Development Of Marine Resources Research Articles

Research on modulation recognition of underwater acoustic communication signal based on deep learning

Marine information technology plays a important role in the development of marine resources development, marine climate early warning, and other industries. Underwater acoustic communication technology can help us better access marine information. The performance of the underwater acoustic signal modulation recognition algorithm depends on the accuracy of feature extraction. however, due to excessive underwater noise, many traditional algorithms can not recognize features well. For this reason, this paper proposes a modulation recognition network for aquatic communication signals based on deep learning. ResNet can capture the characteristics of deep features and combines ResNet with a modulation recognition network. Finally, the experiment proves the effectiveness of this method.

Antimicrobial peptides from marine animals: Sources, structures, mechanisms and the potential for drug development

The emergence of antibiotic-resistant bacteria has become a major challenge in current clinical treatment. As essential natural molecules involved in innate immunity, antimicrobial peptides (AMPs) have the potential to break the limits of antibiotic resistance. While AMPs are widely presented in various organisms on this planet, the marine environment is unique in generating a large number of AMPs that exhibit characteristic structures and functions. This review summarizes the structures and mechanisms of action of AMPs derived from invertebrates, fish, amphibians, reptiles, and mammals in the ocean. The comparison of AMPs from organisms in different habitats demonstrates the preference of Arg (arginine) and Leu (leucine) in marine AMPs, which might be associated with the adaptation to the unique features of bacterial membranes in marine environments. In addition, the potential and applications of marine AMPs for the development of novel antibiotics are also described. These summaries are expected to provide a reference for the development and utilization of marine resources in drug development or aquiculture.

Study on the Evaluation of the Carrying Capacity of Marine Resources and Environment in Weihai City in China

This paper establishes a marine resources and environment carrying capacity evaluation index system from the socio-economic system, marine resources system and marine environment system for the development of marine economy of Weihai in China, adopts the entropy weight TOPSIS model to quantitatively analyze the marine resources and environment carrying capacity of Weihai from 2011 to 2020, and uses the changes in these ten years as an entry point to analyze the problems in the development of marine resources, environmental protection and sustainable economic development in Weihai in a targeted manner. The model is used as a starting point to analyse the problems in the development of marine resources, environmental protection and sustainable economic development in Weihai, and to propose timely countermeasures and suggestions in the areas of laws and regulations, development and construction, and industrial transformation.

Development of ROV Simulator based on Real Oceanographic Data

In recent years, demand for efficient oceanographic research for the development of marine resources has been increasing on a global scale. In general, research and operation training on underwater robotics in the ocean is very costly, and the climate and conditions of the ocean may make it impossible to conduct experiments. In this paper, we introduce an ocean simulator using real oceanographic data that can avoid these issues. First, we treat Choreonoid which is an integrated software for robots applied by National Institute of Advanced Industrial Science and Technology (AIST), as the basis of the simulator software. Furthermore, to demonstrate its feasibility in a more realistic ocean environment, we introduce the seabed data obtained from oceanographic research and a function to reproduce ocean currents on the simulator. In this paper, self-localization experiment is conducted to demonstrate the effectiveness of the simulator for oceanographic research.

Study on a Circular Cylindrical Floating Device and Its Motion Response Characteristics

In this paper, a circular cylindrical floating device design is proposed by combining the structural features of the cylindrical Floating Production Storage and Offloading (FPSO) and the deep-sea Spar platform. It is suitable for deep-water oil and gas field development environment in the South China Sea. This floating device adds six floats with a Spar platform hard tank role based on the cylindrical FPSO to improve the buoyant center. This paper analyzes the motion response characteristics of the circular cylindrical floating device in waves by the Eulerian multi-phase flow model of STAR-CCM+. The results show that the pitch motion characteristics of the circular cylindrical floating device are better than those of the cylindrical FPSO and ship-type FPSO in the reference [8]. In addition, the paper also investigates the motion response of the circular cylindrical floating device with different directions of the incoming flow. The analysis shows that this floating device has the lowest motion response at 30° direction incoming flow. And the Response Amplitude Operator (RAO) of pitch motion shows a negative correlation with the incoming flow direction. The research results of this paper can provide a reference for the future development of marine resources, and have a certain practical significance.

