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She holds a B.Eng. in building engineering from Tongji University (2001), a M.S. in civil engineering from the University of Massachusetts (2005), and a Ph.D. in geotechnical engineering from the Georgia Institute of Technology (2010). Dr. Tan's areas of specialization include deep excavation and tunnelling, foundation engineering, forensic geotechnical engineering, and engineering failures associated with climate change. He received his B.Eng. in building engineering from Tongji University (1999), M.Eng. in Geotechnical Engineering from Tongji University (2002), and Ph.D. in civil engineering from the University of Massachusetts (2005). [Extracted from the article]

Research on collaborative manufacturing process modelling and simulation is of great significance in improving production efficiency and product quality, reducing costs, promoting collaborative work, and supporting decision-making. However, current studies have not offered the optimal costs of node enterprises participating in collaborative manufacturing, and ignored the impact of demand uncertainty of suppliers, manufacturers and customers on costs and economic benefits. Therefore, this paper aimed to study the collaborative manufacturing process modelling and simulation of production cost and economic benefit accounting analysis. First, this paper summarized three cost types, conducted cost accounting for the collaborative manufacturing process, and analysed its economic benefits. Second, based on the basic timed automata (TA) model, this paper used a timed input/output automata with port labels (Lp-TIOA) for modelling test cases of the simulation system. Finally, the experimental results verified the effectiveness of the constructed simulation model. [ABSTRACT FROM AUTHOR]

The objective of the present work is to analyse how changes in wave patterns due to the effect of climate change can affect harbour agitation (oscillations within the port due to wind waves). The study focuses on 13 harbours located on the Catalan coast (NW Mediterranean) using a methodology with general applicability. To obtain the patterns of agitation, a Boussinesq-type model is used, which is forced at the boundaries by present/future offshore wave conditions extracted from recently developed highresolution wave projections in the NW Mediterranean. These wave projections were obtained with the SWAN model forced by present/future surface wind fields projected, re spectively, by 5 different combinations of global and regional circulation models (GCMs and RCMs) for the A1B scenario. The results show a general slight reduction in the annual average agitation for most of the ports, except for the northernmost and southernmost areas of the region, where a slight increase is obtained. A seasonal analysis reveals that the tendency to decrease is accentuated in winter. However, the inter model variability is large for both the winter and the annual analysis and many ports present at least one model configuration showing a rise in the agitation. Conversely, a general increase is found during summer, which is the period with greater activity in most of the studied ports (marinas). The latter result is more consistent among models, which illustrates the lower inter-model variability in summer. [ABSTRACT FROM AUTHOR]

In this paper, a bibliometric, content and thematic analysis of digitalization in maritime transport and seaports was performed. The research was primarily motivated by the scarcity of similar works offering a comprehensive and recent literature analysis, the advancements of the maritime digitalization itself, and its influence on all related processes. The initial investigation phase considered 8178 publications, leading through the research steps to the final inclusion of 280 papers, the thematic and content analysis of which were performed using various bibliometric tools. The research encompassed various criteria, ranging through databases, keywords, topics, research areas and others. The resulting concept map emphasized the main concepts that digitalization in maritime transport relies on, or strives towards. The aim of the study was to address the fundamental research questions, with the tendency to define the main key points in the current maritime transport and seaport digitalization process. It can be concluded that an increasing number of authors recognize the importance of new digital technologies in maritime transport and seaports. However, with new digital technologies come specific risks such as spoofing or data manipulation that need to be further analyzed. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyse the main scientific contributions in the field of sustainable seaports, with a particular focus on passenger seaports and passenger seaports' commitment to sustainability. The focus of this analysis is on the methods used to improve and develop a sustainable seaport. A search of the Web of Science Core Collection that addresses this topic consists of scientific articles published from 2012 to 2022. The articles are divided into seven groups by research area (technical/technological, legal, organisational, economic, social, environmental, and other) and five groups by applied methodology (literature review, theoretical approach, qualitative approach/methods, quantitative approach/methods, and other). The results show that most of the papers were published in the field of the environmental impacts of a sustainable seaport and a sustainable passenger seaport. In addition, most papers used quantitative approach/methods. [ABSTRACT FROM AUTHOR]

Network security is paramount in today's digital landscape, where cyberthreats continue to evolve and pose significant risks. We propose a DPDK-based scanner based on a study on advanced port scanning techniques to improve network visibility and security. The traditional port scanning methods suffer from speed, accuracy, and efficiency limitations, hindering effective threat detection and mitigation. In this paper, we develop and implement advanced techniques such as protocol-specific probes and evasive scan techniques to enhance the visibility and security of networks. We also evaluate network scanning performance and scalability using programmable hardware, including smart NICs and DPDK-based frameworks, along with in-network processing, data parallelization, and hardware acceleration. Additionally, we leverage application-level protocol parsing to accelerate network discovery and mapping, analyzing protocol-specific information. In our experimental evaluation, our proposed DPDK-based scanner demonstrated a significant improvement in target scanning speed, achieving a 2× speedup compared to other scanners in a target scanning environment. Furthermore, our scanner achieved a high accuracy rate of 99.5% in identifying open ports. Notably, our solution also exhibited a lower CPU and memory utilization, with an approximately 40% reduction compared to alternative scanners. These results highlight the effectiveness and efficiency of our proposed scanning techniques in enhancing network visibility and security. The outcomes of this research contribute to the field by providing insights and innovations to improve network security, identify vulnerabilities, and optimize network performance. [ABSTRACT FROM AUTHOR]

