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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]

Along with the temporal and spatial distribution characteristics, the toxicity equivalent of luminescent bacteria and the contribution of PAHs to the toxicity were evaluated. Figure 1 GLO:5JI/01nov22:etc5468-fig-0001.jpg PHOTO (COLOR): 1 In this composite image you can see the Three Gorges Dam in the Hubei Province, China, imaged by the Multi-Spectral Instrument (MSI) aboard the European Space Agency's Sentinel-2A satellite. Gas chromatography-mass spectrometry was used to determine the concentrations of 16 types of priority polycyclic aromatic hydrocarbons (PAHs) which were proposed by the United States Environmental Protection Agency. [Extracted from the article]

There has been a proliferation of new research discovery tools that aid scientists in finding relevant publications. To obtain a general overview of this development, this article generates a conceptual typology of all possible research discovery tools by drawing from the information-theoretical concepts of redundancy/variety. Bibliometric links between scholarly publications can thus exhibit 'redundancy' (i.e. expectable linkages between academic works) or 'variety' (i.e. original co-occurrence patterns). On the redundancy-reproducing end of the typology are machines that harness extant co-citations or keyword queries, such as academic search engines and paper recommender systems. The variety end of the spectrum harbours services that enable categorial browsing or that suggest publications randomly, such as journals' tables of contents or random paper bots. The typology has implications for understanding how the design of research discovery platforms may ultimately shape aggregate citational networks of science. [ABSTRACT FROM AUTHOR]

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]

Drawing on the business model innovation theory and the resilience theory, the present study explores existing literature on the capacity of digitalization and new technologies for the sustainable and innovative development of shipping and seaports; more in details, it identifies the shipping and seaport business models that can meet environmental, economic and social goals through the digitalization of operational processes in the ship–port interface. This paper aims to investigate whether digitalization and new technologies can help in the creation of sustainable business models as set out in the United Nations (UN) 2030 Agenda for Sustainable Development Goals (SDGs) adopted by all UN member states in 2015. The methodology is based on a qualitative approach, conducting a systematic literature review followed by a bibliometric analysis of a database containing 132 items in English language publications between 1969 and 2020. The findings indicate that literature on the topic has concentrated mainly on the environmental externalities connected with operations at the ship–port interface. The study offers theoretical and practical contributions, outlining the main issues debated in the literature on digitalization and new technologies in the shipping and seaport industry, and analyses the key variables that will play a role in achieving the SDGs. [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]

Seaports and their efficiency remain essential for the success of international trade globally. Notwithstanding this outcome, there is no empirical evidence on how seaport efficiency affect trade performance in Africa. This paper presents an empirical evidence of the effects of seaport efficiency on trade performance in Africa. To do so, we use data on 33 African countries for the period 2006 to 2018 and employ the gravity model for the empirical analysis. The results show that seaport efficiency enhances trade performance in Africa; the greater the level of seaport efficiency, the larger the extent of trade performance. Based on this finding, it is recommended that policy reforms that improve the efficiency of seaports in Africa should be targeted by policymakers. [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]

With customers looking for the highest level of services and reduction of cost on international trade of goods, shippers have recently begun to focus on the inland leg of containerized import/export, making the competition advance between 'seaport against seaport' to 'seaport-hinterland against seaport-hinterland'. Bearing this in mind, this paper seeks to assess the logistic costs and the import process time in order to identify how these factors influence seaport-hinterland customer's choice and what is the effect of these factors on the main actors' competitiveness. In terms of time, the findings indicate that dry ports have been operationally more efficient, with customs and delivery process faster than in seaports and extended gates. In terms of cost we have applied Monte-Carlo simulation in a case study in Brazil to assess stochastically the import cost considering multiple actors as options. The study makes practical contributions, showing the cost-efficient zone for each macro region in the studied area and simulating a hypothetical scenario, where multimodal transportation is a delivery option. Lastly, the study makes theoretical contributions, discussing the competitiveness environment in light of the literature, bringing relevant insights to aid customers' and practitioners decision-making. [ABSTRACT FROM AUTHOR]

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Purpose: This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies. Design/methodology/approach: This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context. Findings: The paper consolidates literature on strategy making in the context of extreme uncertainty in the seaport industry. Originality/value: The briefing saves busy executives, strategists, and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy-to-digest format. [ABSTRACT FROM AUTHOR]

