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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]

An eight-way hybrid microstrip/substrate integrated waveguide (SIW) power divider with good output isolation performance is proposed in this paper. The circuit consists of microstrip/SIW transitions and a cross-shaped SIW cavity. The good isolation characteristics is obtained by adding the resistors between the microstrip lines and the isolation resistors on the radial slotlines. The equivalent circuit is given in this paper to analyse the proposed power divider. A prototype was fabricated and measured. The measurement results show that the insertion loss (IL) is about 1.5 dB from 9.1 GHz to 10.15 GHz, and the input return loss (RL) is higher than 20 dB. The isolation of adjacent ports on the same side, adjacent ports on the different side, and opposite ports are higher than 17.5, 19, and 15 dB, respectively. The error between measurement and simulation is acceptable. [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]

Background: Automobile terminals play a key role in global finished car supply chains. Due to their connecting character between manufacturers on the one side and distributers on the other side, they are continuously faced with volatile demand fluctuations and unforeseen dynamic events, which cannot be handled adequately by existing planning methods. Autonomous control concepts already showed promising results coping with such dynamics. Methods: This paper describes the causes of dynamics and the terminal systems' inherent shortcomings in dealing with such dynamics. On this basis, it derives terminal's demand for novel planning approaches and presents a new integrated autonomous control method for automobile terminals. This novel autonomous control approach combines yard and berth assignments. This paper evaluates the performance of the new approach in a small comprehensive generic scenario. It compares classical planning approaches with the new autonomous control approach, by using a discrete event simulation model. Moreover, it analyses all relevant parameters of the new approach in a full factorial experiment design. In a second step this paper proves the applicability of the combined autonomous control approach to real-world terminals. It presents a simulation model of a real-world terminal and compares the new method with the existing terminal planning approaches. Results: This paper will show that the autonomous control approach is capable of outperforming existing centralized planning methods. In the generic and in the real-world case the new combined method leads to the best logistic target achievement. Conclusions: The new approach is highly suitable to automobile terminal systems and helps to overcome existing shortcomings. Especially in highly dynamic and complex settings, autonomous control performs better than conventional yard planning approaches. [ABSTRACT FROM AUTHOR]

An X-band active phased array horn antenna with high power capacity and high peak power is proposed in this paper. At the horn aperture, the baffles are loaded to suppress higher-order modes and eliminate blind spots during beam scanning. Straight walls are added to improve impedance matching. Considering that the peak power that T/R modules can provide is very limited, the proposal of a dual-port waveguide breaks through the bottleneck of the power capacity of a single-port input for the first time. The proposed curved dual-port waveguide is used to connect the horn antenna and the T/R module, which is verified to improve the power capacity of the overall internal structure. Simulated and measured results show that VSWR ≤ 2 in the frequency range of 7.5–8.5 GHz. There is no grating lobe in the ±10° scanning range and the maximum gain drop does not exceed 0.4 dB. The power capacity of the proposed HPM array is 56.34 MW. The phased array antenna has the characteristics of flexible scanning, small size, and high gain, and can be applied in high-power microwave systems. [ABSTRACT FROM AUTHOR]

This paper models a single liner service design and operations problem. The model selects the ports to be included, their sequence, the sailing speed of vessels, the number of vessels and the amounts of cargo to transport by the service. The objective is to maximise profit. First, a relaxation with a mixed-integer nonlinear programming (MINLP) formulation is proposed. We show how to obtain the optimal speed value. Once this value is obtained, the mathematical programming formulation becomes a mixed-integer linear program (MILP). Then, a two-step exact algorithm is presented to solve the problem. Using real data, the optimal solution was found in less than 1 min for small-size problems and in few hours for relatively large-size problems. More tests were carried out on randomly generated data sets with up to 25 ports. The results of these tests are rather promising, and they enabled us to identify the performance limits of the algorithm. [ABSTRACT FROM AUTHOR]