Ports play a significant role in facilitating international trade and economic development, serving as vital gateways for the movement of goods across the continent and beyond. As global trade volumes continue to rise, efficient port operations hold the potential to not only enhance economic growth but also contribute significantly to job creation across various sectors of the economy. This paper examines the impact of container port throughput on employment in Africa and further tests whether causality runs from employment to container port throughput. To do so, we use a sample of 27 African countries with seaport and data spanning the period from 2010 to 2020 for the analysis. The system- Generalized Method of Moments (SGMM) estimation technique is used as the estimation strategy. We use service, industrial, and total employment percentages of the total population as proxies for employment while annual container throughput measured in Twenty foots Equivalent Units (TEUs) is used as an indicator for port throughput. Based on the empirical results, we establish a positive significant effect of port throughput on employment in Africa. We further show that bidirectional causality exists between port throughput and employment in Africa. Following these findings, we recommend policies that increase port throughput in Africa. [ABSTRACT FROM AUTHOR]

Different types of stealth films and their electromagnetic (EM) behavioral characteristics have been studied to fulfil the stealth requirements of today's electronic warfare (EW) for military mission success. The EM performance of stealth films has been measured using two different measurement methods: wave guide measurement (WGM) and open area test site (OATS). Polyethylene terephthalate (PET) (sample B1) has been used as the base material to design and fabricate composite stealth films, films N (PET + conductive paint), S (PET + conductive paint + fumed silica), Q (PET + conductive paint + aluminum), and P (PET + conductive paint + aluminum + fumed silica). The conductive paint and fumed silica are used to design and fabricate small unmanned aerial vehicle (sUAV) model stealth frames. The detailed parametric studies of these films and frames have been analyzed in terms of EM wave parameters, S11 (reflection coefficient), S21 (transmission coefficient), I1 (input power at port 1), O1 (output power at port 1), O2 (output power at port 2), Pin (input power incident on sample specimen), Prefle (reflected power at a point close to the transmitter), Ptrans (power transmitted through the sample), SErefle (shielding effectiveness of reflection loss), SEabs (shielding effectiveness of absorption loss), SEtot (total shielding effectiveness), and RCS (σ) (radar cross-section). These parameters have been verified in the X-band frequency operation in the 8- to 12-GHz frequency range. Using these stealth films and frames, the minimum values of S11, S21, and SEtot of − 40 dB, − 0.6 dB, and 0.7 dB, respectively, in WGM and − 75 dB, − 76 dB, and − 75 dB, respectively, in OATS, were achieved. Further, the achieved RCS reduction level falls in the range of 0.09–1.5 m2 over the 8–10.1 GHz frequency range, and in the range 1.6–4 m2 above 10.1 GHz and up to 12 GHz, as presented in this paper. The experimental results give a good agreement between the design material and their EM behaviors, so their suitability for stealth applications is justified. [ABSTRACT FROM AUTHOR]

In recent years, the throughput of cargo ports has increased rapidly. It is urgent to improve the operating efficiency of ports for its increasing demands. Both industry and academia have shown great interest in adopting 5G and Virtual Reality (VR) technologies to improve the efficiency and safety of industrial operations. However, such technologies have not been well explored in port operations. This paper proposes a 5G-based VR smart port to support intelligent management for five typical port operations. The overall architecture of the smart port and its key processes, major advantages, and limitations are discussed in this paper. An application of the proposed smart port system is demonstrated. The performance study based on network Quality of Service (QoS) and Quality of user Experience (QoE) proves the feasibility of the proposed architecture. The architecture supports efficient interaction in real-time, making comprehensive decisions, and staff training. The smart port architecture is suitable for tasks of high working intensity and can dramatically increase operational efficiency. [ABSTRACT FROM AUTHOR]

The detection of harbors presents difficulties related to their diverse sizes, varying morphology and scattering, and complex backgrounds. To avoid the extraction of unstable geometric features, in this paper, we propose an unsupervised harbor detection method for polarimetric SAR images using context features and polarimetric reflection symmetry. First, the image is segmented into three region types, i.e., water low-scattering regions, strong-scattering urban regions, and other regions, based on a multi-region Markov random field (MRF) segmentation method. Second, by leveraging the fact that harbors are surrounded by water on one side and a large number of buildings on the other, the coastal narrow-band area is extracted from the low-scattering regions, and the harbor regions of interest (ROIs) are determined by extracting the strong-scattering regions from the narrow-band area. Finally, by using the scattering reflection asymmetry of harbor buildings, harbors are identified based on the global threshold segmentation of the horizontal, vertical, and circular co- and cross-polarization correlation powers of the extracted ROIs. The effectiveness of the proposed method was validated with experiments on RADARSAT-2 quad-polarization images of Zhanjiang, Fuzhou, Lingshui, and Dalian, China; San Francisco, USA; and Singapore. The proposed method had high detection rates and low false detection rates in the complex coastal environment scenarios studied, far outperforming the traditional spatial harbor detection method considered for comparison. [ABSTRACT FROM AUTHOR]

