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Ports are one of the structures where the effects of global warming are most severe and intense in atmospheric, oceanic, and geographical terms. According to the Intergovernmental Panel on Climate Change (IPCC)'s assessment reports, although it is possible to slow down global warming by reducing greenhouse gas (GHG) emissions, it is not foreseen to stop global warming and sea level rise (SLR) in any scenario. The rising sea level, an inevitable consequence of global warming, is a clear threat to conventional port facilities. In summary, SLR triggered by climate change, which is today's hot topic, may cause conventional port infrastructures to be flooded and lose their functionality. To cope with this threat, port facility planning, and design stages must be carried out by referring to the updated threshold values in Shared Socioeconomic Pathway (SSP) scenarios defined by the Working Groups of the IPCC. However, the uncertainty about the scale, timing, and location of SLR makes definitive solution-oriented approaches more prominent. One of these approaches is floating port structures. This study aims to reveal the role of floating port structures in the implementation of the relocation measure emphasized in the IPCC Sixth Assessment Report (AR6) for conventional ports under the threat of SLR. Initially, in this study, regions with higher SLR risk were identified by considering SSP scenarios contributed by Sixth Phase of the Coupled Model Intercomparison Project (CMIP6) data. Afterwards, the dynamic downscaling model was used to determine the regions with higher regional sea level rise (RSLR) risk and the Marine Traffic database was used to determine the ports in these regions. Thus, it is evaluated whether floating ports can be a suitable alternative in the relocation decision of ports under SLR risk. It is expected that maritime transport will be maintained at adequate security and operational levels by revealing the pros and cons of floating ports. [ABSTRACT FROM AUTHOR]

Abstract In the processes of lowering down or raising up the legs of a floating structure, the legs are neither touch with the sea bed nor completely lift up, and the structure is situated in the condition of freely floating on the waves. The existing of the legs equipped on the structure leads to the property different hydroelastic responses from the ordinary floating structures. To investigate the variation of the length of the legs underwater affecting the hydroelastic responses, a plate-cell model is proposed, and the basin tests using the elastic model in waves are carried out. Based on the length of the legs under water, the model is set as 2 cases. The attenuation tests in calm water and test in the regular wave at zero speed in various of the wave conditions are carried out. According to the plate-cell model, a numerical model is constructed to simulate the hydroelastic responses of the 2 cases based on the theory of the three-dimensional (3-D) linear hydroelasticity. Both the experimental and numerical results demonstrate that the legs have significant influences on the hydroelastic responses of the structure. Highlights • A new hydroelastic experimental method is introduced for researches on floating structure with legs. • The significant influences of the length of underwater legs are investigated by experimental and numerical simulations. • Not only the conclusions of this paper, but also the experimental methods introduced in this paper have valuable references to relevant researches. [ABSTRACT FROM AUTHOR]

This study reports a multi-scale structural analyses of a mainline floating double carcass marine hose (nominal diameter 508 mm, length 10.7 m, design pressure 2.1 MPa, weight 4100 kg). A material change in the reinforcement cords of the traditional hose is proposed, from polyester and polyamide to hybrid aramid/polyamide cords, allowing an improvement in design, reducing weight and increasing flexibility. Two models have been developed to obtain the hose responses. Firstly, a finite element model of the traditional system was built to perform a macro-scale analysis of global hydrodynamics loads in the hose line using Orcaflex™ software. Then, a non-linear finite element model was developed for meso-scale analysis using Abaqus™ software. Rubber and cords were modeled using hyperelastic models, and axial, bending and torsional stiffnesses were evaluated. Experimental tests were carried out to assess the mechanical response of an actual full-scale hose. The reduced number of layers of the hose using hybrid cords, compared to the traditional one, allowed a reduction in weight of 15%, and brought also a decrease in specific axial, torsional and bending stiffnesses of 43.9%, 52.2% and 21.6%, respectively. The multi-scale analysis predicted well the structural response of the hose line, and the reduced potential failure may increase life-time of the structure. [ABSTRACT FROM AUTHOR]

The model test method of the FPSO and offloading system is investigated by using the development mode of “FPSO + CALM + TANKER” working in a 1700-m depth of offshore West Africa. An equivalent design based on static and dynamic similarity criteria for oil offloading line (OOL) is discussed, and a type of creative method for the equivalent design of OOL in a model test is proposed. Based on the static similarity criterion, the truncated design of the FPSO mooring system in water depth and horizontal directions is carried out. After that, a relevant static optimization is conducted. Meanwhile, to avoid interference between the FPSO mooring system and CALM mooring system, a horizontal equivalent design for the CALM mooring system is provided. On this basis, the model test scheme is conducted. Time domain coupled analyses for the whole system before and after truncation are later performed. After comparison, it is observed that the calculated results of the truncated system are basically consistent with those of the prototype system, and the design of the model test scheme is demonstrated to be robust and reliable. [ABSTRACT FROM AUTHOR]