Increasing freight volumes and challenging environments in seaports and container terminals worldwide require streamlined and reliable operations. Digital twins are seen as important drivers of the digitalization in seaports by providing a basis for higher transparency, control and data-driven decision making. In this context, however, the concept is rarely studied, and implementation issues are not comprehensively discussed. The paper presents an exploratory study of digital twins in seaports based on a literature review and case studies. The analysis reveals a standardization deficit for digital twin implementations, an inflationary and improper use of the term digital twin, and fields of research that need to be explored further. The application of optimization methods and the integration of simulation-based optimization in the field of seaports and container terminals is examined, due to its relevance for digital twins. Important lessons learned can be taken from the most advanced implementations, integrating simulations and emulations with optimization methods. An in-depth examination of multiple case studies and discussions with global port leaders yields valuable perspectives on the varied levels of digital twin implementations being applied today, including insights into the most advanced implementations currently being used in ports and container terminals. As a result of the analyses conducted, various research directions and a research agenda are presented. [ABSTRACT FROM AUTHOR]

The paper analyses the data on ship and passenger availability in the busiest ports in the Republic of Croatia. In order to evaluate the variables related to cruiser traffic in seaports in the period from 2015 to 2023 in the Republic of Croatia, it was first necessary to determine the following most important variables of the proposed model: the port of Dubrovnik, the port of Split, the port of Zadar, the port of Rijeka and the port of Šibenik. The trends in passenger traffic from 2015 to 2023 for the five most important cruise ports in the Republic of Croatia were investigated. The values of the selected model variables were quantified on an index scale from zero to 100. This form of tourism is becoming more and more present on the international tourist market, offering numerous favourable opportunities, especially in the Mediterranean area. Due to its geo-traffic position, mild climate and rugged coastline, the Republic of Croatia is one of the most desirable cruising destinations in the world. The aim of this paper is to investigate and evaluate the cruise traffic variables of the busiest ports in the Republic of Croatia and to compare the observed ports with the port of Barcelona, as one of the most important ports for cruise ships in the Mediterranean. The conducted research indicates the constant growth of this form of tourism in the Republic of Croatia with the obligation to implement well-thought-out policies and strategies in order to achieve long-term sustainability. [ABSTRACT FROM AUTHOR]

This paper presented the benefits of a seaport in intermodal transport which is connected by railway with dry ports in the region of Western Balkans in order to increase its competitiveness. Port of Bar is considered as a case study. The aim of this paper was to confirm the hypothesis that a seaport connected to its hinterland by regular container trains has a competitive position, lower intermodal transport costs than a port connected to its hinterland by truck transport only. The special attention was given to the Serbian market, the main hinterland of Bar port. The comparative analysis of intermodal transport between the Port of Bar and the main economic centers in Serbia, confirmed the hypothesis. The use of rail transport for transport of containers is a prerequisite for increasing competitiveness of a seaport. [ABSTRACT FROM AUTHOR]

Ballast water is recognized as a major vector for the transfer of Harmful Aquatic Organisms and Pathogens (HAOP) and a source of sea pollution that negatively affects the environment and human health. Therefore, the International Maritime Organization (IMO) adopted the International Convention for the Control and Management of Ship's Ballast Water and Sediments (BWM Convention) in 2004. The BWM Convention introduced two standards, Ballast Water Exchange Standard (Regulation D-1) and Ballast Water Performance Standard (Regulation D-2). Ships are required to install Ballast Water Treatment (BWT) equipment in order to comply with Regulation D-2. However, the deadline for the installation of BWT is prolonged until September 2024, and many ships are still complying only with Regulation D-1. In addition, there are specific sea areas where Regulation D-1 cannot be complied with, and hence, HAOP could be easily transferred between ports. Consequently, it is essential to develop a system to protect the marine environment, human health and economy in coastal areas from the introduction of HAOP. This paper analyses ballast water discharged in the Port of Ploče (Croatia) according to ship type, age and flag they are flying. It was found that general cargo ships and bulk carriers discharged most of the ballast (87% of the total quantity) in the Port of Ploče. Moreover, discharged ballast water was analysed according to the origin, and it was found that 70% of discharged ballast originates from the Adriatic Sea. Based on the analysis of the research results and literature review, the ballast water risk assessment (BWRA) method was adopted, however, with certain modifications. The adopted method is modified by an additional risk factor (the deballasting ship's age), different risk scoring of the deballasting ship type and adding Paris MoU Grey and Black lists flag ships as high-risk ships. As a result, the BWRA method presented in the paper could be used as an early warning system and to facilitate the implementation of adequate measures to prevent pollution by discharged ballast water. [ABSTRACT FROM AUTHOR]

