• Corrosion Science and Technology
• /
• v.7 no.5
• /
• pp.274-282
• /
• 2008

Ships' hull is typically protected by a combination of protective coating system and electrical cathodic protection system, which has been an economical and effective measure for ship's hull to date. However, ships' rudder and adjacent hull areas are known to be subjected to premature corrosion damages, which require more frequent coating repair than other hull areas. Conventional organic coating system for ship's hull has been known only to remain intact just for 2~3 months on the rudder and adjacent area, especially for the fast-going ships such as container carriers or naval vessels. In this study, special organic/inorganic coating materials, which are commercially available, were tested in terms of cavitation resistance as an alternative to existing rudder & hull protection system. Both standard ultrasonic tester and in-house developed ultra water jet test method were employed as a means to evaluate their performance against cavitation induced damages. Additionally, the overall cost evaluation and workability at actual shipyard were discussed.

• Safety and Health at Work
• /
• v.3 no.2
• /
• pp.104-109
• /
• 2012

Singapore, an island republic of over 5 million inhabitants, has 3.1 million workers. Most are employed in the service, finance and tourist/transport industry. Significant numbers work in manufacturing, construction and heavy industry. Following a series of construction and shipyard accidents with multiple deaths in 2004, the government announced its intention to reduce workplace fatalities from 4.9 to 2.5 per 100,000 by 2015. There was strong political will to achieve this target. The strategic approaches were to build workplace safety and health (WSH) capabilities; implement legislative changes with enforcement; promote benefits of WSH and recognize best practices, and enhance partnership with stakeholders. The anticipated outcomes were to reduce workplace fatality and injury rates; have WSH as an integral part of business; and establish a progressive and pervasive WSH culture. With these measures, the workplace fatality rate declined from 4.9/100,000 in 2004, to 2.2/100,000 in 2010. However, other confounding factors could also account for this decline, and have to be considered. The next target, announced by Singapore's Prime Minister in 2008, is to further reduce the workplace fatality rate to 1.8/100,000 by 2018, and to have "one of the best workplace safety records in the world".

• Special Issue of the Society of Naval Architects of Korea
• /
• 2011.09a
• /
• pp.55-62
• /
• 2011

Although the performance of the commercial vessel has been dramatically improved through innovations, there has been no big changes on the traditional anchoring method of commercial vessels, both on design and operation until now. In this paper, two cases of design modifications were introduced for optimized design of pocket type anchor handling, which resulted in improved performance of the vessel's anchoring. From the first time fully balanced type anchors were applied on vessels in Korean shipyard, main design problem on this application was that the anchor doesn't normally slide into the pocket when the anchor fluke is not in line with pocket, as the anchor freely rotates by the swivel on forerunner. In order to prevent the problem, swivel has been deleted on the forerunner to prevent anchor rotation until now, but this solution caused problems such as twist lock of anchor chain, restriction of windlass direction, etc. On this paper, one of the solution is introduced to overcome the design problem by tilting the hawse pipe to some extent, which makes anchor turned at the time anchor ring touches the pocket skirt and that it properly slides into the pocket. Secondly, one of the solution is introduced to overcome misalignment problem between anchor chain cable and roller of chain compressor, which has been frequently occurred, by modification of roller design.

• Journal of the Society of Naval Architects of Korea
• /
• v.46 no.3
• /
• pp.362-371
• /
• 2009

Shipbuilding is a typical 'build to order' industry. It has a business model that generates revenues from building various ships and offshore products in accordance with owner's requirements at each production stage. Under uncertainty in shipping market, it is very essential for the shipbuilder to prepare the fast and competitive decision for product portfolio strategy in order to maximize contribution margin by exploiting production facilities and constraints. In this study, we introduce the unique decision supporting methodology for the optimal product portfolio sets based on Theory of Constraints(TOC). This methodology is established by adopting the concept of Drum Buffer Rope(DBR) in constraints planning and Throughput Accounting (TA) in management accounting of TOC. In addition, Decision Supporting System(DSS) is implemented. This DSS system provides a throughput estimator with reflecting the cost structure of shipbuilding industry and a resource simulator built on heuristic algorithms to operate major constraint-resources in shipyard such as dock, quay and pre-erection area etc. Several examples are presented to show that the proposed methodology and system can effectively support the strategic decision-making process of a global shipbuilding company.