Marine constructions modify physical conditions by interfering with water circulation and increasing sedimentation and pollution, leading to biological homogenization. However, they also increase the availability of hard substrata for larval recruitment, resulting in the development of a diverse sessile community and associated fish fauna. To describe how the modifications caused by a floating marina affect reef fish assemblages at São Sebastião Channel, SW Atlantic, a multiparameter probe and a visual census methodology were used to compare the abiotic conditions and the diversity and abundance of fishes between two areas: the area inside the marina where boats are moored and the breakwater, an area more similar to nearby natural rocky shores. The area inside the marina presented more turbid and productive waters, while the breakwater was more turbulent. The abundance of fishes inside the marina was greater than at the breakwater throughout the study, but species richness was higher inside the marina only during the hot and wet period (Austral Summer and Spring). Fish assemblages were strictly different between areas. Species dominance for each area and at nearby natural rocky reefs was also different. This study shows that artificial habitat causes micro-spatial modifications to local fish assemblages. As spatial variations were related to the behavioural and ecological aspects of fishes, marine facilities should be carefully planned, and engineering principles should be combined with ecological processes to better resemble natural habitats, thereby reducing environmental impacts. [ABSTRACT FROM AUTHOR]

A semi-floater concept as a substructure for multi-megawatt wind turbines is developed herein for installation at 50+ m water depths. The semi-floater concept is a hybrid between a fixed monopile type support structure and a floating spar buoy. The configuration of the substructure is composed of a floating system, a mooring system, and an articulated joint. A case study is carried out under specific design conditions and constraints. The detailed designs of the mooring system and of the articulated joint are iteratively carried out using a hydro-servo-elastic analysis tool for structure response, HAWC2, coupled with dedicated in-house software packages for structural design analysis, and Abaqus. A reliability analysis and fatigue load calculations are made to ensure a desired life expectancy of the structure. The semi-floater concept is shown to maintain acceptable fatigue load levels for all turbine components, and to exhibit low platform displacement at the mean sea level. Finally, the overall performance of the structure related to energy production is similar to that of a reference wind turbine situated on land. [ABSTRACT FROM AUTHOR]

This study presents data on abundance and density of macro-floating marine debris (FMD), including their composition, spatial distribution and potential sources off continental Portugal. FMD were assessed by shipboard visual surveys covering ± 252,833 km 2 until the 220 nm limit. The FMD average density was 2.98 items/km 2 and abundance amounted to 752,740 items. Unidentified plastics constitute the major bulk of FMD (density = 0.46 items/km 2 ; abundance = 117,390 items), followed by styrofoam, derelict or lost materials from fisheries, paper/cardboard and wood material. The North sector of the area presents higher FMD diversity and abundances, probably as a result of the high number of navigation corridors and fisheries operating in that sector. Most FMD originate from local sources, namely discharges from vessels and derelict material from fisheries. Considering the identifiable items, cables and fishing lines were the only fishing related items among the top ten FMD items in Portuguese offshore waters. [ABSTRACT FROM AUTHOR]

Knowledge of biofouling typical of marine structures is essential for engineers to define appropriate loading criteria in addition to informing other stakeholders about the ecological implications of creating novel artificial environments. There is a lack of information regarding biofouling community composition (including weight and density characteristics) on floating structures associated with future marine renewable energy generation technologies. A network of navigation buoys were identified across a range of geographical areas, environmental conditions (tidal flow speed, temperature and salinity), and deployment durations suitable for future developments. Despite the perceived importance of environmental and temporal factors, geographical location explained the greatest proportion of the observed variation in community composition, emphasising the importance of considering geography when assessing the impact of biofouling on device functioning and associated ecology. The principal taxa associated with variation in biofouling community composition were mussels (Mytilus edulis), which were also important when determining loading criteria. [ABSTRACT FROM AUTHOR]

