New Building Research Articles

Optimization of honeycomb parameters of sandwich composites for energy and specific energy absorption using particle swarm optimization

Sandwich composites are special class of materials because of peculiar properties such as lightweight, high damping and high energy absorbing capacity etc. These properties make them suitable for their use in the shipbuilding and aerospace industry. Honeycomb structures are commonly used core materials in the sandwich composites. The elastic properties of honeycomb are characterized by foil thickness (FT) and cell size (CS) therefore they have significant effect on the mechanical properties. In this manuscript, low velocity impact analysis has been carried out on couple of aluminium honeycomb sandwich composites using Charpy ASTM E−23 machine and the energy absorbed by the sandwich specimens has been recorded. These experimental results have been validated through the numerical simulations carried out using commercially available software Abaqus. The results are found to be in good agreement. The parametric study also has been carried out to investigate the effect of foil thickness (FT), cell size (CS) and core height (CH) on specific energy absorption. Further, sufficient number of samples have been generated from latin hypercube samples (LHS) design and analyzed using Abaqus. Based on these results, polynomial equations have been generated in order to establish the relation between energy dependent variables (Energy absorption and Specific energy absorption(SEA)) and independent variables (Foil Thickness(FT) and Cell size(CS)). These polynomial equations have been used as fitness functions in optimization. The optimization process has been carried out by particle swarm optimization (PSO) matlab code for energy and specific energy absorption.

Robust pose estimation for ship block assembly feature based on large-scale scanning

PurposeHull block assembly is a vital task in ship construction. It is necessary to obtain the actual poses of the assembly features to guide further block alignment. Traditional methods use single-point measurement, which is time-consuming and may lead to loss of key information. Thus, large-scale scanning is introduced for data acquisition, and this paper aims to provide a precise and robust method for retrieving poses based on point set registration.Design/methodology/approachThe main problem of point registration is to find the correct transformation between the model and the scene. In this paper, a vote framework based on a new point pair feature is used to calculate the transformation. First, a special edge indicator for multiplate objects is proposed to determine the edges. Subsequently, pair features with an edge description are noted for every point. Finally, a voting scheme based on agglomerative clustering is implemented to determine the optimal transformation.FindingsThe proposed method not only improves registration efficiency but also maintains high accuracy compared to several commonly used approaches. In particular, for objects composed of plates, the results of pose estimation are more promising because of the compact pair feature. The multiple ship longitudinal localization experiment validates the effectiveness in real scan applications.Originality/valueThe proposed edge description performs a better detection for the edges of multiplate objects. The pair feature incorporating the edge indicator is more discriminative than the original template, resulting in better robustness to outliers, noise and occlusions.

Variation Propagation Analysis of Hull Flat Block Construction Process Based on State Space Model

_ Hull flat block (HFB) construction is a typical discrete manufacturing process, during which block deviation is accumulated. To satisfy the dimensional requirements of shipowners, the variation propagation during HFB construction must be modeled and analyzed. Based on the stream of variation theory, the construction process is analyzed to provide a reference for controlling the deviation. In the hull construction process, the deviation is categorized into part deviation, location deviation, and welding deviation. By analyzing the causes of the different deviations, the different deviations and their accumulations can be calculated. A HFB is used to verify the proposed model, and the results show that the method can be used to calculate the deviation to the HFB. Introduction As a typical large-scale complex equipment, the hull construction process is extremely time-consuming and laborious. The final hull is composed of intermediate products, such as subassemblies, unit assemblies, and grand-assemblies (Cho et al. 1999). Since the group technology was applied in hull construction, a series of production lines has been established based on the process similarity of parts, components, blocks, and grand blocks. The actual dimension of parts would inevitably deviate from the theoretical dimension (Mandal 2017), i.e., dimensional and shape deviations will occur owing to many factors (Okumoto 2002). In the hull construction process, the deviation from the previous process will be propagated to the current process and coupled with the deviation in the current process, thereby affecting the accuracy of the product. Hence, the product must be repaired to satisfy the design requirements (Takechi et al. 1998). This will prolong the production cycle and reduce the production efficiency (Heo et al. 2015). It was discovered that the man-hours of the main operations during hull assembly constituted only one-sixth of the total assembly manhours, whereas the man-hours used for adjustment constituted one-third (Chen et al. 2020). Currently, shipyards need to eliminate the adjustment operation to avoid unnecessary rework, as well as reduce human and material resources in subsequent processes. Tanigawa (2003) estimated that an ideal ship construction accuracy control plan can reduce the production cost by 5%. Therefore, the accuracy of the hull construction process must be controlled and improved in shipyards, and a reasonable accuracy control plan should be devised to improve the product quality.

