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As a production division in a government-owned shipyard, the Commercial Ship Division has a direct workforce of 28% of PT PAL Indonesia's workforce. The revenue generated annually reaches 46% of the company's total revenue, with an increase in revenue reaching 50% each year. With the large number of direct labor, revenue targets and the complexity of the ship production process, workload analysis needs to be done to measure the workload of direct labor and the number of direct labor needed. Workload analysis is carried out using the Full Time Equivalent (FTE) method, where the FTE Index resulting from the calculation will be grouped into three categories namely underload, normal and overload. From the calculation of the FTE index of direct labor in the Commercial Ship Division, there are 5 people in the underload category, 27 people in the normal category and 134 people in the overload category. From the results of the calculation of direct labor requirements using the Full Time Equivalent method as well as optimization and efficiency of labor, the number of direct labor requirements for the Commercial Ship Division is 315 people. [ABSTRACT FROM AUTHOR]

The Kyrenia Ship, found off the north coast of Cyprus, is a key vessel in the history of scientific underwater excavations and in the history of Greek shipbuilding. The first volume of the site's final publication appeared in 2023 and provides detailed archaeological information tightly constraining the dating of the ship. A very specific date range is proposed: ca. 294–290 BCE, but is based on a less than certain reading of one coin recovered from the ship. While there is clear benefit to finding high-precision dates for the Kyrenia Ship and its rich assemblage using independent scientific dating (combined with Bayesian chronological modeling), efforts to do so proved more challenging and complex than initially anticipated. Strikingly, extensive radiocarbon dating on both wooden materials from the ship and on short-lived contents from the final use of the ship fail to offer dates using the IntCal20 calibration curve—the current Northern Hemisphere radiocarbon calibration curve at the time of writing—that correspond with the archaeological constraints. The issue rests with a segment of IntCal20 ca. 350–250 BCE reliant on legacy pre-AMS radiocarbon data. We therefore measured new known-age tree-ring samples 350–250 BCE, and, integrating another series of new known-age tree-ring data, we obtained a redefined and more accurate calibration record for the period 433–250 BCE. These new data permit a satisfactory dating solution for the ship and may even indicate a date that is a (very) few years more recent than current estimations. These new data in addition confirm and only very slightly modify the dating recently published for the Mazotos ship, another Greek merchant ship from the southern coast of Cyprus. Our work further investigated whether ship wood samples impregnated with a common preservative, polyethylene glycol (PEG), can be cleaned successfully, including a known-age test. [ABSTRACT FROM AUTHOR]

The paper studies a presynchronization control of grid connection for large merchant marine microgrid inverters. We present a virtual synchronous generator (VSG) algorithm with model-free adaptive control (MFAC) to optimize the stable grid connection of ship microgrid and shore-to-ship power. To solve poor precision of presynchronization control under nonideal ship microgrid condition, an MFAC controller and its presynchronization method are developed for grid connection of ship-distributed generation inverters. The proposed presynchronization control method effectively avoids a high transient overcurrent and achieves a seamless grid connection to different types of shore power. The simulation results verify the effectiveness of the proposed control method. [ABSTRACT FROM AUTHOR]

Ship pollution emissions have attracted increasing attention in the maritime field due to the massive growth of maritime traffic activities. It is important to identify the ship emissions (SEs) magnitude and corresponding spatial and temporal distributions for the purposes of developing appropriate strategies to mitigate environment pollution. The aim of this study was to estimate ship pollution emissions with various typical merchant ship types under different sailing conditions. We estimated the emission variation with a ship traffic emission assessment model (STEAM2), and then the ship pollution emission distribution was further visualized using ArcGIS. We collected data from the automatic identification system (AIS) for ships in New York Harbor and further analyzed the spatiotemporal distribution of pollutant emissions from ships. The experimental results demonstrate that the ship pollutant emission volume in the New York Harbor area in 2022 was 3340 t, while the pollution in terms of CO, SO2, CXHX, PM10, NOX, and PM2.5 was 136, 1421, 66, 185, 1384, and 148 t, respectively. The overall SEs from container ships, passenger ships, and tankers account for a large amount of pollution discharge. The pollutant emissions of container ships are significantly greater than that of their counterparts. Moreover, the spatiotemporal distributions of ship pollutant discharge can vary significantly among different ship types and sailing conditions. [ABSTRACT FROM AUTHOR]

