• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.2
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• pp.126-134
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• 2001

Statistical approaches for analysis of data from the limited number of samples in ship building industry(SBI) collected by an industrial hygienist for checking compliance to an occupational standard were considered. Sampling for compliance usually has been guided by judgment selection, rather than true randomness, resulting in the creation of compliance samples which approximate a censored sample from the upper tail of the exposure distribution. Similar exposure groups(SEGs) including welding and painting process were established to assess representative values in each groups after reviewing the whole production line in SBI. For the convenient statistical approaches, the code has assigned to each SEGs. The descriptive statistics and probability plotting were used to yield the representative values in each SEGs. In the first step, SEGs of 558 were established from 5 ship building companies. The 38 SEGs showed the uncertainty are divided into each 5 companies and assessed the representative values again. The 44 SEGs in each companies was not showed the normal and lognormal distribution was analyzed each data. And also, recommendation was suggested to resolve the uncertainty in each groups.

• Journal of Welding and Joining
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• v.26 no.4
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• pp.66-72
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• 2008

Because of high intensity and easy controllability of the heat source, high frequency induction heating has been concerned and studied for the steel forming process in the ship building industry. However, the heating and forming characteristics have to be further properly modelled and analyzed for the process to be utilized with its optimal working parameters. In this study, a modelling with thermo-elasto-plastic analysis is performed using the FEM to study heat flow and deformation of the steel plate during the forming process with the electro-magnetic induction heating. The numerical model is then used to study the effect of the inductor shape on the magnitude of angular deformation of the plate during the forming process. It is revealed that the square shape of inductor induces the largest deformation among the rectangular inductors.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.1 s.151
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• pp.48-54
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• 2007

Higher productivity and less cost during the manufacturing process of ships are required to maintain international competitiveness of modern shipbuilding industries. The integrated hull/ outfitting/ painting scheduling(IHOP) process is a final point, where logistics are finally being integrated and upcoming schedules are made. Therefore, more profits are expected from IHOP by effective management. In this thesis, IHOP is proposed in order to solve how to choose block erection date with IHOP scheduling logic. The result of IHOP scheduling is highly advised to utilize fabrication, outfitting shops. A standardized operation and load of resource will eventually be applied in long-term time span point of view for this will make it easy to enable capacity planning and workforce planning. It is also expected to eliminate inefficiency in overtime work and efficiently utilize manpower in short-term.

• Journal of the Institute of Convergence Signal Processing
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• v.21 no.1
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• pp.13-20
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• 2020

In shipyards, internal materials are assembled after designing and manufacturing each ship's block. Internal material assembly means the installation of parts and equipment except ship's body. In this process, if the assembly of pipes and equipment existing in the block is not done correctly during the assembly between blocks, this causes a lot of costs. In addition, even if the assembly of the internal materials already completed, the production efficiency of the ship is reduced due to rework when problems such as space arrangement of the internal materials occurs. Therefore, this study introduces space arrangement and inspection system before and after hull outfitting work based on coexistence reality technology using 3D design drawing to solve these problems. The various coexistence reality algorithms and inspection systems developed and introduced in this study are based on AR service, which has never been introduced in Korea. So it will be widely applicable to various manufacturing industries using design drawings such as automobiles and architectures as well as ship building process.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.03a
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• pp.39-51
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• 2002

Online exchange is a cost-effective approach to trade goods and information among multiple sellers and buyers. Shipping industry includes lots of global entities such as shippers, liners, ship owners and shipping agents. Marine insurance companies and ship repairers and many other groups are also supporting the industry. However, international shipping exchanges are located on few cities in the world. Its our motivation that a shipping market can be online so that market participants do the dealing while sitting where they are with more efficient manner, preferable price and larger pool of candidates of trading partners. This paper presents Korean governmental project of building a cyber shipping exchange. The exchange covers ship sale and purchase, charter, insurance, freight futures, repairs, supplying of ships oil and database service. The workflows of each business were analyzed and designed to fit for online environment. The project includes design of trading mechanism, online documents, data flow, data storage and security. Online match making and trading mechanisms such as auction, reverse auction, bid are used. The whole trading process involves multiple organizations and business processes. So, this Paper focuses on how each organization would play their roles so that users can complete transactions with integrated and transparent view. The online exchange selves also as maritime portal site that links to other sites for cooperation vertically or horizontally, and serves database and information in global perspective. This paper also issues and discusses the justification of an online shipping exchange

• Journal of Ocean Engineering and Technology
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• v.31 no.2
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• pp.141-154
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• 2017