Energy efficiency and decarbonization for container fleet in international shipping based on IMO regulatory frameworks: A case study for South Korea

ABSTRACT This study investigates the impact and potential of ship’s energy efficiency and decarbonization in Korean container shipping following the IMO regulatory framework. The IMO started implementing the EEXI (Energy Efficiency eXisting-ship Index) and CII (Carbon Intensity Indicator) regulations for the existing vessels on 1 November 2022. The government of South Korea announced a national plan called “the 2030 Greenship-K initiative” to boost the shipbuilding and shipping industries. This plan describes 140 merchant vessels with green ship technologies that will be required for sustainable shipping. The Korean container fleet needs to examine the impact of the IMO regulations through eco-friendly technologies like engine power limitation, energy-saving devices, alternative maritime fuels, etc. It is necessary to select an eco-friendly technology based on the marginal abatement cost for the fleet. Five case studies are considered on which alternative is beneficial for ship decarbonization. The most favorable alternative seems to be an LNG fuel retrofit for the EEXI and CII regulations for the Korean container fleet.

Influence of aging heat treatment at 180 °C on cavitation erosion for aluminum alloy type 5083 in cold rolled state

Aluminum-based alloys have wide applicability in the construction of aircraft, vehicles, and ships. Some of their components, during operation, such as the radiators and the rotors of the cooling pumps in the vehicles, and the propellers of fishing and pleasure boats are affected by the abrasive, chemical and cavitational corrosive action of the water. At certain hydrodynamic flow regimes, the most dangerous becomes the corrosion through cavitation. Operation in such regimes inevitably leads to damaging the structure, due to cyclic stresses of the micro-jets and shock waves generated by the implosion of cavitation bubbles. Although the chemical constitution and alloying with other chemical elements increase the mechanical properties, the service life is still limited when operating in high-intensity cavitation flows. Therefore, researchers are looking for solutions to improve this resistance through various treatments, such as bulk heat. Research heading the same direction, but, made on 5083 alloy, is presented in this paper. The results highlight the behavior of a modified structure compared to the semi-fabricated state (obtained by rolling), through three durations regimes (one hours, 12 hours and 24 hours) of aging heat treatment to 180 °C temperature, after hardening treatment at 450 °C. The cavitation tests were performed in the Laboratory of the Polytechnic University of Timisoara, on the standard vibrating device with piezoceramic crystals. The results were expressed by curves and parameters specific to the evaluation of cavitation resistance, and by macro and microscopic images, showing the unique aspects of the connection between the structure and the mechanical properties obtained through heat treatment regimes. Thus, comparison of the results, including with the delivery state (laminated product), shows that the highest resistance is provided by the treatment at 24 hours. At the same time, the erosion, of pitting and caverns type, and differs from one structure to another.