Denmark has set a target of 4–6 GW electrolysis capacity by 2030, of which a part of the produced hydrogen is to be used for export, while the rest could be transformed further into electrofuels. The North Denmark Region has favourable conditions for the production of carbon-based fuels. The region has high availability of CO2 sources and a strategic position for establishing CO2 hubs in the local harbours that could support biogenic CO2 availability in the future. This paper investigates the potential of the region for exporting e-methanol through 22 energy system scenarios and the impacts on the energy system if this is to be realised by 2030 and 2045, when Denmark is expected to achieve its national climate goals. The analysis highlights the significant potential of this region to contribute to e-methanol production not only to meet the regional demand for methanol for marine transport and aviation but also for export to the rest of Denmark or beyond Danish borders. [ABSTRACT FROM AUTHOR]

Global seaport network efficiency can be measured using the Liner Shipping Connectivity Index (LSCI) with Gross Domestic Product. This paper utilizes k-means and hierarchical strategies by leveraging the results obtained from Data Envelopment Analysis (DEA) and Fuzzy Data Envelopment Analysis (FDEA) to cluster 133 countries based on their seaport network efficiency scores. Previous studies have explored hkmeans clustering for traffic, maritime transportation management, swarm optimization, vessel trajectory prediction, vessels behaviours, vehicular ad hoc network etc. However, there remains a notable absence of clustering research specifically addressing the efficiency of global seaport networks. This research proposed hkmeans as the best strategy for the seaport network efficiency clustering where our four newly founded clusters; low connectivity (LC), medium connectivity (MC), high connectivity (HC) and very high connectivity (VHC) are new applications in the field. Using the hkmeans algorithm, 24 countries have been clustered under LC, 47 countries under MC, 40 countries under HC and 22 countries under VHC. With and without a fuzzy dataset distribution, this demonstrates that the hkmeans clustering is consistent and practical to form grouping of general data types. The findings of this research can be useful for researchers, authorities, practitioners and investors in guiding their future analysis, decision and policy makings involving data grouping and prediction especially in the maritime economy and transportation industry. [ABSTRACT FROM AUTHOR]

Although the port industry is very important in the Korean economy, there are few literature studies that shed light on the macroeconomic implications of the business cycles in this industry. This paper examines the roles played by foreign economic factors in the business cycle in the Korean port industry. Specifically, it aims to estimate the impulse response of the seaborne freight volume in the port industry due to the shocks of the foreign economy and analyze the contributions of each shock considered on the variation in the freight volume. The structural FAVAR (SFAVAR) model was employed to extract the unobserved foreign economic factors. This paper estimates the four foreign economic factors and the parameters of the model using the one-step Bayesian Gibbs sampling method. The findings of this study show that foreign economic activity statistically affects the freight volume of the Korean ports. Specifically, the shocks to the foreign real economic activity increased freight transportation for nearly one year. Following the world inflation shocks, the freight transportation was enhanced. However, this impact disappeared after a year. Similarly, the rise in global liquidity was shown to encourage transportation activity; nevertheless, this activity declined after five quarters. Moreover, the increase in the world interest rates exerted a negative effect on the volume of transportation. Furthermore, the variance decomposition analysis shows that 49.2% of the variation in the transportation volume could be attributed to foreign economic activity. This analysis can contribute to drawing useful implications in establishing the port industry policy in response to the change in the economic environment such as the foreign economy. [ABSTRACT FROM AUTHOR]

With the rapid development of global trade, the turnover of shipping containers has increased rapidly. How to use port resources reasonably and efficiently has become one of the main challenges that ports need to deal with when planning for the future. In order to develop scientific and efficient berth plans to improve operational efficiency and service level, this paper proposes a hybrid prediction model based on Principal Component Analysis (PCA) and Extreme Learning Machine (ELM) optimized by Improved Particle Swarm Optimization (IPSO), namely, the PCA-IPSO-ELM model. After assessing the uncertain factors influencing the operation time of the container ship at berth, this work reduces the dimensionality of the investigational data by the PCA method. Aiming to solve easy premature convergence of the traditional particle swarm algorithm, this paper introduces an improved particle swarm optimization algorithm via dynamic adjustment of nonlinear parameters. This improved particle swarm algorithm is mainly used to optimize the weights and thresholds of the extreme learning machine. Thus, a PCA-IPSO-ELM model which aims to forecast the operation time of a container ship at berth, is constructed. Using the historical operation data of the Tianjin Port Container Shipping Company as the prediction sample, this PCA-IPSO-ELM model is compared and assessed with traditional models. The results show that compared with other models, the PCA-IPSO-ELM prediction model has the characteristics of high prediction accuracy, fast running rate and strong stability, and it has a higher coefficient of determination and a better fitting degree. [ABSTRACT FROM AUTHOR]