A production management system is developed to enhance both the information and productivity of ship and offshore plant deckhouse floor outfitting. The functions of the production management system for the deckhouse floor outfitting were reviewed based on a literature survey of several production management systems with respect to the ship building and architecture fields. This study investigated numerous daily production reports and their application to actual work places to utilize the system development. The developed scanned drawing-based production management (SDPM) system minimizes any loss and/or distortion of work information between the workshop and management office when applying a scanned production drawing to the daily report. The SDPM system increases the data objectivity, as well as intuitiveness of the information generation by adopting an efficient user interface, which makes it possible to perform image annotations on the scanned drawing for the daily production report while simultaneously interacting with the production management database. Applying the system operation to actual deckhouse floor covering work verified that it was feasible to use the SDPM system for production management in the ship outfitting work process.

• Special Issue of the Society of Naval Architects of Korea
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• 2008.09a
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• pp.118-125
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• 2008

The deck plates of ship block is made of thin plates in their construction. A main reason of using thin plates is that deck plates don't need to support large structural loads. Therefore, out-of-plane deformations between stiffeners are frequent in deck blocks. Because these are got right by correction heating, they continuously causes quality problems in the final dock-building process. According to preceding research, the lifting process by cranes would offset the effect of correction heating. This study finds out the remained efficiency of correction heating when tensional loads are added by a lifting to corrected parts. We used inherent strains in calculating the efficiency, and established the methodology where the positions for callings are. For getting more accurate positions, besides the structural lifting analysis, welding deformation analysis with upper block and measured data from a serial ship are also referenced.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.9
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• pp.1-10
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• 2021

Recently, the repair and recycling of damaged mechanical parts via metal additive manufacturing processes have been industrial points of interest. This is because the repair and recycling of damaged mechanical parts can reduce energy and resource consumption. The directed energy deposition(DED) process has various advantages such as the possibility of selective deposition, large building space, and a small heat-affected zone. Hence, it is a suitable process for repairing damaged mechanical parts. The shaft is a core component of various mechanical systems. Although there is a high demand for the repair of the shaft, it is difficult to repair with traditional welding processes because of the thermal deformation problem. The objective of this study is to propose a repair procedure for a damaged shaft using the DED process and discuss its applications. Three types of cases, including a small shaft with a damaged surface, a medium-size shaft with a worn bearing joint, and a large shaft with serious damage, were repaired using the proposed procedure. The microstructure and hardness were examined to discuss the characteristics of the repaired component. The efficiency of the repair of the damaged shaft is also discussed.

• Structural Monitoring and Maintenance
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• v.10 no.1
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• pp.25-42
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• 2023

Despite the significance of ports as critical economic infrastructure, the berth facilities usually deteriorate due to heavy loading, unloading, aging, environmental weather conditions, marine growths, and lack of efficient maintenance management. Marine berths require proactive maintenance management to limit deterioration and defects as no berth facility is maintenance-free. Thus, delay in carrying out maintenance work for the marine berths can be devastating to the operational process involving ship entry, loading, and unloading operations. The aim of this research is to coordinate both operations work, and maintenance works that take place inside the berth of a local industrial port in Saudi Arabia, by developing a novel framework that integrates both works without affecting the efficiency and functionality of the berth. The study focused on defining the operational process of the port and identifying the elements with direct and indirect effects. In addition to determining the priority for the entry of ships inside the berth, it also identified the factors involved in designing a framework that included maintenance work as a component of the monthly berth occupancy schedule. By applying a mathematical model, a framework was established, which includes all the important elements of the process. As a result of the mathematical method formulation process, a database was designed that organizes and coordinates the operations of all berths within the port. This creates time to carry out the required maintenance work monthly as well as ease of coordination with the contractors responsible for the implementation of those works.

• Journal of Navigation and Port Research
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• v.36 no.6
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• pp.449-458
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• 2012

Recently many different floating buildings are planed and constructed in the sea, river, etc. for active use of water spaces. But many problems are occurred in the process of floating building design, construction and management due to the inadequate legal system. This incomplete legal system has become one of the critical factors which are hampering the invigoration of floating buildings. Therefore this study is to suggest preliminary data and improvement directions through a case study with domestic and foreign examples of appropriate laws and law applications concerning floating buildings. As the results of this study the laws related to floating building have to be revised in the directions of qualifying legally floating building as 'building' but not 'ship', designating 'special zone' for floating building site, and applying the established 'building licensing procedure' to floating building also.