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1
Reyff, James A. "A brief history of underwater construction noise." Journal of the Acoustical Society of America 141, no. 5 (2017): 3846. http://dx.doi.org/10.1121/1.4988574.
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Fedorovich, M. O., and A. Yu Kosmacheva. "COMPUTER MODELING OF THE SAND BODIES DEPOSITIONAL HISTORY OF THE MIDDLE JURASSIC PETROLEUM PLAY (BY THE EXAMPLE OF THE GERASIMOVSKOE FIELD, WESTERN SIBERIA)." Geology and mineral resources of Siberia, no. 4 (2020): 8–13. http://dx.doi.org/10.20403/2078-0575-2020-4-8-13.
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The present paper describes the DIONISOS software package (Beicip-Technologies), where the reconstruction of the accumulation conditions and facies modeling of sand reservoirs Yu10, Yu9, Yu8, Yu7 and Yu6 of the Tyumenskaya Formation and carbonaceous-clay members acting as fluid seals within the Gerasimovskoye oil and gas condensate field located in the south of the Parabel district of the Tomsk region. Reconstructions of facies environments make it possible to consistently restore conditions and create a general principled model of the accumulation of sandy-argillaceous deposits of the Middle Jurassic PP in a given territory. Polyfacies deposits of the Bajocian are represented by sands of distributaries and stream-mouth bars, underwater slope of delta, above-water and underwater delta plains, argillaceous-carbonaceous sediments of floodplain lakes, bogs, marshes and lagoons, clays formed at the border of the above-water and underwater deltaic plains, silt deposits of above-water and underwater delta plains, prodelta clays. As a result of the 3D facies model construction, it is shown that the subcontinental sedimentary environments of sand reservoirs Yu10–Yu8 are replaced by deltaic and floodplain-lacustrine-boggy ones, and the formation of Yu7–Yu6 reservoirs occurs in conditions of coastal plain, periodically flooded by the sea. In total, 5 lithotypes of sand deposits have been identified, 1 – argillaceous-carbonaceous, 2 – argillaceous and 1 – silty. Computer facies 3D modeling of the sand bodies assemblage (hydrocarbon reservoirs) of the Bajocian age for the Gerasimovskoye oil and gas condensate field has been performed.
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Meijer, Fik, and André Wegener Sleeswyk. "On the construction of the ‘Syracusia’ (Athenaeus V. 207 A-B)." Classical Quarterly 46, no. 2 (1996): 575–78. http://dx.doi.org/10.1093/cq/46.2.575.
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It is perhaps significant that one of the more informative texts on ancient shipbuilding predates the period in which Greco-Roman shipping flourished. It is Homer's description of how Odysseus built a ship () on the island of the nymph Calypso, with which he intended to return to his native island of Ithaca (Od. 5.244–57). The text is of exceptional interest because it gives as early as the eighth century B.C. a stepby- step description of the tenon-and-dowel ‘shell-first’ method typical of Greco- Roman ship-building, which has been so amply confirmed in the last few decades by underwater archaeology in the Mediterranean.
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Zhang, Song, Ming He, Guoliang Dong, and Xianying Wang. "New Perceptions of Ancient Commerce Driven by Underwater Ancient Site Investigations: A Case Study of Xinfeng River Basin." Heritage 7, no. 5 (2024): 2313–47. http://dx.doi.org/10.3390/heritage7050110.
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In the 1950s and 1960s, to address the flooding issues and power shortage that hindered national construction, the Xinfeng River hydropower plant was planned and built to prevent floods, store water, and generate electricity. Consequently, many ancient ruins in the study area were drowned, including ancient post roads, channels, villages, towns, bridges, and other relic sites. By checking historical data and adopting integrated underwater acoustic detection, we conducted a comprehensive cultural-relics survey on the flooded area under Wanlv Lake in the Xinfeng River Basin. A side-scan sonar detection of the underwater relics within the flooded area confirmed the spatial distribution of cultural relics in the Xinfeng River Basin. It portrayed ancient people’s production and life scenarios, outlined the migration and trade history within the region and beyond, and contributed to the enrichment of the literature and understanding of ancient shipping and trade in the basin.
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Ivce, Renato, Matej Grubiša, and Darijo Mišković. "Protection Coatings for the Underwater Part of Ship’s Hull." Journal of Maritime & Transportation Science 55, no. 1 (2018): 59–70. http://dx.doi.org/10.18048/2018.00.04.
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In this article authors present a general consideration of the underwater part of ship’s hull protection by protective coatings, paying particular attention to antifouling paints. Following the presentation of the importance of ship’s hull maintenance and protection in order to make navigation safer and to keep the ship in operation for as long as possible, a summary is made of the main types of antifouling products used throughout the history up to the present time. As far back as a thousand years BC, people had developed techniques to protect objects from falling into disrepair and understood the importance of preserving construction materials in order to prolong their useful life and value. Marine industry has been developing day by day and attention is increasingly focused on the safety of ships and crews, as well as on the protection of marine environment. Tin-free self-polishing copolymer (SPC) and foul release technologies are currently applied, in addition to many alternative solutions being suggested. Modern approaches to effective environment-friendly antifouling systems and their performance are highlighted.
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Alhourani, Abdulla, Mohammad Nazzal, and Basil Darras. "Submerged Friction Stir Back Extrusion of AZ31 Magnesium Alloy." Key Engineering Materials 933 (October 17, 2022): 78–87. http://dx.doi.org/10.4028/p-9i4odm.
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Friction Stir Back Extrusion (FSBE) is a new grade of severe plastic deformation process capable of producing metallic tubular geometries that exhibit ultrafine grain structure and superior mechanical properties. FSBE of tubular sections provide opportunities for producing lightweight rigid structures for the automotive, aerospace and construction industries. This research investigates the effect of submerging conditions (in water at 25 °C and 2 °C) for Magnesium AZ31-B tubes on the grain size, mechanical properties, temperature history and power consumption. Submerged FSBE is compared to FSBE in air at fixed process parameters of 90 mm/min and 2000 rpm. It is shown that the impact of submerging is statistically insignificant in terms of the mechanical properties, ultimate tensile strength and percent elongation, of the produced tubes according to the conducted t-tests. On the other hand, the optical microscopy results indicated finer grains at the inner wall of the seamless tubes for FSBE in air and underwater FSBE at 25 °C when compared to underwater FSBE at 2 °C.
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Omar, Priyanka, MVN Siva Kumar, and Subbarao Yarramsetty. "Management of Various Safety Parameters in Tunnel Construction: A Critical Review." E3S Web of Conferences 170 (2020): 06003. http://dx.doi.org/10.1051/e3sconf/202017006003.
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Population is growing rapidly and so are vehicles on roads. This leads to enormous need of tunnels and subways for easy locomotion and mobilization. From conventional tunnels, for sewage and water facilities to modern electrified tunnels, for mass transit and underwater highways, method of construction of a tunnel to its safety inspection and maintenance has taken a wide leap. Tunnel construction requires wide range of resources like human, technology, machinery, materials, energy, and finance. To handle all these resources simultaneously becomes complex and requires good management. Even with good management, accidents and hazards might occur. A critical review of various safety parameters while constructing a tunnel and its management is presented in this paper. This review paper discusses the history of safety of tunnels till present safety measures and techniques adopted around the world for different tunnels; various critical factors which affect the safety in tunnels; the extent of damage occurring due to these factors; numerous preventive measures which are adopted around the world to prevent loss of property and lives in tunnels; and advanced technology and software, which are being used in modern era to enhance safety in tunnel construction. The study from manual horse drawn-tramway to autonomous robotic system has been done. This paper also considers various tunnels around the world and gives a summary of factors for safety focused on for making these tunnels, with its adopted remedy.
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Carrick, F., H. Peereboom, and G. Thompson. "Success of Enclosures Featuring Innovative Design Features for Public Display of Platypuses." Australian Mammalogy 20, no. 2 (1998): 300. http://dx.doi.org/10.1071/am98301.
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The history of public displays of platypuses has often not been a happy one for the platypuses concerned; however, there are also some examples of success. Although other approaches to keeping platypuses in captivity have been developed, most of the interesting things which platypuses do occur underwater, and a properly designed and engineered structure provides the opportunity for much larger numbers of people to see platypuses than in open situations. The construction of displays at Brisbane Forest Park and Fleay's Wildlife Park incorporates several innovative features, but at least as importantly, a management approach which fundamentally allows the platypus to come and go from the display area as it pleases, has been implemented. There are now several years experience with these facilities and the successful maintenance of their residents.