An ocean acoustics experiment in 2017 near a shipping lane on the New England continental shelf in about 75 m of water provided an opportunity to evaluate a methodology to extract source signatures of merchant ships in a bottom-limited environment. The data of interest are the received acoustic levels during approximately 20 min time intervals centered at the closest position of approach (CPA) time for each channel on two 16-element vertical line arrays. At the CPA ranges, the received levels exhibit a frequency-dependent peak and null structure, which possesses information about the geophysical properties of the seabed, such as the porosity and sediment thickness, and the characterization of the source, such as an effective source depth. The modeled seabed is represented by two sediment layers, parameterized with the viscous grain shearing (VGS) model, which satisfies causality, over a fixed deep layered structure. Inferred estimates of the implicit source levels require averaging an error function over the full 20 min time intervals. Within the 200–700 Hz band, the Wales–Heitmeyer model captures the inferred frequency dependence of the source levels. [ABSTRACT FROM AUTHOR]

From a maritime-history perspective, little is still known about eighteenth-century Venice, especially in non-Italian literature. Classic interpretations of eighteenth-century Venetian shipping suggest that the Venetians never regained a significant role as carriers in the Mediterranean after the sixteenth century. Although Venetian shipping was heavily impacted by the arrival of the 'Northerners' in the Mediterranean at the end of the sixteenth century, its capacity for long-term recovery has yet to be clarified. The primary impediment to Venetian maritime activity was the high threat of attacks by the so-called 'Barbary corsairs' on their merchant ships, which drove up transport costs. The Republic of Venice signed treaties with Algiers, Morocco, Tripoli and Tunis from 1763 onwards, but historians remain sceptical about the effects of this peace. This article seeks to demonstrate that the treaties with the Barbary states represented a groundbreaking turning point for eighteenth-century Venetian shipping: from the 1760s onwards, liberated from the burden of high risks and high protection costs, Venetian shipping made a vigorous and lasting resurgence on all routes in the Mediterranean and beyond. Following the treaties, the Venetians became significant carriers in the Mediterranean sea trade and were able to rival other competitors in international markets. From this standpoint, the Venetian shipping sector not only recovered but also flourished until the ultimate dissolution of the Republic in 1797. [ABSTRACT FROM AUTHOR]

The complexities that attend global mobilities have shown us how migrants recreate home by drawing from their countries of emigration and immigration. In so many ways, any homemaking practices are embedded in home's mobile and sedentarist aspects. Amongst overseas Filipino workers (OFW), this means the performance of Filipino traditions like fiestas, and consumption of Filipino food whilst at the same time learning the language of their destination countries and partaking of their cultural and social practices. Filipino seafarers, however, present us with an interesting case: they perform homemaking practices within the constrained and limiting spaces of the ship where they both work and live. Filipino seafarers have a transportable home ready for unpacking and reconstruction on every ship that they board, drawing less on what the ship offers, but more on what reminds them of home back in the Philippines. Drawn from data gathered from more than a decade of engaging with seafarers on board ships and ashore, this article focuses on the homemaking practices of Filipino seafarers viewed as a means to meaning-making, where ships conceived as non-places could be turned into home, and seafarer wellbeing is specifically defined as self-preservation on board and continuing authority back home. [ABSTRACT FROM AUTHOR]