• Journal of the Society of Naval Architects of Korea
• /
• v.30 no.2
• /
• pp.123-131
• /
• 1993

Since the years of oil tanker production in the 70's, the concern of marine enviromental protection is worldwidely increased, at last it is compulsorily ruled to product the double hull tanker by International Maritime Organization(IMO). Throughout these informative years Daewoo Shipyard has developed the double hull VLCC for a future vessel. The paper presents hull design for 300K double hull VLCC which was carried out to satisfy with statutory requirement of it, focused the structural arrangement and direct calculation in cargo hold area.

• Journal of the Society of Naval Architects of Korea
• /
• v.43 no.2 s.146
• /
• pp.228-235
• /
• 2006

Nowadays, digital manufacturing has been known to be very effective method in manufacturing fields. It is aimed to estimate process time, to improve operation efficiency, and to prevent bottleneck processes in advance of real manufacturing. This paper addresses a scheduling support system for panel hues in a shipyard through digital manufacturing simulation. The proposed system supports operators to make better decisions on the shop-floor scheduling in panel lines. It ,would provide a complete schedule that is at least as good as any schedule currently obtained. Furthermore, it can evaluate the operator's schedule by simulating it with 3-dimensional models before the work orders and schedules are released.

• Journal of the Society of Naval Architects of Korea
• /
• v.42 no.6 s.144
• /
• pp.679-685
• /
• 2005

Until now, the stealth design to reduce the infrared signature of ship haven't been carried out using the proper design criteria. The study on the maritime meteorological environment in the Korean seas hasn't been accomplished yet, so the design criteria of the maritime meteorological environment was just given by the engineering sense without experience of the Navy and/or of the shipyard. Even in rather good conditions(summer condition), the estimated IR signature of a ship showed larger values and couldn't predict the worst condition during the operation of a ship at sea. In this study, domestic maritime meteorological data were collected and variables affecting the IR signature of a ship had been derived through the sensitivity study of IR signature according to the maritime meteorological environment in Korean seas. The basic study on the criteria of the stealth design of IR signature has been carried out.

• Journal of the Ergonomics Society of Korea
• /
• v.35 no.6
• /
• pp.611-619
• /
• 2016

Objective:This study aims to analyze the relationships between personality factors measured by Minnesota Multiphasic Personality Inventory (MMPI) scales and the indices of safety and health in the shipbuilding industry. Background: Many researches reported that there were significant relationships between some MMPI subscales and traffic and industrial accidents. Method: This study analyzes 230 male workers in shipyard for their MMPI scores gathered during recruitment process and their safety and health indices from the performance record during their working period. ${\chi}^2-test$ and one-way ANOVA are used for finding the statistical significance for personality factors. The conventional grouping rule for MMPI scales and other grouping criteria considering the attitude of positive answer for the MMPI test during recruitment process are used for analysis. Results: The Hypomania (Ma) and Psychopathic Deviate (Pd) scales of the MMPI are the main factors related to the safety and health related indices for most grouping rules. Depression (D), Psychasthenia (Pt), Hypochondriasis (Hs), Schizophrenia (Sc), and Masculinity and Femininity (Mf) scales are also related to the safety and health indices. Conclusion and Application: The results can be used for understanding the psychological factors in human behaviors and safety and can help professional personnel take the necessary steps in improving safety on the job and also in providing the effective teaching of safe work methods.

• Journal of the Korea Society for Simulation
• /
• v.21 no.1
• /
• pp.1-8
• /
• 2012

In recent days, global shipbuilding companies have been showing great interest in eco-friendly ship products and trying to reduce environmental pollution - harmful gas and dust in shipbuilding process. Following this trend, Life Cycle Assessment (LCA) was carried out to an application of shipyards layout. LCA is a technique used to assess environmental impacts during the life cycle of products and systems. Until now, LCA has been used through ISO 14040 in somewhat limited industries, such as Building Life Cycle Assessment. Thus, this study analyzes the shipyard layout planning framework and builds life cycle inventory along with the simulation model structure to evaluate environmental impacts.

• Journal of the Korea Society of Computer and Information
• /
• v.12 no.4
• /
• pp.221-228
• /
• 2007

Qualify Function Deployment(QFD) is a technique which was born in Japan as a strategy for assuring that quality is built into new products. QFD was first used in 1972 by Kobe Shipyard of Mitsubish Heavy Industrials Ltd. and was then referred to as the quality tables. After QFD is proposed, it has been applied by both many large and small companies around the world. Many studies related QFD are performed till now but study related "cost-based QFD(QFCD)" hasn't been performed actively. If cost-based QFD is not performed. the produced results will be included possibility that is not significant as well as realistic. Therefore, the purpose of this study is to improve effectiveness and efficiency for product development's result through QFD by introducing QFCD's concept and execution procedure.