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Medaglia, Salvatore, Fabio Bruno, Ana Castelli, et al. "Archival Research, Underwater Optical Surveys, and 3D Modelling: Three Stages for Shaping the Wreck of the Steamship Bengala (Isola di Capo Rizzuto, Crotone, Italy)." Heritage 8, no. 1 (2024): 13. https://doi.org/10.3390/heritage8010013.
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Bengala, a steamer that sank in 1889 near Capo Rizzuto, Italy, was a relatively new vessel for its time, with an unusually short 18-year service life, given that steamers of the period typically operated for 30 to 40 years. Despite its brief history, SS Bengala played a significant role in the development of Italy’s young merchant navy, undergoing multiple ownership changes and serving various Italian shipping companies. Employed mainly along the route to Southeast Asia, it transported Italian migrants overseas and also participated in troop raids during the Italian military expedition to Eritrea in 1887. Despite its historical significance, no iconographic material has yet been found to depict SS Bengala, and archival research conducted in Italy and England has not uncovered any naval plans, photographs, or drawings of the ship. To overcome this gap, the authors employed new technologies and historical information to create a virtual reconstruction. This research combined archival sources with underwater surveys, including a detailed 3D survey by divers and archaeologists. Archival research, including consultation of official documents, provided critical information on the ship’s dimensions, superstructure, rigging, materials, and construction methods. The 3D modelling of the ship’s external hull, based on precise geometric data from the wreck site, offers a first step towards virtual reconstruction. The modelling is grounded in photogrammetric surveying techniques, ensuring high accuracy in the reconstruction process. The model can be used in augmented reality (AR) applications to enhance underwater exploration, allowing divers to visualise the reconstructed ship in its original environment. Additionally, it supports museum exhibits, interactive visualisations, and educational games, making it a valuable resource for engaging the public with maritime history and archaeology.
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Chapuis, Robert P., Jacques Lavoie, and Doris Girard. "Design, construction, performance, and repair of the soil–bentonite liners of two lagoons." Canadian Geotechnical Journal 29, no. 4 (1992): 638–49. http://dx.doi.org/10.1139/t92-071.
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A sand–bentonite mix was used to form the liner of four lagoons for the La Tuque and Haute-Mauricie sewage water treatment project. This paper describes the site conditions, design, and construction of the lagoons. Since the results of the control tests on the sand–bentonite were satisfactory, it was expected that the liner would be as impervious as it was designed to be. Such control tests, however, provide local values that can give only an indirect prediction of the waterproofing of each lagoon. The global performance was evaluated in 1988, after filling the lagoons, by comparing their leakage rates with the design theoretical values. The performance of two of the lagoons was satisfactory, whereas the two other lagoons lost 10 times more water than the maximum leakage rate allowed in the specifications. An analysis of the various factors influencing the global performance is developed to explain these contradictory performances, which cannot be explained by the usual deterministic method used in design. The paper demonstrates how to analyze the graph of the total leakage rate of a lagoon to determine where the main hydraulic defects are located and whether or not they are deteriorating. Several techniques for repairing the lagoons were considered and are described. The technique selected was the underwater injection of a bentonite slurry of adequate viscosity. Repairs were successfully completed during the summer of 1989. Key words : impervious liner, soil, bentonite, permeability, case history.
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Nikolić, Marko, and Jelena Šćekić. "Cultural and natural heritage of Djerdap: Lost history or potential for sustainable development?" Arhitektura i urbanizam, no. 55 (2022): 24–37. http://dx.doi.org/10.5937/a-u0-37943.
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The Roman Limes, the former natural border of the Roman Empire, has been recognized as a cultural landscape with exceptional universal values of international importance by the relevant organization for the protection of cultural and natural heritage - UNESCO. The Danube River is an integral part of the Roman Limes, a testimony to the culture and traditions of the peoples who lived on the banks of the Danube, as well as cultural heritage in general. Within the part of the Danube River that passes through the Republic of Serbia, the Djerdap segment stands out. It includes sites of different historical periods (prehistoric, ancient and medieval) and is significant cultural heritage on an international level. However, most of the sites are underwater as a result of the construction of the Djerdap Hydroelectric Power Plant. Consequently, insufficient access to its cultural heritage has led to its insufficient presentation and promotion, but also a lack of information about the existence of the cultural heritage. Therefore, the main goals of this paper are to spread knowledge about Djerdap's cultural and natural heritage, to promote its importance, to identify potential for integrating the cultural heritage into contemporary trends through the affirmation of cultural routes, and to establish sustainable development of the cultural landscape. The results of the research are presented through an urban architectural project that represents the sublimation of critical attitudes formed with regard to the protection, presentation and promotion of cultural heritage. The project draws from a literature analysis, case studies and examples of good practice relevant to the research. The expected results of the research include raising awareness of the importance of Djerdap's cultural heritage through promoting a cultural route and forming a potential model for the use of its cultural heritage in the process of establishing sustainable development of the cultural landscape.
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Shcherbakov, V. S., S. V. Kulichkov, and P. S. Minakova. "Additive technologies application for repairing and restoring elements of submarine pipelines." ТЕНДЕНЦИИ РАЗВИТИЯ НАУКИ И ОБРАЗОВАНИЯ 104, no. 13 (2023): 195–98. http://dx.doi.org/10.18411/trnio-12-2023-752.
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The introduction of additive technologies in the oil and gas industry has just begun and is at the initial stage of the possible introduction and expansion of additive manufacturing in the oil and gas industry. The article provides a brief introduction to additive manufacturing in the repair of an underwater pipeline in an oil and gas area, and summarizes the state of development and scope of additive manufacturing technologies on the example of foreign companies. This article provides an overview of robotic use for underwater pipeline repair.
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Sun, Yang, and Bo Hua. "Structure Research of Resistance Shunt Type Piezoelectric Composite and Underwater Sound Absorption Performance Analysis." International Journal of Acoustics and Vibration 28, no. 4 (2023): 403–19. http://dx.doi.org/10.20855/ijav.2023.28.41983.
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The high-efficiency sound absorption of underwater sound-absorbing materials under "low frequency" and "wide frequency" conditions has become a hot topic in current research. Underwater semi-active sound absorption can help to improve low frequency sound absorption performance by designing the structure of the piezoelectric composite and the shunt circuits, and it is also advantageous due to its simplicity, compactness, ease of installation, low cost, and high stability. In this paper, a kind of resistance shunt type piezoelectric composite is designed, and its underwater sound absorption performance is analyzed. Theoretical analytical formulas and finite element numerical calculation are used to calculate the electro-elastic constants of the piezoelectric composite. The theoretical model based on the Mason equivalent circuit and transfer matrix theory is used to calculate the sound absorption coefficient. Through the study of 0-3 and 1-3 composites used in the existing research work, it was found that the piezoelectric composite which is suitable for resistance shunt type underwater semi-active sound absorption should have a low longitudinal wave velocity and high electromechanical conversion coefficient. According to this design objective, the structure of the piezoelectric composite has been gradually modified, and finally it is determined that the sparse oblique 2-1-3 composite is an appropriate type of piezoelectric composite. Theoretical calculations and simulation experimental measurement verifies that when the inclination angle is 21 deg and the shunt resistance is 10 kOhm or the inclination angle is 24 deg and the shunt resistance is 10 kOhm, the sound absorption coefficient within the low frequency band 1--3~kHz can be significantly improved.
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Stablichenkova, Dasha. "A Study of the Accuracy of Positioning in a Network of Wireless Underwater Sensors Depending on the Genetic Algorithm." Galoitica: Journal of Mathematical Structures and Applications 9, no. 1 (2023): 22–30. http://dx.doi.org/10.54216/gjmsa.090203.
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Wireless Sensors Networks (WSNs) are a scientific revolution in wireless communications and embedded systems. WSN is based on the idea of abandoning the human factor, which was often an obstacle because it was not possible to be in the places where these networks are placed, especially if the collection of information required a long time, Underwater wireless sensor nodes can be deployed for monitoring, exploration, and for disaster protection, and this is what is called Underwater Wireless Sensor Networks (UWSNs). nIn this paper, we will study how the parameters of the genetic algorithm change when locating sensors under water, Including the error rate, the number of nodes in the network and the time taken to implement.
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Soma, Katrine, Peter Verweij, Elesiër Angel, and María A. Naranjo. "Inclusiveness in the Caribbean-Locals’ Perceptions about Nature, Tourism and Recreation in Bonaire." Sustainability 14, no. 21 (2022): 14167. http://dx.doi.org/10.3390/su142114167.