As part of the progressive process of extending spatial plans to cover an increasing number of marine areas, with the aim of objectively balancing the interests of various users of the marine area, it has become necessary to establish the value of marine areas as a yardstick or determinant of the user group for which a given marine area is of greater value. This study seeks to fill a research gap by attempting to develop a method to calculate the value of marine areas for the commercial shipping industry. This is done to make it possible in the future to prepare the ground for policy regulating the spatial rent of the sea, whose most important users are shipowners and their ships. We use the homogeneous basin of the Polish Marine Areas (PMA) in the Baltic Sea. Based on a literature review, we conclude that such a method does not exist, posing a significant challenge in the process of marine/maritime spatial planning (MSP) and maritime policy formulation. Conducting an in-depth analysis of 2020 data on ship traffic in the basin noted above, combined with a financial analysis of shipowners' operating costs and profitability indicators, we can determine the value of marine areas both in aggregate for all shipping in the studied basin and for each of the five segments of shipping -- the bulk cargo, ro-ro cargo, container, tanker, and passenger segments. In addition, through a dynamic analysis of ship traffic, it is possible to determine the value of sea area in Polish seawaters per unit of area (1 km²) at the average level and for the five specified market segments. The obtained values show that the total profits of shipowners in the Polish Marine Areas, which are at the level of more than EUR 103 million per year, and the average value of profits per 1 km² of marine area used by a ship provide future decision-makers with an objective point of reference to shape future policies for the fiscalization of public space, including the sea. [ABSTRACT FROM AUTHOR]

An employment of women-seafarers and related gender aspects are important in future development of modern shipping. At the same time, specification of maritime shipping imposes traditionally low proportion of women in relation to the total number of qualified seafarers on ships. Equality issues in maritime shipping are not only limited to equality between women and men, but also encompasses situations with vessel's operation issues and related working relationship. The purpose of this article is to define the tasks and trends of international legal provision of gender equality's improvement in practice plane on the basis of international law and current Ukraine's legislation, scientific developments, domestic and foreign experience. The UN Convention on the Elimination of All Forms of Discrimination against Women (1979) and the basic international legal instruments and agreements containing standards of equality between women and men offer member states a policy of eliminating discrimination and requiring the introduction of a range of antidiscrimination measures. International organizations such as the IMO and the ILO pay great attention to the importance of gender equality issues on merchant ships. One of the ILO's fundamental international standard is gender equality, which must be ensured by both of the state and the social partners, such as workers' and employers' organizations. Hence, ILO approaches in ensuring gender equality are very important in maritime shipping. Conducted research on gender equality, including equality between men and women in the merchant shipping industry, demonstrates a positive correlation in rights and achievements for women, in social, economic and political areas. [ABSTRACT FROM AUTHOR]

The article focuses on the discovery of the wreck of the Sydney Cove in the 1980s, leading to scholarly investigations into various aspects of the ship, its cargo, and crew. It mentions although historians have explored many facets of the wreck, there remains limited knowledge about the predominantly Indian crew known as Lascars.

• Ejector-compression ship refrigeration system for provision rooms designed. • Jacket cooling water of 85 to 95 °C is appropriate for ejector stage. • Two different-geometry ejectors apply to operate in variable seawater temperatures. • Ejector stage introduction contributes to 25–33 % fuel savings vs. standard system. • Ejector stage utilizing leads to 23.1–18.3 % CO 2 emission decrease vs. standard system. A novel combined ejector-compression refrigeration system for provision rooms of merchant ships was conceptualized and analyzed. The principle possibility of recovery of onboard low-grade heat (85–95 °С) of jacket cooling water was confirmed. Two ejectors of different geometries to ensure the ejector stage operation when the seawater temperature varies in a wide range were designed and proposed to install in parallel. The performance of the combined system was compared to a vapor-compression one and the choice of the rational temperatures in the condenser-evaporator t C/Ev was performed. The combined system COP total is considerably higher than the vapor-compression system, and it weakly depends on heat source temperature. At condensing temperature t C = 34 °С the decreasing in t C/Ev from 20/15 to 10/5 °С results in increasing of COP total up to 13.5 % at generation temperature t G = 80 °С and up to 15.6 % at t G = 90 °С. Utilizing the combined system for the onboard cold production will contribute to fuel savings of 25 to 33 % per voyage (operation and transport) vs. vapor-compression system. The combined system inherent the lower specific CO 2 emission per 1 kW h of cooling energy em refr than the standard system for all considered operation modes. The value of em refr for combined system at t C/Ev = 10/5 °C, t G = 80 °C and t C = 36 °C or t C = 42 °C is 23.1% or 18.3%, respectively, less than for the vapor-compression one. The approach to analysis proposed can be used for assessment of the feasibility of utilization of low-grade heat and the retrofit of ship refrigeration systems. [ABSTRACT FROM AUTHOR]