Identifying Submarine Engineering Geologic Hazards in a Potential Gas Hydrate Target Area on the Southern Continental Margin of the South China Sea

The southern continental margin-slope area of the South China Sea is a complex passive continental margin with diverse tectonic structures and movements. This area is rich in gas hydrate resources and is also an area with a high incidence of potential geological hazards. Identifying and understanding the potential submarine geological hazards in this area is very important for disaster prevention and management during the future exploration and development of marine resources. In this paper, five types of potentially hazardous geological bodies are identified in the research area through high-precision two-dimensional seismic processing and interpretation, including submarine mounds, pockmarks, mass transport deposits, submarine collapses and faults. At the same time, the seismic reflection characteristics and the changes in its morphology and surrounding strata are described. In addition to the causes of geological hazards in this region and their influence on exploration and development, the research prospects of geological hazards in this region are also suggested. Special tectonic and sedimentary conditions, fluid activities and hydrate decomposition may be the conditions for geological hazards in this region, which pose a significant threat to the exploration and development of seabed resources and marine engineering construction in this region. Not only does our conclusion provide useful data for the development and utilization of gas hydrate, but it also presents theoretical suggestions for reducing geological hazards in the development process.

Flow Electrode Capacitive Deionization System with Simultaneous Desalting of Na+ and Gathering of Na+

Oceans contain many freshwater resources and metal elements that people need, so the rational development of marine resources can solve the two major problems of shortage of freshwater resources and metal elements for people. To solve these two challenges, a system was designed to obtain freshwater resources and metallic elements simultaneously. An ion enrichment module was added to the conventional flow capacitor deionization system to collect metal elements while the seawater was deionized. A flowing electrode allows the metal elements to enter the flowing electrode through the desalination ability. It transports the metal elements to the enrichment module through the fluidity of the fluid while reducing the ion concentration at the flowing electrode, thus reducing the effect caused by the rejection of the same ion and collecting and enriching the metal elements. We purchased activated carbon to test the feasibility of the system with different mass fractions of activated carbon suspensions. The results showed that the elemental enrichment capacity of the system increased from 12.291 to 14.795 mg, and the enrichment rate increased from 13.536 to 16.294 mg cm-2 h-1 as the mass fraction of activated carbon increased. Thus, the system accomplished the goals of desalination and metal collection simultaneously.

Deterministic ship roll forecasting model based on multi-objective data fusion and multi-layer error correction

With the increasing frequency of international shipping and marine resources development activities, ship motion prediction plays an increasingly important role in ensuring the safety of offshore operations. However, in the field of ship motion prediction, the deep feature information of raw high-resolution ship motion data, as well as the predictable components in the initial prediction residuals is usually neglected. In this paper, a deterministic ship roll forecasting model based on multi-objective data fusion and multi-layer error correction is proposed. The proposed model consists of three stages, which are data pre-processing stage, multi-objective data fusion forecasting stage, and multi-layer error correction stage. To verify the stability and validity of the proposed model, an experimental study was conducted using three sets of measured ship roll motion data collected in the South China Sea from 2018 to 2020. Taking the 1-step, 5-step, and 10-step predictions of dataset #1 as an example, the RMSE values of the proposed model are 0.0130°, 0.0612°, and 0.0791°, respectively. Through three analytical experiments and four comparison experiments, it is proved that the proposed model is able to obtain accurate deterministic point forecasts, which can better assist the sailor in decision making.

Applying life history traits to eco-labelling schemes for fisheries management: A case study in Taiwan

Eco-labelling scheme is an emerging management strategy for promoting the sustainable development of marine resources and fisheries. The recommendation lists for seafood that reflects the status of exploited fish stocks, based on scientific evidences and categorize species accordingly is a commonly used eco-labelling scheme. Nevertheless, the status of fish stocks may be influenced by abiotic factors and biotic factors which may affect the categorization of fish species in recommendation lists. In this study, four life history traits (maximum length, length at maturity, age at maturity and growth coefficient) and two ecological parameters (trophic level and unit price) of 35 marine fishes in the waters around Taiwan were examined through multivariate statistical analysis and compared against the Seafood Guide Taiwan. Two main factors were identified through principal component analysis. The first factor was correlated with maximum length, length at maturity and growth coefficient, and the second factor was correlated with age at maturity and trophic level. Two fish groups were identified according to the PCA bi-plot. The Best Choices and Good Alternatives categories had higher growth coefficients, and the Avoid group had a smaller age at maturity. The results indicated that the life history traits of fish stocks may serve as complementary information to seafood guides, and may have substantial implications for the future planning of eco-labelling schemes. Nevertheless, when developing a framework for a domestic eco-labelling scheme, the decision-makers should consider the applicability of framework components in the global market as well as research on fish stock status and management strategies.