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The economies of small tropical islands often benefit from large-scale tourism, attracted by the guarantee of beach facilities, sun and warmth, landscape beauty, and cultural and underwater life. While these are highly valued assets, it is unclear how local communities benefit from tourism, or how they perceive their natural environment, which has been the basis for their rich cultural history. Against this background, the main aim of this article is to investigate inhabitants’ perceptions about locals’ inclusiveness in tourism and recreation on a small island called Bonaire. A total of 400 households were interviewed during the period November 2021–February 2022. Inclusiveness in tourism and the welfare it brings are judged as low, based on the findings in this study. With a share of around 40% of the population of Dutch Caribbean islanders living in poverty, the challenge of inequality is urgent. While environmental degradation contributes to inequality, inequality can also contribute to environmental degradation. To reduce inequalities, while ensuring life below water and life on land, the handling of poverty is one of the most critical bottlenecks in this society.
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Chen, Zhimin, Daren Zhou, Jingjun Lou, et al. "Experimental Validation of Reconstruction of Sound Source Radiation in an Underwater Half-Space Bounded by a Water-Air Interface." International Journal of Acoustics and Vibration 29, no. 1 (2024): 80–85. http://dx.doi.org/10.20855/ijav.2024.29.12024.
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When a vibrating structure is located in a half-space bounded by a reflecting surface, the measured sound pressures are polluted by the reflection, so that they cannot show the actual sound radiation from the structure. The half-space spherical wave function expansion-based near-field acoustical holography approach is proposed to reconstruct the direct radiation from the sound source using the polluted sound pressures, which has been validated by numerical simulations. This paper deals with the experimental validation of this approach applied in an underwater half-space bounded by a water-air interface. The sound pressures measured in the half-space are used as the input data. The reconstructed sound pressures obtained are compared with benchmarks measured in a free space. The results indicate that the influences of the water-air interface reflection on the measured sound pressures can be greatly reduced in the entire frequency range investigated. The normalized relative reconstruction error introduced by the parameters of the hydrophone array and the water tank in the experiment is analyzed. The results of the experimental validation show that the proposed approach is promising for accurately measuring sound signals radiated from manned or unmanned vehicles or equipment underwater near a water-air interface.
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Lepskiy, Maxim. "Dutch Navigation Model of Decision Making." Newsletter on the Results of Scholarly Work in Sociology, Criminology, Philosophy and Political Science 3, no. 1 (2022): 58–75. http://dx.doi.org/10.61439/seeh6417.
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In the contemporary consumer-oriented world, where desire often outweighs rationality, there is a growing significance attributed to specific-historical decision-making models, among which the Dutch navigational model stands out. The article explores the primary dimensions of importance and universality inherent in decision-making mechanisms within human life. Specifically, it examines the case of the historical-cultural, semantic, and environmental legacy of the East and West India Company in Amsterdam through the application of visual sociology techniques related to the environment and decision-making culture in the field stage. The examination of culture and the decision-making process, particularly within historical expansion processes as a scaling of outcomes, is intertwined with crucial dimensions of decision-making. These include aspects related to activity, volition, personal-status (social-power) attributions, and the consequential significance of decisions as agents shaping fate in history. Political-strategic decisions made collectively at the highest echelons were harmonized through a unified command structure with hierarchical elements, adherence to the ship's charter, the rationality inherent in navigational logic, and a system celebrating the success of the ship's crew upon the venture's completion. The core of the navigational decision system revolved around key inquiries that mirrored crucial stages of decision-making: Where am I (reconnaissance)? Where do I want to go (goal setting)? Which direction to go (orienteering)? How do I get there (tactics and ship navigation)? Multimedia thinking, characterized by visual clarity and the openness associated with terrestrial geography, necessitated the integration of virtual marine geography. This marine geography not only reflected concealed but quantifiable underwater factors but also aligned with the invisible environment, reconstructed on maps. Additionally, it harmonized with subjective-architectural construction cartography, collectively fostering flexibility in decision-making.
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Skrzyński, Stanisław, and Grzegorz Grzeczka. "Studies on Saturation Diving in Poland and Practical Application of Their Findings. Part 2 C. Developing a Polish System of Saturation Diving in the 1980s and 1990s." Polish Hyperbaric Research 81, no. 4 (2022): 69–92. http://dx.doi.org/10.2478/phr-2022-0021.
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Abstract This article is another in a series of articles on the research and the deployment of saturation diving technology in our country. This part discusses Polish specificities and achievements against the background of economic and historical context. It describes the creation of the base for saturation diving in the times of economic hardship in our country. Over this period, the shipbuilding industry was driving saturation diving research as a basis for the construction of diving systems to be exported to secure the extraction of the resources from the sea shelf. This paper describes the efforts of the animators and protagonists of underwater research in our country, whose work is continued to this day. In its second part the author shows how the Polish system of saturation diving was created. The article also considers the technical and organisational conditions in which the first saturation dives took place and the history of the development of the Polish decompression method for saturation diving. A key role in this difficult task was played by the creation of a base for this industry and research potential, assisted by the relevant state agencies, dedicated for the defence sector. A multiannual National Research and Development Plan (Polish abbr. CPBR) was set up with objectives 9.2 and 9.5 focused on medical and technical research resulting in the development of a diving system with its organisational framework, medical safety solutions, and reliable technology. The outcomes of this programme are still being implemented today. Despite advances in the medical and technical fields as well as organisation, the problems of saturation diving are still pertinent because, regardless of its complexity and high cost, this is the most efficient diving format that allows for very deep diving operations, currently up to 400-500m.
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Skrzyński, Stanisław, and Grzegorz Grzeczka. "Studies on Saturation Diving in Poland and Practical Application of Their Findings. Part 2 b. Developing a Polish System of Saturation Diving in the 1980s and 1990s." Polish Hyperbaric Research 80, no. 3 (2023): 8–22. http://dx.doi.org/10.2478/phr-2022-0013.
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Abstract This article is another in a series of articles on the research and the deployment of saturation diving technology in our country. This part discusses Polish specificities and achievements against the background of economic and historical context. It describes the creation of the base for saturation diving in the times of economic hardship in our country. Over this period, the shipbuilding industry was driving saturation diving research as a basis for the construction of diving systems to be exported to secure the extraction of the resources from the sea shelf. This paper describes the efforts of the animators and protagonists of underwater research in our country, whose work is continued to this day. In its second part the author shows how the Polish system of saturation diving was created. The article also considers the technical and organisational conditions in which the first saturation dives took place and the history of the development of the Polish decompression method for saturation diving. A key role in this difficult task was played by the creation of a base for this industry and research potential, assisted by the relevant state agencies, dedicated for the defence sector. A multiannual National Research and Development Plan (Polish abbr. CPBR) was set up with objectives 9.2 and 9.5 focused on medical and technical research resulting in the development of a diving system with its organisational framework, medical safety solutions, and reliable technology. The outcomes of this programme are still being implemented today. Despite advances in the medical and technical fields as well as organisation, the problems of saturation diving are still pertinent because, regardless of its complexity and high cost, this is the most efficient diving format that allows for very deep diving operations, currently up to 400-500m.
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Amri, Ulil. "Recent Sediment Analysis, Study Case: Sub Bottom Profiler Data Line 8 Geomarine Research Vessels." Journal of Wetlands Environmental Management 7, no. 2 (2019): 123. http://dx.doi.org/10.20527/jwem.v7i2.171.
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<p>North Aru Island’s offshore had a long exploration history since 1973 until present. The characteristics of seabed can be studied through the shapes, acoustic reflection pattern, type of substrate or sediment, or by living organisms at the seafloor. In Indonesia, the sub-bottom profiler data was previously only used to measure sea depth. This study was expected to provide overview and updated information about sea depth, seabed and sedimentary layers characteristics based on generated acoustical reflection values and to identify information about abiotic compounding seabed (grain size) used methods Folk 1974 and Spread. Resulted bathymetry data could explain the depth and topography of study areas, seabed characteristics, sea bed sediment classification that were expected to support the determination of shipping tracked lines, underwater pipelines construction, and to determine mineral compounds in the deep sea. The obtained data of field records were in digital *.odc format that is a standard format for BATHY-2010 software. In order to simplify data processing, there would be a series data conversion process into other formats. Data processing of sub-bottom profiling was conducted by Kogeo-imaging software. For more clear and better look than the playback data, the processing data was undergone some steps of treatments such as filtering, stacking and additional gain. Moreover, those data were interpreted at once time with digitizing to interpreted sediment layers. The sea depth of research location was around 52.59-97.03 below the sea surface. Sea bottom formed land (flat) was in the eastern part of the location. Steep basin or Aru Trough was in the western with type substrate of gravelly mud. In general, recorded seismic cut (section) was in the time domain which created vertical velocity distortion and lateral that would produce seismic records that would be different with its actual. Seismic only enabled to detect lithology border if there any acoustical impedance exchange which would be bigger than detectable limit of used seismic waves.</p>
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Liu, Weixing, Zihan Xia, Linyan Wu, et al. "Underwater remotely operated vehicle control system with optimized PID based on improved particle swarm optimization." DESALINATION AND WATER TREATMENT 314 (2023): 322–29. http://dx.doi.org/10.5004/dwt.2023.30037.