Many people embark and disembark on merchant ships to perform various duties while ships are moored in ports. Some units, such as marine pilots and coast guards, must board and disembark the ships while they are underway. Boarding and disembarking from ships include some dangers that could result in serious injury or even death. Regulations for pilot boarding arrangements have been developed by organizations such as IMO, ICS, and IMPA to reduce risks. At each Port State Control, Class, and P&I inspection, the condition of the pilot ladders and the accommodation ladders of the ships is inspected. The situation can be much more complicated and risky for boarding parties that have to board ships underway in extraordinary situations such as when pirates or terrorists had full control of the ship. Thus, there is a need for a model, which can identify the importance weightings for each contributing factor that is involved in boarding casualties. This study introduces a technique to identify risk factors for boarding parties through fuzzy Bayesian Networks (FBN). The findings of this research are expected to help boarding parties develop new strategies for their highly risky Opposed Boarding tasks. [ABSTRACT FROM AUTHOR]

Background: Merchant ships, despite huge technological progress, are still operated by qualified navigators. According to ergonomics principles, human is a part of the whole system and is affected by the surrounding environment. Objective: The purpose of the paper was to assess the ergonomic awareness of professional navigators, to understand their expectations towards navigation bridges and to check if they obtain enough support from their workplace. Methods: A special questionnaire was developed and 200 responses were obtained from seafarers with license of Officer Of the Watch or higher. Statistical analysis were carried out to find out relationships and differences between answers and groups of respondents. Results: Improper ergonomics and less than optimal working conditions were not isolated incidents and occurred to be rather common problem of the industry. The results suggest that ergonomic awareness is at relatively high level, however this knowledge is frequently not used in practice. Conclusions: Poor design and lack of proper ergonomics training might contribute to commonly experienced signs of fatigue, pain episodes and therefore reduced performance of seafarers. Navigators find ergonomics important, however navigation bridges often do not meet ergonomics and comfort standards, therefore there is still a room for improvement in this area. [ABSTRACT FROM AUTHOR]

Houthis’ recent attacks on Merchant ships in the Red Sea have renewed focus on maritime terrorism. These attacks have pushed the global power centres to think seriously about this intensifying threat to international maritime trade and movement. South Asia, particularly India and Pakistan, have already faced the issue of marine terrorism, yet it has remained primarily a neglected field of enquiry, particularly in Pakistan. This paper aims to fill this void in the literature by critically analysing the threat of Maritime terrorism to Pakistan and how prepared it is to counter this problem. This paper attempts to dissect the threats that exist in the Arabian Sea and how maritime terrorism has the potential to push Pakistan and India into a new conflict, which may have grave consequences for the global community. The paper starts with an overview of maritime terrorism and how it has evolved over time and with technological advancements. This follows an analysis of marine terrorism incidents in India and Pakistan and how Pakistan has built up its organisational structure to cover the threats posed by it. It contends that Pakistan has a ready organisational structure; it requires improved inter-departmental coordination and more importantly, constitutional cover. In the end, the paper provides policy recommendations at the organisational, national and regional levels to address the issue of maritime terrorism. [ABSTRACT FROM AUTHOR]

Digital 3D surveys of shipwrecks have become ubiquitous in recent years. As a substantial number of 3D shipwreck surveys accumulate, there remains a largely untapped opportunity for longitudinal and quantitative analyses of historic vessels in ways that were previously difficult or impossible using traditional methods, and which would provide new perspectives on the nautical archaeological record. A digital reference library was developed for Dutch ocean-going merchant vessels of the 17th and 18th century, including a substantial database of 3D scans of contemporary scale models, together with shipwreck scans, manuscripts, and other historical evidence. Important lessons for future typological digital reference libraries are highlighted, particularly the challenges of estimating scale, vessel classification and the need to publish survey data in open spatial formats. [ABSTRACT FROM AUTHOR]

Copyright of Mediterranea - Ricerche Storiche is the property of Mediterranea-Ricerche Storiche 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.)