Polarization processors with versatile functionalities are needed in optical systems, which use or manipulate polarized light. In this paper, we propose and realize an integrated polarization processor based on a coherent 4-port micro-ring resonator. The arbitrary unknown polarization state is input to the polarization processor via a 2-dimensional grating coupler (2DGC), which serves as a polarization beam splitter. The coherent 4-port micro-ring resonator (MRR) operates as a unitary processor and is formed by one crossbar micro-ring resonator and two thermally tunable phase shifters, one of which tunes the micro-ring while the other tunes the coherent interference between the two inputs from the 2DGC. The 4-port system can be used to control the input polarization states that appear at the two output ports and, therefore, can be used to implement a multi-function polarization processor, including polarization descrambler, polarization switch, polarizers, and polarization analyzer (both division of space (DOS) and division of time (DOT)). In this paper, we experimentally demonstrate the use of coherent 4-port MRR for polarization mode switching and for polarization mode unscrambling. The polarization unscrambler was capable of separating two polarization-multiplexed 40 GHz data lanes from the input fiber with crosstalk levels below −21 dB and is suitable for use in the receiver for polarization-multiplexed direct-detection optical communications systems. The same photonic circuit may be used as a polarization analyzer, either as a DOS polarization analyzer or a DOT polarization analyzer. The DOS polarization analyzer measured the polarization with measured deviation of the orientation angle (2ψ) varying from −0.5° to 1.3°and deviation of ellipticity angle (2χ) varying from −0.98° to 7.27°. The DOT polarization analyzer measured the polarization with a deviation of the orientation angle (2ψ) that varied from −2.93° to 3.49° and deviation of ellipticity angle (2χ) that varied from −3.5° to 3.05°. [ABSTRACT FROM AUTHOR]

Positive displacement compressors are essential in many engineering systems, from domestic to industrial applications. Many studies have been devoted to providing more insights into the workings and proposing solutions for performance improvements of these machines. This study aims to present a systematic review of published research on positive displacement compressors of various geometrical structures. This paper discusses the literature on compressor topics, including leakage, heat transfer, friction and lubrication, valve dynamics, port characteristics, and capacity control strategies. Moreover, the current status of the application of machine learning methods in positive displacement compressors is also discussed. The challenges and opportunities for future work are presented at the end of the paper. [ABSTRACT FROM AUTHOR]

In this paper, a high gain nonisolated three-port bidirectional DC–DC converter is proposed to interface solar photovoltaic and battery energy storage system to DC bus with a reduced number of components. Four modes of operation based on the power flow and load demand are identified. The operating principle of the proposed converter and its operational waveform for all four modes of operation is described in this paper. The steady-state analysis of the proposed converter is performed to determine the voltage gain of the converter in all four modes of operation. The steady-state analysis is done for both continuous conduction mode and discontinuous conduction mode; and the boundary condition. The reduced number of components to achieve high-voltage gain ensures the lowering of the cost and weight of the converter. The analytical results are validated utilizing the simulation results from PSCAD and hardware results. Also, the results indicate that the ripple in the current and voltage is reduced significantly. [ABSTRACT FROM AUTHOR]

Partial electrification of hydraulic circuits to achieve energy savings requires an increase in the angular speed of the positive displacement pumps, with the risk of incomplete filling. In this context, the paper focuses on developing a computational fluid dynamics (CFD) model using SimericsMP+ for two external gear pumps, namely helical and spur type gears. The objective of this study is the analysis of the phenomena occurring on the suction side under conditions of incomplete filling at high speeds. Both CFD models have been validated by conducting experimental tests for measuring the flow rate delivered at various inlet pressures and angular speeds. The experimental results confirm the model's capability to accurately detect the operating conditions at which the delivered flow rate starts to decrease due to the partial filling of the inter-teeth chambers. Furthermore, this paper investigates the effects of certain geometrical modifications to the spur gear pump. Specifically, the influence of the gear's width-to-diameter ratio is studied, revealing that a lower ratio leads to slightly better filling. Conversely, increasing the inlet port diameter results in no improvement. Based on this study, the modelling approach appears to be accurate enough to serve as design tool for optimizing pumps to improve their filling capability. [ABSTRACT FROM AUTHOR]

The current paper presents the results of a study that analyzed and evaluated the efficiency of the largest container ports in the wider area of the Mediterranean Basin. The research question that this paper seeks to respond to is how the resources (inputs) of a container port reflect its level of activity and efficiency. In particular, what is the relationship between ports' infrastructures, equipment and their productivity and the ports' ability to attract economic activities as well as the extent of their effect on a port's efficiency? The methodology uses the data envelopment analysis (DEA) output-oriented model following a cross-sectional approach. The research conducts two modeling approaches, the CCR and the BCC model. The analysis goes deeper and compares port efficiency estimates in relation to medium-sized and large ports' classification and their total market share. The main findings indicated an average efficiency of 0.88 and 0.89 assuming constant and variable returns of scale, respectively, implying that the ports can increase their output levels up to approximately 1.2 times without any change in their inputs. [ABSTRACT FROM AUTHOR]