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Zhu, Wei, Mingsu Shen, Shixin Dai, Kuanning Liu, and Yongdi Qi. "Channel Evolution under the Control of Base-Level Cycle Change and the Influence on the Sustainable Development of the Remaining Oil—A Case in Jiang Ling Depression, Jiang Han Basin, China." Sustainability 14, no. 19 (2022): 12518. http://dx.doi.org/10.3390/su141912518.
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The extension of river channels is one of the key factors in determining the remaining oil distribution. Different sedimentary facies and bedding types of oil layers will form specific characteristics of remaining oil distribution after water injection development. Using massive drilling, core, logging, seismic, and production data, on the basis of sequence stratigraphy base-level cycle change, the river records and development history are restored, and the fine connectivity of reservoirs and the configuration relationship of production wells are studied. The following conclusions are drawn: (1) A sequence stratigraphic division scheme is established. In the established sequence framework, the types and characteristics of reservoir sand bodies are analyzed. The 2nd and 6th members of Yu yang formation can be divided into 2 long-term base level cycles, 5 medium-term base level cycles, and 17 short-term base level cycles. The evolution of the second and sixth members of the Yu yang formation shows a pattern of base level rising, falling and rising again; (2) the vertical sedimentary evolution sequence is underwater distributary channel distributary channel meandering channel distributary channel flood plain. The types of channel sand bodies developed from little overlap to more vertical or lateral overlap and then gradually changed to isolated type; (3) according to the structural location and development sequence, different types of reservoirs are identified. Combined with the statistics of the drilled data of Yu yang formation k2y4 in Fu I fault block, it is found that the connectivity rate of oil layer thickness (the ratio of oil layer connectivity thickness to total thickness of sand layer) within the oil-bearing area is 84.4%, and the connectivity rate of the number of layers (8) is 60%. The connectivity condition is relatively good.
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Kang, Ha Neul A. Reum, and Mi-Hwa Hong. "Relationship among Water Safety Incidents, Aquatic Anxiety, and Intention to Continuous of Elementary School Students Participating in Survival Swimming." Korean Society for Leisure Sciences 15, no. 1 (2024): 43–53. http://dx.doi.org/10.37408/kjls.2024.15.1.43.
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This study purpose to investigate the relationships water safety incidents, aquatic anxiety, and intention to continuous of elementary students participating in survival swimming. The study participants 358 elementary grades 3 to 6 experience participating in survival swimming. Statistical analysis using the SPSS, AMOS. The analysis included reliability, correlation, exploratory factor, confirmatory factor analysis, and structural equation modeling. First, aquatic safety incidents were found to be partially influenced by aquatic anxiety. Second, aquatic safety incidents were found to partially affect the intention to continue. Third, aquatic anxiety was found to partially influence the intention to continue. Conclusion, It can be understood that elementary school students participating in survival swimming should receive pre-education on water safety incidents related to swimming pools/water parks, boats, water safety education, in order to reduce underwater anxiety and sustain survival swimming. Comparing the intention to continuous in survival swimming based on pre-swimming experience, it would greatly contribute to the activation of survival swimming.
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Foster, Cheryl, Heather McKillop, and E. Cory Sills. "SEA-LEVEL RISE AND SETTLEMENT AT EK WAY NAL: CORING THE PAST." Research Reports in Belizean Archaeology 18 (2023): 365–74. http://dx.doi.org/10.62064/rrba.18.31.
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Excavations in the spring and summer of 2022 were carried out at the underwater ancient Maya salt work of Ek Way Nal in Punta Ycacos Lagoon, Paynes Creek National Park, Belize. Ek Way Nal provided salt to the ancient Maya during the Late and Terminal Classic periods (600-900 C.E.). In additional to excavations in buildings at the site, a 1 X 2 m unit was excavated to extract a sediment column for examining the relationship between the ancient Maya settlement at Ek Way Nal and sea-level rise. In this article, the excavations, extraction of the sediment column, and processing it for laboratory analyses are described. Field observations are discussed. Fine red mangrove root (Rhizophora mangle) and charcoal samples were extracted from the sediment column for radiocarbon dating. The results from the datum core excavation indicate that sea-level rise occurred before, during, and after the ancient Maya occupation at Ek Way Nal.
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Hendricks, Waldon, and Boniface Kabaso. "A Framework for Selecting Optimal Network Protocols for IoT Technologies in Image and Vision-based Applications." International Conference on Artificial Intelligence and its Applications 2023 (November 9, 2023): 6–14. http://dx.doi.org/10.59200/icarti.2023.002.
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The growth of Internet-of-Things (IoT) technologies and the rapid advances in image- and video-based applications make it necessary to select the most appropriate network protocols that ensure reliable, efficient and robust system performance. This study presents a framework to help select appropriate network protocols for Narrowband IoT applications. This framework evaluates and compares the most popular wireless and wired IoT technologies, especially Narrowband IoT (NB -IoT) and 5G, based on their characteristics, strengths and limitations. The research considers factors such as latency, bandwidth, scalability, energy efficiency and reliability to determine the suitability of these protocols for each application area. This study investigated the performance of these technologies in different environments, including underwater, airborne and land environments. By providing a structured approach to selecting the optimal network protocol for specific applications, this study aims to streamline and improve the deployment and performance of IoT technologies in various industries. While this study offers comprehensive insights into the optimal selection of network protocols for various IoT applications, it primarily focuses on popular technologies and does not account for emerging technologies.
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Sills, E. Cory, and Heather McKillop. "THE IMPORTANCE OF USING SEDIMENT CHEMISTRY TO INTERPRET ANCIENT MAYA SALT MAKING ACTIVITIES AT THE PAYNES CREEK SALT WORKS." Research Reports in Belizean Archaeology 18 (2023): 347–54. http://dx.doi.org/10.62064/rrba.18.29.
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Chemical analysis of soils and sediments are useful for finding activities and defining space not readily apparent in the artifact assemblage due to varied preservation. In the Maya cultural area, chemical analysis of anthropogenic and naturogenic terrestrial soils and marine sediments have been used to find activities that occurred at ancient Maya sites both inside and outside of buildings. The Underwater Maya project has adapted soil chemistry, usually conducted at terrestrial sites, to the submerged Paynes Creek Salt Works. The acidic red mangrove peat has remarkably preserved wooden posts that form the outline of buildings and botanical remains but does not preserve bone or shell. The differential preservation at the salt works could obscure the full plethora of activities taking place, under shadowing the complexity of production of salt for the Late Classic Maya. In this paper, we discuss the importance of soil and sediment chemistry analysis in the Maya are, methods for sampling sediment at the Paynes Creek Salt Works, and the chemical signatures of human activity that are most likely to occur at the salt works.
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Platov, Illia, and Oleksii Pavlovskyi. "VERTICAL MOTION OF MINIATURE WALKING ROBOTS. STATE OF THE PROBLEM REVIEW." Bulletin of Kyiv Polytechnic Institute. Series Instrument Making, no. 65(1) (June 30, 2023): 96–103. http://dx.doi.org/10.20535/1970.65(1).2023.283444.
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The article reviews the state of the art of developing miniature walking robots for vertical movement due to friction forces between limbs and surface. In particular, special attention is paid to miniature walking robots - hexapods, as they have good stability and cross-country ability compared to other types of robots, both wheeled and tracked. Unlike other types of robots, hexapods can be fully autonomous. This makes them a potentially versatile tool for solving a variety of tasks in different areas, such as: 1) rescue operations - hexapods can penetrate destroyed buildings to assess the condition under the rubble, explore underwater spaces, and generally move in places where there is not enough space for movement and complex maneuvers; 2) military use - hexapods can clear mines, be used for reconnaissance or surveying, while saving lives due to the possibility of complete autonomy; 3) industrial applications - due to their maneuverability and cross-country ability, hexapod robots can become indispensable in quarries and construction sites where there are slopes, mountainous terrain, and generally where wheeled or tracked robots cannot easily move; 4) speleology - search and exploration of minerals inside caves, mines, etc; 5) accident response, in particular, in the nuclear power industry.
 Despite the long history of development and significant progress in this area, thanks to which many design solutions and modernizations are already known, the problem of vertical movement of small hexapod robots due to friction forces still remains unsolved.
