Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.484
Filtrar
1.
J Environ Manage ; 300: 113824, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34649319

RESUMO

Despite a large body of literature on the calculations of costs of air emissions from shipping, calculations of damages to the marine water are missing. This paper calculated the costs of NOx emissions from shipping entering an environmentally heterogeneous sea by applying the abatement cost approach. The total costs and unit shadow cost of NOx were then calculated by means of the marginal abatement cost for international agreements on targets of nitrogen loads to the sea. This conceptual model highlighted the need to distinguish between direct emissions of NOx on the sea and indirect emissions through deposition of emissions on land in the catchment with subsequent transportation into the sea. Calculated total cost amounted to 240 million euros, where indirect deposition accounted for 23% of the costs. The unit shadow costs ranged between 1.41 and 3.69 euros/kg NOx-N depending on location of the vessel.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Países Bálticos , Modelos Teóricos , Navios
2.
J Acoust Soc Am ; 150(3): 1883, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34598647

RESUMO

Rapid changes in the Arctic from shifting climate and human use patterns are affecting previously reported distributions and movements of marine mammals. The underwater soundscape, a key component of marine mammal habitats, is also changing. This study integrates acoustic data, collected at a site in the northern Bering Sea, with information on sound sources to quantify their occurrence throughout the year and identify deviations in conditions and dominant soundscape components. Predictive models are applied to explain variation in sound levels and to compare the relative contributions of various soundscape components. Levels across all octave bands were influenced most strongly by the variation in abiotic environment across seasons. The presence of commercial ships did not have a discernible effect on sound levels at this location and period of time. The occurrence of sources was compared to a second site, where we documented how higher levels of shipping changed that soundscape. This study demonstrated the value of acoustic monitoring to characterize the dominant acoustic features in a soundscape and the importance of preserving soundscapes based on dominant features rather than level of sound. Using a soundscape approach has relevance for protecting marine mammals and for the food security of Alaska Native communities that depend upon them.


Assuntos
Ruído , Som , Acústica , Animais , Ecossistema , Humanos , Navios
3.
Int Marit Health ; 72(3): 155-162, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604983

RESUMO

BACKGROUND: During cruises, the management of coronavirus disease 2019 (COVID-19) infections poses serious organizational problems such as those encountered in 2020 by the Zaandam, the aircraft carrier Charles de Gaulle or the Diamond Princess. In French Polynesia, the mixed cargo ship Aranui 5 transports both tourists and freight to the Marquesas Islands. The purpose of this article is to show how COVID-19 infections were diagnosed and contained before and after passengers boarded a cruise. MATERIALS AND METHODS: On October 15, 2020, 161 passengers including 80 crew members embarked for a 13-day voyage from Papeete to the Marquesas Islands. Prior to boarding, all passengers underwent a reverse transcriptase-polymerase chain reaction (RT-PCR) test; the tests results were all negative. On Day 0, 3, 5, 8 and 11, Biosynex® rapid antigen diagnostic tests were carried out on all or some of the crew members and tourists who may have had contact with new positive cases. Each day, forehead or temporal temperatures were measured using an infrared thermometer and questions were asked concerning the subjects' health status. When a subject was positive, the person and their contacts were isolated in individual cabins. The infected person then left the vessel to be received in a communal reception centre on the nearest island. RESULTS: A total of 9 positive cases were observed, including two before departure (a tourist and a crew member). During the trip, 7 crew members tested positive. The patients and their contacts were isolated and then disembarked at the earliest opportunity. At the time of sampling, the subjects were asymptomatic. The patients and their contacts all became symptomatic within 24 to 48 hours after sampling. CONCLUSIONS: In total, the voyage could be completed without any transmission on board among the tourists and with a minimum transmission among the crew members, thus maintaining the tourist and economic activity of the islands during the times of COVID-19 pandemic.