Offshore wind farms have emerged as an effective method for responding to the energy crisis. However, offshore wind power generation has been indiscriminately planned at sea, leading to interference with the traffic routes of merchant ships. Many countries and organisations have set buffer zone standards to ensure the safe navigation of passing vessels, but these standards differ widely. As a typical example, the standards of the International Maritime Organization (IMO) and those of the Confederation of European Shipmasters' Associations (CESMA) are used to decide the route widths of vessels; however, they both have limitations, preventing their application to all sea areas. This study proposes a novel methodology to calculate the width of a route using distribution and line density analyses of 90% and 50% maritime traffic. First, four categorised maritime routes and gate lines are established to comparatively analyse the width of maritime traffic routes. Next, to ensure reliability-based route safety, the compliance of extracted maritime traffic route widths with the criteria established by the IMO and CESMA is verified. The selection of optimised widths for vessel traffic routes will ensure the safe navigation of maritime traffic and encourage the sustainable development of maritime spaces. [ABSTRACT FROM AUTHOR]

Education and training of seafarers are defined in the provisions of the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW Convention) and elaborated by the set of the International Maritime Organization (IMO) Model Courses. These documents represent minimum requirements for the education and training of seafarers at the international level. IMO member states shall integrate these requirements as appropriate into their maritime high school and college training programs and into training programs leading to STCW certification. Although there are different views in the literature and in practice about the existing seafarers training system, this system is standardized worldwide. This allows consistent acquisition of knowledge, skills, and competences for seafarers on merchant ships. The development and gradual introduction of autonomous ships raises numerous questions about the future trends of world shipping. Various researches are currently being conducted on autonomous ships. This technological progress brings with itself many challenges and one of them is the education of the personnel who will control and monitor these ships. It is clear that a new approach to seafarer's education needs to be developed. The development of this concept opens numerous questions from different segments of shipping and maritime security in general, particularly in the context of maritime cyber security. The paper analyses the education concept for seafarers in the Republic of Croatia, paying special attention to trends related to the development and deployment of Maritime Autonomous Surface Ship (MASS). [ABSTRACT FROM AUTHOR]

The document "Autonomous Ship Activities in Norway" provides an overview of the Norwegian Forum for Autonomous Ships (NFAS) and the development of autonomous ship technology in Norway. Norway, with its strong maritime industry, is a leader in this field, with projects such as the Yara Birkeland and automated truck ferries. The prevailing opinion in Norway is that autonomous ships will be assisted by remote operations centers (ROCs) in complex situations. The text also explores potential markets for autonomous ships, including autonomous ferries in small communities and a hub-and-spoke transport system. While there are challenges in regulation and approval processes, there are ongoing developments to address these issues. [Extracted from the article]

The impact of fuel consumption on merchant ships is categorized in both economic and environmental ways in terms of sustainable blue growth. Apart from the economic benefits of reducing fuel consumption, attention should be paid to related environmental concerns with ship fuels. As a result of global regulations and agreements concerning mitigating greenhouse gases on board, such as the International Maritime Organization and Paris Agreement, ships have to take a step to reduce fuel consumption to adopt these regulations. The present study aims to determine optimal speed diversity depending on ships' cargo amounts and wind-sea states to reduce fuel consumption. Within this context, one-year voyage data from two model sister Ro–Ro cargo ships were used, including daily ship speed, daily fuel consumption, ballast water consumption, total ship cargo consumption, sea state, and wind state. The genetic algorithm method was used to determine the optimal diversity rate. In conclusion, after speed optimization, optimum speed result values are calculated between 16.59 and 17.29 knots; thus, approximately 18% of exhaust gas emissions were also reduced. [ABSTRACT FROM AUTHOR]

Mobbing is a fundamental problem that disrupts the organization's structure and negatively affects its employees' safe work environment. The most critical issue in combating mobbing is increasing the awareness of victims, businesses and society about this problem. The importance of identifying this problem, which will adversely affect the professional life in the maritime profession, as in every professional group, is obvious. This study offers a statistical analysis-based dynamic Bayesian network to model seafarers' mobbing acts in merchant ships. In this research, measures against mobbing in the maritime industry are also recommended after determining the most frequent mobbing elements in ships. It is observed that the seafarers who have just stepped into onboard are more exposed to mobbing; in contrast, mobbing attacks experienced by seafarers decrease with an increase in age. The most frequent mobbing behaviours are listed as: "I am continually given new tasks", "My superiors restrict the opportunity for me to express myself" and "Unfounded rumours about me is circulated in the ship". The study reveals that while the maritime authorities such as PSC and the ITF have limited capabilities for solving mobbing related problems, the companies may have a crucial role to play in the process. [ABSTRACT FROM AUTHOR]