 Existing developments are usually aimed at moving on surfaces by imitating the limbs of biological creatures (insects, animals, etc.), which allows robots to climb upwards thanks to an adhesive substance, grip the surface with mechanical claws, etc. Magnet and suction cup designs have also been known for a long time, but this solution requires a very powerful power source and is not universal.
 Therefore, one of the most promising areas of research is the vertical movement of hexapod robots due to friction forces between the limbs and the surface, since the robot remains autonomous and does not require special equipment and additional communication with a power source (compressor, etc.), and, more importantly, is able to move both on horizontal and vertical surfaces.
 At the moment, there are several examples of successful use of hexapods for vertical movement, but the review of works has shown that the problem of vertical movement of miniature hexapod robots remains relevant and requires further research and development. Existing achievements in this area give us hope that in the future we will demonstrate effective solutions to this problem and the widespread use of hexapods in various industries and science.
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Shuisky, Yu D., G. V. Vykhovanetz, and A. B. Murkalov. "CLASSIFICATION OF ANTHROPOGENOUS RELIEF FORMS WITHIN COASTAL ZONE OF UNTIDAL SEAS IN EUROPE." Odesa National University Herald. Geography and Geology 27, no. 2(41) (2023): 83–97. http://dx.doi.org/10.18524/2303-9914.2022.2(41).268703.
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Problems Statement and Purpose. The article defines the intensification of the development of anthropogenic geomorphology as one of the important areas of geographical science in Ukraine. Until now, there is practically no geomorphological classification of anthropogenic relief forms in the coastal zone of the seas and on the coasts in fundamental works. This significantly inhibits the further development of this scientific direction and adversely affects practical factors. Review and analysis of the history of research on the development of anthropogenic geomorphology showed the beginning of the occurrence of anthropogenic relief many centuries ago. But this was addressed by only a few geographers and representatives of the authorities. Only with the advent of machine production and the progress of modern coastal development, geomorphologists recognized a separate morpholithogenesis. Even today, foreign authors generally pay little attention to geomorphological issues of the study of anthropogenic relief on oceanic and sea coasts. Data and Methods. Mainly own experience of geomorphological studies in different European countries was used. Additional material is borrowed from publications of domestic and foreign authors supplemented with illustrations. Synthesis, classification, comparative and geographic as well as cartographic methods are used. Actual illustrative and graphic materials are included. Results. The first attempt to classify the anthropogenic relief on the sea coasts of the non-tidal seas of Europe (Mediterranean, Black, Azov) in several groups is outlined according to purposes: a) port; b) navigational; c) coast guard; d) recreational; e) extractive; f) residential. We also allow the presence of coastal and marine anthropogenic relief forms of other purposes in different regions of the sea coast. Separate geomorphological taxa are distinguished within elementary forms. It was found that within individual groups and types, they are divided into longitudinal and transverse, active and passive, large and small, vertical and horizontal, surface, underwater and complex, purposeful and accompanying, according to the material from which they are built, with natural relief and without him, ancient and modern. Some few taxa and elementary forms can be included in two or three complex forms and assignment groups, which leads to violations of the logical principles of classification construction. But such are the features of not only coastal and marine but also other classifications of anthropogenic relief. The given classification has a generally important theoretical and practical significance in geomorphology: it will contribute to further development of the general theory of anthropogenic geomorphology; will provide a characteristic of various anthropogenic forms necessary during the design and economic development of coasts; will be included in the educational program for the geographic disciplines “Geomorphology” and “Coastal science”, which will relieve geographer students of a false understanding of anthropogenic relief in the system of the coastal and marine environment.
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Skrzyński, Stanisław. "Research on Saturation Diving in Poland and its Implementation. Part I A. General Characteristics of Saturation Diving Research in Our Poland. Pioneer Times; 1967-1985." Polish Hyperbaric Research 77, no. 4 (2021): 53–72. http://dx.doi.org/10.2478/phr-2021-0021.
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Abstract The article is the first in a series of articles on the research and implementation of saturation diving technology in our country which presents the specific Polish conditions and achievements against the background of economic and historical circumstances. In view of the fact that research and implementation has a history of more than half a century, selected key figures of this period are recalled, some of whom have disappeared in the fogs of history. In the specialized literature of the world, the Polish underwater habitats of Meduza are among top 6 countries that researched and implemented, this high technology of saturation diving. Regarded as the inspirer, pioneer and creator of the first saturation diving, he designed and developed the technique and decompression with the cooperation of a team of enthusiasts from clubs and professional divers, as well as engineering staff from the Tri-City enterprises. In the first part of the article the author characterizes the saturation dives in comparison with short dives with particular emphasis on decompression, which is the key to safe diving. The article also takes into account the technical conditions for the implementation of the first saturation dives. The author discusses the general methodology of validation and verification of the assumed decompression, referring to the Polish conditions. He describes how the medical, technical, and organizational problems of implementation of saturation diving were solved in the pioneering period against the background of world achievements. Furthermore, the author describes Polish habitat constructions of Meduza and Geonur types and their application to underwater work on the Polish shelf and coastal areas. Despite the great progress in the field of medicine and technology, as well as organization, the problems of saturation diving, despite the passage of time, remain relevant, as these are the most difficult dives from the point of view of organization, underwater physiology and safety technology.
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Skrzyński, Stanisław. "Research on saturation diving in Poland and its implementation. Part I B. General characteristics of saturation diving research in our Poland. Pioneer times; 1967-1985." Polish Hyperbaric Research 75, no. 2 (2022): 73–86. http://dx.doi.org/10.2478/phr-2022-0005.
Full textAbstract:
Abstract The article is the first in a series of articles on the research and implementation of saturation diving technology in our country which presents the specific Polish conditions and achievements against the background of economic and historical circumstances. In view of the fact that research and implementation has a history of more than half a century, selected key figures of this period are recalled, some of whom have disappeared in the fogs of history. In the specialized literature of the world, the Polish underwater habitats of Meduza are among top 6 countries that researched and implemented, this high technology of saturation diving. Regarded as the inspirer, pioneer and creator of the first saturation diving, he designed and developed the technique and decompression with the cooperation of a team of enthusiasts from clubs and professional divers, as well as engineering staff from the Tri-City enterprises. In the first part of the article the author characterizes the saturation dives in comparison with short dives with particular emphasis on decompression, which is the key to safe diving. The article also takes into account the technical conditions for the implementation of the first saturation dives. The author discusses the general methodology of validation and verification of the assumed decompression, referring to the Polish conditions. He describes how the medical, technical, and organizational problems of implementation of saturation diving were solved in the pioneering period against the background of world achievements. Furthermore, the author describes Polish habitat constructions of Meduza and Geonur types and their application to underwater work on the Polish shelf and coastal areas. Despite the great progress in the field of medicine and technology, as well as organization, the problems of saturation diving, despite the passage of time, remain relevant, as these are the most difficult dives from the point of view of organization, underwater physiology and safety technology.
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Долгих, Г. И., and С. Г. Долгих. "Deformational features of tsunami." Гидросфера. Опасные процессы и явления 3, no. 2 (2020): 260–71. http://dx.doi.org/10.34753/hs.2020.2.3.260.
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Цунами являются одними из самых катастрофических природных явлений, приносящих колоссальные разрушения и уносящих большое число человеческих жизней. Причины возникновения цунами могут быть различными: подводные землетрясения, подводные оползни, извержения вулканов. Даже известны случаи возникновения цунами в результате обрушения в море больших оползней и обвалов. Изучением физики возникновения и развития цунами занимались с древности и продолжают заниматься учёные разных стран. Основное направление исследований связано с построением краткосрочного прогноза землетрясений. В настоящее время традиционные методы краткосрочного прогнозирования цунами основаны только на сейсмологической информации (магнитуде землетрясения, времени главного толчка и местоположении эпицентра). Магнитуда землетрясения, превышающая установленное пороговое значение, которое различается для разных цунамигенных зон, обычно приводит к выдаче предупреждения о цунами. Научная значимость и актуальность обозначенной проблемы очень высока, более того, она жизненно необходима для большинства населения планеты, живущего в прибрежных районах. Как показывает история последних десятилетий, особенно события 2004 и 2011 годов и последних лет, эффективность работы службы предупреждений о цунами далека от своего совершенства. Не предсказанные катастрофические цунами, плохая оценка энергии возникающих цунами, объявления ложных тревог приводят к большим экономическим и социальным потерям. Это связано, прежде всего, с отсутствием достоверного краткосрочного прогноза цунами. Работы последних лет, основанные на применении распределённой сети GPS-приёмников, системы DART, спутниковых технологий, направлены на решение данной проблемы, но итоговые результаты этих исследований пока не видны. Мы считаем, что решение задачи краткосрочного прогноза цунами, основанного на дистанционной регистрации деформационных процессов, происходящих в очаговой области места возникновения цунами, является самым перспективным направлением исследований. Tsunamis are one of the most catastrophic phenomena, causing tremendous destruction and claiming a significant number of lives. The causes of tsunamis can be different: water-quake, underwater landslides and volcanic eruptions. Even cases of tsunami are known as a result of the collapse of a huge mass of rocks in the sea. Scientists from different countries since antiquity have been studying the physics of the occurrence and development of tsunamis. The main direction of research is related to the construction of a short-term forecast of earthquakes. Currently, the traditional method of short-term tsunami forecasting is based only on seismological information (earthquake magnitude, main shock time and epicenter location). An earthquake magnitude exceeding a predetermined threshold value that differs between tsunamigenic zones usually results to a tsunami warning. The scientific significance and relevance of this problem is very high, moreover, it is vital for the majority of the world's population living in coastal regions. As the history of recent decades, especially the events of 2004 and 2011, and even recent years, shows, the efficiency of the tsunami service, to put it mildly, is far from perfect. The misses of catastrophic tsunamis, poor estimation of the energy of the arising tsunamis, false alarms, lead to very sad consequences. This is primarily due to the lack of a reliable short-term tsunami forecast. The works of recent years, based on the use of a distributed network of GPS receivers, DART systems, satellite technologies, are aimed at solving this problem, the final results of which are not yet visible. We believe that solving the problem of short-term tsunami forecast based on remote registration of deformational processes occurring in the source area of the tsunami origin is the most promising area of research, which will be partially confirmed in this paper.