Assuntos
COVID-19/diagnóstico , COVID-19/prevenção & controle , Medicina Naval/métodos , Temperatura Corporal , COVID-19/epidemiologia , Teste para COVID-19 , Busca de Comunicante/métodos , Humanos , Exposição Ocupacional , Polinésia , Quarentena/métodos , SARS-CoV-2 , Navios , Viagem
4.
Int Marit Health ; 72(3): 179-182, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604986

RESUMO

The increasing availability of safe and authorised coronavirus disease 2019 (COVID-19) vaccines for the first time provides the opportunity to vaccinate seafarers on board their ships while in port. Speedy vaccination of seafarers secures their health and serves to avoid the international propagation of COVID-19 virus variants via maritime traffic. As a port medical clinic, we will share our practical vaccination experience on board of merchant vessels in German/European ports with our esteemed coastal colleagues to stimulate their participation in this endeavour. You will have to adapt the procedure to your national particularities, otherwise please freely share the information with interested parties. Detailed guidance on COVID-19 vaccination in shipping and accompanying legal issues was published by the International Chamber of Shipping (www.ics-shipping.org).


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , Medicina Naval/métodos , Vacinas contra COVID-19/uso terapêutico , Humanos , Medicina do Trabalho/métodos , SARS-CoV-2 , Navios , Vacinação/normas
5.
Int Marit Health ; 72(3): 183-192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604987

RESUMO

This narrative review examines current academic literature on the mental health of Filipino seafarers working internationally, including the mental health effects of coronavirus disease 2019 (COVID-19). Framed within a rights-based approach, it aims to identify and analyse emerging themes on Filipino seafarers' mental health literature to understand what these studies potentially mean for the improvement of seafarers' education on mental health. Based on a broad selection criteria, 28 eligible papers demonstrate collectively three key findings: firstly, there is paucity in published research on seafarers' mental health; secondly, the majority of published studies are associated with a recent piracy crisis, where a significant number of mariners were attacked, taken as hostages, or killed; thirdly, three key areas emerged under which research on Filipino seafarers' mental health can be organized: the medical repatriation of seafarers, system of care for the mental health of seafarers including the diagnostic standards used, and seafarers' experiences and conceptions of mental health including the mental health effects of COVID-19. Though the bulk of the current understanding of the mental health problems is associated with piracy, several risk factors for which the quality of quantitative and qualitative evidence are patchy. The few sources of primary data to date lack focus on mental health needs which makes it difficult to grasp the extent of the problem. Developing policies and programmes for the promotion of mental health through mental health education among seafarers is important for a couple of reasons. Seafaring remains a dangerous and socially isolating occupation where work-related accidents are likely and will be potentially traumatic to mariners. Research on occupational stressors is increasingly providing evidence of their contributions to poor mental health outcomes among seafarers. Thus, mental health education of seafarers in the context of their work is important for proactive training and development.


Assuntos
COVID-19/psicologia , Saúde Mental/educação , Medicina Naval/métodos , Crime/psicologia , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Saúde do Trabalhador , Estresse Ocupacional , Filipinas/etnologia , Navios
6.
Comput Intell Neurosci ; 2021: 8901565, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659395

RESUMO

Ship radiated noise is an important information source of underwater acoustic targets, and it is of great significance to the identification and classification of ship targets. However, there are a lot of interference noises in the water, which leads to the reduction of the model recognition rate. Therefore, the recognition results of radiated noise targets are severely affected. This paper proposes a machine learning Dempster-Shafer (ML-DS) decision fusion method. The algorithm combines the recognition results of machine learning and deep learning. It uses evidence-based decision-making theory to realize feature fusion under different neural network classifiers and improve the accuracy of judgment. First, deep learning algorithms are used to classify two-dimensional spectrogram features and one-dimensional amplitude features extracted from CNN and LSTM networks. The machine learning algorithm SVM is used to classify the chromaticity characteristics of radiated noise. Then, according to the classification results of different classifiers, a basic probability assignment model (BPA) was designed to fuse the recognition results of the classifiers. Finally, according to the classification characteristics of machine learning and deep learning, combined with the decision-making of D-S evidence theory of different times, the decision-making fusion of radiated noise is realized. The results of the experiment show that the two fusions of deep learning combined with one fusion of machine learning can significantly improve the recognition results of low signal-to-noise ratio (SNR) datasets. The lowest fusion recognition result can reach 76.01%, and the average fusion recognition rate can reach 94.92%. Compared with the traditional single feature recognition algorithm, the recognition accuracy is greatly improved. Compared with the traditional one-step fusion algorithm, it can effectively integrate the recognition results of heterogeneous data and heterogeneous networks. The identification method based on ML-DS proposed in this paper can be applied in the field of ship radiated noise identification.