Catalytic ozonation for imazapic degradation over kelp-derived biochar: Promotional role of N- and S-based active sites

It is a feasible strategy to prepare reliable biochar catalysts for heterogeneous catalytic ozonation (HCO) processes by using inexpensive, high quality, and easily available raw materials. Here, an environmentally friendly, simple, and green biochar catalyst rich in nitrogen (N) and sulfur (S) has been prepared by the pyrolysis of kelp. Compared with directly carbonized kelp biomass (KB), acid-activated KB (KBA) and base-activated KB (KBB) have higher specific surface areas and more extensive porous structures, although only KBB displays effective ozone activation. Imazapic (IMZC), a refractory organic herbicide, was chosen as the target pollutant, which has apparently not hitherto been investigated in the HCO process. Second-order rate constants (k) for the reactions of IMZC with three different reactive oxygen species (ROS), specifically kO3, IMZC, kOH, IMZC, and k1O2, IMZC, have been determined as 0.974, 2.48 × 109, and 6.23 × 105 M−1 s−1, respectively. The amounts of graphitic N and thiophene S derived from the intrinsic N and S showed good correlations with the IMZC degradation rate, implicating them as the main active sites. OH and O2− and 1O2 were identified as main ROS in heterogeneous catalytic ozonation system for IMZC degradation. This study exemplified the utilization of endogenous N and S in biological carbon, and provided more options for the application of advanced oxidation processes and the development of marine resources.

Physiological basis and differentially expressed genes in the salt tolerance mechanism of Thalassia hemprichii.

Seagrass plays a vital role in the stability of marine ecology. The human development of marine resources has greatly affected the survival of seagrass. Seawater salinity is one of the important factors affecting its survival. Seagrass can survive in high saline environments for a long time and has evolved a variety of effective tolerance mechanisms. However, little is known about the molecular mechanisms underlying salinity tolerance by seagrass. Thalassia hemprichii is a seagrass species with a global distribution. It is also an ecologically important plant species in coastal waters. Nevertheless, the continuous environmental deterioration has gradually reduced the ecological niche of seagrasses. In this study, experiments were conducted to examine the effects of salinity changes on T. hemprichii. The result showed that the optimal salinity for T. hemprichii is 25 to 35 PSU. Although it can survive under high and low salinity, high mortality rates are common in such environments. Further analyses revealed that high salinity induces growth and developmental retardation in T. hemprichii and further causes yellowing. The parenchyma cells in T. hemprichii also collapse, the structure changes, soluble sugar accumulates rapidly, soluble proteins accumulate rapidly, the malondialdehyde (MDA) content reduces, and lipid peroxidation reduces in plant membranes. The molecular mechanisms of salt tolerance differ significantly between marine and terrestrial plants. We found 319 differentially expressed genes (DEGs). These genes regulate transport and metabolism, promoting environmental adaptation. The expression of these genes changed rapidly upon exposure of T. hemprichii to salinity stress for three hours. This is the first report on the physiological and biochemical changes and gene expression regulation of T. hemprichii under different salinity conditions. The findings of this study well deepen our understanding of T. hemprichii adaptations to changes in the shoal living environment.