Marine litter is one of the descriptors in the European Marine Strategy Framework Directive, which aims to achieve a healthy marine environment and make ecosystems more resilient to climate change. Most experiences have been focused upon quantifying the abundance and distribution of marine litter, on beaches in particular. Nevertheless, the continuous impact of litter on marine species, commercial activities, i.e. shipping and fishing, and the local economy are prompting scientist and stakeholders to identify additional approaches required to face this challenge. This contribution addresses the aforementioned need, by assessing the possibility of fishing vessels shifting from fish to floating marine litter (FML), during low fishing activity periods. For this purpose, the technical, environmental, and socio-economic feasibility of such a change is investigated. The technical assessment includes: the analysis of energy consumption; and the assessment of ocean surface current patterns as a tool to determine FML convergence hotspots. The environmental feasibility is analysed by a Life Cycle Assessment study of 3 FML management scenarios. The minimum subsidy required is analysed in the socio-economic assessment, in order to reach a profitable diversified activity. The results demonstrate fishing FML as a technically-, economically- and environmentally-viable activity. Nevertheless, Local Authorities need to encourage the prevention of FML arriving on shore where, in some environments, such as in rocky shores, cleaning is difficult. [ABSTRACT FROM AUTHOR]

Xu, S.; Zhu, J.; Gao, Q., and Zhu, B., 2015. Sailing routes designing: based on ILNS-CMAHLP. Sailing routes is the basis of carrier's survival, the planning of route network is the strategic for the carrier. Optimization theory of hub and spoke network is a highly simplified result in specific constraints of the network composed by the given nodes, so the theory plays little roll in the actual network planning. According to the complex network theory, we establish the route network design model with the constraints of investment limit, non-strict, capacitated and multiple allocation, the aim of model is to minimum the total cost of the route opened cost, the transportation cost, the hub node construction cost, the opportunity cost caused by the not yet been transported; secondly, to study the ILNS-CMAHLP problem based on the Mixed Set Programming (MSP) theory, we make the data model with the set variables, give the logic model to express the relation among input variables, output variables and decision variables, build the solve rule based on the set reasoning algorithm. Finally, we calculate the ILNS-CMAHLP exact solution of NCL language in the POEM optimization platform. Results show that the NCL algorithm, which has the natural modeling and mixed set programming features, is a useful tool to solute the constraints of joint solving of NP-Hard problem, and it will avoid the combination explosion problem of large-scale integer programming; at the same time, it will open the new research direction for the optimization of hub and spoke network with the capacitated etc. constraints, it can provide theoretical guidance and technical support for the actual route network planning. [ABSTRACT FROM AUTHOR]

In this work is developed method of evaluation safety level, which decreases with floating intensity functioning during technical object. Factors, condition such changes were reviewed. Basing on proposed methodic of detection of various types of risks exists possibility to form constructive algorithms of evaluation of safety level, which allows forming adequate danger counteraction means. One of basic factors, representing dangers, is malfunctions, appearing on technical object. [ABSTRACT FROM AUTHOR]

Summary Background Repair of DNA double-strand breaks (DSBs) by homologous recombination requires 5′-3′ resection of the DSB ends. In vertebrates, DSB resection is initiated by the collaborative action of CtIP and the MRE11-RAD50-NBS1 (MRN) complex. However, how this process occurs within the context of chromatin is still not well understood. Results Here we identify the human SRCAP chromatin remodeling complex as a factor that promotes CtIP-dependent DNA-end resection. We show that SRCAP, which is mutated in Floating-Harbor syndrome, confers resistance to DNA damage-inducing agents and is recruited to DSBs. Moreover, we demonstrate that SRCAP is required for DNA-end resection, and thereby for recruitment of RPA and RAD51 to DSBs, and for the ensuing homologous recombination. Finally, we reveal that SRCAP forms a complex with CtIP and promotes accumulation of CtIP at DSBs through a mechanism involving its ATPase activity. Conclusions Our study implicates the human SRCAP chromatin remodeling complex as a novel regulator of DNA damage responses that orchestrates proper signaling and repair of DSBs in the context of chromatin. [ABSTRACT FROM AUTHOR]

The article discusses the operations and maintenance of floating production storage and offloading (FPSO) installations. Topics covered include the number of FPSO operating worldwide, the capacity of Korea and Japan to build large crude carriers, and the advantages of the conversion option. Also mentioned are the challenges in the integrity management of the typical FPSO, designing FPSO, and the regulations in the International Convention for the Safety of Life at Sea (SOLAS).

The article discusses the different challenges, trends and advances in offshore deep water development. Topics covered include the importance of obtaining access to enough exploitable reserves, the extremely high capital cost of entering the deep water contracting market, and the production sharing agreements (PSA)in many developing countries. Also mentioned are risers as the most costly elements in deep water developments, helicopter operations safety, and life extension of floating systems.