This article aims to discuss the development of shipping activities at Port Swettenham from 1901 to 1919. Port Swettenham was developed with the aim of making this port the main port not only for Selangor, but also for the Federated Malay States (FMS). Accordance with that, the objective of this study is to analyse the development of shipping activities at Port Swettenham which is a benchmark for the needs of this port to be developed. This study uses a qualitative methodology based on archival and library research with reference to Reports on the Marine Department of the State of Selangor as the main source alongside the Selangor Administration Report and Reports for the Klang Districts. The results of the study found that the development of Port Swettenham is important to Selangor and FMS as the main port and a link for the export of tin and rubber which became the main commodity around the 20th century, especially when the First World War broke out. Although the development of Port Swettenham was not supported by most shipping companies, but Port Swettenham has grown rapidly and not only handled coastal merchant ships and small-sized ships, but also received the arrival of large-sized ocean-going merchant ships starting in 1904. Therefore, the development of shipping activities at Port Swettenham has shown that this port really needs to be developed to accommodate the development of trade in the FMS and reduce dependence on the ports of the Straits Settlements (SS). [ABSTRACT FROM AUTHOR]

The recognition of ice channels plays a crucial role in developing intelligent ship navigation systems in ice-covered waters. Navigating through ice channels with the assistance of icebreakers is a common operation for merchant ships. Maneuvering within such narrow channels presents a significant challenge for the captain's skills and ship performance. Therefore, it becomes essential to explore methods for enabling ships to navigate through these channels automatically. A key step in achieving this is the accurate recognition and extraction of boundary lines on both sides of the ice channel. An ice channel line recognition method based on the lane line detection algorithm UFAST is implemented. The method is trained and tested on the constructed ice channel dataset, with the test results showing that the average recognition accuracy reaches 84.1% and the recognition speed reaches 138.3 frames per second, meeting the real-time requirement. In order to solve the current lack of authentic ice channel images, ice channel navigation scenes are built based on UE4, and synthetic ice channel images are rendered. The method in this paper is also compared with the traditional non-intelligent Otsu threshold segmentation method and the intelligent instance segmentation method YOLACT for performance analysis. The method in this paper has 9.5% higher ice channel recognition accuracy and 103.7 frames per second higher recognition speed compared with YOLACT. Furthermore, ablation studies are conducted to analyze the relationship between the number of gridding cells in the proposed method and ice channel recognition accuracy. [ABSTRACT FROM AUTHOR]

The decreasing of Arctic sea ice is projected to continue with global warming, which makes the summer navigation conditions of the Arctic improve. Based on the multi-source remote-sensing data with inter-sensor calibration processing and the ship-based observational data from R/V Xuelong and M/V Yongsheng, the sea ice conditions of the Arctic Northeast Passage (NEP) during the 2002–2021 summer seasons were analyzed, and the navigability of the NEP between July and October from 2002 to 2021 was discussed. Inter-sensor calibration could effectively reduce the deviation from different passive microwave data. Sea ice extent and thickness in the NEP decreased annually, which resulted in the navigability of the NEP showing a potential tendency toward improvement in navigability. The navigation period was mainly concentrated in early August to early October. The middle part of the NEP was primarily affected by sea ice. This influence decreased over time, while the navigation period increased, especially in the Vilkitsky Strait, which is a key shipping area. This analysis of sea ice conditions and navigability in the past 20 years could provide a reference for future scientific investigations and aid in merchant ship navigation in the Arctic summer. [ABSTRACT FROM AUTHOR]