Cancro Renal associado ao Trabalho

Introduction/framework/objectives There are several cancers that can be associated with some characteristics of the Work. Regarding the oncological pathology of the Kidney, there are not many publications. The aim of this review was to summarize what has been reported on the subject to date, in order to enhance the performance of Occupational Health and Safety Teams working in possibly targeted sectors. Methodology This is a Bibliographic Review, initiated through a search carried out in January 2022 in the databases “CINALH plus with full text, Medline with full text, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Cochrane Methodology Register, Nursing and Allied Health Collection: comprehensive, MedicLatina and RCAAP”. Content Kidney Cancer, at the level of non-occupational etiology, may be associated with tobacco, obesity and high blood pressure (metabolic syndrome), as well as Cystic Kidney Disease, male gender, older age, black ethnicity and family history. It is believed that tobacco can explain 20 to 30% of it in men and 10 to 20% in women; being the dose-dependent relationship. The association with arterial hypertension also seems to be dose-dependent and more intense above 160 and 100 mmHg for systolic and diastolic, respectively. There are several working conditions capable of enhancing it; even so, studies sometimes do not consider the possible influence of biasing variables, such as smoking, including passive. Discussion and Conclusions Although without absolute consensus, this cancer seems to be enhanced by exposure to Radon/Uranium, Asbestos, Pesticides, derivatives of Fuels and various Chemical Agents (such as tri and tetrachlorethylene, dinitrotoluene and lead). Thus, the most targeted professional sectors could be mining; civil and naval construction, demolition sector; agriculture; production, packaging and distribution of relevant chemical agents; refineries and filling stations; as well as dry cleaning, printing, car and aircraft mechanics, maintenance, metallurgy, drivers and road pavers. It would be pertinent for some Occupational Health and Safety teams to initiate research projects in this context, for subsequent dissemination of conclusions, in order to advance knowledge and provide a healthier and safer work environment. KEYWORDS: kidney cancer, occupational health, occupational medicine and safety at work.

A Literature Review on Fabrication of Portable Spot Welding Machine

Abstract: Welding is a process of joining similar metals by the application of heat. Welding can be done with or without the application of pressure. While welding, the edges of metal pieces are either melted or brought to plastic condition. Welding can be done with the addition of filler materials or without it welding is used for making permanent joints. It is used in the manufacture of automobile bodies, aircraft frames, railways wagons, machine frames, structural work, tanks, furniture, boilers, general repair work and ship building. At most in all metal working industries welding is used. In this project we are making portable spot welding machine , which will be easy carry and will be used in many filed.

Hardness Analysis of Aluminium 5083 A-TIG Welding Due to The Effect of Active Flux and Current

Aluminium allow has been widely used recently due to their high strength to mass ratio, good formability and high corrosion resistance have a wide range of applications in aerospace, ship-building and railway industries. The 5083 series aluminum is the most widely used due to good strength and corrosion resistance properties. Tungsten Inert Gas Welding (TIG welding) is the most common welding method for aluminum alloys. This research was conducted A-TIG welding on 150 x 100 x 8 mm of 5083 aluminium and added by oxide powder (MgCl2 and TiO2) as active flux and various of current consist of 100, 130, and 160 A. The result of this research was obtained that the deepest penetration was 4.94 mm with TiO2 active flux and the current of 160 A, the highest hardness came from weld metal which using MgCl2 as an active flux with 100 A of current with 69.80 HVN. The hardness was increased by adding magnesium due to effect of it could be increased grain coarse. The lowest hardness was on weld metal with TiO2 active flux with 160 A of current due to the maximum heat input which decreased the hardness The recrystallization was occurred due to increase of heat input, so did the grain growth. The coarse grain which caused the decreasing of hardness was affected by the increase of heat input.

Optimizing Traditional Shipyard Industry: Enhancing Manufacturing Cycle Efficiency for Enhanced Production Process Performance

The traditional shipbuilding industry is crucial in the global maritime sector, contributing to ship construction, repair, and maintenance. However, it faces challenges in improving production process efficiency. This article explores strategies to optimize the industry's manufacturing cycle. A comprehensive literature review identified key challenges, including production planning errors, coordination issues, material delivery delays, and limited technology integration. These challenges result in higher costs, reduced productivity, and project delays. To address these issues, the article proposes integrating efficient management systems like Lean Manufacturing and Total Quality Management to enhance the production cycle's efficiency. Implementing these systems eliminates non-value-added activities, simplifies processes, and reduces wait times. Additionally, the Manufacturing Cycle Efficiency method is valuable for analyzing production processes, identifying waste, bottlenecks, and interruptions, and optimizing workflows. In conclusion, this article provides insights and strategies to optimize the traditional shipbuilding industry. By integrating efficient management systems, utilizing the MCE method, and embracing sustainability practices, shipyards can enhance production cycle efficiency, increase productivity, and gain a competitive advantage, supporting industry growth and paving the way for a sustainable future.

