• Journal of Ocean Engineering and Technology
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• v.30 no.6
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• pp.526-534
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• 2016

This study had the goal of designing onboard structures for a pre-pilot mining test (PPMT), which is required for the commercialization of the deep-sea mining industry. This PPMT is planned to validate the performance of a hydraulic lifting system and verify the concept of operating through a moon-pool in the east sea, Korea. All of the onboard equipment and facility were designed by KRISO. Because the test was performed at the first development, it is difficult to determine what risk will occur in the facility. Therefore, risk-based design is required in the facility for the PPMT, which includes the facility layout, failure mode and effect analysis (FMEA), and risk reduction plan. All of the expected performances of the lifting system itself and the onboard facilities were qualitatively validated using the risk-based design.

• Nuclear Engineering and Technology
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• v.42 no.6
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• pp.690-703
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• 2010

Sampling based uncertainty analysis was carried out to quantify uncertainty in predictions of best estimate code RELAP5/MOD3.2 for a thermal hydraulic test (10% hot leg break LOCA) performed in the Large Scale Test Facility (LSTF) as a part of an IAEA coordinated research project. The nodalisation of the test facility was qualified for both steady state and transient level by systematically applying the procedures led by uncertainty methodology based on accuracy extrapolation (UMAE); uncertainty analysis was carried out using the Latin hypercube sampling (LHS) method to evaluate uncertainty for ten input parameters. Sixteen output parameters were selected for uncertainty evaluation and uncertainty band between $5^{th}$ and $95^{th}$ percentile of the output parameters were evaluated. It was observed that the uncertainty band for the primary pressure during two phase blowdown is larger than that of the remaining period. Similarly, a larger uncertainty band is observed relating to accumulator injection flow during reflood phase. Importance analysis was also carried out and standard rank regression coefficients were computed to quantify the effect of each individual input parameter on output parameters. It was observed that the break discharge coefficient is the most important uncertain parameter relating to the prediction of all the primary side parameters and that the steam generator (SG) relief pressure setting is the most important parameter in predicting the SG secondary pressure.

• Journal of Wellbeing Management and Applied Psychology
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• v.7 no.1
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• pp.27-33
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• 2024

Purpose: This study investigates human error accidents in the Korean railway sector, emphasizing the need for systematic management to prevent such incidents, which can have fatal consequences, especially in driving-related jobs. Research design, data and methodology: This paper analyzed data from the Aviation and Railway Accident Investigation Board and the Korea Transportation Safety Authority, examining 240 human error accidents that occurred over the last five years (2018-2022). The analysis focused on accidents in the driving, facility, electric, and control fields. Results: The findings indicate that the majority of human error accidents stem from negligence in confirmation checks, issues with work methods, and oversight in facility maintenance. In the driving field, errors such as signal check neglect and braking failures are prevalent, while in the facility and electric fields, the main issues are maintenance delays and neglect of safety measures. Conclusions: The paper concludes that human error accidents are complex and multifaceted, often resulting from a high workload on engineers and systemic issues within the railway system. Future research should delve into the causal relationships of these accidents and develop targeted prevention strategies through improved work processes, education, and training.

• The Transactions of the Korea Information Processing Society
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• v.6 no.5
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• pp.1385-1392
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• 1999

This paper describes the design of the monitoring system for monitoring the current status and indirect controlling of the Wet Station Equipment which is used for cleaning the wafer. Most of the conventional monitoring system depend on the special hardware and software. Basic design goal of monitoring system is provide the convenience for the use and the portability for the system. In order for the system to fulfil its requirements, it was designed using GUI (Graphical User Interface) facility based on the windows NT environment of IBM PC compatible and EtherNet board based on the TCP/IP protocol.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.132-137
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• 2018

Although the number of chemical accidents has been declining since the Chemical Control Act of 2015, there have been repeated occurrences of similar types of accidents at printed circuit board (PCB) manufacturing facilities. These accidents were caused by the overflow of hydrochloric acid and hydrogen peroxide, which are toxic chemicals used in the printed circuit board manufacturing process. An analysis of the $Cl^-$ content to identify the cause of the accident showed that in the mixed route of hydrochloric acid and hydrogen peroxide, which are accidental substances, the $Cl^-$ concentration was 66.85 ppm in the hydrogen peroxide sample. Through reaction experiments, it was confirmed that the deformation of a PVC storage tank and generation of chlorine gas, which is a toxic gas, occurred due to reaction heat occurring up to $50.5^{\circ}C$. This paper proposes a facility safety management plan, including overcharge, overflow prevention, leak detection device, and separation tank design for mixing prevention in printed circuit board manufacturing facility etch process. To prevent the recurrence of accidents of the same type, the necessity of a periodic facility safety inspection and strengthening of the safety education of workers was discussed.