With growing concerns over environmental degradation and climate change, the shipping industry is under increasing pressure to reduce its environmental impact. This has led to the development of green port initiatives in the field of maritime transport and logistics, which aim to promote sustainable practices and reduce the environmental footprint of ports and their operations. One of the key strategies for achieving this goal is the use of renewable energy technologies (RETs). This paper summarizes the potentials, challenges, and economic analysis of RETs applications in green ports, emphasizing those that require aquatic environments for operation, including floating photovoltaic systems, offshore wind turbines, and ocean energy. The paper investigates the concept of green ports and explores the feasibility of integrating RETs into these facilities. Also, the potential of the various RETs is presented in terms of technical and economic aspects and installed capacity. Additionally, due to high flexibility in electrical systems and compatibility with maritime transportation, the use of fuel cells in green ports has been discussed as a feasible solution for supplying power to ports (either as the primary or backup source). The findings of this study show that RETs can significantly contribute to achieving sustainable goals in the maritime industry and pave the way for the creation of more efficient and environmentally friendly ports. [ABSTRACT FROM AUTHOR]

Although smart home has received wide attention in recent years, numerous scholars focus more on energy optimization strategy than energy dispatch hardware device (named energy router). Meanwhile, this energy router should have several features, i.e., high renewable energy utilization, energy multi-port and low volume. Thus, this paper designs a nine-port energy router regarding smart home and proposes a multimode hierarchical management strategy for this energy router. First, for the multi-port demand of wind, solar, storage and utilization, this paper presents a nine-port energy router to improve the renewable energy consumption and power supply flexibility. In addition, to reduce the volume of the energy router, a non-isolated AC/DC hybrid topology is constructed through embedding the integrated power electronic converters, which achieves the miniaturization of the energy router. In order to improve the renewable energy utilization rate, the decentralized module control is proposed for the components of energy router to provide the voltage and frequency support for system, and realizes the power sharing of distributed generations (DGs). Furthermore, the power exchange control with three-mode switching is proposed to guarantee the global energy flow balance under complex conditions. Eventually, the feasibility of the energy router is verified by the simulation and experiments. [ABSTRACT FROM AUTHOR]

This paper aims to examine numerous sustaining factors in the restabilisation of Afghanistan, from legal, logistical and technical perspectives. The significance of logistics and infrastructure for state reconstruction and stability has been recognised by military and engineering practices. However, previous research on Afghanistan has focused on specific areas such as geopolitics, regional studies, bilateral cooperation and international aid. In contrast, this paper examines specialised issues within logistics and infrastructure, i.e., transit rights, access to ports, investors' codes of conduct and the modus operandi of military and engineering engaged in the construction, operation and protection of infrastructure, which have not yet been fully discussed in the previous research. Furthermore, the importance of logistics of multiple shipping routes will be examined through comparative analysis. Considering a prolonged restabilisation process in land-locked Afghanistan, rights of transit and port access are imperative to achieve safe logistics in energy, water, food and medical supplies. In conclusion, an integrated, comprehensive model agreement for multilateral cooperation would enable international aid to be funnelled via a single scheme. Thus, this paper concludes that the long-term stability and development of Afghanistan will be guaranteed through a comprehensive framework agreement for logistics, which materialises rights of transit and port access. [ABSTRACT FROM AUTHOR]

The tsunamis that have occurred in many places around the world over the past decade have taken a heavy toll on human lives and property. The eastern coast of the Korean Peninsula is not safe from tsunamis, particularly the eastern coastal areas, which have long sustained tsunami damage. The aim of this study was to mitigate the casualties and property damage on the east eastern coast by developing a proper tsunami response system for important ports and harbors with high population densities and high concentrations of key national industries. For study purposes, the governmentmanaged major international trade ports and coastal harbors were selected and an effective tsunami response system was formulated based on field surveys and related literature. [ABSTRACT FROM AUTHOR]

Conclusions All of the papers selected for this Special Issue have shown important insights and contributed to making this Special Issue successful in providing a platform for recent advances in the field of power electronics for electric drives and renewable energy sources, concerning both consumption and generation. This Special Issue was intended to consolidate the most recent advances in the field of power electronics for electric drives and renewable energy sources. In ref. [[3]], a design method for the cogging torque minimization of permanent magnet machines with a segmented stator core based on artificial neural network surrogate models is proposed. [Extracted from the article]

With the rapid development of global trade, a large number of goods and resources are imported and exported via seaports. Multiple thermal loads and renewable energy merge into seaports, making the energy supply and demand structure increasingly complex. The traditional seaport becomes an integrated seaport energy system (ISES). Due to the complicated energy interaction of cooling, heating, electricity, and gas subsystems, the ISES urgently require reliable and secure operation. Hence, this paper proposes a new reliability assessment method for the ISES that considers thermal inertia. Firstly, the operational structure of the ISES is established considering multi-energy coupling relationships. Then, a two-stage optimal load curtailment model is constructed with multiple thermal inertias. In addition, the reliability assessment method for the ISES is proposed based on the sequential Monte Carlo simulation method. Simulations are presented to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Actual security ensures individuals, information, frameworks, and gear of a country. It additionally gets worldwide boundaries. Political obstruction and infringement of boundary arrangements can make line security issues. Mechanical headways in actual security diminish the weight of line security work force. On the off chance that the boundary of a nation is not all around ensured, then, at that point, it would confront a progression of illicit movement. Boundaries can be emphatically ensured by utilizing actual obstructions, observation, biomeasurements, light, security faculty, caution frameworks, sensors, radars, access control frameworks, distinguishing proof frameworks, and PC design. This paper talks about certain difficulties and their potential arrangements utilizing different actual security components at global boundaries. This paper likewise indicates the possible changes in genuine which nations' security can consider for their lines the bosses in a common manner. [ABSTRACT FROM AUTHOR]