Assuntos
Aprendizado de Máquina , Navios , Algoritmos , Redes Neurais de Computação , Tecnologia
7.
Environ Monit Assess ; 193(10): 680, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34591192

RESUMO

Fisheries monitoring can be improved by studying the influence of gear selectivity, sampling design, and habitat conditions. We used boat-electrofishing data to investigate how sample unit placement (shoreline and channel transects) and sampling conditions (low and high flow years) affect detection of fishes in a highly regulated Ontario (Canada) river system. Species detection histories associated with a spatially replicated sampling design was fit to a Bayesian hierarchical site occupancy model for 14 fishes. Habitat (transect location) had a significant effect on detection probabilities (p) for all species, with shoreline sampling more likely to detect species than channel. Sampling year had a significant effect on detectability of six species. The relative influence of habitat and sampling year varied among species. Detection probabilities based on combined shoreline and channel transect data across both years ranged from 0.09 to 0.48 and were positively correlated to species abundance. High detection probabilities and precise occupancy estimates were associated with sunfish and bass abundant in shoreline habitats. Small-bodied species closely associated with the riverbed or exhibiting schooling behavior tended to be poorly detected. Power to detect future changes in species distribution is expected to differ based on habitat sampled, with greater power associated with shoreline boat-electrofishing. Detecting small to moderate changes is not likely for most species. The addition of channel transects did not improve the effectiveness of shoreline sampling. Improvements to the current design could be realized by reallocating sampling effort from channel to shoreline and testing different gear in deep (> 3 m) habitats.


Assuntos
Monitoramento Ambiental , Navios , Animais , Teorema de Bayes , Ecossistema , Peixes , Ontário
8.
Rev Bras Enferm ; 75(1): e20210139, 2021.
Artigo em Inglês, Português | MEDLINE | ID: mdl-34586204

RESUMO

OBJECTIVE: to analyze the activities developed by hospital ship SS HOPE in Natal. METHOD: this is a qualitative, socio-historical study, elaborated from documentary sources and 16 interviews with health professionals. Thematic Oral History was used for data treatment and analysis. RESULTS: the empirical material identified a wide schedule of courses and lectures as well as made it possible to elaborate the following categories: Health education on hospital ship SS HOPE; Legacy of international cooperation of hospital ship SS HOPE; Statements about the season of hospital ship SS HOPE. FINAL CONSIDERATIONS: the arrival and stay of this hospital ship, for ten months, is the result of negotiations between the University, the State Government and the People to People Foundation. During their stay, education and health care actions were carried out, with the joint participation of health professionals, Potiguares and Americans.


Assuntos
Cooperação Internacional , Navios , Atenção à Saúde , Pessoal de Saúde , Humanos , Pesquisa Qualitativa
9.
Comput Intell Neurosci ; 2021: 7018035, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557225

RESUMO

With the rapid development of the marine industry, intelligent ship detection plays a very important role in the marine traffic safety and the port management. Current detection methods mainly focus on synthetic aperture radar (SAR) images, which is of great significance to the field of ship detection. However, these methods sometimes cannot meet the real-time requirement. To solve the problems, a novel ship detection network based on SSD (Single Shot Detector), named NSD-SSD, is proposed in this paper. Nowadays, the surveillance system is widely used in the indoor and outdoor environment, and its combination with deep learning greatly promotes the development of intelligent object detection and recognition. The NSD-SSD uses visual images captured by surveillance cameras to achieve real-time detection and further improves detection performance. First, dilated convolution and multiscale feature fusion are combined to improve the small objects' performance and detection accuracy. Second, an improved prediction module is introduced to enhance deeper feature extraction ability of the model, and the mean Average Precision (mAP) and recall are significant improved. Finally, the prior boxes are reconstructed by using the K-means clustering algorithm, the Intersection-over-Union (IoU) is higher, and the visual effect is better. The experimental results based on ship images show that the mAP and recall can reach 89.3% and 93.6%, respectively, which outperforms the representative model (Faster R-CNN, SSD, and YOLOv3). Moreover, our model's FPS is 45, which can meet real-time detection acquirement well. Hence, the proposed method has the better overall performance and achieves higher detection efficiency and better robustness.