Ship technology, slavery, repatriation and air transportation: continuity and change

The Trans-Atlantic Slave Trade, which occurred between the fifteenth and nineteenth centuries, displaced Africans and people of African descent into the New World. The trade affected and influenced several aspects of the world economy, boosting the economies of participating countries and creating what would become the African diaspora. While several elements of the trade have gained recognition in scholarship, ships, as the single most important medium of transportation for African slaves, have received little attention. We contribute to the discourse by placing ships at the center of discussion by highlighting the relevance and importance of this human and cargo carriage as a vehicle of slavery. We also paid attention to air transportation in the era of voluntary repatriation of people of African descent back to Africa for tourism, business and to pay homage to the motherland. We achieved these objectives through the use of written sources. These included books, journal articles and relevant sites and databases relating to the history of science, technology and slavery among others. The research highlights, among others, the following: the invention of ships has changed the course of world history. It has been the single most tremendous medium of transportation responsible for transporting millions of Africans into Europe and the New World creating the African Diaspora. The era of sailing and the cruise period have offered man the opportunity to navigate oceans and seas that were hitherto uncharted. It also ensured that trade relations between and among countries were solidified. Beginning in the XIV century when ships used rudders that ran on shallow waters, trade was organized on as small scale between countries. The fifteenth century became a significant date in the history of ship building as there was an improvement in sea faring and oceanic navigation. The double-ended ship gave way for full-rigged ships. An even greater milestone was achieved in the eighteenth century when the steam was invented. This period produced fast sailing ships which were less costly and it greatly influenced the triangular trade which had begun some two centuries earlier.

Potential Development Strategy for the Shipbuilding and Ship Repair in Baltics

This research is focused on the shipbuilding and ship repair industries in Latvia. The main purpose of this manuscript is to investigate all possible options to further develop the shipbuilding and ship repair industries in Latvia Initially, a brief overview of Baltics and of Latvia, with its biggest shipbuilding companies and its possibilities, are depicted in detail. The analysis is developed with the help of SWOT analysis and a Risk assessment matrix to find Latvia’s strengths, weaknesses, opportunities, and threats, then to identify all possible risks in order to identify potential issues that could negatively impact key business initiatives or critical projects, and to develop a marketing strategy. It is concluded that Latvian shipbuilding can be benefited by i) its strategic location in Baltics, ii) the highly qualified workforce employed in Latvian shipyards, iii) the certified naval expertise of the shipbuilding facilities. At the same time, the external environment and the regional competition is harsh and some points are suggested for Latvian shipbuilding to survive and possibly flourish over the next years, such as: i) repair the technologically obsolete equipment and facilities to be able to satisfy the present market trends, ii) incorporate and utilize new materials and technologies, iii) give incentives to qualified natives that went abroad for employment to similar facilities to return to Latvia and utilize their accumulated experience, thus solving the issue of the declining workforce on the sector and iv) specialize in some aspects of shipbuilding, such as luxury ships and ice class, to secure a more specialised and dedicated market.

Mechanical Properties Evaluation of Laminated Composites of Petung Bamboo (Dendrocalamus asper) and Coconut Coir Fiber as Ship Construction Components