Due to the complex hydrology and narrow channels of inland rivers, ship collision accidents occur frequently. The traditional collision-avoidance algorithms are often aimed at sea areas, and not often at inland rivers. To solve the problem of inland-ship collision avoidance, this paper proposes an inland-ship collision-avoidance decision system based on the velocity obstacle algorithm. The system is designed to assist ships in achieving independent collision-avoidance operations under the limitation of maneuverability while meeting inland-ship collision-avoidance regulations. First, the paper improves the Maneuvering Modeling Group (MMG) model suitable for inland rivers. Then, it improves velocity obstacle algorithms based on the dynamic ship domain, which can deal with different obstacles and three encounter situations (head-on, crossing, and overtaking situations). In addition, this paper proposes a method to deal with close-quarters situations. Finally, the simulation environment built by MATLAB software is used to simulate the collision avoidance of inland ships against different obstacles under different situations with a decision-making time of less than 0.1 s. Through the analysis of the simulation results, the effectiveness and practicability of the system are verified, which can provide reasonable collision-avoidance decisions for inland ships. [ABSTRACT FROM AUTHOR]

In general, the structures of Multi-Active Bridge (MAB) converters that can be found in the literature are usually based on voltage converters. However, in some cases, it could be interesting to have a current-fed input due to load characteristics or operation constraints. This leads to a hybrid MAB structure mixing both current-fed and voltage-fed bridges. In this paper, a new hybrid-fed, fully coupled Triple-Active Bridge (TAB) converter topology with two voltage-fed ports and one current-fed port is studied, modelled and controlled. In the first place, a generalized average model (GAM) is developed for this system. After that, a reduced-order model is elaborated in order to simplify the behavioral study and control of this coupled system. A control strategy was also proposed in this paper, based on the developed mathematical model. Simulation results using Matlab/Simulink are presented to validate this study. [ABSTRACT FROM AUTHOR]

This paper presents an assessment of the quality of selected filtration methods for the postprocessing of multibeam echosounder data. In this regard, the methodology used in the quality assessment of these data is an important factor. One of the most important final products derived from bathymetric data is the digital bottom model (DBM). Therefore, quality assessment is often based on factors related to it. In this paper, we propose some quantitative and qualitative factors to perform these assessments, and we analyze a few selected filtration methods as examples. This research makes use of real data gathered in real environments, preprocessed with typical hydrographic flow. The methods presented in this paper may be used in empirical solutions, and the filtration analysis may be useful for hydrographers choosing a filtration method for DBM interpolation. The results showed that both data-oriented and surface-oriented methods can be used in data filtration and that various evaluation methods show different perspectives on data filtration quality assessment. [ABSTRACT FROM AUTHOR]

With extensive access to distributed power sources and the rising electricity load, the structure and tide of distribution networks are becoming increasingly large and complex, leading to great challenges for fault location methods. In this paper, the power coupling phenomenon of the T-section in the distribution network is studied, and a hierarchical optimization model for fault location is proposed based on the port equivalence principle, which divides the fault location into two levels—area location and section location—to reduce the fault search dimension. Then, an improved binary particle swarm optimization algorithm (IBPSO) applied to the area location is proposed to improve the convergence accuracy and speed by optimizing the convergence criterion and integrating the chaotic mapping and mutation strategies. Finally, based on the topological characteristics of the sections in the fault area, a fault candidate scenario screening method based on the fault confidence factor is proposed to realize a second dimensionality reduction in the section location link. Simulation tests show that the proposed method demonstrates a good dimensionality reduction effect for large-scale, active distribution networks; additionally, the accuracy rate is improved by 25.7% and the location speed is improved by 300 ms when compared with traditional fault location methods. [ABSTRACT FROM AUTHOR]

A new control algorithm was designed to solve the problems of actuator physical failure, remote network attack, and sudden change in trajectory curvature when a port's artificial intelligence-based transportation robots track transportation in a freight yard. First of all, the nonlinear, redundant, saturated sliding surface was designed based on the redundant information of sliding mode control caused by the finite nature of control performance; the dynamic acceleration characteristic of super-twisted sliding mode reaching law was considered to optimize the control high frequency change caused by trajectory mutation; and an improved super-twist reaching law was designed. Then, a nonlinear factor was designed to construct a nonlinear, fault-tolerant filtering mechanism to compensate for the abnormal part of the unknown input that cannot be executed by adaptive neural network reconstruction. On this basis, the finite-time technology and parameter-event-triggered mechanism were combined to reduce the dependence on communication resources. As a result, the design underwent simulation verification to verify its effectiveness and superiority. In the comparative simulation, under a consistent probability of a network attack, the tracking accuracy of the algorithm proposed in this paper was 22.65 % , 12.69 % and 11.48 % higher those that of the traditional algorithms. [ABSTRACT FROM AUTHOR]

