < 0.001). The bacterial count was also associated with residual chlorine contact time (p < 0.001). The results of this study, although preliminary and limited in their scale, offering a potential solution for disinfecting large volumes of seawater, which could make closed containment fish farming in the ocean viable for reducing bacterial transmission within a farm and to wild fish stocks.

开放式网箱海水养殖由于可能在养殖场之间以及向野生鱼类传播病原体而受到批评。为了解决这一问题，提高网箱养殖的可持续性和增长，有人建议采用封闭式养殖场，但在这类养殖场中对大量水进行消毒的成本和可行性是个问题。我们探索了在水流速度介于 47 厘米/秒和 105 厘米/秒之间的直流系统中使用电解法对盐水进行消毒的可能性。这是研究该技术能否应用于盐水流动封闭系统的第一步。我们采用了不同的电压水平（3.3-9.0 V）来从盐水中产生氯。我们发现，该系统的消毒性能随功率（即电压×安培）、电极上的水流速度、水的盐度和余氯接触时间而变化。瓦特数与氯的产生量高度相关，这种关系取决于水流（p = 0.0398）。流速越慢，氯浓度越高，瓦数越高，效果越明显。使用零膨胀负二项回归模型，我们发现完全消毒的概率随着功率的增加而增加（p < 0.001），余氯接触时间的增加也会增加（p < 0.001）。消毒水平（计数模型）表明，经处理样品中的细菌数量取决于瓦特数与流量之间的相互作用（p = 0.0056）以及瓦特数与盐度之间的相互作用（p < 0.001）。细菌数量还与余氯接触时间有关（p < 0.001）。这项研究的结果虽然是初步的，规模也有限，但为大量海水的消毒提供了一个潜在的解决方案，可使海洋中的封闭式养鱼业减少养殖场内和野生鱼类种群中的细菌传播。

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引用次数: 0

Novel and sustainable valorization of biogenic waste into microbial protein based fish dietary ingredient in bioreactor: Process optimization and sustainable utilization 在生物反应器中将生物废弃物转化为基于微生物蛋白的鱼类膳食配料的新颖和可持续的价值评估：工艺优化和可持续利用

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-11-17 DOI: 10.1016/j.aquaeng.2024.102483

Thejaswini , M.H. Chandrakant , A.M. Babitha Rani

Waste valorization is the concept of sustainability, and microbial floc is the valorised product of sustainable aquaculture. It converts nitrogenous waste into nutritious microbial protein that can replace fish meal partially or completely as feed for aquatic animals. The current study focuses on optimizing the process of production of microbial protein using aquaculture waste in a bioreactor and its utilization as feed for genetically improved farmed tilapia (GIFT) reared in inland saline groundwater with various inclusion levels. The retention time, aeration, and microbial flocculant (chitosan) were optimized to intensify the reaction, using a response surface methodology approach based on a full factorial experimental design. The chosen responses for evaluation were crude protein (CP), crude lipid (CL), and floc volume (FV). The interaction between aeration and retention time was found to play a significant role in the percentage of crude protein and crude lipid of microbial floc (p<0.001). The floc volume was significantly influenced by retention time and chitosan concentration (p<0.05). The process was optimized with 4 days of retention time, 30 ppm of chitosan concentration, and intermittent aeration (0.5 hr aeration and 0.5 hr no aeration), which resulted good quality microbial floc with a maximum CP of 24.74 %, a maximum CL of 2.13 %, and a FV of 13.75 ml. A completely randomized design with the inclusion of 0 %, 10 %, 20 %, and 30 % microbial floc (produced in a bioreactor) in feed was followed to evaluate the growth performance of GIFT. Among these, microbial flocs with a 20 % inclusion level showed a good growth trajectory. This study has shown that 20 % microbial floc meal in the diet is optimum for the growth of GIFT in inland saline groundwater. This study sustainably supports the waste valorization concept with microbial protein production in a bioreactor that is a suitable feed for GIFT.