The high demand for steel and wood as the primary shipbuilding materials will increase market prices due to decreasing supplies each year. To address this issue, new alternative materials that are more environmentally friendly and inexpensive, such as natural fibers like bamboo and coconut fiber, must be explored. This study aimed to investigate how the directional arrangement (0° unidirectional and 90° unidirectional) of laminated Petung bamboo (Dendrocalamus asper) affects the compressive and flexural strength of ship construction. The compressive strength on the X, Y, and Z-axis was measured to determine the laminated beam’s strength ratio on each side. In contrast, the flexural strength was only observed on the Y and Z-axis due to testing equipment limitations. The results showed that the directional arrangement of laminated Petung bamboo with different test axes significantly impacted the compressive and flexural strength of laminated beams made of Petung bamboo and coconut coir fiber. Laminated Petung bamboo and coconut coir fiber with 0° unidirectional fiber had better compressive and flexural strength values than those with 90° unidirectional fiber. Based on the data testing, the combination of Petung bamboo and coconut coir fiber materials can be categorized into different strength classes. These findings have important implications for using laminated bamboo in shipbuilding applications. The use of laminated bamboo with a 0° lamina direction could be recommended for ship components that require high levels of strength than laminated bamboo with a 90° lamina direction.

A Study on the Historical Process of Concrete Ships in Terms of Shipbuilding Industry

Gemi inşaatı sektöründe, günümüze kadar birçok malzeme çeşidi gemi gövdesi yapısında kullanılmaktadır. En çok bilinen gemi inşa malzemeleri çelik, alüminyum alaşımları, elyaf destekli kompozit ürünler ile birlikte ahşap malzemelerdir. Bu çalışmada en çok bilinen inşa malzemelerin aksine betonun gemi gövdesinin inşasında kullanıldığı periyotlar özellikle askeri uygulamalarda nedenleriyle birlikte incelenmektedir. Tarihçesi 1848 yıllarına kadar dayanan beton gemiler kargo gemisi, yüzer barç, yat, balıkçı tekneleri olmak üzere birçok alanda işletilmiştir. Çelik tedarikinin zor ve maliyetli olduğu, nitelikli iş gücü ihtiyacının tam olarak karşılanamadığı özellikle birinci ve ikinci dünya savaşı döneminde oldukça büyük ölçekli beton gemiler inşa edilmiş fakat bu gemilerin hiçbiri operasyonel faaliyetlerini günümüze kadar sürdürememiştir. Genellikle inşa edildikten kısa bir süre sonra ana amaçlarının dışında eğitim gemisi, depo veya dalga kıran olarak kullanılmış veya batırılmıştır. Bu çalışma beton gemiler ile ilgili tarihsel gelişimi ham çelik üretimini de göz önünde bulundurarak incelemekte aynı zamanda süreç boyunca beton gemilerle ilgili yaşan olumsuzlukları, gemilerin son durumu ile ilgili literatüre katı sunmayı amaçlamaktadır. Ayrıca literatürde oldukça az değinilen bu alana katkı sağlayarak, bu alanda çalışacak akademisyenler, uzmanlar ve denizcilik paydaşları için önemli bir kaynak oluşturmayı hedeflemektedir.

Determination of Indicators of Implementation of Sea Transportation Safety Management System for Traditional Shipping Based on Delphi Approach

The implementation of the safety management system (SMS) in traditional shipping in Indonesia, known as “Pelra”, has not been implemented. The nature of the operation pattern and characteristics of Pelra, which are still traditional (non-convention), means that international maritime rules such as SOLAS, MARPOL, LLC, Collreg, and STCW, as well as Indonesian government regulations related to shipping safety, are not suitable for Pelra. As a result, Pelra ship accidents continue to occur every year in Indonesian waters without any efforts to deal with safety management. The aim of this study is to find indicators to assess the implementation of Pelra’s SMS that adopt the specific characteristics of Pelra sea transportation. The analysis was conducted with a Delphi approach, based on expert opinion in the field of ship safety, which was tested using non-parametric statistics (Kendall’s W test). The consensus results obtained 9 factors described in 44 assessment indicators to implement SMS on Pelra vessels. Several new indicators were found, including indicators related to ship stability, ship construction, and safety and navigation equipment. The level of expert agreement from the concordance W coefficient value is in the range of 0.3 (moderately strong) to 0.7 (very strong), which suggests that these findings are valid and feasible to be used as assessment indicators in order to implement SMS Pelra.