Automated surveillance systems based on machine learning and computer vision constantly evolve to improve shipping and assist port authorities. The data obtained can be used for port and port property surveillance, traffic density analysis, maritime safety, pollution assessment, etc. However, due to the lack of datasets for video surveillance and ship classification in real maritime zones, there is a need for a reference dataset to compare the obtained results. This paper presents a new dataset for estimating detection and classification performance which provides versatile ship annotations and classifications for passenger ports with a large number of small- to medium-sized ships that were not monitored by the automatic identification system (AIS) and/or the vessel traffic system (VTS). The dataset is considered general for the Mediterranean region since many ports have a similar maritime traffic configuration as the Port of Split, Croatia. The dataset consists of 19,337 high-resolution images with 27,849 manually labeled ship instances classified into 12 categories. The vast majority of the images contain the port and starboard sides of the ships. In addition, the images were acquired in a real maritime zone at different times of the year, day, weather conditions, and sea state conditions. [ABSTRACT FROM AUTHOR]

Considering last year’s climate changes, we can expect low temperatures during winter, which can lead to the freezing of Danube river and more. This would prevent the freight traffic in Danube’s ports meaning that the riparian economy would suffer. This paper presents a new concept of breaking the ice. Using an existent tug, we propose the attachment of an icebreaking additional structure. The paper further describes the concept and includes the necessary calculation methods used for the technological design of this ensemble. This concept presents numerous advantages, including the financial aspect. [ABSTRACT FROM AUTHOR]

Featured Application: The platform is applied in the Maritime Silk Road Transport environmental security service system. This system provides global navigation assurance and environmental protection services. Since the e-Navigation strategy was put forward, various countries and regions in the world have researched e-Navigation test platforms. However, the sources of navigation data are multi-source, and there are still difficulties in the unified acquisition, processing, analysis and application of multi-source data. Users often find it difficult to obtain the required comprehensive navigation information. The purpose of this paper is to use e-Navigation architecture to design and develop maritime data security management platform, strengthen navigation safety guarantee, strengthen Marine environment monitoring, share navigation and safety information, improve the ability of shipping transportation organizations in ports, and protect the marine environment. Therefore, this paper proposes a four-layer system architecture based on Java 2 Platform Enterprise Edition (J2EE) technology, and designs a unified maritime data storage, analysis and management platform, which realizes the intelligent, visualized and modular management of maritime data at shipside and the shore. This platform can provide comprehensive data resource services for ship navigation and support the analysis and mining of maritime big data. This paper expounds on the design, development scheme and demonstration operation scheme of the maritime data security management platform from the system structure and data exchange mode. [ABSTRACT FROM AUTHOR]

The ability to withstand and recover from disruptions is essential for seaport energy systems, and in light of the growing push for decarbonization, incorporating clean energy sources has become increasingly imperative to ensure resilience. This paper proposes a resilience enhancement planning strategy for a seaport multi‐energy system that integrates various energy modalities and sources, including heating, cooling, hydrogen, solar, and wind power. The planning strategy aims to ensure the reliable operation of the system during contingency events, such as power outages, equipment failures, or extreme weather incidents. The proposed optimization model is designed as a mixed‐integer nonlinear programming formulation, in which McCormick inequalities and other linearization techniques are utilized to tackle the model nonlinearities. The model allocates fuel cell electric trucks (FCETs), renewable energy sources, hydrogen refueling stations, and remote control switches such that the system resilience is enhanced while incorporating natural‐gas‐powered combined cooling, heating, and power system to minimize the operation and unserved demand costs. The model considers various factors such as the availability of renewable energy sources, the demand for heating, cooling, electricity, and hydrogen, the operation of remote control switches to help system reconfiguration, the travel behaviour of FCETs, and the power output of FCETs via vehicle‐to‐grid interface. The numerical results demonstrate that the proposed strategy can significantly improve the resilience of the seaport multi‐energy system and reduce the risk of service disruptions during contingency scenarios. [ABSTRACT FROM AUTHOR]

Sustainable mobility is one of the key elements determining the correct operationalization of the idea of sustainable development. This concept also appears more and more often in modern cities, whose authorities strive to improve the quality of life of their inhabitants, among others by creating SUMP -Sustainable Urban Mobility Plan. This is followed by all kinds of facilities that generate big traffic in cities. One of the institutions willing to meet the challenges of the ever-growing number of trips in its vicinity is Gdynia Maritime University (GMU), which is one of the largest employers in this seaport city, and thus - is one of the biggest traffic generators. The objective of this paper is to investigate the prerequisites and perspectives of creating and implementing mobility plan for GMU in order to make transport more sustainable in its vicinity. For this purpose, pilot research survey has been carried out among employees and students regarding their behaviour and transport preferences in reaching this destination. The research hypothesis stating that the transport habits of the GMU commuters are not compatible with the concept of sustainable mobility was confirmed. The implementation of a sustainable mobility plan in this institution will help to change the standards of traveling in the area of the University and will contribute to better quality of life in the city. It is recommended to enhance the c ooperation with the Gdynia C ity Hall in order to create a synergy effect and bring an added value to sustainable development of this congested seaport urban space. [ABSTRACT FROM AUTHOR]