Abstract: This paper presents a preliminary technical and economic evaluation for a new concept, the Floating Container Storage & Transhipment Terminal, or ‘FCSTT’. The main purpose of the FCSTT is considered to handle transhipment traffic, although its use could extend to supporting existing land-based terminals within ports. The paper considers a range of floating port structures already in operation, and other concepts yet to be developed. To an extent the FCSTT, which is based on conversion of a large container vessel, is an extension of these and other developments in different shipping sectors. The FCSTT can handle container cargo in offshore locations and/or wherever there is a need to provide ‘terminal’ infrastructure rapidly and at low cost. Our approach outlines design options for a FCSTT including analysis of crane preferences. The paper includes analysis of required storage capacity, and container handling productivity levels sufficient to ensure a practical terminal that is comparable with any landside facility, albeit with a focus on transhipment traffic. Thereafter the capital and operating costs for the FCSTT are estimated, with forecast cash flows based on assumed traffic volumes and competitive handling rates. Conclusions suggest the FCSTT offers potential for significant capital and operating cost savings compared to higher cost landside terminal infrastructure. Other key factors and advantages, including areas for further research, are highlighted. [Copyright &y& Elsevier]

The VLFS (Very Large Floating Structures) are the floating structures that respond to the needs of real state development at sea, mainly for the creation of floating harbors and airports, both in the coast and in the open ocean. Due to the greater space requirements than in the nowadays floating structures (pontoons, barges, ships, offshore platforms) it is still a technology in experimental stage. Several designs have been proposed, according to the depth and the proximity to the coast. The increase in costs of real state at land and in the sensibility for the protection of the coastal areas, will have a main impact in the development of these structures in the XXI century. [ABSTRACT FROM AUTHOR]

In this research, a typical tension-leg type of floating platform incorporated with an innovative concept of underwater tuned liquid column damper system (UWTLCD) is studied. The purpose of this study is to improve the structural safety by means of mitigating the wave induced vibrations and stresses on the offshore floating Tension Leg Platform (TLP) system. Based on some encouraging results from a previous study, where a Tuned Liquid Column Damper (TLCD) system was employed in a floating platform system to reduce the vibration of the main structure, in this study, the traditional TLCD system was modified and tested. Firstly, the orifice-tube was replaced with a smaller horizontal tube and secondly, the TLCD system was combined into the pontoon system under the platform. The modification creates a multipurpose pontoon system associated with vibration mitigation function. On the other hand, the UWTLCD that is installed underwater instead would not occupy any additional space on the platform and yet provide buoyancy to the system. Experimental tests were performed for the mitigation effect and parameters besides the wave conditions, such as pontoon draught and liquid-length in the TLCD were taken into account in the test. It is found that the accurately tuned UWTLCD system could effectively reduce the dynamic response of the offshore platform system in terms of both the vibration amplitude and tensile forces measured in the mooring tethers. [ABSTRACT FROM AUTHOR]

This paper describes the preliminary design of a floating support structure for offshore wind turbines that has been developed by ERSE (former CESI RICERCA). It considered the prospects that this kind of structure could hold for exploiting wind resources in the windiest sea areas along the coasts of Italy (Sardinia, Sicily, Apulia). A review of the various types of floating structure that have been devised worldwide for wind turbines has made it possible to single out the floating structure that looks most interesting from the technical and economic standpoint. Specifically, the selected structure is of the Tension Leg Platform (TLP) type. It consists of a nearly fully submerged hexagonal platform, which carries a 6 MW wind turbine and is linked to the sea bottom by 6 ties, which assure stability and limited tilting, even under the worst loads induced by wind and sea. The construction and installation phases for this structure have been analysed, and the most effective and economically viable techniques chosen. With a view for avoiding the use of expensive sea craft, the floating structure has been designed in such a way that it can be towed to its site with the wind turbine already standing on it. A preliminary dimensioning of the floating structure has been carried out, along with technical verification of the main structural members. This work has been performed in cooperation with the engineering company TECON, which used, among others, the MOSES computation code by Ultramarine. Attention has also been devoted to the most suitable options for mooring the floating structure to the sea bottom. To assess the behaviour of the floating system under the action of wind and waves, the computational code (BM) has been developed by ERSE. This code takes into account the whole "wind turbine + floating platform" system, represented by a scheme featuring 8 degrees of freedom. Using this code no anomalous or unexpected behaviours were observed. The costs of building and installing this floating system have been calculated, drawing on experience gained with similar offshore structures in the oil and gas fields. The unique conditions of Italy as regards shipyards, harbours, electrical grid layout etc. have been taken into account. Along with estimates of operation and maintenance costs, and annual energy yields, these results have allowed the calculation of the probable unit energy production costs of floating wind farms in deep-water coastal areas of Italy. [ABSTRACT FROM AUTHOR]