The International Mobile Telecommunications-2020 (IMT-2020) specifies the data rates for enhanced mobile broadband (eMBB) is approximately 10 Gb/s. Millimetre-wave (mmWave) has a vast spectrum and can be used with only slight authorisation, making it an ideal solution for eMBB. This paper proposes optimal detectors with low cost, low power consumption, and low complexity for mmWave massive multi-user multiple-input multiple-output (MU-MIMO) communication. The mmWave broadband communication faces many challenges in system implementation. One of the challenges of mmWave broadband systems is using the analog-to-digital converter (ADC) in the receiver. The ADC power consumption will significantly increase with the frequency bandwidth. The ADC power consumption will also considerably increase with the bit number used in the conversion simultaneously. The mmWave broadband communication also challenges the cost of transmitters, especially wideband linear amplifiers are costly. Hence, it is necessary to transmit a signal with a low peak-to-average power ratio (PAPR) to relax the linearity of the power amplifier. The radio-frequency (RF) port connects to two high-precision ADCs in conventional MIMO systems. Scaling such architectures to massive multiple-input multiple-output (MIMO) with hundreds or thousands of active antenna elements would lead to excessive-high power consumption and hardware costs. Hence, this paper proposes optimal detections for massive multi-user (MU) MIMO-GFDM communications with coarse quantisation. It achieves substantial cost and power savings and provides a high system capacity. The optimal detections for coarse quantisation in large-scale MU-MIMO-GFDM systems have minimal capability loss compared with the ideal case. There is no additional base-band processing complexity. The simulation results show that the SNR gap between the second mismatched quantiser and the precise quantiser is small. When the ratio of receiving and transmitting antennas is the same, the larger the number of antennas, the smaller the SNR difference between the second mismatch quantiser and the precise quantiser. [ABSTRACT FROM AUTHOR]

This paper explores the effects of six different cases of port water injection on the combustion, knock suppression and emissions of a supercharged gasoline direct injection (GDI) engine through numerical simulation. The six different intake port water injection cases included three vertical distances from cylinder center to water injector and two different injection directions. The results showed that cases 2 and 4 allowed more water and air to enter the cylinder and thus suppressed the knock, so the pressure oscillation was small. Case 2 had the largest turbulent kinetic energy in the center of the cylinder, which in turn facilitated the propagation of flame to the cylinder wall and suppressed the knock. The water injection cases shortened the combustion delay period compared to the no water cases. At the same time, the strong low temperature reaction of the end mixture produced a large amount of CH2O that decomposed into HCO. A high concentration and a large area of HCO distribution can predict the occurrence of a knock. In addition, the water injection cases (except for case 6) reduced the in-cylinder soot, unburned hydrocarbon (UHC) and CO emissions compared to the no water cases, but it increased NOX emissions. [ABSTRACT FROM AUTHOR]

The OECD project against BEPS has brought and initiated many changes - among others, in the OECD Transfer Pricing Guidelines. To react and respond to changes in the current business environment, a new chapter for transfer pricing in financial transactions has also been introduced (namely chapter X). This step can be considered beneficial. However, meeting all the requirements for setting a transfer price for financial transactions seems to remain a very demanding and expensive task. Furthermore, the OECD Transfer Pricing Guidelines have been of a general nature rather than providing responses to all potential problems and circumstances - they provide fundamental ideas and principles. Thus, the potential to apply a simplified procedure for setting a transfer price (even for financial transactions) can be viewed as desirable, both for taxpayers and tax authorities. The aim of the paper is linked to this idea - to present the results of a comparative study dealing with the rules for safe harbours for financial transactions (namely loans) as established worldwide, providing a summary of existing concepts and systematized criteria for a safe harbour to be considered. [ABSTRACT FROM AUTHOR]

