• 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 Korean GEO-environmental Society
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• v.15 no.3
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• pp.21-32
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• 2014

This Research have suggested the new estimation method using parameter estimation algorithm to substitute established velocity and friction factor calculation equation. Established calculation equation has some difficulties for estimation and reflecting exactly flow specification cause parameter uncertainty and material uncertainty governed real phenomenon, so this research has used system modeling method for flow specification estimation and suggested estimation method.

• Korean Journal of Computational Design and Engineering
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• v.15 no.1
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• pp.60-69
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• 2010

Outfitting systems in marine vessels have many kinds of standard parts. Ship CAD system should support the designers with an efficient tool for the modeling of outfitting parts such as pipes and valves. We develop a practical procedure for a part master model that combines ship CAD systems with the industrial standard. Part master or catalogue database of standard equipments is included in the database of ship CAD. The part master makes the associations of three dimensional modeling with the industrial standard. Moreover, it reflects the automatic modeling to maintain attributes that are disclosed in the entity of each part master in order to reduce the modeling time. Entity and attributes of pipe and valves are chosen from JIS(Japanese Industrial Standards) in order to explain the proposed procedure. Suggested procedure explains that three dimensional model of equipment is generated by parsing the pre-defined attributes after the entities of part masters is stored in database.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.3
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• pp.77-86
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• 2010

In this study, the model of the indirect wind suction waste sorting machine for characteristics of the screening of waste was studied using computational fluid dynamics and the drag coefficient for the model and the suction wind speed were obtained. The wind separator are developing by installing a cyclone air outlet to the suction blower impeller waste is selective in a way that does not pass the features and characteristics of the inlet pipe of the pressure loss and separation efficiency can have a significant impact on. Using Wind separator for selection of waste in the waste prior research on the aerodynamic properties are essential. For plastic cases, it is reasonable to take the drag coefficient between 0.8 and 1.0, and for cans, compression depending on whether the cans, the drag coefficient is in the range from 0.2 to 0.7. The separation efficiency of waste as change suction speed was the highest efficiency when the suction speed was 25~26 m/s. Shape of the inlet, depending on how the transfer pipe of the duct pressure loss occurs because the inlet velocity changes through the appropriate design standards to allow for continued research is needed.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.130.1-130.1
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• 2010

미국과 유럽에서는 이미 10여 년 전부터 250MW급 이상의 대용량 석탄IGCC 플랜트를 상업운전 하고 있으며, 일본과 중국을 비롯한 아시아에서도 대용량 플랜트를 시운전하고 있거나 건설 중에 있다. 한국에서는 제4차 전력수급계획에 의거 태안화력 부지 내에 300MW급 IGCC 플랜트 건설을 추진 중이며, 두산중공업은 '10년 상반기에 IGCC 가스화 플랜트에 대한 FEED 설계 (Front-Eng Engineering Design)를 완료하였다. 그 과정 중 설계조건에 의한 기본 엔지니어링 사항과 석탄 가스화 플랜트에 대한 성능예측 결과를 본 연구에서 소개한다. 가스화 플랜트의 엔지니어링은 가스화 블록과 가스정제 블록으로 구분하여 수행하였다. Process Data를 이용하여 PFD Development, P&ID Generation, Equipment Specification 개발, HAZOP 수행, Architecture Engineering 등의 순으로 FEED 설계를 진행하였다. BOD (Basis of Design)를 기준으로 운전조건별 Heat & Mass Balance와 Process Flow를 재검토하고 각 기기별 운전개념을 반영하여 P&ID를 개발하였다. 그리고 배관, 전기 및 제어에 대한 각종 Diagram 개발과 HSE (Health, Safety and Environment) 관련 설계를 수행하였다. IGCC 1호기의 엔지니어링 수행과 함께 Next 호기 자체설계 역량 확보를 위해 두산중공업은 'DIGITs'로 명명된 개념기본설계 Tool을 개발하고 있다. DIGITs는 공정모델링, 단위기기 개념설계, 공정구성 (Process Configuration) 및 종합 Database Package 형태로 구성된다. DIGITs에 의한 계산 결과 공정사 Process Data 기준시 가스화 블록 출구에서 Syngas HHV와 Syngas 현열은 각각 약 $636MW_{th}$와 약 $18MW_{th}$로, Plant 설계조건 $630MW_{th}$를 만족하는 것으로 예측되었다. 향후 DIGITs는 가스정제 블록 및 주변 BOP 설비 등과 연계한 종합 개념기본설계 Tool로써 개발 진행 중이다.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.2
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• pp.185-191
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• 2012