Assuntos
Navios , Sulfadiazina de Prata , Algoritmos , Redes Neurais de Computação , Radar
10.
PLoS One ; 16(9): e0257452, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34582459

RESUMO

OBJECTIVES: A few studies on antibody testing have focused on asymptomatic or mild coronavirus disease 2019 (COVID-19) patients with low initial anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses. Anti-SARS-CoV-2 antibody-testing performance was evaluated using blood samples from asymptomatic or mild COVID-19 patients. METHODS: Blood samples were collected from 143 COVID-19 patients during an outbreak on a cruise ship 3 weeks after diagnosis. Simultaneously, a follow-up SARS-CoV-2 genetic test was performed. Samples stored before the COVID-19 pandemic were also used to evaluate the lateral flow immunochromatographic assay (LFA) and electrochemiluminescence immunoassay (ECLIA). Titers of anti-SARS-CoV-2 IgM and IgG antibodies against the nucleocapsid and spike proteins were measured using the enzyme-linked immunosorbent assay to confirm which antibodies were influenced on LFA- and ECLIA- false-negative result in crew-member samples. RESULTS: Sensitivity, specificity, positive-predictive, and negative-predictive values of LFA-detected IgM antibodies were 0.231, 1.000, 1.000, and 0.613, respectively; those of LFA-detected IgG antibodies were 0.483, 0.989, 0.972, and 0.601, respectively; and those of ECLIA-detected total antibodies were 0.783, 1.000, 1.000, and 0.848, respectively. All antibody titers measured using ELISA were significantly lower in blood samples with negative results than in those with positive results in both LFA and ECLIA. In the patients with negative results from the follow-up genetic testing, IgM-, IgG-, and total-antibody positivity rates were 22.9%, 47.6%, and 72.4%, respectively. CONCLUSIONS: These findings suggest that anti-SARS-CoV-2 antibody testing has lower performance in asymptomatic or mild COVID-19 patients than required in the guidelines.


Assuntos
Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , COVID-19/imunologia , Adulto , Anticorpos Antivirais/imunologia , Infecções Assintomáticas/epidemiologia , Teste Sorológico para COVID-19/tendências , Teste para COVID-19/métodos , Surtos de Doenças/prevenção & controle , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Imunoensaio/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2/imunologia , Sensibilidade e Especificidade , Navios
11.
PLoS One ; 16(9): e0255401, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34492022

RESUMO

BACKGROUND: Prolonged periods of confined living on a cruise ship increase the risk for respiratory disease transmission. We describe the epidemiology and clinical characteristics of a SARS-CoV-2 outbreak in Australian passengers on the Diamond Princess cruise ship and provide recommendations to mitigate future cruise ship outbreaks. METHODS: We conducted a retrospective cohort study of Australian passengers who travelled on the Diamond Princess from 20 January until 4 February 2020 and were either hospitalised, remained in Japan or repatriated. The main outcome measures included an epidemic curve, demographics, symptoms, clinical and radiological signs, risk factors and length of time to clear infection. RESULTS: Among 223 Australian passengers, 56 were confirmed SARS-CoV-2 positive. Forty-nine cases had data available and of these over 70% had symptoms consistent with COVID-19. Of symptomatic cases, 17% showed signs and symptoms before the ship implemented quarantine and a further two-thirds had symptoms within one incubation period of quarantine commencing. Prior to ship-based quarantine, exposure to a close contact or cabin mate later confirmed SARS-CoV-2 positive was associated with a 3.78 fold (95% CI, 2.24-6.37) higher risk of COVID-19 acquisition compared to non-exposed passengers. Exposure to a positive cabin mate during the ship's quarantine carried a relative risk of 6.18 (95% CI, 1.96-19.46) of developing COVID-19. Persistently asymptomatic cases represented 29% of total cases. The median time to the first of two consecutive negative PCR-based SARS-CoV-2 assays was 13 days for asymptomatic cases and 19 days for symptomatic cases (p = 0.002). CONCLUSION: Ship based quarantine was effective at reducing transmission of SARS-CoV-2 amongst Australian passengers, but the risk of infection was higher if an individual shared a cabin or was a close contact of a confirmed case. Managing COVID-19 in cruise ship passengers is challenging and requires enhanced health measures and access to onshore quarantine and isolation facilities.