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KUDRYASHOVA, Elena V., Mikhail Yu OPENKOV, and Larisa A. ZHGILEVA. "On the Methodology of Subglacial Oceans." Arctic and North, no. 43 (June 24, 2021): 253. http://dx.doi.org/10.37482/issn2221-2698.2021.43.253.
Full textAbstract:
Throughout all periods of development, the history of mankind has been closely intertwined with the sea. Craving for perception of the unknown has always been favored for humans. The interrelations between people and water element were actively considered by the representatives of natural, exact and engineering sciences. Humanitarian thought can also make a contribution to the study of the oceans. The authors propose substantiation for the formation of the methodology of subglacial oceans. The methodology refers to the theory of thought and action. Modern methodology is capable of constructing the ways of thinking that solve new issues and problems. Openness to criticism of methodological thinking is its strong and promising aspect. The study of the exploration techniques of the “second space”, starting with the first steps and up to the modern attempt to create an underwater prototype of the International Space Station, leads the authors to the conclusion about the possible equivalence of space and Arctic technologies. Exploration of the ice cosmic worlds of Pluto, Jupiter and Saturn may precede the study of the Arctic region. The Arctic has the potential to become a testing site for future space missions. The sterility of space technologies can, on the other hand, provide the development of the green economy in the Arctic.
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Krylov, Artem A., Daria D. Rukavishnikova, Mikhail A. Novikov, et al. "The Main Geohazards in the Russian Sector of the Arctic Ocean." Journal of Marine Science and Engineering 12, no. 12 (2024): 2209. https://doi.org/10.3390/jmse12122209.
Full textAbstract:
The Arctic region, including vast shelf zones, has enormous resource and transport potential and is currently key to Russia’s strategic development. This region is promising and attractive for the intensification of global economic activity. When developing this region, it is very important to avoid emergency situations that could result in numerous negative environmental and socio-economic consequences. Therefore, when designing and constructing critical infrastructure facilities in the Arctic, it is necessary to conduct high-quality studies of potential geohazards. This paper reviews and summarizes the scattered information on the main geohazards in the Russian sector of the Arctic Ocean, such as earthquakes, underwater landslides, tsunamis, and focused fluid discharges (gas seeps), and discusses patterns of their spatial distribution and possible relationships with the geodynamic setting of the Arctic region. The study revealed that the main patterns of the mutual distribution of the main geohazards of the Russian sector of the Arctic seas are determined by both the modern geodynamic situation in the region and the history of the geodynamic evolution of the Arctic, namely the formation of the spreading axis and deep-sea basins of the Arctic Ocean. The high probability of the influence of seismotectonic activity on the state of subsea permafrost and massive methane release is emphasized. This review contributes toward better understanding and progress in the zoning of seismic and other geological hazards in the vast Arctic seas of Russia.
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Brito, Cristina. "The Voice of Skogula in 'Beasts Royal' and a Story of the Tagus Estuary (Lisbon, Portugal) as Seen through a Whale's-Eye View." Humanities 8, no. 1 (2019): 47. https://doi.org/10.3390/h8010047.
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Patrick O’Brian inspired this work, with his 1934 book of chronicles “Beasts Royal,” where he gives a voice to animals. Therein, among other animals, we find Skogula, a young sperm whale journeying with his family group across the South Seas and his views on the surrounding world, both underwater and on land. This paper tells a story of historical natural events, from the viewpoint of a fin whale that travelled, rested and stranded in the Tagus estuary mouth (Lisbon, Portugal) during the early 16th century. It allows us to move across time and explore the past of this estuarine ecosystem. What kind of changes took place and how can literature and heritage contribute to understand peoples’ constructions of past environments, local maritime histories and memories? In the second part of this essay we present a fictional short story, supported on historical documental sources and imagery research where Lily, the whale, is the main character. Thus, we see the Tagus estuary as perceived through this whale’s-eye view. Finally, we discuss past earthquakes, whale strandings, the occurrence of seals and dolphins and peoples’ perceptions of the Tagus coastal environment across time. We expect to make a contribution to the field of the marine environmental humanities. We will do so both by addressing, by means of this literary approach, the writing of “new thalassographies,” oceanic historiographies and “historicities” and by including all intervening actors—people, animals and the physical space—in the understanding of the past of more-than-human aquatic worlds.
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Liu, Songyu, Taishan Lu, Guojun Cai, Kai Wu, Fengwen Lai, and Wenjun Xia. "Use of Cut-and-Cover method to Construct a 10-km Long Large-Span Underwater Tunnel: Case Study." Canadian Geotechnical Journal, February 19, 2025. https://doi.org/10.1139/cgj-2024-0400.
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This paper presents a comprehensive case study of the construction of a 10-km-long large-span underwater tunnel under Taihu Lake using the cut-and-cover method. The main challenges for the design and construction of the tunnel are limiting soil deformation and tunnel settlement, controlling the groundwater table, improving the construction efficiency, and meeting the environmental requirements. The strategies to address these challenges were summarized, including a four-zone staged excavation configuration, the use of piles for tunnel settlement control, and the use of cofferdams and waterproof curtains for groundwater control. The effectiveness of these strategies was validated by field observations, including deformations and stresses of cofferdams, retaining wall deflections, vertical and horizontal ground movements, groundwater table variations, and tunnel settlements. The observation results indicated that the measured values were smaller than the design limits, and no damage or leakage was observed during construction. This case history provides a valuable reference for the design and construction of similar tunnels.
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McCarthy, John, and Wendy van Duivenvoorde. "A Virtual Reconstruction of the Batavia Shipwreck in Its Landscape." Historical Archaeology, June 8, 2023. http://dx.doi.org/10.1007/s41636-023-00399-y.
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AbstractWe present a digital reconstruction of a shipwreck in a landscape context, illustrating the value of combining and synthesizing spatial data from a wide variety of sources to provide new insights on a heavily studied archaeological site. The shipwreck used for this case study is Batavia, one of the best-known shipwrecks in the world due to its rarity as an early Dutch East Indiaman, its association with the early days of the discipline of maritime archaeology, and with the dramatic events that followed the wrecking of the ship on an isolated reef off the west coast of Australia in 1629. The digital reconstruction of this shipwreck site leverages LiDAR, ship-construction manuals, and contemporary and modern ship models with underwater photogrammetry to provide new insights on the aftermath of the wrecking, site taphonomy on the seabed, and to recreate the visual aspects of the site.
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Zhao, Haonan, Xiaohua Zhao, and Hongyuan Fang. "Study on load distributing function of square slab surface under the action of underwater close‐in blast loading." Structural Concrete, February 13, 2024. http://dx.doi.org/10.1002/suco.202301027.
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AbstractThe mode and magnitude of the blast load are the main cause of damage to the structure. Most current studies have simplified the blast load into a bilinear form that differs greatly from the actual time history curve and is applied directly to the structure, avoiding the fluid–solid coupling interaction between the water fluid and the structure. The simplified blast load for near‐explosion or internal explosion will bring a big error to the calculation results. To quickly determine the load on the structure surface under the action of underwater near the explosion, this study studies the interaction between water hammer wave and structure through the verified full coupling model, and puts forward the explosion load distribution function on the square plate surface under the action of underwater explosion, and establishes a simplified prediction formula for the explosion load parameters (peak pressure and positive reflection impulse) at the center of the plate surface, using these formulas, a general method for constructing the explosion load at any point on the structural surface is proposed, which lays a foundation for subsequent structural damage and failure analysis.