废物价值化是可持续发展的概念，而微生物絮团则是可持续水产养殖的价值化产品。它将含氮废物转化为营养丰富的微生物蛋白，可部分或完全替代鱼粉作为水产动物的饲料。本研究的重点是优化生物反应器中利用水产养殖废弃物生产微生物蛋白的过程，并将其用作在内陆含盐地下水中饲养的基因改良养殖罗非鱼（GIFT）的饲料。采用基于全因子实验设计的响应面方法，对停留时间、曝气和微生物絮凝剂（壳聚糖）进行了优化，以强化反应。选定的评估反应为粗蛋白（CP）、粗脂肪（CL）和絮凝体体积（FV）。结果发现，通气量和停留时间之间的交互作用对微生物絮体的粗蛋白和粗脂百分比有显著影响（p<0.001）。絮团体积受停留时间和壳聚糖浓度的影响很大（p<0.05）。在保留时间为 4 天、壳聚糖浓度为 30 ppm 和间歇通气（通气 0.5 小时，不通气 0.5 小时）的条件下对工艺进行了优化，得到了高质量的微生物絮团，其最大 CP 值为 24.74%，最大 CL 值为 2.13%，FV 值为 13.75 ml。采用完全随机设计，在饲料中添加 0 %、10 %、20 % 和 30 % 的微生物絮团（在生物反应器中生产），以评估 GIFT 的生长性能。其中，添加量为 20% 的微生物絮凝物显示出良好的生长轨迹。这项研究表明，日粮中 20% 的微生物絮团粉最适合 GIFT 在内陆盐碱地下水中的生长。这项研究通过在生物反应器中生产微生物蛋白质，为废物价值化概念提供了可持续的支持，而微生物蛋白质是 GIFT 的合适饲料。

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引用次数: 0

Optimizing alkalinity control in recirculating aquaculture systems (RAS): A dynamic modelling approach 优化循环水养殖系统（RAS）的碱度控制：动态建模方法

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-11-15 DOI: 10.1016/j.aquaeng.2024.102492

Marie Aline Montjouridès , Susanna Röblitz , Håkon Dahle

Maintaining good water quality is essential for successful fish production in land-based recirculating aquaculture systems (RAS). Numerous interdependent factors influence water quality parameters, making it difficult to evaluate which operational strategies are most favorable. Mathematical models and model simulations have proven to be powerful tools to evaluate how RAS design and operation are linked to RAS dynamics, but these models rarely implement pH and carbonate species as dynamic variables. Here, we present a dynamic model for RAS (dynRAS) that combines rates of TAN (total ammonia nitrogen) removal, fish growth, and CO₂ and TAN excretion, with a reaction model for pH and the carbonate system formulated based on the law of mass action. A novel aspect of our approach is the incorporation of a dosage system modelled by a Hill-function, enabling the exploration of diverse dosing strategies for pH and alkalinity management. The model was validated based on empirical data from a pilot scale RAS system operated with a feeding regime involving 12 h of feeding per day. We found that model simulations could be used to accurately predict diurnal cycling patterns in RAS water quality parameters. Furthermore, we made use of simulations to assess how diurnal cycling varies with changing pH and alkalinity levels. Model results emphasize the complexity of pH and alkalinity control in RAS in relation to overall water quality management. Based on our simulations, we argue that what should be considered as optimal pH and alkalinity in RAS depends on the state of the system. Accordingly, optimal pH and alkalinity thresholds may vary between different RAS units and between different time points of a rearing cycle. More generally, we demonstrate how modelling and model simulations can be an effective way of getting insights into the dynamics of complex RAS interactions and provide a valuable tool to efficiently explore effects of different operational strategies on water quality parameters.