Assuntos
COVID-19/epidemiologia , SARS-CoV-2/patogenicidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Criança , Pré-Escolar , Surtos de Doenças , Feminino , Humanos , Lactente , Recém-Nascido , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Quarentena , Estudos Retrospectivos , Navios , Viagem , Adulto Jovem
12.
Rev Esp Salud Publica ; 952021 Sep 17.
Artigo em Espanhol | MEDLINE | ID: mdl-34531362

RESUMO

During the state of alert declared in the national territory in March 2020 due to the health crisis caused by SARS-CoV-2, the free movement of the population was restricted in order to prevent the spread of the virus. In the Balearic Islands, access by air and sea was limited and, in addition, health controls were established at the entry points of the islands aimed to detect people with COVID-19. The health check is understood as a Public Health surveillance procedure through which all persons authorised to travel at that time were tested. This procedure, together with the security measures to prevent the spread of the virus, had never before been implemented in the Balearic Islands and required the collaboration of various organizations in order to organise and execute it. This paper shares the experience and analysis of the health control measures implemented in these circumstances. To do so, it describes the procedure carried out, the devices that were developed, the main results and the assessment of the project as a whole. Finally, the positive aspects and possible improvements are considered. The most of people screened upon arrival in Balearics Islands did not register or show clinical symptoms of COVID-19.


Assuntos
COVID-19 , Programas de Rastreamento , Viagem , Aeroportos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Humanos , Navios , Espanha/epidemiologia
13.
Sci Rep ; 11(1): 18039, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34508144

RESUMO

To prevent the outbreak of the Coronavirus disease (COVID-19), many countries around the world went into lockdown and imposed unprecedented containment measures. These restrictions progressively produced changes to social behavior and global mobility patterns, evidently disrupting social and economic activities. Here, using maritime traffic data collected via a global network of Automatic Identification System (AIS) receivers, we analyze the effects that the COVID-19 pandemic and containment measures had on the shipping industry, which accounts alone for more than 80% of the world trade. We rely on multiple data-driven maritime mobility indexes to quantitatively assess ship mobility in a given unit of time. The mobility analysis here presented has a worldwide extent and is based on the computation of: Cumulative Navigated Miles (CNM) of all ships reporting their position and navigational status via AIS, number of active and idle ships, and fleet average speed. To highlight significant changes in shipping routes and operational patterns, we also compute and compare global and local vessel density maps. We compare 2020 mobility levels to those of previous years assuming that an unchanged growth rate would have been achieved, if not for COVID-19. Following the outbreak, we find an unprecedented drop in maritime mobility, across all categories of commercial shipping. With few exceptions, a generally reduced activity is observable from March to June 2020, when the most severe restrictions were in force. We quantify a variation of mobility between -5.62 and -13.77% for container ships, between +2.28 and -3.32% for dry bulk, between -0.22 and -9.27% for wet bulk, and between -19.57 and -42.77% for passenger traffic. The presented study is unprecedented for the uniqueness and completeness of the employed AIS dataset, which comprises a trillion AIS messages broadcast worldwide by 50,000 ships, a figure that closely parallels the documented size of the world merchant fleet.


Assuntos
COVID-19 , Controle de Doenças Transmissíveis , Indústrias , Pandemias , Navios , Humanos
14.
Sensors (Basel) ; 21(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502583

RESUMO

In recent years, the rapid development of Deep Learning (DL) has provided a new method for ship detection in Synthetic Aperture Radar (SAR) images. However, there are still four challenges in this task. (1) The ship targets in SAR images are very sparse. A large number of unnecessary anchor boxes may be generated on the feature map when using traditional anchor-based detection models, which could greatly increase the amount of computation and make it difficult to achieve real-time rapid detection. (2) The size of the ship targets in SAR images is relatively small. Most of the detection methods have poor performance on small ships in large scenes. (3) The terrestrial background in SAR images is very complicated. Ship targets are susceptible to interference from complex backgrounds, and there are serious false detections and missed detections. (4) The ship targets in SAR images are characterized by a large aspect ratio, arbitrary direction and dense arrangement. Traditional horizontal box detection can cause non-target areas to interfere with the extraction of ship features, and it is difficult to accurately express the length, width and axial information of ship targets. To solve these problems, we propose an effective lightweight anchor-free detector called R-Centernet+ in the paper. Its features are as follows: the Convolutional Block Attention Module (CBAM) is introduced to the backbone network to improve the focusing ability on small ships; the Foreground Enhance Module (FEM) is used to introduce foreground information to reduce the interference of the complex background; the detection head that can output the ship angle map is designed to realize the rotation detection of ship targets. To verify the validity of the proposed model in this paper, experiments are performed on two public SAR image datasets, i.e., SAR Ship Detection Dataset (SSDD) and AIR-SARShip. The results show that the proposed R-Centernet+ detector can detect both inshore and offshore ships with higher accuracy than traditional models with an average precision of 95.11% on SSDD and 84.89% on AIR-SARShip, and the detection speed is quite fast with 33 frames per second.