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Barciela-Rial, Maria, Barend A. P. van den Bosch, Thijs van Kessel, Jasper Griffioen, and Johan C. Winterwerp. "Experimental and numerical analysis of underwater consolidation of dredged sediment: a case of study for the Marker Wadden." Frontiers in Marine Science 11 (December 2, 2024). https://doi.org/10.3389/fmars.2024.1466650.
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Dredged sediments, which are mud suspensions with concentrations exceeding the gelling point, are utilised in reclamation and Building with Nature projects. Beyond the gelling point, flocs occupy space and begin to form a network structure. This study investigates the impact of initial conditions, specifically the concentration above the gelling point and the stress state, on the consolidation of dredged sediment. The sediment from Lake Markermeer in the Netherlands was studied, specifically in the context of the construction of the Marker Wadden wetland. Material parameters were determined using two distinct experimental methods: settling columns and Seepage Induced Consolidation (SIC) tests. The differences observed between the two sets of material parameters suggest that the stress history and plastic deformation during mixing may influence the results. These effects were analysed using a one-dimensional vertical (1DV) consolidation model. The computed profiles were then compared with the profiles measured using an Ultrasonic High Concentration Meter. An initial concentration of 558.1 g/l, achieved by remixing the equilibrium profile of a normally consolidated suspension, resulted in larger final densities and a lower sediment-water interface. Conversely, a concentration of 175.6 g/l, achieved by remixing consolidating dredged sediment, yielded the same equilibrium layer thickness and density profile as virgin consolidation, albeit after a longer consolidation time. These findings are particularly relevant for land reclamation and wetland construction projects, where the initial density may be high and the dredging process’s mixing may alter the stress state.
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Jilkén, Olle. "A Mythological Nudist Lost in Swedish Suburbia: A study of the Nix’s masculinity and media-loric function in the manga series Oblivion High." Shima: The International Journal of Research into Island Cultures 15, no. 2 (2021). http://dx.doi.org/10.21463/shima.134.
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This article explores the visual representation and function of the folkloric Scandinavian nix in the manga series Oblivion High (2012–2014) published by the manga studio Ms Mandu. The aim of the research is to investigate how a well-known folkloric image develops and to consider the nix’s portrayal of masculinity. The article is a critical cultural study based on feminist and queer perspectives on visual culture and folklore studies. The article concludes that the nix in Oblivion High must update his desirability through spectacular clothing and change of musical instrument to meet the contemporary Western heteronormative masculinity ideals. His weakness to the metal iron ties into the nix’s association to fairies and the construction of the nix’s underwater realm is connected to Norse mythology with the appearance of Aino from the Finish national epos Kalevala, Nornorna and hints of the Norse god Odin. Furthermore, the androgynous art style of shōjo manga (a sub-genre aimed at female teenage readers) creates a heterosexual female gaze pattern, while the imagery of a bishōnen (beautiful boy) connects the character Nix to the literary trope of the ‘pretty boy,’ leaving hegemonic masculinity unchallenged.
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Q, Ma, Wu D, Yue Y, et al. "The Effect of 6-Meter Underwater Diving Intervention on Recovery of Exercise-Induced Fatigue." Austin Sports Medicine 8, no. 1 (2023). http://dx.doi.org/10.26420/austinsportsmed.2023.1055.
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Objective: To evaluate the effect of 6-meter underwater diving on recovery of exercise-induced fatigue and explore the potential mechanism. Method: Thirty-three male sophomores majored in physical education were included in this self-control, cross-over study. The fatigue was induced through programed swimming exercise at same intensity for both control and intervention groups. After exercise-induced fatigue, the subjects recovered through sitting on the floor and 6-meter underwater diving for 15 minutes in control and intervention groups respectively. The parameters observed included Heart Rate (HR), Critical Flicker Frequency (CFF), Simple Reaction Time (SRT) and Standing Long Jump (SLJ). Results: The HR was faster after exercise and recovery compared to that before exercise in both groups. SLJ was shorter after recovery compared to before exercise fatigue in both groups. After diving recovery, the CFF was lower than that before exercise fatigue, while the index of SRT was higher than that before exercise fatigue. Compared with the control group, the HR and SRT were significantly lower, but the SLJ and CFF were significantly higher in the intervention group than those of control group (HR, p<0.05; SRT, p<0.01, SLJ, CFF p<0.01). Conclusion: The fatigue recovery effect of 6m underwater environment is better than that of land recovery. The low temperature, mild hyperbaric oxygen, water pressure and buoyancy in under water environment may promote the repair of muscle and motor nerve after exercise and improve the exercise performance after intervention.
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Lebedev, P. D., A. A. Lempert, and A. L. Kazakov. "Algorithms of optimal covering of 2D sets with dynamical metrics." Izvestiya Instituta Matematiki i Informatiki Udmurtskogo Gosudarstvennogo Universiteta, November 2022, 58–72. http://dx.doi.org/10.35634/2226-3594-2022-60-04.
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The paper deals with the problem of constructing the thinnest covering for a convex set by a set of similar elements. As a distance between two points, we use the shortest time it takes to achieve one point from another, and the boundary of each covering circle is an isochron. Such problems arise in applications, particularly in sonar and underwater surveillance systems. To solve the problems of covering with such circles and balls, we previously proposed algorithms based both on variational principles and geometric methods. The purpose of this article is to construct coverings when the characteristics of the medium change over time. We propose a computational algorithm based on the theory of wave fronts and prove the statement about its properties. Illustrative calculations are performed.
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Alshehri, Ali, Lujain K. Bukhari, Shatha A. Almasswary, et al. "Prevalence of Eustachian Tube Dysfunction and Its Associated Factors among the General Public in Aseer Region, Saudi Arabia." World Family Medicine Journal /Middle East Journal of Family Medicine, January 2024. http://dx.doi.org/10.5742/mewfm.2024.95257003.
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Introduction: The Eustachian tube connects the middle ear to the back of the nose. When it doesn’t function properly, it’s called Eustachian Tube Dysfunction (ETD). This can lead to symptoms like muffled hearing, popping sounds, and discomfort. Recent studies in Saudi Arabia found high ETD prevalence rates (around 42.49%). ETD can cause ear issues and impact daily life. This study aims to evaluate the prevalence and associated factors of ETD in the Aseer region, Saudi Arabia. Methodology: A descriptive cross-sectional questionnaire-based study was conducted among the population of Aseer region in Saudi Arabia. Data was collected through an online self-administered questionnaire (ETDQ-7). Data was analyzed using SPSS. Results: Only 4% of participants had a history of Eustachian tube dysfunction. Hearing loss was reported by 27.3%, with 23.3% having a family history of it. Gender-wise, 31.86% of females and 17.71% of males had a history of hearing loss, the difference being statistically significant (p=0.007). Smoking exhibited a strong correlation, with 60.98% of smokers and 22.01% of non-smokers reporting hearing loss, the difference being highly significant (p=0.0001). Ear-related issues were prevalent, such as severe pain (41%), underwater sensation (36%), and cold-related problems (23%). Additionally, symptoms like cracking sounds (12%), ringing (16%), and muffled hearing (22%) were noted, sometimes affecting both ears (29%). Conclusion: A significant association was found between smoking and hearing loss. Gender and smoking habits showed significant correlations with hearing loss. The low prevalence of ETD warrants further investigation. These findings contribute to the existing body of knowledge on auditory health and could inform targeted interventions for hearing-related issues in the region. Keywords: Eustachian Tube, Dysfunction, Prevalence, Risk factors, population, Saudi Arabia
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Asmiani, Asmiani, and Hayari Hayari. "SEJARAH BANDARA MATAHORA DI PULAU WANGI-WANGI KABUPATEN WAKATOBI (2007-2017)." Jurnal Penelitian Pendidikan Sejarah UHO 3, no. 3 (2020). http://dx.doi.org/10.36709/jpps.v3i3.12820.