Ships unintentionally radiate underwater noise mainly due to propeller cavitation under usual operations. In 2022, the International Maritime Organization started a review of the nonmandatory guidelines for the reduction of underwater radiated noise (URN) from ships. The characteristics of URN from ships have been studied for a long time, and quantitative variations in URN levels with ship size and speed have been reported. From the viewpoint of ship design, it is more reasonable that the effect of ship speed and draft is considered as the ratio to design speed and maximum draft, respectively. Therefore, in this study, underwater sound measurements were conducted in deep water (>300 m in depth) under a sea lane, and regression analysis was applied to the source levels of the URN from many merchant ships using ship length, ship speed ratio to design speed, and draft ratio to maximum draft. In this analysis, the source level is simplified based on the characteristics of URN due to propeller cavitation. This allows one coefficient to represent the approximate shape of the spectrum of URN level. Further, variations in the URN level for each ship type are discussed based on the results and comparisons with previous studies. [ABSTRACT FROM AUTHOR]

Douglass North's work on the productivity of early modern British merchant shipping, along with that of his students Gary Walton and James Shepherd, taught us much about how the economy of British America worked. While crediting the security of the seas and more efficient business organization for allowing modest growth in shipping productivity, they relegated technological adaptation to insignificance. While accepting the main thrust of their argument, and indeed furthering it, John McCusker, Russell Menard, Nathan Rosenberg and Frederic Lane declined to dismiss the role that such adaptation might have played, leaving open the possibility that ship technology was worth exploring in a time and place for which it was generally considered static. Phillip Reid's exploration of that subject has been guided by two premises: first, that continuity as well as change can serve as technological adaptation to operating conditions; and, second, that economic maritime history has paid too little attention to the technology of the ordinary merchant ship in this period to evaluate its contribution to the success of the shipping industry – or lack thereof. Both continuity and change served as technological adaptations, allowing the merchant ship to serve a shipping industry that, in turn, served a world growing and changing demographically and economically, with that change accelerating in the second half of the eighteenth century. In past work, he has argued that specific continuities and changes in the merchant ship are best explained as strategies of 'risk mitigation'. Here, he also considers the distinction between risk and uncertainty to determine what, if any, application it might have to understanding continuity and change in the hazards to profit presented by the ever-present and dangerous collection of hazards posed to the merchant ship and crew by the Atlantic and the human predators who cruised it. [ABSTRACT FROM AUTHOR]

This paper describes how uncontrolled and illegal mining of sand and gravel can affect surface water and groundwater regimes in places where there is a hydraulic connection between them, based on a case study of the Velika Morava River in Serbia. Also, a change in cross-profile geometry, as a result of anthropogenic and natural factors, hinders the preparation of this river for inclusion among Serbia's waterways. The Velika Morava River's navigability would enable the development of waterborne transportation for both merchant ships and vessels of the Serbian Armed Forces River Flotilla. Correlations between water levels at gauging stations, as well as correlations between groundwater levels and river water levels at gauging stations, are used to show the dependence of these parameters on the change in the river bed profile after sand and gravel mining at the locations near gauging stations. In addition, the homogeneity of time-series of average annual elevations and the variance of the water levels of the Velika Morava River, measured in gauging stations during different periods, are statistically analyzed. The deepening of the Velika Morava riverbed where it was indiscriminately excavated in the 1980s led to the disruption of the groundwater regime and the hydraulic connection with the river, which lowered the water table of the aquifer used for the public water supply, as well as causing a number of other negative consequences. [ABSTRACT FROM AUTHOR]

Seafarers working on ships on international voyages have to work in closed environments away from their families and social life, and are socially isolated. In other words, seafarers work in environments in which all vital workplace activities take place together, and the possibility of socialization is very limited. In this regard, the purpose of this study is to examine the indirect effect of perceived organizational support on subjective well-being through psychological resilience and the moderator role of job stress in this interaction by seafarers on merchant ships operating internationally. Data were obtained from 408 seafarers by questionnaire technique. Mediation, moderator, and moderated mediation analyses were performed using Hayes Process Macro. The results show that psychological resilience has a mediation variable role in the relationship between organizational support perception and subjective well-being, but the mediation role of psychological resilience does not change by the level of job stress. This study is the first of its kind to holistically evaluate the relationship between these variables and with a specific focus on seafarers, it offers valuable suggestions to shipping businesses and researchers interested, thus making a significant contribution to the relevant literature. [ABSTRACT FROM AUTHOR]

Copyright of Art-Sanat Journal / Art-Sanat is the property of Art-Sanat 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.)