• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.86-91
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• 2012

Door effort was calculated for a new door checker with torsion bar spring and integrated checker case by FE analysis. A hybrid checker arm which has peaks and valleys only on the upper surface was adopted to reduce noise in operation and make operation with more distinctive steps. The checker arm was modeled using shell elements to estimate both the longitudinal and the lateral resistance force by checker arm. By combining the checker arm resistance force obtained from analysis and the door self-closing force by the theoretical calculation, door effort was predicted to show the good correlation with test results. In addition the unrolling effect of roller model was investigated and a new roller type for more smooth rolling was studied.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.406-409
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• 2005

In the forging operation of large ingot two break-down process are upsetting and cogging. The first purpose of upsetting is to ensure sufficient forging ratio for subsequent cogging operations and consolidate the voids along the centerline. The second purpose is related to improve the physical properties for a final product. Voids which are generated during the casting process can be one of the decisive defects of materials. So it is necessary to know the standard of Judgment for void-closure in upsetting operation. In practical conditions, FEM analysis(DEFORM 2D 8.1) was carried out to decide how much effective strain has influence on void-closure. It is finally suggested that the function consists of the effective strain of analysis data and the area rate of void.

• IE interfaces
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• v.14 no.1
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• pp.1-8
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• 2001

This paper presented a web-based virtual system to simulate forging operation. The system utilized simulation techniques of Finite Element Method (FEM) to analyze the forging process and Virtual Reality Modeling Language (VRML) to visualize the simulation results in the web. The analysis using FEM could show mechanical information such as stresses and deformation profiles of a specimen during forging process and the analysis results were transferred into virtual space using VRML. Since the forging machine and specimen were modeled using Java and VRML, the forging machine and analysis results were browsed and integrated on the web that is interfaced to users through EAI to show the whole forging simulation. The developed system realized the working environment virtually so that education and experiment could be performed effectively even on the PC.

• Journal of Fashion Business
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• v.10 no.3
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• pp.87-99
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• 2006

For comprehending the duties of fashion designer, Sharon(1989) has suggested to look at the procedure how the goods are being produced. The purpose of this research is to identify the task of domestic fashion designer by comparing and analyzing one's work range and performing level in the fashion merchandising process according to the brand types which one is involved in. The preliminary research for the questionnaire was conducted with 5 chief designers of woman's apparel manufactures in Seoul. They were asked to judge if designer's tasks fit to their carry-out operations in the pre-fixed questionnaire which had been done based on preliminary researches and literatures related with fashion merchandising process. The contents of research questionnaire are 11 questions to understand the general characteristics of companies and the participated subjects, and 42 questions to understand the designers' operations. For the selection of NB, among 503 domestic female apparel brands that were in 'Korean Textile Fashion yearbook (2002-2003), the companies that were located in Seoul and possible for cooperation by researcher's personal relationship were selected. For DB, cooperation was requested for brands that were located in Seoul among the 137 brands that participates on Domestic Collection. For GB, 50 stores were selected at random or by personal relationship among 32 GB shops such as Freya Town, Doosan Tower, New Zone, and so on. Total 300 questionnaire distributed to the designers, 192 copies were used for final data analysis. For data analysis, descriptive statistics and ANOVA, Sceffe test were used using SPSS V. 11 1. The participated fashion designers operated 41 categories of suggested 42 categories in the fashion merchandising process. 2. The ranges and contents of tasks in the fashion merchandising process that fashion designers mainly carry-out are very different according to the brand types and showed much different level of task carry-out. Only in the categories of 'fashion trend information' and 'design ideation', all three brand type showed the highest level of task performance. And the design related tasks presented common higher level of performance than the other tasks in all brand types. In order to comprehend the operation of fashion designer, various approaching methods are required according to various apparel manufactures' characteristics.

• Journal of Ocean Engineering and Technology
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• v.34 no.5
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• pp.342-350
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• 2020

In this study, a hydrate inhibition system is investigated for shallow water gas fields. Mono-ethylene glycol (MEG) injection has been used as a typical method for inhibiting hydrate formation in gas fields; therefore, most offshore platforms are equipped with MEG injection and regeneration processes. A recent application of a kinetic hydrate inhibitor (KHI) has reduced the total volume of MEG injection and hence reduce the operating cost. Experiments are designed and performed to evaluate and verify the KHI performance for inhibiting hydrate formation under shallow water conditions. However, the shut-in and restart operation may require the injection and regeneration of MEG. For this operation, the MEG concentration must be optimized while considering the cost of MEG regeneration. The obtained results suggest that decreasing MEG concentration from 80 wt% to 70 wt% can reduce the life cycle cost (LCC) of MEG regeneration process by approximately 5.98 million USD owing to reduced distillation column cost. These results suggest that the hydrate inhibition system must be evaluated through well-designed experiments and process simulations involving LCC analysis.