Research on a New Type of Polar Icebreaking Guide Ship based on MATLAB

Polar regions are rich in natural resources and have valuable scientific research value. In recent years, with the deepening of polar exploration and the development of marine resources in the frigid zone, the development of icebreakers, as an important marine equipment in polar rescue, channel opening, and material supply, has attracted more and more attention and attention from various countries. Aiming at the current common icebreakers and icebreaking methods, through theoretical research and simulation analysis, the author designs a polar icebreaking guide ship with a new icebreaking method. While adjusting the ice breaking device in real time according to the thickness of the ice layer, according to the forward and inverse solution algorithm for the motion planning of the robot arm, the precise control of the ice breaking robot arm is completed, and the purpose of energy saving and emission reduction is achieved at the same time. Provide more intelligent and energy-saving options for the construction and development of icebreaker equipment in my country.

Hydrodynamic Analysis of a Modular Integrated Floating Structure System Based on Dolphin-Fender Mooring

For both the expansion of important islands/reefs and the development of marine resources in South China Sea, a modular integrated floating structure (MIFS) system with tidal self-adaptation dolphin-fender mooring (DFM) has been proposed. The DFM, coupled with wave energy converters (WEC), can serve as an anti-motion system. Considering both the modules’ hydrodynamic interaction effect and the connectors’ mechanical coupling effect, both dynamic responses of the MIFS system and the WEC’s output power characteristics were investigated under typical sea conditions. Based on the comprehensive consideration of key factors (safety, economy, and comfort), the effects of both the DFM and module connectors were systematically studied for the MIFS system. Preliminarily optimal design parameters of corresponding connectors and WECs were suggested. The security of the MIFS system under extreme sea conditions was checked, and a promising survival strategy has been proposed. In addition, the modular expansion scheme of the MIFS system was further discussed, and the results indicated that the proposed MIFS system shows good expansibility. The WEC can not only improve both dynamic responses and the comfort of inner modules, but also make considerable wave energy contributions.

Modeling and performance analysis of electro-mechanical systems for ocean thermal-driven buoys

Marine resources exploration and development can’t be separated from the underwater exploration buoy, battery capacity limits the working time and range of the buoy, the use of ocean thermal energy for underwater exploration buoy energy supply can effectively solve the problem of energy supply. The solid-liquid phase change energy storage technology was used to capture ocean thermal energy, and the electro-mechanical system was used to convert ocean thermal energy into electrical energy to realize the self-supply of buoy energy. In this paper, we studied the influence of the system parameters on the system performance by analyzing the working process of the buoy electromechanical system, establishing the mathematical model of the whole system, and combining AMESim/Simulink simulation technology to reveal the law of ocean thermal energy generation. The results show that increasing the volume of the accumulator and reducing the displacement of the hydraulic motor can help to increase the power generation of the generator and choosing a suitable load can help to increase the power generation.

Research on Adaptive Sliding Mode Control of UVMS Based on Nonlinear Disturbance Observation

The underwater vehicle manipulator system is a powerful tool for the exploration and development of marine resources. Due to the complexity of the marine environment, there are many disturbance factors and difficult to control. Taking the fixed depth control in hovering mode as an example, the vertical plane decoupling control model is established, and the adaptive sliding mode control method based on the disturbance observation is studied. The nonlinear disturbance observation is used to estimate the external unknown disturbance in real time, and the adaptive sliding mode method is used for compensation control. Simulation results show that the control method can effectively compensate for the sudden disturbance term, does not produce obvious trim motion, has strong robustness, and provides a reliable and stable base for the operation of the underwater manipulators. Finally, the operation experiments in the pool and real sea area under the disturbance condition are carried out, respectively. The experimental results show that the control effect is good and the stability is greatly improved compared with the traditional control method.

Regulatory effects of marine polysaccharides on gut microbiota dysbiosis: A review.

The gut microbiota dysbiosis is a state which the physiological combinations of flora are transformed into pathological combinations caused by factors such as diets, pollution, and drugs. Increasing evidence shows that dysbiosis is closely related to many diseases. With the continuous development and utilization of marine resources, marine polysaccharides have been found to regulate dysbiosis in many studies. In this review, we introduce the types of dysbiosis and the degree of it caused by different factors. We highlight the regulating effects of marine polysaccharides on dysbiosis as a potential prebiotic. The mechanisms of marine polysaccharides to regulate dysbiosis including protection of intestinal barrier, regulatory effect on gut microbiota, alteration for related metabolites, and some other possible mechanisms were summarized. And we aim to provide some references for the high-value utilization of marine polysaccharides and new targets for the treatment of gut microbiota dysbiosis by this review.