Assuntos
Radar , Navios
15.
Sensors (Basel) ; 21(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34577341

RESUMO

Currently, seaports are actively searching for methods and ways to improve their operational efficiency. Digitalization is considered as one of the main directions of current ports' development. Ports' digitalization levels are varied and may depend on different factors, including port size, traditions, turnover and handled cargo type, etc. Ports often face decision-making challenges related to assessment of their digitization level and choice of development directions. The article aims to develop a methodology to evaluate ports' digitalization level. A marketing research tool was used to collect the data needed for the analysis. A mathematical model allowing simulations is proposed and a case study of 30 ports located in the Baltic, North and Mediterranean Seas regions is explored. Based on conducted calculations, a ranking of analysed ports considering their digitalization level was created. The ports were compared within groups of small, medium-sized and large ports. It was estimated that the digitalization level in small and medium-sized ports is about 30% lower than the level of large seaports. The research results may be of interest to seaports striving to assess their level of digitalization and choose the best digital improvement solutions.


Assuntos
Computadores , Eficiência Organizacional , Coleta de Dados , Oceanos e Mares , Navios
16.
J Environ Manage ; 300: 113714, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34547570

RESUMO

Solid blasting waste generated from coating removal during ship repair and maintenance poses environmental challenges. This paper presents a review of the generation, characterization, and treatment of blasting waste in the ship repair industry. The quantities, properties, and environmental impacts of the generated blasting waste are summarized and analyzed, and the results indicate that blasting waste has a high generation rate and/or high toxicity. As alternatives to landfill, available blasting waste treatment methods include hydrometallurgical leaching, physical/physicochemical separation, thermal treatment, and direct utilization in the production of building materials. The advantages and disadvantages of these treatments are reviewed and compared. The production of building materials from blasting waste is currently attractive owning to its economic benefits and technical simplicity, whereas recycling blasting waste for high-value applications is gradually gaining research interest. The high dependence of the choice and performance of treatment methods on the waste type and characteristics is highlighted. The results emphasize the interest in conducting more research on physiochemical and thermal properties and the environmental effects of blasting waste. This review suggests that future research should focus more on paint waste management because of the restricted application of dry abrasive blasting and the development of nonabrasive blasting methods in the ship repair industry.


Assuntos
Navios , Gerenciamento de Resíduos , Conservação dos Recursos Naturais , Materiais de Construção , Pintura , Reciclagem , Resíduos Sólidos
17.
Environ Sci Technol ; 55(19): 12791-12800, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34520184

RESUMO

This work evaluates efficacies of plausible ballast water management strategies and standards by integrating a global species spread risk assessment with a policy cost-effectiveness analysis. Specifically, we consider species spread risks and costs of port- and vessel-based strategies under both current organism concentration standards and stricter standards proposed by California. For each scenario, we estimate species spread risks and patterns using a higher-order analysis of a global ship-borne species spread model and estimate fleet costs for vessel- and barge-based ballast water treatment systems for each standard. We find that stricter standards may reduce species spread risk by a factor of 17 globally and would greatly simplify the complex network of ship-borne species spread. The current policy of IMO standards is most cost-effectively achieved through ship-based treatment, and that any additional risk reduction will be most cost-effectively achieved by port-based (or barge-based) technologies, particularly if these are strategically implemented at the top ports within the largest clusters. Barge-based ballast water management would require a shift in governance, and we suggest that this next level of policymaking could be feasible for special areas designated by the IMO, by State or multistate authorities, or by voluntary port applications.


