• Journal of the Korean Institute of Gas
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• v.6 no.1 s.17
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• pp.17-23
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• 2002

This paper introduces the spring-mounted odometer system which maintains the correct contact with the pipe wall and measures the distance along the pipe. The odometer wheel is designed to keep contact to the pipelines inner wall and to generate fifty rectangular pulses per one turn(159.5681mm) during pigging. The pipeline has the defects in various types such as buckles, winkles, cracks, dents, welding point and so on. Specially girth welding points which exist each 12m of the pipeline, much affects the operational environment of the odometer. The measurement error of the distance along the pipe is accumulated, for the measurement error of wheel's circumference and the pipeline inner environment. So, this paper proposes the method for the error compensation based on the analysis of the odometer's behavior around the girth welding point of pipe. The experimental results show that developed odometer system can be used for the intelligent pig with good performances.

• Journal of the Korean Institute of Gas
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• v.12 no.2
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• pp.25-31
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• 2008

Recently risk management based on a quantitative assessment is considered to improve the level of safety in Korea. This paper focuses on the procedure of the quantitative risk assessment for natural gas pipelines. For that purpose, the methods to estimate failure frequency based on failure causes from European Gas Pipeline Incident Data Group and BG Transco, to analyze consequence caused by fire, and to calculate individual risk and societal risk have been proposed systematically in this paper. Risk criteria of individual risk and societal risk have been proposed by considering the environment of pipeline route in Korea. The proposed procedure of quantitative risk assessment may be useful for risk management during the planning and building stages of a new pipeline, and modification of buried pipeline.

• Journal of the Korean Institute of Gas
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• v.12 no.2
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• pp.92-98
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• 2008

A combination of the instrumented indentation and 3D morphology measurement has been tried in order to perform a real-time property measurement of degraded materials in gas pipelines; three-dimensional indent morphologies were recorded using a reflective laser scanner after a series of insturmented indentations on three metallic specimens. Dimensions of the permanent deformation zone and contact boundary were analyzed from the cross-sectional profile over an remnant indent and used for estimating yield strength and hardness, respectively. Estimated yield strength was comparable with that from uniaxial tensile test and actual hardness implying material pile-up effects was lower than the calculated value from indentation curve by $20{\sim}30%$. It means that this 3D image analysis can explain the material pile-up effects on the contact properties. Additionally, a combined system of indentation and laser sensor was newly designed by modifying a shape of the indentation loading fixture.

• Journal of the Korean Institute of Gas
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• v.18 no.5
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• pp.26-32
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• 2014

CCS(Carbon Capture and Storage) which is technic to capture and storage the carbon-dioxide is the method that reduces the carbon-dioxide from the industries to prevent earth from the global warming. In order to apply to the practical site, it is inevitable to investigate the possibility of damage in the pipe or components by carbon-dioxide. In this paper, the immersion test is performed to estimate the suitability of the rubber which is used to seal or connect the pipelines because the rubber has not been validated. Also, the immersion test is carried out in a certain condition(pre- and supercritical state).

• Journal of the Korean Institute of Gas
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• v.21 no.1
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• pp.72-79
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• 2017

The operating temperature range of the natural gas pipeline in Arctic environment would be controlled primarily to optimize gas throughput and to minimize the environmental impact resulting from operation of such pipelines. The temperature of the gas as it flows through the pipeline is a function of both the Joule-Thomson effect and the pipe to soil heat transfer. Therefore, the heat transfer and Joule-Thomson effect of the buried natural gas pipeline in this study were carefully considered. Soil temperatures and overall heat transfer coefficients were assumed to be $0{\sim}-20^{\circ}C$ and $0{\sim}5.5W/m^2K$, respectively. The gas temperature and pressure calculations along a pipeline were performed simultaneously at different soil temperatures and overall heat transfer coefficients. Also, this study predicted the phase change and hydrate formation for different soil temperatures and overall heat transfer coefficients using HYSYS simulation package.