Semantic segmentation method of underwater images based on encoder-decoder architecture.

With the exploration and development of marine resources, deep learning is more and more widely used in underwater image processing. However, the quality of the original underwater images is so low that traditional semantic segmentation methods obtain poor segmentation results, such as blurred target edges, insufficient segmentation accuracy, and poor regional boundary segmentation effects. To solve these problems, this paper proposes a semantic segmentation method for underwater images. Firstly, the image enhancement based on multi-spatial transformation is performed to improve the quality of the original images, which is not common in other advanced semantic segmentation methods. Then, the densely connected hybrid atrous convolution effectively expands the receptive field and slows down the speed of resolution reduction. Next, the cascaded atrous convolutional spatial pyramid pooling module integrates boundary features of different scales to enrich target details. Finally, the context information aggregation decoder fuses the features of the shallow network and the deep network to extract rich contextual information, which greatly reduces information loss. The proposed method was evaluated on RUIE, HabCam UID, and UIEBD. Compared with the state-of-the-art semantic segmentation algorithms, the proposed method has advantages in segmentation integrity, location accuracy, boundary clarity, and detail in subjective perception. On the objective data, the proposed method achieves the highest MIOU of 68.3 and OA of 79.4, and it has a low resource consumption. Besides, the ablation experiment also verifies the effectiveness of our method.

Construction and application of bionic antifouling coatings inspired by soft coral

AbstractMarine biofouling will bring a series of environmental and social problems, which restrict the development and utilisation of marine resources. Therefore, how to prevent biofouling has become a global issue. With the exploration of antifouling methods, bionic antifouling technology with environmentally friendly, broad‐spectrum, and long‐term advantages has gradually attracted people's attention. Inspired by the antifouling strategy of soft coral (Sarcophyton trocheliophorum), the silicone rubber (RTV‐2) with similar elasticity to coral skin was selected as the substrate. The composite structure of the upper transparent layer and the lower porous layer was prepared by simulating the structure of soft coral as the structural factors of the bionic antifouling coatings. Meanwhile, several organic antifouling components with high content contained in soft coral were added to the transparent layer and porous layer, respectively, as the component factors of biomimetic coatings. The bionic antifouling coatings, which are highly consistent with the coral structure, obtained the best antifouling performance under static and dynamic conditions. The above results provide new ideas for the synthesis of environmentally friendly bionic antifouling coatings.

Regional Difference Assessment of Comprehensive Benefit of Marine Resources Development and Utilization Based on Web GIS Technology

Regional Difference Assessment of Comprehensive Benefit of Marine Resources Development and Utilization Based on Web GIS Technology

A Reinforcement-Learning-Based Opportunistic Routing Protocol for Energy-Efficient and Void-Avoided UASNs

Underwater acoustic sensor networks (UASNs) have been used for various scenarios, such as marine exploration, and development of marine resources. However, due to the challenging underwater environment, UASNs suffers from high propagation delay, low transmission reliability and energy limitation, which pose significant obstacles to the delivery efficiency of data packets. What’s more, the sparse topology, the failure of node or link, and other factors can cause void holes, resulting in the considerable package retransmission and the low network reliability of UASNs. To this end, this paper proposed a reinforcement-learning-based opportunistic routing protocol (ROEVA) to reduce energy consumption as well as to improve the transmission reliability which also addresses the issue of void routing in underwater acoustic sensor networks. To seek optimal routing rules, a reward function based on reinforcement learning is proposed, where factors such as energy, delay, link quality, and depth information are all taken into account for appropriate routing decisions. Before forwarding the data packet, a two-hop availability checking function is defined, which can identify trap nodes and avoid routing holes. In addition, aiming to reduce packet redundancy and collisions, a waiting mechanism derived from opportunistic routing is proposed. According to the calculated Q-values, the waiting mechanism determines the priority list for packet forwarding. Evaluation results demonstrate that the proposed ROEVA protocol outperforms HHVBF, RCAR, QELAR and GEDAR in terms of energy efficiency, packet delivery ratio (PDR), average hop count, and end-to-end delay, which are analyzed by varying the number of nodes from 100 to 500.