Assuntos
Espécies Introduzidas , Purificação da Água , Navios , Água , Abastecimento de Água
18.
Sci Total Environ ; 799: 149437, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34375870

RESUMO

Ship emissions problems caused by the rapid development of maritime trade can't be ignored. The NOX, SOX, CO2, PM and other toxic substances contained in the exhaust gas are extremely harmful to the environment and human health. In order to cope with the adverse effects of ship emissions and the increasingly stringent emission regulations formulated by the IMO and governments, the shipping industry needs to adopt new clean energy and high-efficiency exhaust control technologies to reduce ship emissions. This paper provides a comprehensive review, including: (1) The impact of pollutants such as NOX, SOX, CO2 and PM emitted by ships on the environment and human health; (2) New regulations about ship exhaust emissions; (3) Application of clean energy such as LNG, biodiesel, methanol, hydrogen and ammonia on ships; (4) After-treatment technology of ship exhaust gas such as SCR and EGR. And focusing on the principles, uses, characteristics, implementation obstacles and prospects of different energy and technologies, with a view to provide some help for the research on ship exhaust emissions control.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Poluentes Atmosféricos/análise , Humanos , Navios , Tecnologia , Emissões de Veículos/análise
19.
Mar Environ Res ; 170: 105440, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34333337

RESUMO

Reef-building eastern oysters, Crassostrea virginica, provide many ecosystem services, including production of valuable commercial products, formation of complex habitats, improved water quality and shoreline protection. Despite this, oyster populations have experienced dramatic declines throughout their range, spawning massive investment in management and restoration. Restoration efforts typically consider several well-studied metrics that normally influence oyster success; however, one potential factor that has not received much prior attention is submarine groundwater discharge (SGD). We conducted a series of field surveys and field experiments to explore the relationship between SGD and oysters in a marsh-lined tidal creek in Georgia, USA. SGD was mapped across multiple time points using a natural radon tracer (radon-222), and fluxes were paired with discrete measurements of oyster density, condition, size, recruitment and growth at multiple locations along the creek. Variation in oyster metrics was best explained by a combination of SGD, pH, and DO, which displayed a high degree of multicollinearity. We found an overall negative, nonlinear relationship between oyster density and groundwater flux. Interestingly, juvenile and adult condition and growth were not negatively impacted by groundwater. Rather, our results suggest that the likely mechanism for the density-flux relationship was interruption of the larval recruitment, which was also negatively related to flux. We hypothesize that larval interruption is due to the low dissolved oxygen and pH conditions of the groundwater at high flux sites. Overall, the interaction between SGD and oysters appears complex, and may be affected by other variables. This study provides evidence of a potential negative effect of a previously understudied natural phenomena on oyster demographics, and we suggest that SGD be considered in future management efforts.


Assuntos
Crassostrea , Água Subterrânea , Animais , Ecossistema , Georgia , Navios
20.
Environ Pollut ; 289: 117961, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34426196

RESUMO

Copper-containing antifouling paints (AFP) are widely used for leisure boat maintenance. Cu emitted from AFP into German surface water bodies has been suggested to be a significant source of heavy metal pollution, threatening water quality. We developed two scenarios to model Cu emissions from AFP applied on leisure boats on national scale, which allow identifying regional hotspots. The top-down approach (scenario A) was based on a previous study on national AFP consumption, while in the bottom-up approach (scenario B), median and interquartile range of Cu release rates depending on salinity conditions were considered for emission estimation. Both scenarios clearly highlighted the locally high emission pressure on inland waters in popular watersport regions, identifying these as requiring intense protection. Scenario B generally predicted lower Cu emissions (sea: 11.05-25.53 t a-1, inland: 14.15-34.59 t a-1) than scenario A (sea: 22.53 t a-1, inland: 47.97 t a-1). To evaluate their relevance, scenario results were compared to emissions modelled with MoRE (Modelling of Regionalized Emissions), which is used as reporting tool on substance emissions by Germany. According to scenarios A and B, the emission from AFP accounted for 13 % and 4-9 % of the total Cu emissions into inland waters in 2016, respectively. Scenario results were similar or higher than other emission pathways such as industrial direct dischargers. Thus, we consider Cu emissions from AFP as a significant pathway to be included in the MoRE emission inventory. We recommend scenario B for implementation as it allows a more flexible adaptation for future modelling.


Assuntos
Incrustação Biológica , Poluentes Químicos da Água , Incrustação Biológica/prevenção & controle , Cobre/análise , Monitoramento Ambiental , Atividades de Lazer , Pintura , Navios , Poluentes Químicos da Água/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...