Reducing CO2 Emissions during the Operation of Unmanned Transport Vessels with Diesel Engines

Environmental protection is one of the most challenging tasks facing mankind. Reducing CO2 emissions in the global economy, including maritime transport, is being pursued in various ways, one of them being the design work leading to the construction and operation of unmanned ships. Unmanned vessels operating on longer routes will still have internal combustion propulsion. However, they will not have the superstructure and the various systems and equipment necessary for the crew. This will result in an unmanned vessel having less weight, less displacement and, therefore, less size, resistance and propulsion power than a manned vessel for the same transport capacity. Consequently, the unmanned vessel will emit less CO2. This paper presents a novel method for predicting fuel consumption and CO2 emissions for unmanned container ships. The method uses regression relationships of geometric and operational parameters for manned container ships developed for this purpose to determine such relationships for unmanned ships. On this basis, it is shown what the level of CO2 reduction will be compared to manned container ships.

AN SE BASED MARITIME VESSEL DEVELOPMENT FRAMEWORK FOR CHANGEABLE PROPULSION SYSTEMS

AbstractReducing Greenhouse Gas Emissions from vessels is one of the greatest challenges the maritime industry is currently facing. International Maritime Organization has set the goal of reducing CO2 emissions from international shipping by at least 40% by 2030, compared to 2008. Emissions regulations are also leading to a progressive reduction of ships life span, together with a decrease in economic value. To cope with these challenges, the preferred strategy suggested by IMO for new vessels -Energy Efficiency Design Index- aims at increasing the energy efficiency over time by stimulating innovation and continuous development of technical elements. In this context, ship builders are indirectly led to develop vessels that will be “changeable” in terms of propulsion systems over time. This paper presents a conceptual framework to maritime vessels for propulsion system changeability, which integrates contributions from literature review with the knowledge of design thinking experts and precious insights of maritime industry professionals. The aim of this framework is support the integration of renewable fuel sources for vessel propulsion systems through an extended value approach, while improving propulsion efficiency over time.

Effect of Air Humidity in MIG Welded Joints on Tensile Strength and Impact Strength of Aluminum 5052

In the shipbuilding process, delays often occur. In general, to speed up a ship's construction, overtime is carried out by workers until nighttime. Environmental conditions in a welding process, especially air humidity, strongly affect the properties of welded joints. The formation of hydrogen in the air caused by an inappropriate environment can cause defects in welded joints, especially porosity defects. Variations of welding environmental conditions used, are welding in the morning at 84% air humidity, daytime welding at 53% air humidity, and nighttime welding at 77% air humidity. This study aims to determine the material strength of air humidity variations during the welding process on the tensile strength and impact strength of 5052 aluminum material. This research uses experimental quantitative methods data analysis techniques used analysis of variance (ANOVA). The results showed that the higher the air humidity, the tensile and impact strength decreased. From the results of the tensile test, there is an influence of air humidity on the average value of tensile strength, where the highest value is found in the daytime welding variation specimen with 53% air humidity, worth 110.614 MPa. From the impact test results, there is an influence of air humidity on the average value of impact toughness, where the highest value is found in the daytime welding variation specimen with 53% air humidity, worth 89.42 J/mm2. From the ANOVA test results, the average tensile test and impact test have no significant differences.

Use of the geospatial technologies and its implications in the maritime transport and logistics

All the shipping industry and also ship building (shipyards) are under a complex process of digital transformation (DT), and so are the maritime ports as part of this logistic chain of significant importance. This paper aims to review the successive information technology (IT)-based generations that impacted the maritime transport and logistics (computer-based optimization of transport routes; use of intelligent sensors and IoT; position monitoring by using geospatial technologies and databases; intelligence-based decisions), to identify their main features, and to propose an autonomous vessel-port management system that can be implemented in the future. The role of the geographic information system (GIS) is emphasized – as GIS-based electronic route optimization that allows ships to follow new paths and deliver goods in the most economical and efficient way; GIS-based location precision with the use of on board and ashore GIS-based sensors (electro-optics, remote sensing, LiDAR). The shipping digitalisation process is heading towards a totally autonomous and at the same time safe and reliable ship. Complete autonomy could be reached by adjoining artificial-intelligence controlled systems designed to navigate and operate the ship and that are equipped with sensing and analysis tools, situational awareness, planning, and control capabilities. The Vessel Traffic System (VTS) of the future needs innovative technologies and methodologies to be developed. The desired systems will automatically collect and process data with high precision, will provide input to decision-making systems, and suggest evasive maneuver; to deal with hazards and systems failure without human intervention onboard. The use of new technologies comes with new types of risks specific to maritime transportation and seaports (spoofing, data manipulation, cyber-attacks etc.) The implications of the findings are important for all stakeholders involved in maritime transport and associated logistics (seaports).