The maritime sector is a vital component of the global economy. Its international nature supersedes state boundaries and any disruption in its operations could have consequent and collateral global effects, affecting the socio-economic wellbeing of regions, states and peoples. The increasing adoption of digitalisation in the sector, primarily increases efficiency, minimize cost and maximise benefit, while improving safety, simultaneously introduces a new cyber threat landscape. The attack surface has broadened further due to the COVID-19 pandemic, as recent, high-profile cyber attacks to shipping companies have indicated. Cybersecurity is not limited to technology but involves people and business processes. Hence, to mitigate the security risk introduced by cyber threat actors, the industry, like any other, should initially focus on identifying its most critical assets and then adopt risk mitigation measures, spreading from legislative initiatives to company-specific technology solutions. Industry-led initiatives should promote the adoption of cyber-related policies and mechanisms that focus on business continuity. It should be the role of international bodies, classification societies and national authorities to ensure compliance and full implementation of these measures. This paper adopts a System of Systems Analysis to carry out a vulnerability assessment of port and ship ecosystem, while providing insights on the role of the aforementioned entities. Our analysis decomposes the industry's major assets; ports and ships, to specific subcomponents which are used as the basis of the vulnerability assessment. According to our findings, this approach highlights that the majority of these subcomponents; ports and ships, are increasingly vulnerable to cyber attacks. [ABSTRACT FROM AUTHOR]

In multi‐input and multi‐output (MIMO) wireless power transfer (WPT) systems, the destructive interference between multiple transmitters and receivers brings a serious impact on power transmission efficiency. This paper proposes a voltage control strategy to maximize the transmission efficiency of a MIMO WPT system by controlling the amplitude and phase of the transmitter voltages. However, the complexity of the realistic WPT circuit topology and the uncertainty in the related parameters obstruct the establishment of an accurate closed‐form description of the WPT model to optimize the transmission efficiency of the system. In this paper, a simple multi‐port network model is introduced to simulate a MIMO system to avoid the complex circuit topology and a large number of circuit elements. To determine the parameters of the proposed model, a simple yet efficient methodology, by sequentially changing the excitations of the input ports and sampling the responses at the out ports, is proposed. A voltage control methodology to optimize the transmission efficiency of a MIMO wireless power transfer system is finally developed. To validate the proposed model and voltage control methodology, a three‐input and three‐output WPT prototype is designed and fabricated and used as the experimental platform. The performances of the proposed voltage control methodology are compared to both the experimental ones and those without the proposed voltage control methodology. [ABSTRACT FROM AUTHOR]

Ports and their oceanic hinterlands are distinctively malleable, permeable places. They are defined by morphologies that articulate shifting perspectives on the meanings of coastal settlements and their relationship to the term landscape. This essay introduces the co-editors' perspectives on port cities and the sea as distinctive modes of landscape, situating them, and the essays within the special issue, within a broader field of landscape studies. [ABSTRACT FROM AUTHOR]

The memristor is added to the port‐Hamiltonian systems to improve the disturbance suppression performance in this paper. The concepts of locally fixed‐time stability and locally fixed‐time H∞$H_{\infty }$ control of port‐Hamiltonian systems are presented. From this starting point, two novel memristor‐based locally fixed‐time controllers are designed to suppress the external disturbance of port‐Hamiltonian systems via the interconnection and damping assignment passivity‐based control technique. Comparing with the classical interconnection and damping assignment passivity‐based control methodology without memristor, there are some advantages. First, the settling‐time related to the memristor‐based controllers in stabilizing the same port‐Hamiltonian systems are shorter. Second, the memristor‐based controllers can make the oscillation in the case of the strong periodic disturbance be better suppressed. Theoretical analysis shows that the memristor‐based controller possesses good disturbance rejection performance owing to it can make the system states in a neighbourhood accelerate convergence to the desired equilibrium point. Two illustrative examples show that the theoretical results and the controllers designed in this paper work very well. [ABSTRACT FROM AUTHOR]