Development of beamforming methods for towed sonar multiplet line arrays is stimulated by their increased use in undersea surveillance. Such methods employ various forms of narrowband optimal beamforming to resolve port/starboard ambiguity present when the array is conventionally beamformed. In this paper, we depart from the purely narrowband approach and discuss methods for port/starboard ambiguity rejection (PSAR) using a broadband formulation. The proposed methodology relies on subband beamforming for which we use non-adaptive variants of beamspace Minimum Variance Distortionless Response (MVDR) and the Linear Constraint Minimum Variance (LCMV) beamformers. We provide detailed description and comparison of both subband methods and establish a connection between them. The paper provides assessment of PSAR properties of the developed broadband beamformers using outputs of signal processing of both simulated and experimental sonar data. Experimental data for this work were obtained through the participation in the Littoral Continuous Active Sonar (LCAS) trials. [ABSTRACT FROM AUTHOR]

At present, marine autonomous surface ships (MASSs) play a huge role in marine shipping, surveying and mapping, safeguarding the rights and interests of marine space, and other maritime tasks. The cooperative operation of a swarm of MASSs can extend the scope of operation of the MASSs, and thus allow them to carry out more complex tasks. Path tracking is an important problem for the control of a swarm of MASSs. In this paper, the control of underactuated MASSs is decoupled, to control the heading and speed, respectively. First of all, in the path tracking, the improved arc LOS guidance law is introduced, and the heading torque controller is designed, so that the MASS can track the reference path efficiently and accurately. Then the single-path guided path tracking without formation of the swarm of MASSs is studied, the reference path of the swarm center tracking is defined, and the heave thrust controller of the swarm of MASSs is designed based on consensus theory, so that the surge velocity of the MASS can tend towards consistentcy, and finally converge to the desired speed. Finally, the effectiveness of the proposed control strategy is verified by two groups of simulation experiments. [ABSTRACT FROM AUTHOR]

The rotary engine (RE) is a potential power plant for unmanned aerial vehicles (UAVs) and automobiles because of its structural and design merits. However, it has some serious drawbacks, such as frequent maintenance requirements and excessive fuel consumption. This review paper presents the current status of hydrogen-fueled rotary engine (HRE) technology and identifies the existing research and development gaps in combustion efficiency and performance of this engine that might benefit transportation sector. Focusing primarily on the research from past ten years, the crucial challenges encountered in hydrogen-powered rotary engines have been reviewed in terms of knock, hydrocarbon (HC) emissions, and seal leakages. The paper identifies the recent advances in design concepts and production approaches used in hydrogen-fueled rotary engines such as geometric models of trochoid profiles, port configurations, fuel utilization systems, and currently available computational fluid dynamics (CFD) tools. This review article is an attempt to collect and organize literature on existing design methods up to date and provide recommendations for further improvements in RE technology. [ABSTRACT FROM AUTHOR]

Designed for increased speed and capacity, 5G has the potential to significantly expand the way the data will be processed and transported, and will allow a wide range of new use cases, which go far beyond the smartphone, already targeted by the 3G and 4G technologies. The present paper focused on the development of new antenna technologies for millimeter waves 5G communications. In this direction, a new two-ports Multiple Input Multiple Output (MIMO) antenna functioning in the mm-wave band is proposed in this paper to support 5G communications at 38 GHz. The proposed MIMO configuration has a size of 43x25 mm² is printed on FR4 substrate material with a 0.8 mm thickness, a dielectric loss tangent of 0.02 and a relative permittivity of 4.4. By incorporating combinations of rectangular and triangular shaped slots into the patch elements and a partial ground plane with a rectangular slot, the desired band operation is achieved with enhanced gain and bandwidth. The considered antenna in this paper has a bandwidth of 3.38 GHz (36.8 GHz-40.18 GHz) in the desired band of 5G applications with isolation less than - 24 dB and peak gains of 4.85 dBi at 38.5 GHz. The proposed MIMO antenna covers many countries band like UK (37-40), USA (37-37.6), Canada (37.6-40.0) and Australia (39 GHz). [ABSTRACT FROM AUTHOR]

The paper's main aim is to present the impact on the city's road traffic generated by the Port of Gdynia's operations and propose the optimal solution for transport network development around the port. Firstly, the authors demonstrate a case study determining the impact of heavy goods vehicles (HGVs) generated by port facilities on local traffic. To this end, the average travel time of cars in the network on selected measurement sections is conditioned on the varying number of HGVs generated by the port. Next, based on the data obtained from the traffic monitoring system, PTV Vissim software is used as a modelling tool to analyse and assess the impact on local traffic. Finally, considering the analysis' results, the vulnerability of the transport network is discussed. The optimal solution for the transport network around the port's area is proposed. The paper is an extended version of the materials presented at the XIX Maritime Traffic Engineering Conference. [ABSTRACT FROM AUTHOR]

The paper describes the initial part of the research into the impact of the Port of Split marine traffic on the environment and the city. The Port of Split is situated in the middle of the Adriatic Sea and it is one of busiest marine traffic regions in the Mediterranean. The Port consists of six geographically separated basins, two of them for smaller vessels, other four for the international marine traffic. The paper presents type and size of vessels in basins, engine size, stay in Port and finally quantity of the international marine traffic air pollutant emission per each basin. The distribution of the international marine traffic and its air pollutant emission pinpoint exactly main sources of the emissions in the area around the city and its dependency on various factors linked to the vessels, showing that the city is encircled by with multiple pollution sources. [ABSTRACT FROM AUTHOR]