• Journal of Ocean Engineering and Technology
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• v.34 no.5
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• pp.361-370
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• 2020

We developed a heavy-duty work class ROV trencher named URI-T (Underwater robot it's trencher) that can conduct burial and maintenance tasks for underwater cables and small diameter pipelines. It requires various supporting systems, including a dynamic positioning (DP) vessel, launch and recovery system (LARS), A-frame, and winch in order to perform burial tasks because of its dimensions (6.5 m × 5.0 m × 4.5 m, 20 t) and the tough working environment. However, operating a DP vessel has disadvantages as it is expensive to rent and operate and it is difficult to adjust the working schedule for some domestic coast construction cases. In this paper, we propose a method using a barge instead of a DP vessel to avoid the above disadvantages. Although burying the cable and pipeline using a barge has lower working efficiency than a DP vessel, it can save construction expenses and does not require a large crew. The proposed method was applied over two months at the construction of the water supply in Yokji-do, and the results were verified.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.4
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• pp.61-67
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• 2018

High-frequency signals are analyzed at the inlet/outlet pipeline and pump casing during cavitation tests of the LOx pump for liquid rocket engines. Root-mean square values of all data are investigated with respect to cavitation number. The values of synchronous, harmonic, and cavitation instability frequencies are also calculated. Pressure pulsations of the inlet and outlet pipelines are affected by cavitation instabilities. The 3x component (i.e., the blade-passing frequency of the inducer) is predominant in the outlet pulsation sensor. This seems to be related to the fact that the number of impeller blades is a multiple of the number of the inducer blades. The cavitation instability is also measured at the accelerometer of the pump casing.

• Proceedings of KOSOMES biannual meeting
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• 2008.05a
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• pp.177-180
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• 2008

Based on Latti(1974) and Jacobs&Way(1968)'s theory, we estimate the coastal area of Jeju and Busan cities. According to the estimateio, The seawater pumping line causes the problem of coastal landscape. Water management treatment of coastal region has been an important problem in Jeju city and Busan city since the distributions of pipeline if the pumping system made a bad view in coastal region. To solve the problem, we observed the pipelines that are on the surface around the coastal region we proposed two methods, that is, one is a short time treatment, the other is a long time one. The short is based on the colour treatment, which is pipeline colour changing into surround natural one. The long time is the construction plan design method. Although the later method was very useful in Jeju island. However, it takes a lot of time and money. Therefore, in the situation, the short time is the better than the long time one.

• Journal of IKEEE
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• v.25 no.3
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• pp.479-484
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• 2021

This paper proposed and designed a structure to achieve high performance with a small number of cores in GPGPU with SIMT structure. GPGPU for application to mobile devices requires a structure to increase performance compared to power consumption. In order to reduce power consumption, the number of cores decreased, but to improve performance, the size of the warp scheduler for managing threads was set to 4, which was greatly reduced than 32 of general GPGPU. Reducing warp size can reduce the number of idle cycles in pipelines and efficiently apply memory latency to reduce miss penalty when accessing cache memory. The designed GPGPU measured computational performance using a test program that includes floating point operations and measured power consumption through a 28nm CMOS process to obtain 104.5GFlops/Watt as a performance per power. The results of this paper showed about four times better performance per power compared to Tegra K1 of Nvidia

• Genomics & Informatics
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• v.19 no.1
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• pp.6.1-6.10
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• 2021

Vascular endothelial growth factor (VEGF) is expressed at elevated levels by most cancer cells, which can stimulate vascular endothelial cell growth, survival, proliferation as well as trigger angiogenesis modulated by VEGF and VEGFR (a tyrosine kinase receptor) signaling. The angiogenic effects of the VEGF family are thought to be primarily mediated through the interaction of VEGF with VEGFR-2. Targeting this signaling molecule and its receptor is a novel approach for blocking angiogenesis. In recent years virtual high throughput screening has emerged as a widely accepted powerful technique in the identification of novel and diverse leads. The high resolution X-ray structure of VEGF has paved the way to introduce new small molecular inhibitors by structure-based virtual screening. In this study using different alkaloid molecules as potential novel inhibitors of VEGF, we proposed three alkaloid candidates for inhibiting VEGF and VEGFR mediated angiogenesis. As these three alkaloid compounds exhibited high scoring functions, which also highlights their high binding ability, it is evident that these alkaloids can be taken to further drug development pipelines for use as novel lead compounds to design new and effective drugs against cancer.