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Following the International Maritime Organization (IMO), in order to safeguard the realization of the Paris Agreement on climate protection, greenhouse gas (GHG) emissions have to be reduced by 50% by the year 2050. This objective shall be reached by decarbonization of maritime traffic, which is why ship operators currently increasingly search for alternative fuels. Moreover, since the start of the Ukrainian war in February 2022, this issue of alternative fuels has gained central importance in political agendas. A promising candidate for clean shipping that meets the IMO goals is ammonia since it is a carbon-free fuel. Ammonia (NH3) shows good advantages in handling and storage, and it ensures long sea voyages without any significant loss in cargo space for a reasonable price. Hence, ammonia has the potential to improve the environmental footprint of global shipping enormously. Induced by the introduction of stricter regulations in the so-called emission control areas (ECAs) in Northern Europe in 2015 as well as the renewed global sulfur cap, which entered into force in 2020, ship operators had to decide between different compliance methods, among which the most popular solutions are related to the use of expensive low-sulfur fuel oils, newbuilds and retrofits for the usage of liquefied natural gas (LNG) or the installation of scrubber technology. A change to ammonia as a marine alternative fuel represents an additional novel future option, but the successful implementation depends on the availability of NH3 in the ports, i.e., on the installation of the maritime NH3 infrastructure. Currently, the single German NH3 terminal with maritime access is located in Brunsbüttel, the western entrance to Kiel Canal. The distribution of NH3 from the existing NH3 hub to other German ports can be analyzed by the mathematical model of an inventory routing problem (IRP) that is usually solved by combinatorial optimization methods. This paper investigates the interrelated research questions, how the distribution of marine NH3 fuel can be modeled as an IRP, which distribution mode is the most economic one for the German ports and which modal mix for the NH3 supply leads to the greenest distribution. The results of this paper are empirically validated by data that were collected in several EU projects on sustainable supply chain management and green logistics. The paper includes a special section that is dedicated to the discussion of the economic turbulences related to the Ukrainian war together with their implications on maritime shipping. [ABSTRACT FROM AUTHOR]

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, the major ports around the world usually consist of multiple terminals and service centers which are often run by different operators. Meanwhile, inland terminals have been also developed to reduce port congestion and improve transport efficiency. The integrated planning of inter-terminal transport (ITT) between the seaport and inland terminals helps in providing frequent and profitable services, but also could lead to higher overall planning complexity. Moreover, the ITT system usually involves multiple stakeholders with different or even conflicting interests. Although an increasing number of studies have been conducted in recent years, few studies have summarized the research findings and indicated the directions for future research regarding ITT. This paper provides a systemic review of ITT planning: we examine 77 scientific journal papers to identify what kind of objectives should be achieved in ITT system planning, which actors should be involved, and what methodologies can be used to support the decision-making process. Based on the analysis of the existing research, several research gaps can be found. For example, the multi-modality ITT systems are rarely studied; cooperation frameworks are needed in the coordination of different actors and quantitative methodologies should be developed to reflect the different actors' financial interests. [ABSTRACT FROM AUTHOR]

Tian, X. and Zhao, R., 2015. Energy network flow model and optimization based on energy hub for big harbor industrial park. To model and optimize the energy network flow for the energy conservation and emissions reduction in big harbor industrial park by analyzing the characteristics of harbor energy system, this paper presents a universal framework for the modeling of energy systems comprising multiple-energy carriers, such as electricity, heat, gas, etc. The modeling framework is based on the energy hub concept model and the idea of 'energy flow network'. Then the system optimization to minimize energy consumption with multi-agent distributed control is put forward in this paper, which is executed with parallel processing method. After that, this paper takes Lingang industrial park in Shanghai as an engineering example to verify the whole energy model and optimization method proposed. In conclusion, the proposed approach can realize rational utilization of multiple-energy carriers for reducing energy consumption and carbon emissions, which can enhance the regulation level of energy center and make the energy system of the harbor run efficiently and orderly, that is to say, this paper can provide a technical support for the construction of resource saving and environment friendly harbor. [ABSTRACT FROM AUTHOR]

The rapid urbanization phenomenon has introduced multifaceted challenges across various domains, including housing, transportation, education, health, and the economy. This necessitates a significant transformation of seaport operations in order to optimize smart mobility and facilitate the evolution of intelligent cities. This conceptual paper presents a novel mathematical framework rooted in deep learning techniques. Our innovative model accurately identifies parking spaces and lanes in seaport environments based on crane positions, utilizing live Closed-Circuit Television (CCTV) camera data for real-time monitoring and efficient parking space allocation. Through a comprehensive literature review, we explore the advantages of merging artificial intelligence (AI) and computer vision (CV) technologies in parking facility management. Our framework focuses on enhancing container drayage efficiency within seaports, emphasizing improved traffic management, optimizing parking space allocation, and streamlining container movement. The insights from our study provide a foundation that could have potential implications for real-world applications. By integrating cutting-edge technologies, our proposed framework not only enhances the efficiency of seaport operations, but also lays the foundation for sustainable and intelligent seaport systems. It signifies a significant leap toward the realization of intelligent seaport operations, contributing profoundly to the advancement of urban logistics and transportation networks. Future research endeavors will concentrate on the practical implementation and validation of this pioneering mathematical framework in real-world seaport environments. Additionally, our work emphasizes the crucial need to explore further applications of AI and CV technologies in seaport logistics, adapting the framework to address the evolving urbanization and transportation challenges. These efforts will foster continuous advancements in the field, shaping the future of intelligent seaport operations. [ABSTRACT FROM AUTHOR]