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ABSTRAK: Permasalahan pokok dalam penelitian ini adalah: (1) Apa latar belakang pembangunan Bandara Matahora di Pulau Wangi-Wangi Kabupaten Wakatobi, (2) Apa kendala yang dihadapi dalam pembangunan Bandara Matahora di Pulau Wangi-Wangi Kabupaten Wakatobi? (3) Apa dampak yang ditimbulkan terhadap pembangunan Bandara Matahora di Pulau Wangi-Wangi Kabupaten Wakatobi? dan (4) Bagaimana Perkembangan pembangunan Bandara Matahora di Pulau Wangi-Wangi Kabupaten Wakatobi? Penelitian ini menggunakan metode sejarah yang dikemukakan oleh Helius Sjamsuddin, yang terdiri atas 3 tahap yaitu: (1) Heuristik yakni mencari sumber melalui wawancara, studi kepustakaan, dan penelitian lapangan, (2) Kritik Sumber terdiri atas kritik eksternal dan kritik internal guna mendapat data yang akurat, (3) Historiografi yang dimaksudkan dalam bentuk karya tulis kronologis, sistematis dan ilmiah. Penelitian ini menunjukan bahwa latar belakang perkembangan Bandara Matahora berawal dari pemikiran atau ide bupati wakatobi Ir. Hugua yang yang tergambar dalam visi misinya membangun dan menjadikan Kabupaten Wakatobi menjadi daerah yang digemari oleh banyak orang dengan visi “Terwujudnya Surga Nyta Bawah Laut di Pusat Segitiga Karang Dunia” (2) Kendala yang dihadapi dalam pembangunan Bandara Matahora dapat dilihat dari pandangan masyarakat yang diwujudkan dalam bentuk respon dari masyarakat berkaitan dengan pembangunan Bandara Matahora serta kecenderungan rencana yang dilakukan pasca Bandara terbangun. Respon yang dimaksud adalah respon mengenai pembangunan Bandara Matahora. Misalnya dari satu pihak menerima adanya Bandara Matahora dipihak lain ada yang menolak pembangunan Bandara Matahora. (3) Dampak dari pembangunan Bandara Matahora ialah terdapat dampak yang bersifat positif dan yang bersifat negatif bagi masyarakat dan daerah. (4) Perkembangan pembangunan Bandara Matahora dari tahun ke tahun semakin bagus, dimana Bandara yang menjadi kebanggaan masyarakat tersebut digunakan dengan semaksimal mungkin dan pembangunan tambahan Bandara terus berkelanjutan hingga saat ini. Disamping itu, banyak wisatawan dalam dan luar negeri yang menggunakan Bandara Matahora tersebut sebagai alternatif yang memungkinkan perjalanan masyarakat bisa dijangkau dengan cepat. Kata Kunci: Sejarah, Bandara Matahora, Pulau Wangi-Wangi, dan Wakatobi ABSTRACT: The main problems in this study are: (1) What is the background of the development of Matahora Airport on Wangi-Wangi Island, Wakatobi Regency, (2) What are the obstacles faced in the construction of Matahora Airport on Wangi-Wangi Island, Wakatobi Regency? (3) What are the impacts on the construction of Matahora Airport on Wangi-Wangi Island, Wakatobi Regency? and (4) How is the development of Matahora Airport development on Wangi-Wangi Island, Wakatobi Regency? This research uses the historical method proposed by Helius Sjamsuddin, which consists of 3 stages, namely: (1) Heuristics which is looking for sources through interviews, library research, and field research, (2) Source Criticism consists of external criticism and internal criticism in order to obtain data accurate, (3) Historiography intended in the form of chronological, systematic and scientific writing. This research shows that the background of the development of Matahora Airport originated from the thoughts or ideas of the Regent of Wakatobi, Ir. Hugua, who is depicted in his vision and mission to build and make Wakatobi Regency a favorite area for many people with the vision of "Realizing the Underwater Paradise of the Sea at the Center of the World Coral Triangle" (2) Constraints faced in the construction of Matahora Airport can be seen from the view of the community that is realized in the form of response from the public relating to the construction of Matahora Airport and the tendency of plans to be carried out after the Airport was built. The response in question is the response regarding the construction of Matahora Airport. For example, from one party accepting the existence of Matahora Airport, on the other hand there are those who reject the construction of Matahora Airport. (3) The impact of Matahora Airport development is that there are positive and negative impacts on the community and the region. (4) The development of the Matahora Airport development from year to year is getting better, where the Airport which is the pride of the community is used to the maximum extent possible and the construction of additional airports continues to the present. In addition, many domestic and foreign tourists who use the Matahora Airport as an alternative that allows people's trips can be reached quickly. Keywords: History, Matahora Airport, Wangi-Wangi Island, and Wakatobi
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Perez-Alvaro, Elena. "Indigenous rights and underwater cultural heritage: (de)constructing international conventions." Maritime Studies 22, no. 3 (2023). http://dx.doi.org/10.1007/s40152-023-00320-6.
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AbstractPeople, ideas and products of all civilisations have been moved by ships, making oceans one of the major drivers for the divergence and convergence of human societies. Furthermore, human beings have interacted and lived on and around oceans, so their heritage provides testimony to many periods and aspects of our shared history. The marine policies to protect underwater and coastal heritage are complex, since this heritage has an intricate two-way relationship with anthropology and law. The legal instruments to specifically protect underwater cultural heritage do not include the consideration of Indigenous communities, although there are nearly 2000 coastal Indigenous communities in 87 countries with coastal heritage and maritime-based traditions. Since it is the law of Coastal States (emphasis on States) that directs how submerged lands and waters that belonged to Indigenous communities are used, the international legal instruments offer little actual leverage to these communities over the management of their cultural resources. This article studies Indigenous rights over their underwater cultural heritage, exploring the legal issues, anthropological arguments and ethical dilemmas. It will also show the complexity of the language and the interpretation of international treaties for these communities. Finally, the article encourages inclusion of the Indigenous concept of intangible cultural heritage, arguing that Indigenous peoples have been, and are, innovative users of natural resources, and their traditional activities can benefit not only their own members but also the international community.
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Pinghao, Zhang, Jiang Gang, and Hu Yanhong. "Budget and Management Inspiration for the Research and Development Expenses of the US Navy's Unmanned Underwater Vehicle." Science Innovation, November 29, 2023. http://dx.doi.org/10.11648/j.si.20231106.19.
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Qin, Ke, Li He, Ding Chaolong, et al. "Favorable Reservoir Formation Models for Nearshore Underwater Fans in Narrow and Long Graben Type Fault Basins: A Case from Botai Sag of Yitong Basin." Earth Sciences, January 18, 2024. http://dx.doi.org/10.11648/j.earth.20241301.11.
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Wahlig, Victoria, and Ricardo A. Gonzales. "Enhancing marine debris identification with convolutional neural networks." Journal of Emerging Investigators, 2024. http://dx.doi.org/10.59720/23-150.
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Oceanic debris, predominantly plastic, inflicts catastrophic damage on marine ecosystems, threatens aquatic life through entanglement, strangulation, and starvation, and increasingly accumulates as microplastics within the tissues of marine species consumed by humans. Assessing and mitigating this crisis is complicated by the wide-ranging distribution of waste by ocean currents to remote and deep-sea locations. In this study, we developed a deep learning model to discern and identify components of images captured by an underwater remotely operated vehicle (ROV). We hypothesized that the model would achieve an 80% accuracy. We utilized image segmentation, a process that groups or "masks" all pixels associated with a specific object in the image, to recognize and delineate image components (trash, animal, plant, ROV). We trained our model using the established TrashCan 1.0 dataset, which comprises images captured by ROVs in the Sea of Japan. Our model, a convolutional neural network employing U-Net architecture, formulated feature maps for each object within the images, enabling prediction of object classes. During the testing phase, we compared the model-generated object masks against reference masks to establish the Dice Similarity Coefficient (DSC) for each object class (trash = 0.81 ± 0.38, animal = 0.85 ± 0.35, plant = 0.88 ± 0.31, ROV = 0.86 ± 0.29, overall average = 0.84 ± 0.36). The consistent categorization of image components by our model demonstrates its potential as an effective ROV-borne tool capable of identifying and targeting hitherto inaccessible ocean trash. Our study lays a robust foundation for future research and additional applications.
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"Review of Carvel Construction Technique—5th International Symposium on Boat and Ship Archaeology, Amsterdam, 1988, by R. Reinders and K. Paul; Anatomy of the Ship, the 24-gun Frigate Pandora, by J. Mackay and R. Coleman; The Prehistoric Exploration and Colonization of the Pacific, by G. Irwin; La Charpenterie Navale Romaine, by M. Rival; Advances in Underwater Archaeology, by J. B. Arnold III; Kultschiffe und Schiffskulte im Altertum, by A. Göttlicher and Eighteenth Century Shipbuilding: Remarks on the Navies of the English and the Dutch, by B. Ollivier." International Journal of Nautical Archaeology 22, no. 3 (1993): 299–304. http://dx.doi.org/10.1006/ijna.1993.1016.
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