保持良好的水质是陆基循环水养殖系统（RAS）成功生产鱼类的关键。影响水质参数的相互依存因素众多，因此很难评估哪种操作策略最有利。数学模型和模型模拟已被证明是评估 RAS 设计和运行如何与 RAS 动态相关联的有力工具，但这些模型很少将 pH 值和碳酸盐种类作为动态变量。在此，我们提出了一种 RAS 动态模型（dynRAS），该模型结合了 TAN（总氨氮）去除率、鱼类生长率、二氧化碳和 TAN 排泄率，以及基于质量作用定律的 pH 值和碳酸盐系统反应模型。我们的方法的一个新颖之处是纳入了一个以希尔函数为模型的投药系统，从而能够探索出不同的 pH 值和碱度管理投药策略。该模型是根据一个中试规模的 RAS 系统的经验数据验证的，该系统采用每天投料 12 小时的投料制度。我们发现，模型模拟可用于准确预测 RAS 水质参数的昼夜循环模式。此外，我们还利用模拟来评估昼夜循环如何随 pH 值和碱度的变化而变化。模型结果强调了 RAS 中 pH 值和碱度控制与整体水质管理的复杂性。根据模拟结果，我们认为，RAS 中的最佳 pH 值和碱度取决于系统的状态。因此，最佳 pH 值和碱度阈值在不同的 RAS 单元和饲养周期的不同时间点之间可能会有所不同。总体而言，我们展示了建模和模型模拟如何成为深入了解复杂 RAS 相互作用动态的有效方法，并为有效探索不同操作策略对水质参数的影响提供了宝贵的工具。

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引用次数: 0

Hydrodynamic responses of a large flexible net swinging in waves 大型柔性网在波浪中摆动的水动力响应

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-11-07 DOI: 10.1016/j.aquaeng.2024.102491

Wude Xie , Zhaoyang Jiang , Lu Wang , Zhenlin Liang

In deep-sea aquaculture cages, large flexible nets are usually mounted on the steel frames of aquaculture cages, which are easily broken. When a cage vibrates over time, the flexible nets also oscillate, causing relative motions with respect to fluid flows. This study focuses on the hydrodynamic behaviors of a large flexible net swinging in waves, in which three different types of swings are simulated with the swing center located above, on, and below the net, respectively. The incoming waves are simulated using the Airy wave theory. The nonlinear vibrations of the flexible net in three dimensions are solved using the lumped-mass method. The influences of swing amplitudes and frequencies on the vibrations of the net are analyzed in detail. It can be known that with the increase of swing amplitude, the vibration displacements of the net in the horizontal direction decrease, while they increase in the vertical direction. Furthermore, the dynamic tensions of net twines increase as the swing angular frequency rises.

在深海水产养殖网箱中，大型柔性网通常安装在水产养殖网箱的钢架上，而钢架很容易破损。当网箱随时间振动时，柔性网也会随之振动，从而引起相对于流体流动的相对运动。本研究的重点是大型柔性网在波浪中摆动的流体动力学行为，其中模拟了三种不同类型的摆动，摆动中心分别位于网的上方、上方和下方。入射波使用艾里波理论进行模拟。柔性网在三维空间的非线性振动采用块状质量法求解。详细分析了摆幅和频率对柔性网振动的影响。可以看出，随着摆动幅度的增大，柔性网在水平方向上的振动位移减小，而在垂直方向上的振动位移增大。此外，随着摆动角频率的增加，网的动态张力也会增加。

引用次数: 0

Unsteady flow dynamic response in the cylinder-netting structure for the design of offshore fish farm systems using an SST-IDDES turbulence model 利用 SST-IDDES 湍流模型设计近海养鱼场系统的圆筒网状结构中的非稳定流动态响应

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-11-01 DOI: 10.1016/j.aquaeng.2024.102480