The significance of the cross-border inland port linking southern Thailand and northern Malaysia has experienced notable expansion over time, mostly driven by economic development and the substantial increase in export demand from the far east market. Currently, there are ongoing development activities for the establishment of two additional inland ports at the Malaysian border. The current capacity of the Padang Besar Cargo Terminal (PBCT), an inland port, is insufficient to satisfy the demand. The Thai government has recently unveiled a series of new projects and enhancements to logistical infrastructures in the southern part of Thailand, which are indicative of the potential for economic growth in the area. The necessity to perform this study arises from the current advancements and the absence of empirical investigation into the parameters associated with the sustainability of a cross-border inland port. This study aims to examine the various difficulties and aspects that can potentially affect the long-term sustainability of a transnational inland port. It will explore the challenges, critical success factors, and impacts associated with cross-border inland ports. Upon the culmination of the investigation, a conceptual framework for cross-border inland ports is put out, alongside a comprehensive evaluation of its potential effects. This study takes a mixed methodology approach, utilizing interviews, on-site observations, desk research, and the Analytical Hierarchy Process (AHP) for data collecting and analysis. The findings of the study brought attention to the three fundamental elements of the framework, namely challenges, critical success factors, and impacts. Additionally, the responsibilities played by stakeholders were identified, along with a proposed strategy for establishing a sustainable cross-border inland port. This paper also provides an analysis of the impact assessment of a cross-border inland port, focusing on the three pillars of sustainability: people, planet, and profit. The research is expected to offer significant insights that can be utilized for strategic planning and decision-making by the relevant governing body and operators of inland ports. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to discuss the implications of COVID-19 on container import flows via the US port distribution system. We employ statistics collected for more than 21 US ports and for more than 550,000 container shipments by Walmart and Nike to identify trends and potential shifts in the US port distribution system. Results unveil different changes in distribution channels during the pandemic era, between aggregated port level and industry level. These differences are specific to firms and could be explained by the origin of flows, carrier selection to transport cargos and US port/inland distribution systems. Our study contributes to a better understanding of the different role played by ports for industries (retailers, footwear and apparel) and shows that the ability to adapt supply chains to a major disruption remains subject to the initial choices on the location of production, on carrier choices and on port/inland distribution networks. [ABSTRACT FROM AUTHOR]

This paper is concerned with the development of an optimal load-handling trajectory for port cranes. The objective is to minimize load cycle time and reduce energy consumption. Energetic macroscopic representation formalism is used to model a port crane load-handling mechanism. The crane model developed includes the mathematical model, the crane's local control system, and a MATLAB/Simulink model for simulation. The particle swarm optimization algorithm is used to find the set of pareto optimal crane trajectories given the variation in crane size, ship size, and wind speed. Experimental validation of the crane model is conducted by comparing it with a real-world crane. Simulation results show that the optimal crane load trajectory is 38% faster and more productive than the nonoptimal crane load trajectory. Furthermore, the results show that the optimal trajectory reduces the cranes' peak power and energy consumption by 36% when compared with the nonoptimal trajectory. [ABSTRACT FROM AUTHOR]

Hybrid Energy Storage Systems (HESSs) have gathered considerable interest due to their potential to achieve high energy and power density by integrating different storage technologies, such as batteries and capacitors, to name a few. Among the various topologies explored for HESSs, the multi-output multilevel converter stands out as a promising option, offering decoupled operation of the AC ports while maintaining an internal balance among the diverse storage units. In this paper, the operation and restrictions of a HESS based on a multi-output multilevel converter with a carrier-based modulation scheme are presented. The study provides compelling evidence of the correct operation of the proposed modulation scheme and highlights its advantages, including simplicity and stability. [ABSTRACT FROM AUTHOR]

