• Korean Journal of Computational Design and Engineering
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• v.17 no.2
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• pp.111-122
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• 2012

Capacity planning plays an important role not only for master production plan but also for facility or layout design in shipbuilding. Product work breakdown structure, attributes of production resources, and production method or process data are associated in order to make the discrete event simulation model of shipyard layout plan. The production amount of each process and the process time is assumed to be stochastic. Based on the stochastic discrete event simulation model, the production capacity of each facility in shipyard is estimated. The stochastic model of product arrival time, process time and transferring time is introduced for each process. Also, the production capacity is estimated for the assumed master production schedule.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.4
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• pp.450-457
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• 2018

The determination of assembly sequence in general mechanical assemblies plays an important role in terms of manufacturing cost, duration and quality. In the production of ships and offshore plants, the consideration of productivity factors and welding deformation is crucial in determining the optimal assembly sequence. In shipbuilding and offshore industries, most assembly sequence planning has been done according to engineers' decisions based on extensive experience. This may result in error-prone planning and sub-optimal sequence, especially when dealing with unfamiliar block assemblies composed of dozens of parts. This paper presents an assembly sequence planning method for block assemblies. The proposed method basically considers geometric characteristics of blocks to determine feasible assembly sequences, as well as assembly process and productivity factors. Then the assembly sequence with minimal welding deformation is selected based on simplified welding distortion analysis. The method is validated using an asymmetric assembly model and the results indicate that it is capable of generating an optimal assembly sequence.

• Journal of Korean Institute of Industrial Engineers
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• v.37 no.3
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• pp.198-208
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• 2011

At a shipyard, the efficient handling of blocks is one of the most important factors in the shipbuilding process. We consider the problem of deployment planning of blocks from storage yards. As some information of block arrangement should be considered to handle the problem, we adopt the block arrangement based on the coordinates and sizes of each block at a storage yard. Deployment planning for a block involves deciding upon its transportation route from the storage yard and searching for blocks that would obstruct its transportation along this route. A tabu search algorithm for deploying several blocks is developed to minimize the number of obstructive blocks deployed together from the storage yards at a shipyard. The results of computational experiments show that the developed algorithm is very useful in the deployment planning of multiple blocks from the storage yards.

• Journal of the Society of Naval Architects of Korea
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• v.31 no.1
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• pp.42-49
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• 1994

The purpose of CIM for shipbuilding should be focused on the efficient processing of information among design, process planning and scheduling activities. The most essential technology for shipbuilding CIM is the product model. This model should not only define a physical product "ship" but also a process "ship production". Major activity for ship production is assembly, which requires intensive use of the relationships among parts of ship structure. Other production information are painting area. shape. weight, etc. The fact that major ship structure is "stiffened-plate" type, which allows us to handle the plate thickness as non-geometric information for practical purpose. Therefore. the geometric model for ship product model should handle the relationship among parts(so called topology) efficiently. We find that a face oriented non manifold data structure can meet this requirement. We apply this non-manifold data structure to the ship compartmentation, structural design, and assembly.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.1-12
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• 1993

The role of product model in CIM environemt(where such heterogenous application programs as CAD, CAE, CAM, Database, and Expert Systems are included) is system integration. Product model manages all the information related to manufacuring activities. This information includes shapes, operation, process, scheduling, quality, and mangement. Product model architecture includes product model kernel, object schema, model manipulation language, and user interface. Objects to be shared are defined using the model manipulation luage and the defintions are saved in the object schema. In this paper, we present the design and implementation of a prototype. In this prototype, application programs for CAPP(Computer Aided Process Planning) are used.

• Journal of Korean Society for Quality Management
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• v.41 no.1
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• pp.149-162
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• 2013

Purpose: The purpose of this study was to design of a probabilistic model for optimum manpower planning in R&D department by Montecarlo simulation. Methods: We investigate the process and the requirement of manpower planning and scheduling in R&D department. The empirical distributions of necessary time and manpower for R&D projects are developed. From the empirical distributions, we can estimate a probability distribution of optimum manpower in R&D department. A simulation method of estimating the probability distribution of optimum manpower is considered. It is a useful tool for obtaining the sum, the variance and other statistics of the distributions. Results: The real industry cases are given and the properties of the model are investigated by Montecarlo Simulation. we apply the model to the research laboratory of the global company, and investigate and compensate the weak points of the model. Conclusion: The proposed model provides various and correct information such as average, variance, percentile, minimum, maximum and so on. A decision maker of a company can easily develop the future plan and the task of researchers may be allocated properly. we expect that the productivity can be improved by this study. The results of this study can be also applied to other areas including shipbuilding, construction, and consulting areas.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.421-431
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• 2017

A process-centric simulation modeling method has been proposed to define a shipbuilding simulation model. Existing modeling methods have limitations for expressing various production information for a shipyard. The advanced process-centric modeling method proposed in this paper offers an improvement, effectively representing production information and constraints for a shipyard. To achieve this, a method and diagram components to define a process-centric simulation model in detail have been suggested. The modeling method can assign priorities when multiple products and facilities are assigned to the process. And layer concept was applied to express simulation model with hierarchical structure. To verify the effectiveness of the modeling method, comparative analysis has been performed and the actual shipbuilding process has been modeled using the proposed method. When a single facility was used for various purposes, we found that the proposed method was more advantageous than existing methods. As a result, it was possible to express constraints and flows that were difficult to identify with existing process-centric simulation modeling methods, and the methods were improved for use in shipyard production planning verification simulations.

• Journal of Fashion Business
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• v.14 no.2
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• pp.110-126
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• 2010

The purpose of this study is for finding the demand and perception about color situation of the working environment including work places and working clothes according to the workers in the machinery automobile shipbuilding companies. Data were collected by questionnaire surveying 679 workers. The collected data were analysed through frequency, mean, cross tabs analysis by SPSS for windows 17.0. As a result, most of the workers responded that they were not satisfied with the current working environment and the colors of their working clothes. However, the workers held a perception that influence that the colors of the working environment has on their psychology and safety or the colors' role was relatively significant. And they had a very positive expectation for the effect of the working clothing's color planning. The study would serve as the beneficial information for formulating the safer and more pleasant working environment in industrial work places as well as a basic material for the subsequent research on colors.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.1
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• pp.29-36
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• 2016

In shipbuilding and offshore plant construction, pipe-stools of various types are installed. Moreover, these are many quantities but they must be installed in a successive manner. Due to these characteristics the pipe-stool installation processes easily tends to cause the schedule delays in the overall production processes. In order to reduce delay, the goal of this study is to predicts production’s lead time before manufacturing. Through this predictions it’s expected to reduce total production’s lead time by improving it's process. First of all, we made MLR(Multiple Linear Regression) and PLSR(Partial Least Square Regression) model to predict pipe-spool's lead time and then compared predictability of MLR and PLSR model. If a explanatory variable is added, it will be possible to predict results precisely.

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