In principle, appropriately designed floating support structures need not be more massive nor costly than the jackets or tripods being deployed in German North Sea waters and elsewhere. A number of significant challenges remain, not least the current limited operating experience but also the limited availability of comprehensive design and modelling capabilities, and demonstrated and widely applicable safe and cost-effectively installation methods. This paper assesses the prospects in terms of technology principles, challenges and the potential resource. [ABSTRACT FROM AUTHOR]

Purpose - A close dry port with direct rail connection to a seaport is a potential solution for seaport terminal congestion as well as for better seaport inland access. The purpose of this paper is to investigate and define impediments to a close advanced intermodal terminal - dry port implementation. Design/methodology/approach - Comparative case studies through face-to-face interviews and a literature review have been carried out in order to accomplish the purpose. In addition, secondary sources such as reports, internal documents and web pages were used. Findings - The most common factors that impede dry port implementation are infrastructure, land use, environment and regulations. Hence, the same reduce the efficiency of freight movements on land access routes to and from seaports. An advanced intermodal terminal must fit into a complex system where the necessary infrastructure is in place and the regulatory systems are properly designed to optimize the involvement of both the public and the private sector. Research limitations/implications - Empirical data for the case studies are collected at Port Botany, Sydney, and its close intermodal terminals. A more comprehensive view of the problem could be obtained through additional case studies on other countries' seaports' intermodal terminals. Originality/value - The idea behind the study is to contribute to a better understanding of the concept of close dry port through the factors that influence the implementation of the same and thereby to improve knowledge of the implementation of the concept. [ABSTRACT FROM AUTHOR]

Abstract: Steep wave impact pressures and the structural dynamic response of floating production storage and offloading platform (FPSO) bows are studied using 1:80 scale segmented, instrumented models. The construction of these segmented models is discussed. The ‘new-wave’ theory is adopted and extended to generate steep waves and a limiting form of steep wave that might be found in deep water is proposed. A comparison between linear theoretical, experimental and suggested wave models is made. Experimental results with systemically varying parameters are presented. [Copyright &y& Elsevier]

Abstract  A technique of determining the time when drilling operation must be halted on the basis of the predicted control of the movement of floating marine platforms is proposed. By means of the technique it becomes possible to adopt with a high degree of reliability a correct decision as to whether to continue or to halt drilling when the platform is functioning under conditions of random wind and wave disturbances. [ABSTRACT FROM AUTHOR]

This paper highlights an experimental investigation on the dynamic response of a typical floating, production, storage, and offloading system (FPSO) moored externally with a fixed structure and by a vertical anchor leg mooring arrangement. A 1:100 scale model of 140,000 t DWT FPSO system was tested for these two types of mooring arrangements under regular waves for three operating conditions, i.e., 40, 70, and 100%DWT with three hawser lengths, i.e., 15, 20, and 25% of the length of FPSO. Model tests were conducted in a 2 m wide wave flume at a water depth of 1 m for wave frequencies from 0.55 to 1.25 Hz in steps of 0.04 Hz for head sea condition. The motions were measured by rotary type potentiometers and a ring type load cell was used to measure the hawser line force. The experimental results of motions and hawser line force of FPSO moored for the two mooring arrangements are compared and presented with discussions. [ABSTRACT FROM AUTHOR]

Abstract: In the early stages of the selection process for the hardware to exploit an offshore petroleum reservoir, it is important to be able to identify rapidly which production facility type(s) are likely to deliver the greatest value. This paper explores key features and constraints of the ten common fixed, floating and subsea facility options. Both shallow and deepwater are considered, along with regional variations. It is shown that facility applications may be categorised in a very simple matrix form, with the water depth and well count being particularly important drivers of facility choice. [Copyright &y& Elsevier]

The article discusses developments in Kenyan shipping industry with particular focus on the LAPSSET project dedicated to constructing a port in the Lamu Island. Special attention is paid to the statement of Kenyan president Uhuru Kenyatta that local corporations are linked to massacres in the port area. A review of highways and roads linking African countries is also presented.