The design and development of a non-isolated buck-based three-port dc–dc converter for medium-power standalone PV systems are presented in this paper. The topology is obtained from a parallel connection of conventional buck and boost converters. An attractive feature of this converter is the implementation of a buck topology at the PV side, which ensures cost-effective PV panel wiring, reduced converter development cost, and better efficiency of the PV system during low irradiation periods when compared to its boost counterpart. The proposed converter includes three operating modes based on load power requirements and PV power generation. An autonomous mode transition algorithm is proposed for seamless transitions between various operating modes. The design methodology, losses, and operation of the converter are discussed in this paper. A low-cost and efficient 2 kW laboratory prototype model of the proposed converter has been developed. Experimental validations are provided to showcase the effectiveness and viability of the proposed converter under various operating conditions. [ABSTRACT FROM AUTHOR]

In the forthcoming era of fully autonomous mining, spanning from drilling operations to port logistics, novel approaches will be essential to pre-empt hazardous situations in the absence of human intervention. The progression towards complete autonomy in mining operations must have meticulous approaches and uncompromised security. By ensuring a secure transition, the mining industry can navigate the transformative shift towards autonomy while upholding the highest standards of safety and operational reliability. Experiments involving autonomous pathways for mining machinery that utilize AI for route optimization demonstrate a higher speed capacity than manually operated approaches; this translates to enhanced productivity, subsequently fostering increased production capacity to meet the rising demand for metals. Nonetheless, accelerated wear on crucial elements like tires, brakes, and bearings on mining machines has been observed. Autonomous mining processes will require smarter machines without humans that guide and support actions prior to a hazardous situation occurring. This paper will delve into a comprehensive perspective on the safety of autonomous mining machines by using Bayesian networks (BN) to detect possible hazard fires. The BN is tuned with a combination of empirical field data and laboratory data. Various faults have been recognized, and their correlation with the measurements has been established. [ABSTRACT FROM AUTHOR]

Blast loadings have become the subject of research in recent decades due to the threats they pose to the surrounding medium. On 4 August 2020, a huge explosion occurred in the Port of Beirut that led to massive damages in the medium surrounding it. Researchers have conducted studies in order to estimate the equivalent explosive mass as well as the damage extent left on structures; however, the studies considered the soil–structure interaction by simple methods. For that, this paper aims to understand the effect of explosion on the grain silo structure present at the port with an emphasis on the soil–structure interaction effects. The structure consists of a group of silos resting on a raft footing that is supported by group of driven piles. A soil–structure model analysis is performed in order to investigate the soil behavior, the damage extent in piles, and the soil–structure interaction due to the Beirut explosion using the CEL (Coupled Eulerian–Lagrangian) approach that suits events involving large deformation. The analysis is performed using the ABAQUS/Explicit FEM software (version 6.14) taking into account the properties of soil medium, the contact algorithm at the soil–structure interface, and the boundary conditions in order to better simulate the real field conditions and ensure accurate results. The work is primarily validated through site data such as the crater size and silo damage. [ABSTRACT FROM AUTHOR]

Green port construction has a profound impact on China's international climate commitment to carbon neutrality by 2050. To examine the carbon emission reduction potential of 20 major ports in the Yangtze River Delta port cluster of China, this study takes the perspective of environmental efficiency and employs dynamic exogenous variable DEA in efficiency evaluation. The results show the increasing environmental efficiency of the ports in the Yangtze River Delta, rising from 0.5116 in 2013 to 0.7276 in 2019. Also, there are significant spatial differences in efficiency. After considering exogenous variable, the average efficiency has increased from 0.5537 to 0.6276, indicating that regional green development is a critical factor in port environmental efficiency evaluation. Finally, the overall efficiency of input and output have risen, the slackness of carbon emission shows a trend of decreasing, and there is great potential for reducing carbon emissions from the perspective of port environmental efficiency. The previous studies paid less attention to dynamic efficiency, exogenous variables, and carbon emission. Therefore, this paper is the first comprehensive examination on the carbon emission reduction potential of China's Yangtze River Delta port cluster from the perspective of dynamic environmental efficiency. [ABSTRACT FROM AUTHOR]