Bruno Thierry Nyatchouba Nsangue , Hao Tang

An improved comprehension of the flow dynamics and hydrodynamic features of the interaction between the cylinder and nettings, crucial elements of offshore aquaculture systems, can optimize the development of environmentally friendly and sustainable large-scale aquaculture pens. This study investigates the instantaneous flow fields and hydrodynamic response in the interaction between the cylinder and netting structures using a high-fidelity Computational Fluid Dynamics approach based on the k-ω shear stress transport-improved delayed detached eddy simulation turbulence model within the Large Eddy Simulation region. The Richardson Extrapolation method was employed to assess the convergence of the numerical solutions across various levels of mesh refinement. The conducted research revealed that the inclusion of the cylinder resulted in an increase in the drag coefficient ranging from 2.25 % to 36.78 % due to the complex interaction between the combined netting-cylinder, shear layer instabilities, and vortex shedding, when compared to the two individual nettings. As Reynolds number and cylinder diameter increased, cylinder drag coefficients decreased, causing large-scale vortex shedding and unsteady turbulent wake flow. Furthermore, the wake interactions of the netting are relatively strong with low flow velocity when the solidity ratio and twine diameter increased due to the disruption caused by the netting-twine, mesh shape, and netting position in the flow passage. The drag and lift coefficients of the combined cylinder-netting structure increased with increasing solidity ratio, inclination angle, and decreasing flow velocity. The Fourier analysis showed that the hydrodynamic coefficients of only the cylinder and single netting are primarily low-Strouhal numbers activities, while the hydrodynamic forces of the combined cylinder-netting structure are primarily low-frequency activities connected to unsteady turbulent flow streets. The understanding of the hydrodynamic and flow instabilities that occur close to the wake of the contact between the cylinder and the nettings is of utmost significance for the purpose of optimizing the design of offshore aquacultural structures, particularly for situations that are characterized by biofouling.

圆筒和网箱是近海水产养殖系统的关键要素，更好地理解圆筒和网箱之间相互作用的流动动力学和水动力特征，可以优化环境友好型和可持续的大规模水产养殖围栏的发展。本研究采用高保真计算流体动力学方法，基于大涡模拟区域内经 k-ω 剪切应力传输改进的延迟分离涡模拟湍流模型，研究了圆筒和网箱结构之间相互作用的瞬时流场和水动力响应。采用理查德森外推法评估了不同网格细化程度下数值解的收敛性。研究结果表明，与两个单独的网状物相比，由于网状物与圆柱体、剪切层不稳定性和涡流脱落之间的复杂相互作用，圆柱体的加入导致阻力系数增加了 2.25% 至 36.78%。随着雷诺数和气缸直径的增大，气缸阻力系数降低，导致大规模涡流脱落和不稳定湍流尾流。此外，当固结比和麻绳直径增大时，由于网绳、网孔形状和网绳在流道中的位置造成的干扰，网绳在低流速时的尾流相互作用相对较强。组合圆筒-网状结构的阻力系数和升力系数随着固度比、倾角的增大和流速的减小而增大。傅立叶分析表明，只有圆筒和单一网布的水动力系数主要是低斯特劳哈尔数活动，而圆筒-网布组合结构的水动力主要是与不稳定湍流街道有关的低频活动。了解圆筒和网衣接触尾流附近发生的水动力和流动不稳定性，对于优化近海水产养殖结构的设计，尤其是生物污损情况下的设计，具有极其重要的意义。

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引用次数: 0

A probabilistic framework for offshore aquaculture suitability assessment using bivariate copulas 利用双变量协方差进行近海水产养殖适宜性评估的概率框架

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-11-01 DOI: 10.1016/j.aquaeng.2024.102479

R. Santjer , P. Mares-Nasarre , L. Vilmin , G.Y.H. El Serafy , O. Morales-Nápoles

Aquaculture at sea is gaining increasing importance, not only as a (local) food source but also due to its potential of being combined with other offshore activities such as wind parks. Nevertheless, experience of offshore aquaculture is limited. This study aims to provide a framework to evaluate offshore aquaculture suitability accounting for the probabilistic dependence between relevant variables. This framework is applied to obtain suitability maps of aquaculture for the North Sea for the blue mussel Mytilus edulis and the sugar kelp Saccharina latissima. For each of these species, three ecological variables are selected and the optimal growth and critical survival limits are defined. Here, suitability is defined as the probability of meeting these conditions. Data on the selected variables is extracted from a large-scale 3D hydrodynamic and ecological model of the northwest European Shelf, of which daily extremes are sampled. The probabilistic model is developed using bivariate copula models, which are fitted to each variable pair to describe their joint distribution function at each studied location. Empirical distribution functions are used to describe the univariate distribution function of each variable and location. Using Monte-Carlo simulations, the probability of meeting the optimal and critical limits is estimated and suitability maps accounting for the probabilistic dependence between the variables are generated. In addition, suitability maps disregarding the dependence are generated and compared to those accounting for the probabilistic dependence. It was found that considering the dependence between variables significantly improves the accuracy of the results for optimal and critical growth conditions for both species. The presented method allows to identify potential areas where blue mussel and sugar kelp cultivation is the most suitable. For instance, in this study, a north-south elongated area west of the German and Danish coast appears to be most suitable for blue mussels, while estuaries and rivers are found the most suitable for the sugar kelp.