• Design & Manufacturing
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• v.14 no.3
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• pp.17-22
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• 2020

As devices such as smartphones, tablet PC, and wearable devices have been miniaturized, the connectors that go into the devices are also designed to be very small. The connector combines the plug and the receptacle to transfer electricity. As devices are miniaturized, the contact shape is formed by partially thinning the thickness of the raw material of the terminal in order to lower the coupling height of the plug and receptacle. The product used in this study is a receptacle terminal used for 0.4mm pitch board to board connector among fine pitch connectors. When the material thickness is reduced by forging the receptacle terminal, the width change of the pin is checked. To reduce the thickness of the material by forging, pre-notching is applied in the first step, forging in the second step, and notching in the third step. After forming the width dimension of the pin to 0.28 mm in the pre-notching process, in the forging process, the material thickness 0.08 mm and 0.02 mm (25%) were forged and the thickness was changed to 0.06 mm and the width change amount of the pin was measured. The facility produced 10,000 pieces at 400 SPM using a Yamada Dobby (MXM-40L) press, and thirty pins were measured and the average value was shown. After forging by using C5210-H (HP) and NKT322-EH, which are frequently used in connectors, analyze the amount of change in each material. The effect of punching oil on forging is investigated by appling FM-200M, which is highly viscous, and FL-212, fast drying oil. This study aims to minimize mold modification by predicting the amount of material change after forging.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.3
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• pp.454-459
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• 2018

The BIPV system must be designed to reflect the architectural and electrical characteristics simultaneously because it replaces the role of the exterior material of the building, which makes it difficult to design the BIPV. The thin film type BIPV module has an electrical characteristic that the open voltage is higher and the short circuit current is lower than that of the crystalline type BIPV module. However, there are many differences in the design of the array, the collector distribution board, and the inverter in the system configuration since the crystal type BIPV module has the opposite feature. In this study, a crystalline BIPV module and a thinfilm BIPV module were applied to actual buildings. As a result, the elements to be considered in designing BIPV system were derived, and the architectural and electrical characteristics were mutually analyzed.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.109-118
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• 2012

The study is aimed to suggest a preliminary data on the improvement of children's recreational facility to enhance children's creativity at Sangsang Children Park Project(SCPP) in Seoul Metropolitan City being the case study. The book review, especially the field observation was implemented by the video recording methods for analyzing the children's play behavior with regard to the six sites of the SCPP that was constructed in March 2008 until May 2010. Because of the research, the first 21 patterns of the creative activities were shown. Second, the prime using rates of facilities were the combination of play facilities among other play facilities like swings, slides, trembling horse etc. However, more children's creative behaviors occurred on independent play facilities like swing, trembling horse, etc. than at combination play facilities. Third, children's creative behaviors diversely occurred at a moving or fluid facility like a swing, trembling horse and a spatial facility like sand field more than a fixed facility like combination play facility. Fourth, children's creative behavior could be divided and evaluated by five categories and elements of fluency: the flexibility, the creativity, the elaborateness, and the imagination. Nevertheless, it was assumed that the creative elements of the five categories were mixed together with each other instead of showing an individual characteristic. Fifth, based on this analysis, the research reached out to the conclusion that the combination play facility of imaginary children's park would be designed together with more fluid and spatial facilities to improve the children's creativity. Finally, It was proposed that the play facilities of imaginary children's park like drawing wall or board, spatial play facilities and handicraft facilities etc. would be introduced to improve sorts of creativeness on elaborateness and imagination shown less than the fluency, flexibility, and originality.

• Ocean Systems Engineering
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• v.9 no.4
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• pp.391-407
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• 2019

Tracking the location (position) of a surface or underwater marine vehicle is important as part of guidance and navigation. While the Global Positioning System (GPS) works well in an open sea environment but its use is limited whenever testing scaled-down models of such vehicles in the laboratory environment. This paper presents the design, development and implementation of a low energy ultrasonic augmented single beacon-based localization technique suitable for such requirements. The strategy consists of applying Extended Kalman Filter (EKF) to achieve location tracking from basic dynamic distance measurements of the moving model from a fixed beacon, while on-board motion sensor measures heading angle and velocity. Iterative application of the Extended Kalman Filter yields x and y co-ordinate positions of the moving model. Tests performed on a free-running ship model in a wave basin facility of dimension 30 m by 30 m by 3 m water depth validate the proposed model. The test results show quick convergence with an error of few centimeters in the estimated position of the ship model. The proposed technique has application in the real field scenario by replacing the ultrasonic sensor with industrial grade long range acoustic modem. As compared with the existing systems such as LBL, SBL, USBL and others localization techniques, the proposed technique can save deployment cost and also cut the cost on number of acoustic modems involved.

• Journal of Industrial Convergence
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• v.20 no.11
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• pp.197-203
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• 2022

The purpose of this study is to establish an S.I. (Space Identity) considering the spatial location and cultural specificity of Jecheon Jungang Market, the oldest and largest market in Jecheon with historical characteristics. To this end, we identify the flow of the cultural tourism market, investigate and analyze the current state of Jecheon Central Market, and present a direction based on storytelling for each space. The concept of space design was divided into space, time, people, and culture as coexistence, and merchants, products, and shopping malls share temporality and coexist in one space. Therefore, the facilities for each floor consisted of a gate, information board, lighting, rest area, design bench facility, information center, business compliance line, floor sign, and gate floor sign for each floor. Through this, it is necessary to establish a mid- to long-term development strategy by establishing a step-by-step promotion strategy to predict the economic effect of creating new demand and increasing sales in Jecheon Central Market.