Обеспечение экологической безопасности акваторий Российского арктического шельфа и повышение безопасности морских экосистем за счет снижения шумового загрязнения

Object and purpose of research. Ensuring the environmental safety of the Russian shelf waters requires constant development of methods and technologies related to monitoring, quantitative assessment and reduction of the harmful effects of pollution sources. During the industrial and transport development of the water area of the Northern Sea Route (NSR), an intensive increase of underwater noise is observed. Obtaining an adequate picture of the impact of underwater noise sources on representatives of the marine ecosystem creates a need to involve more and more modern and accurate measurement techniques. The article describes the draft methods for measuring the self-noise of carrier vessel and underwater noise of a selected marine equipment object, which were developed in order to identify the degree of impact of noise pollution over to the ecological situation in the considered water area. Materials and methods. An hydro acoustic signals contains the self-noise of measuring vessel, the noise of an object of marine industrial equipment (OMIE) and the noise of the water area where acoustic tests are going on. This acoustic signals are perceived by combined sound pressure and sound pressure gradient transducers, as well as by an omnidirectional hydrophone, located in the receiving system , and are converted into electrical signals transmitted via the main cable to the onboard post of the measuring vessel. Signals are sent to the hydro acoustic guidance beacon via the same cable to control the operation of this beacon. The information processing procedure is set out in the SIGAK VP Operation Manual (MGFK.411711.327 RE). The main purpose of the primary processing is to obtain 1/3-octave spectra and levels of underwater noise generated by the tested carrier vessel or OMIE, as well as the noise of the water area where these tests are carried out. In accordance with the accepted classification, the method of measuring sound pressure levels using a hydro acoustic complex according to this technique refers to indirect methods with single observations. Main results. In the course of the work, preliminary methods for measuring the self-noise of measuring vessel and underwater noise of a selected marine industrial object were developed. To measure the levels of underwater noise in 1/3-octave frequency bands in the range from 5 Hz to 10,000 Hz, within the framework of the draft methods, it is planned to use a stationary measuring hydro acoustic complex with a vector receiver from the GIK-VP. The signal processing algorithms are based on the spatial-frequency filtering of the acoustic power flux density components, which makes it possible to protect the measurement information from interference signals whose propagation direction does not coincide with the direction to the measured object. Conclusion. The results obtained in the form of implemented preliminary methods are important for the creation of regulatory documentation for the regulation of technogenic underwater noise in the waters of the Russian jurisdiction, reducing the intensity of noise pollution and the detrimental impact over to marine ecosystems. The article targeting the support at the stages of acoustical marine technical design, construction and operation of offshore industrial facilities and ships of various types, acoustic monitoring of the compliance of marine equipment with international standards for underwater noise.

The shipyard technological level evaluation methodology

A competitive advantage over other shipyards is extremely important in the high-stake shipbuilding industry. Typically, a competitiveness analysis of a shipyard measures productivity based on specific parameters, such as tonnes or compensated gross tons produced per consumed working hour. The authors of this paper consider identifying the technological level required to achieve this productivity as essential, including other information relevant for the shipbuilding process. Therefore, a methodology for determining the technological level of shipyards is proposed based on defined criteria and a structured evaluation. The criteria were devised and structured hierarchically. The methodology also offers company management a solution for continuous monitoring for improving shipyard design and production processes.