• Journal of the Korea Institute of Military Science and Technology
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• v.25 no.2
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• pp.177-186
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• 2022

A network QoS model for the joint integrated C4I structure was proposed for the integration of network infrastructure and network operations(NetOps) for NCOE. Detailed QoS requirements process of the joint integrated C4I systems are needs in the Multi-Domain Operation Environment(MDOE). A process is proposed for identifying QoS requirements and establishing in the MDOE using JMT(Joint Mission Thread) reference architecture and solution architecture. Mission analysis identify JCOAs(Joint Critical Operational Activities) and related activities based on JMT & System architecture's OVs, and Information analysis identify QoS attributes using System architecture's SVs. Identifying QoS attributes will be registered at PPS Registry by pre-regulated process, and will be set-up by NetOps. MDOE QoS requirement Process will support efficiently MUM-T and smart defense platform users under the future uncertain battlefield circumstances.

• Journal of the Korea Society of Computer and Information
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• v.28 no.10
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• pp.267-275
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• 2023

The digital transformation of the shipbuilding, shipping, and logistics sectors is predicted to lead to the introduction of autonomous ships and changes in the way ships are operated. The co-existence of various operation forms, such as autonomous operation and remote operation, with the existing operation methods is expected to lead to the transformation of the ship operation process and the emergence of new stakeholders. This paper studies the future ship operation process according to the change in ship operation method, predicts the change in the operating environment of future ships, and derives functional requirements by major tasks and stakeholders. The Delphi technique is applied to construct a ship operation scenario from the planning stage of voyage and cargo transport to the stage of arrival at the final destination port and discharge of cargo, and to predict future work changes by task and actor. Seafarers' activities are expected to be minimised by remote and autonomous operation, and experts in each field are expected to have responsibilities and tasks in different aspects of ship operation.

• Proceedings of the Safety Management and Science Conference
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• 2009.11a
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• pp.187-201
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• 2009

Semiconductor industry is based on equipment industry and timing industry. In particular, semiconductor process is very complex and as semiconductor-chip width tails and is becoming equipment gradually more as a high technology. Equipment operation is primarily engaged in semiconductor manufacturing (engineers and operator) of being conducted by, equipment errors have also been raised. Equipment operational data related to the error of korea occupational safety and health agency were based on data and production engineers involved in the operator's questionnaire was drawn through the error factor. Equipment operating in the error factor of 9 big item and 36 detail item detailed argument based on the errors down, and 9 big item the equipment during operation of the correlation error factor was conducted. Each of the significance level was correlated with the tabulation and analysis. Using the maximum correlation coefficient, the correlation between the error factors to derive the relationship between factors were analyzed. Facility operating with the analysis of error factors (big and detail item) derive a relationship between the model saw. The end of the operation of the facility in operation on the part of the two factors appeared as prevention. Safety aspects and ergonomics aspects of the approach should be guided to the conclusion.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.1
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• pp.116-121
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• 2019

The LVDT (Linear Variable Displacement Transducer) type sensor used for the existing ship's steering gear is simple on / off that does not perform proportional control operation to the control & unloading device. When the main spool is located at both extremes, It is reflected in the price by using an expensive sensor for import. In this paper, the Hall Effect Sensor is applied to Hydraulic Locking Alarm to analyze classification rules, structure, characteristics and operation principle of valves, and research on localization development in terms of cost reduction. The comparative analysis of the existing prototypes and the cause analysis of the problems were carried out, and the structural analysis showed satisfactory results within the allowable stress range. In addition, it was verified through experiments that the actual operation is realized by applying the actual developed product, and it was confirmed that the load on the maximum value exceeds the allowable maximum load even in the case of the universal tensile test in preparation for the departure of the rod casing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1816-1819
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• 2003

As a result of milling operation, we expect to have burr at the outward edge of workpiece. Also, it causes undesirable problems such as deburring cost, low quality of machined surface, and bottleneck in manufacturing process. Though it is impossible to totally remove burr in machining, it is necessary to plan a machining process that minimizes the occurrence of burr. In this paper, a scheme is proposed which identifies the tool path of the milling operation with minimum burr. In the previous research, a Burr Expert System was developed where the feature identification, the cutting condition identification, and the analysis on exit burr formation are the key steps in the program. The Burr Expert System predicts which portion of workpiece would have the exit burr in advance so that we can calculate the burr length of each milling operation. Here, the critical angle determines whether the burr analyzed is an exit burr or not. So the burr minimization scheme becomes to minimize the burr with critical angle. By iterating all the possible tool paths in certain milling operation, we can identify the tool path with minimum burr.