In this paper, the user-defined function (UDF) is firstly used to couple the porous medium model and the Euler–Euler two-fluid model, and the integrated SEN clogging model including the SEN clogging formation and growth, and liquid steel fluid flow dominated by the deposition of non-metallic inclusion particles is established. The simulation results of the SEN clogging under the Euler–Euler and Euler–Lagrange frameworks are both in good agreement with the measured results. With the increase of the distance from the nozzle inlet, the clogging thickness first increases, then remains stable, and slightly decreases. The clogging at the bottom of the nozzle is most serious and presents a conical shape. The polyhedral mesh is better than that of the hexahedral structure mesh for SEN clogging simulation. With the flow space of molten steel extruded and clogged, the molten steel jet is concentrated and strengthened under the constant steel throughput. The average inclination angle of molten steel jet from the nozzle side port first increases and then decreases slightly with time. The volume fraction of the clogging increases rapidly at first, and then the growth rate of the clogging decreases. [ABSTRACT FROM AUTHOR]

Low-code platforms aim at allowing non-experts to develop complex systems and knowledgeable developers to improve their productivity in orders of magnitude. The greater gain comes from using components developed by experts capturing common patterns across all layers of the application, from the user interface to the data layer and integration with external systems. Often, cloning sample code fragments is the only alternative in such scenarios, requiring extensive adaptation to reach the intended use. Such customization activities require deep knowledge outside of the comfort zone of low code. To effectively speed up the reuse, composition, and adaptation of pre-defined components, low-code platforms need to provide safe and easy-to-use language mechanisms. This paper introduces OSTRICH, a strongly typed rich templating language for a low-code platform (OutSystems) that builds on metamodel annotations and allows the correct instantiation of templates. We conservatively extend the existing metamodel and ensure that the resulting code is always well-formed. The results we present include a novel type safety verification of template definitions, and template arguments, providing model consistency across application layers. We implemented this template language in a prototype of the OutSystems platform and ported nine of the top ten most used sample code fragments, thus improving the reuse of professionally designed components. [ABSTRACT FROM AUTHOR]

A ship's automatic mooring system relies on vacuum suction pads with rubber seals to withstand external loads, such as mooring forces. This paper focused on the design requirements and performance testing of vacuum suction pads to develop a high-performance automatic mooring system and evaluated the performance of vacuum suction pads through real-scale testing. The mooring capacity of the target ship, the training ship HANBADA, was estimated based on the port and fishing port design standards of the Ministry of Oceans and Fisheries. Under the most extreme ocean conditions (beafort 6), the estimated longitudinal (surge) and lateral (sway) mooring forces acting on HANBADA were 17.7 and 248 kN, respectively. In the real-scale performance test, stable suction was achieved under both dry and water spraying conditions, with the suction force ranging from 180 to 200 kN, under sway conditions. The vacuum ratio remained satisfactory, indicating stable suction. However, under surge conditions, the vacuum ratio decreased slightly to 0.99. Furthermore, the rubber seals returned to their initial shape after load removal, demonstrating their effectiveness in the automatic mooring system. This study provides valuable insights into the design requirements and performance testing of vacuum suction pads, establishing their suitability for developing high-performance automatic mooring systems. [ABSTRACT FROM AUTHOR]

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Purpose: The purpose of this study is to quantify port efficiency assessment indicators to analyze the impact of COVID-19 on Chinese One Belt One Road (OBOR) ports. Design/methodology/approach: This study utilized a grey prediction model GM(1,1) to forecast five relevant indicators for each of the 17 OBOR ports both with and without COVID-19 background conditions. Additionally, the data envelopment analysis (DEA) efficiency assessment approach was used to analyze the impact of COVID-19 on port efficiency. Findings: The results indicate that cargo and container throughput growth rates during the COVID-19 pandemic are reduced by 1.7 and 2.1%, respectively. There was also a noticeable reduction in technological efficiency (TE) as well as pure technological efficiency (PTE), while scale efficiency (SE) remained largely unaffected. Furthermore, the dynamic efficiency MI was mainly negatively impacted by changes in overall efficiency change (EFFCH), where pure efficiency change (PECH) less than one contributed significantly towards overall regression of port efficiencies during this period. Originality/value: This paper is unique in its use of a combination of the grey prediction model and DEA efficiency assessment to quantify changes in important indicators during pandemic periods. This approach not only provides a quantitative understanding of the impact on port-level efficiency through numerical quantification but also offers readers an intuitive understanding. [ABSTRACT FROM AUTHOR]