Typically, a wedge is involved to generate effectively high inspection angle in pipe weld inspection using phased array ultrasonic technique. But the usage of this wedge for weld or access limited area can cause coverage limitation for the examination volume because of the wedge front length. Therefore, the shear wave phased array probe which can generate high inspection angle without wedge is essentially necessary. In this paper, the shear wave phased array ultrasonic probe which can generate high inspection angle designed by modeling and manufactured from the modelling result. And this shear wave probe tested whether it can detect and sizing for EDM test block that contains various depth. As results, the experimental results show that the designed shear wave phased array probe can detect and size with reliable accuracy. Therefore if this phased array probe apply in field inspection, it is expected that it show more reliable inspection result for plant structure having access limitation.

• Journal of the Korean Institute of Gas
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• v.5 no.3 s.15
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• pp.1-8
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• 2001

This study was carried out for the purpose of determination of maintenance period and investigation of weak point due to freeze when the gas heater of KOGAS valve station Is not operated in winter season. 3-dimensional non-linear numerical simulation was conducted in order to predict the time and location which bath water in heater reaches to ice point. FLUENT V 5.0, commercial code, is used for thermal fluid flow analysis. We thought this was problem of heat conduction solving the energy equation and modeled gas heater by using the real geometry and scale for performing the 3-dimensional simulation. It was analyzed complex heat transfer phenomena considering convection due to air on surface, conduction in insulation material, natural convection of liquid in heater and heat loss through the pipe.

• Journal of Aerospace System Engineering
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• v.17 no.4
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• pp.28-33
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• 2023

In this study, computational fluid dynamics was used to analyze the flow bias generated as air supplied by a fan passes through ducts, piping, and a coal separation screen. The flow bias of the air flow is mostly caused by the spatial characteristics of the fan volute and duct, and the internal baffle and the coal separation screen at the outlet cause strong pressure losses that dampen the flow bias. ANSYS CFX was used for computational fluid dynamics, and since the baffle and the coal separation screen are shaped like perforated plates with many small holes uniformly distributed, actual modeling for analysis was not possible. Therefore, the Porous Loss Model was applied. The evaluation of the flow bias was analyzed based on the velocity distribution of the Porous Loss Model at the outlet surface of the coal separation screen obtained from the computational fluid dynamics results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.4
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• pp.397-406
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• 2016

Diverse stakeholders engaged in design, construction, and operation and maintenance of offshore plants typically operate heterogeneous plant 3D CAD systems. Engineering, procurement, and construction (EPC) companies are required to submit plant design result to the owner in the form of a plant 3D CAD model, as specified in the contract. However, because of the limitations of data interface of plant 3D CAD systems, EPC companies frequently perform manual remodeling to fulfill the terms and conditions of the contract. Therefore, comparison should be performed between the source plant 3D CAD model and the remodeled plant 3D CAD model to prove the validity of the remodeled plant 3D CAD model. To automate the comparison process, we have developed a system for quantitatively assessing the similarity of the plant 3D CAD models. This paper presents the architecture and detailed functions of the system. In addition, experimental results using this system are explained.

• Fire Science and Engineering
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• v.27 no.6
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• pp.1-7
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• 2013

In this study, the effects of various disk shapes of hydrant on the pressure drop are experimentally and numerically analyzed. The test methods for measuring pressure drop of hydrant are comply with standard of Underwriters Laboratory (UL). The hydrant as used in this study has one inlet, diameter 150 mm, and three outlet, 114.3 mm diameter for one outlet and 63.5 mm diameter for the others. The pressure of the hydrant are measured in the range 760 L/min~2,270 L/min for 63.5 mm outlet and 3,030 L/min~6,060 L/min for 114.3 mm outlet. Also, the numerical results of pressure drop are compared with the experiments to verify the accuracy and to analyze the of various valve shape of hydrant on the pressure drop. The engineering parameters, flow coefficients, are reduced from 181.57 to 136.35 ($L/min/kPa^{0.5}$) with inclined angle of disk from $0^{\circ}$ to $45^{\circ}$. These results are able to practical use for design hydrant to minimize pressure drop.