海上水产养殖的重要性与日俱增，它不仅是一种（当地）食物来源，还因为它有可能与风力发电厂等其他海上活动相结合。然而，近海水产养殖的经验有限。本研究旨在提供一个评估近海水产养殖适宜性的框架，其中考虑了相关变量之间的概率依赖关系。应用该框架可获得北海蓝贻贝（Mytilus edulis）和糖海带（Saccharina latissima）的水产养殖适宜性图。为每个物种选择了三个生态变量，并定义了最佳生长和临界存活极限。这里，适宜性被定义为满足这些条件的概率。所选变量的数据来自西北欧大陆架的大型三维水动力和生态模型，并对其中的日极端值进行了取样。概率模型是利用双变量协整模型开发的，每个变量对都拟合了协整模型，以描述它们在每个研究地点的联合分布函数。经验分布函数用于描述每个变量和地点的单变量分布函数。通过蒙特卡洛模拟，估算出达到最佳和临界极限的概率，并生成反映变量之间概率依赖关系的适宜性图。此外，还生成了不考虑依赖性的适宜性图，并与考虑概率依赖性的适宜性图进行比较。研究发现，考虑变量之间的依赖性可显著提高两种物种最佳和临界生长条件结果的准确性。所提出的方法可以确定最适合养殖蓝贻贝和糖海带的潜在区域。例如，在这项研究中，德国和丹麦海岸以西的南北拉长区域似乎最适合养殖蓝贻贝，而河口和河流则最适合养殖糖海带。

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引用次数: 0

Aquaculture fish counting and mass estimation method via vibration signal processing 通过振动信号处理进行水产养殖鱼类计数和质量估算的方法

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-10-26 DOI: 10.1016/j.aquaeng.2024.102478

Liwen Qian , Guoyan Yu , Haochun Liu , Junxi He , Zijian He

Information on the mass and counts of fish at different growth stages is crucial for precision feeding management and the improvement of fish farming environments. Grading operation plays a significant role in management and harvesting of cage culture. In this study, a counting and mass estimation of fish via vibration signal process method was proposed, using a roller-type fish grader to count and estimate the mass of fish during the grading process. First, we replicate fish dropping events during the grading process, when fish impact the mass measurement plate, on a test bench, and waveform data from vibration sensors located on the mass measurement plate were collected. Secondly, the waveform signal was analyzed, and trigger thresholds were set. When the signal exceeded the threshold, performed mathematical operations on the signal's data for counting and mass estimation until the signal left the threshold. The method was conducted on a test bench, and the results showed a coefficient of determination (R²) of 0.9970 and a Root Mean Square Error (RMSE) of 4.1724 g for mass estimation. Furthermore, the method was validated on a roller-type fish grader in practical applications, achieving average R² of 0.9862 and RMSE of 8.8529 g. The accuracy of fish counting reached 100 %. These experimental results demonstrate the proposed method can accurately count and estimate mass of fish.