Due to the constant risk of piracy and terrorist attacks which cause disturbances within international shipping of goods, barriers to the adoption of maritime security guidelines (MSGs) at European ports have become prevalent. In this paper, a conceptual framework was created to explore the perceived barriers that prevent compliance with MSGs. To verify the conceptual framework, empirical data were collected using a mixed-methods approach, which was comprised of interviews with national experts and a survey of 47% of Swedish ports involved in the shipping of goods. According to the presented framework, the perceived barriers of Swedish ports to compliance with MSGs were linked to collaborations within the Swedish Maritime Security stakeholder network, available resources and educational knowledge about security culture. In addition, the perceived barriers of smaller ports were linked to the adaptation to MSGs at different levels and the absence of specific tools of maritime security management. Due to an increased interest in international shipping of goods, this paper is currently one of few that addresses the barriers to compliance with MSGs. Moreover, the paper presents a general conceptual framework, novel managerial implications and recommendations for future research. [ABSTRACT FROM AUTHOR]

The paper searches the work process of a ship agent - providing a set of representation services and ensuring compliance with the interests of a vessel located in a sea port for the purpose of loading/discharging of cargo and/or for other purposes. Agents organize and coordinate the arrival, staying and departure of vessels from the seaport. In the paper, the agency service of ships in sea ports is presented as one consisting of three stages of the work of a ship agent - operations that are carried out before the arrival of the vessel in the port, during the stay of the vessel in the port and after her departure. The events that fixed the beginning and end of each stage are defined. The agency service process is rather complex due to the large number of third parties to be involved in the procedures and formalities that allow a vessel to arrive in the port and depart. Such a process is accompanied by the issuing of a number of documents that the agent must fill in in order to inform all interested parties. The main time of the vessels' stay in the port are cargo handling - loading and discharging operations. During this period, agency service includes non-stop control of cargo handling, considering the interests of the shipowner. The three stages of the process under consideration are formalized in their mutual dependence and mutual conditioning using the apparatus of temporal logic. Their clear coordination in time ensures the coordination of the process in general, because only the timeliness and correctness of each stage of the agency service process and its completion allow the next stage to begin. The presented process was formalized with the help of temporal logic operators, which can establish cause-and-effect relationships between the stages and ensure the continuity of the process and the interconnection of the stages themselves. A set of documents necessary for the start, execution and completion of each of the stages has been defined. Some of the documents are external to the ship agent, some are issued directly by him, but each of them is key in the implementation of certain operations in the process of agency service. [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 simulation modelling of shore- and sea-side port operations constitutes a fundamental prerequisite for effective project planning in port development, as the influence of numerous often interactive parameters has to be addressed at an early stage to account for the optimum supply of port facilities and services to current and future demand. This paper presents a detailed review of the available research literature on the application of simulation models in port development, through extensive reference to published journal papers from the onset of the relevant simulation modelling and through the course of the past 54 years (1961-2015). With focus on container terminals, this review aims at analysing the use of port related simulation models and ultimately at assessing their contribution into building the research knowledge necessary to promote sustainable ship-port interfaces and freight transport chains. It was found that over the past 50 years the use of simulation models has been increasingly favoured and instrumental in the development of ports and more specifically of container terminals. Most of the research literature addresses operational issues, accounting for its highest concentration and coherence in the research field of operations research, although the need to utilise the wide-ranging capabilities of simulation modelling in order to offer integrated solutions is recently promoting the dissemination of the relevant literature through sector-specific (i.e. transport and maritime) research fields. Finally, the observed tendency to employ simulation tools which offer the most realistic results reflects the research effort to ensure that simulation modelling offers tangible solutions to the maritime and transport industry. [ABSTRACT FROM AUTHOR]

Responding to the polarized view of artists either being displaced or co-opted in urban regeneration, this paper unveils a middle ground in which artists also act as partners or co-producers in these processes. We illustrate this intermediary role in property development processes with reference to a case study of the Seaport Innovation District in Boston by drawing upon a survey of resident artists and interviews with artists, planners, architects and economic development specialists. The paper makes two contributions to the literature. It offers a fresh look at the dialectical relationship between cultural and economic modes of production by more fully integrating consideration of artists’ sensibilities and practice with those of a host of built environment disciplinary practices including architects, planners and real estate developers. As a result, it extends extant analysis of urban regeneration-led gentrification from its urban planning, geography and sociology disciplinary roots into the disciplines of architecture and real estate. Our findings lead onto a research agenda centered on consideration of the intermediary roles played by creative and cultural sector actors and how creativity might be captured to positive effect, in the production of the built environment. [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]

Government institutions play a key role in advancing equity or perpetuating systemic inequities. As part of a long-standing journey, the Port of Seattle became the first port authority in the US to establish an Office of Equity, Diversity, and Inclusion (OEDI) in 2019. Since this milestone, the country has navigated not only a pandemic, but also a period of racial reckoning, which accelerated the Port's commitment and actions. This paper explores why the Port believes addressing equity and anti-racism is mission critical as a public sector institution and how doing so has the potential to have a positive impact on its mandate and outcomes. In addition, the paper explores three areas in which the Port has initiated systematic changes in efforts to embed equity in its operations and practices. [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]