不同生长阶段鱼类的质量和数量信息对于精确饲养管理和改善养鱼环境至关重要。分级操作在网箱养殖的管理和收获中发挥着重要作用。本研究提出了一种通过振动信号处理进行鱼类计数和质量估算的方法，利用滚筒式鱼类分级机对分级过程中的鱼类进行计数和质量估算。首先，我们在试验台上复制了分级过程中鱼撞击质量测量板时的掉落事件，并收集了来自质量测量板上振动传感器的波形数据。其次，对波形信号进行分析，并设置触发阈值。当信号超过阈值时，对信号数据进行数学运算，以进行计数和质量估算，直到信号离开阈值。该方法在试验台上进行了测试，结果显示，质量估计的决定系数（R²）为 0.9970，均方根误差（RMSE）为 4.1724 克。此外，该方法还在滚筒式鱼类分级机上进行了实际应用验证，平均 R² 为 0.9862，RMSE 为 8.8529 克。鱼体计数的准确率达到了 100%。这些实验结果表明，所提出的方法能准确计数和估算鱼的质量。

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引用次数: 0

Experimental study on hydrodynamic performance of the semi-submersible vessel-shaped fish cage 半潜式船形鱼笼的流体力学性能实验研究

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-10-24 DOI: 10.1016/j.aquaeng.2024.102482

Guoqiang Li , Xiaobin Li , Yonghe Xie , Chunhui Zhao , Peng Xu

Deep-sea net cages play a vital role in expanding offshore farming in modern marine fisheries. In this paper, a model-scale 1:40 tank experiment was conducted for a vessel-shaped truss-structured single-point mooring deep-sea aquaculture net cage. The study focused on the hydrodynamic characteristics, including the effect of current, wave, and net on the mooring force, heave, and pitch motion behaviors. Experimental results indicate that the mooring force increases with the current velocity, draught of the cage, and wave height, but decreases with the wave period increase. Both heave and pitch movements amplitudes increase with wave height. While heave motion amplitude initially declines and then ascends with wave periods, pitch motion shows the opposite pattern. Besides the net has an obvious damping effect on the pitch motion. These results can provide data support for the design and offshore installation of vessel-shaped truss-structured net cages in the future.

深海网箱在现代海洋渔业扩大离岸养殖方面发挥着重要作用。本文对船形桁架结构单点系泊深海养殖网箱进行了 1:40 模型比例水槽实验。研究的重点是水动力特性，包括水流、波浪和网对系泊力、起伏和俯仰运动行为的影响。实验结果表明，系泊力随流速、网箱吃水和波高的增加而增加，但随波浪周期的增加而减小。起伏和俯仰运动的振幅都随着波高的增加而增大。起伏运动振幅随波浪周期的变化先减小后增大，而俯仰运动振幅则与之相反。此外，网对俯仰运动有明显的阻尼作用。这些结果可为今后船形桁架结构网箱的设计和海上安装提供数据支持。

引用次数: 0

A robotic fish processing line enhanced by machine learning 通过机器学习增强的机器人鱼类加工生产线

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-10-24 DOI: 10.1016/j.aquaeng.2024.102481

Sangam Mainali, Cheryl Li

This paper presents the design of a comprehensive automatic fish processing line utilizing machine learning algorithms. The processing line encompasses several essential steps, including fish identification by type, fish sorting by size, fish orientation based on shape, and fish cutting at the optimal chopping points. The primary objective of this design is not just automation but also maximizing economic benefits by preserving the maximum amount of fish meat during the cutting process, achieved through the application of machine learning algorithms. To accomplish these goals, we employ a combination of transfer learning and convolutional neural networks to establish criteria for actions across all stages of automatic fish processing. At the heart of the processing station is a conveyor belt equipped with numerous sensors and lenses. Positioned along this conveyor belt are two robotic arms, responsible for precise positioning and cutting operations, all guided by the machine learning algorithms. To provide a visual representation of these design concepts, we have created a 3D SolidWorks model.

本文介绍了利用机器学习算法设计的鱼类综合自动加工生产线。该加工线包含几个基本步骤，包括按类型识别鱼、按大小分拣鱼、根据形状确定鱼的方向，以及在最佳切割点切割鱼。该设计的主要目标不仅是实现自动化，而且还要通过应用机器学习算法，在切割过程中最大限度地保留鱼肉，从而实现经济效益最大化。为了实现这些目标，我们采用了迁移学习和卷积神经网络相结合的方法，为鱼类自动加工的各个阶段制定行动标准。加工站的核心是一条传送带，上面装有许多传感器和镜头。传送带上有两个机械臂，负责精确定位和切割操作，所有操作都由机器学习算法指导。为了直观地展示这些设计理念，我们创建了一个 3D SolidWorks 模型。

引用次数: 0

Temporal dynamics of protist communities and environmental factors in the horizontal flow-polyculture pond aquaculture model of Sinonovacula constricta 缢蛏水平流聚养池塘养殖模式中原生生物群落与环境因素的时间动态变化

IF 3.6 2区农林科学 Q2 AGRICULTURAL ENGINEERING

Aquacultural Engineering

Pub Date : 2024-10-21 DOI: 10.1016/j.aquaeng.2024.102477

Minhai Liu , Zhongneng Yan , Chengwei Huang , Zhihua Lin , Zhilan Peng , Chenxi Zhao , Xiafei Zheng

The horizontal flow (HF)–polyculture pond (PP) model has emerged as a new aquaculture model that has attracted considerable attention. The growth of Sinonovacula constricta in the HF is highly dependent on phytoplankton in the PP; however, the current understanding of the basic microbes in the HF-PP model research remains insufficient. To address this knowledge gap, we analyzed the temporal dynamics of protist communities in water and sediment samples obtained from the HF and PP in this study. In addition, we measured the temporal variations in physicochemical factors in these water and sediment samples. A comparison of water quality data between HF and PP revealed that HF effectively reduced the total nitrogen (TN) and total phosphorus (TP) levels in the polyculture ponds. Furthermore, Diatomea and Ciliophora were the predominant phyla in all samples. In the horizontal-flow water samples, significant alterations were observed over time in Skeletonema, Strombidium, and Gyrodinium genera. The dynamic pattern of the genus in the polyculture pond water (PPW) was similar to that in the horizontal flow water (HFW). Furthermore, Skeletonema abundance decreased over time in the horizontal flow sediment (HFS). Skeletonema and Cyclotella were dominant in polyculture pond sediment (PPS). There was a certain degree of community succession throughout the experiment in the HFW and PPW, but not in the HFS or PPS. Correlation analysis revealed that water temperature (WT), salinity(SAL)，dissolved oxygen (DO), pH, phosphate, and silicate played key roles in driving variations in the protist community. These findings contribute to our understanding of complex protist community dynamics within the HF-PP aquaculture model, shedding light on the roles of various environmental factors in shaping protist communities and water quality.

水平流（HF）-聚养池（PP）模式作为一种新型水产养殖模式备受关注。缢蛏在 HF 中的生长高度依赖于 PP 中的浮游植物；然而，目前对 HF-PP 模型研究中基本微生物的了解仍然不足。为了填补这一知识空白，我们在本研究中分析了从高频和低频获得的水样和沉积物样本中原生生物群落的时间动态。此外，我们还测量了这些水样和沉积物样本中理化因子的时间变化。通过比较 HF 和 PP 的水质数据发现，HF 有效降低了多养殖池塘中的总氮（TN）和总磷（TP）含量。此外，硅藻和纤毛虫是所有样本中的主要门类。在水平流动的水样中，观察到 Skeletonema、Strombidium 和 Gyrodinium 属随着时间的推移发生了显著变化。多养殖池塘水（PPW）中该属的动态模式与水平流水（HFW）中的类似。此外，水平流沉积物（HFS）中的 Skeletonema 丰度随着时间的推移而降低。在多养殖池塘沉积物（PPS）中，骷髅头菌和旋毛虫占优势。在整个实验过程中，水平流沉积物（HFW）和聚丙烯流沉积物（PPW）中的群落有一定程度的演替，但在水平流沉积物（HFS）和聚丙烯流沉积物（PPS）中则没有。相关分析表明，水温（WT）、盐度（SAL）、溶解氧（DO）、pH 值、磷酸盐和硅酸盐在驱动原生生物群落变化方面起着关键作用。这些研究结果有助于我们理解高频-低频水产养殖模式中复杂的原生生物群落动力学，揭示了各种环境因素在形成原生生物群落和水质中的作用。

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