• Journal of the Korean Society of Safety
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• v.39 no.1
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• pp.27-32
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• 2024

This study analyzed cases of hydrogen (H₂) and natural gas (CH₄) leakage from a hydrogen-blended natural gas pipeline to determine a range of leakage characteristics, including leakage type, pipe material, pipe diameter, pressure, and damage size. Based on the results of this analysis, five hydrogen-blended natural gas leakage scenarios were selected. The national vision for a carbon-neutral society by 2050 is a very important strategic objective and promotes environmentally sustainable economic development in the age of the climate crisis. Accordingly, zero-carbon and low-carbon policies are being promoted in various fields, including energy production, consumption, and industrial processes. Hydrogen-blended natural gas is eco-friendly and is considered an important step towards carbon neutrality, with various countries including the United States and several European countries conducting empirical research to further investigate its potential. In Korea, a national research project commenced in April 2023 to verify and demonstrate the life cycle safety of blending hydrogen into the natural gas network. The results of this study will provide important data for the analysis of the damage impacts caused by the leakage of hydrogen-blended natural gas, such as the diffusion of gas clouds, fires, and gas explosions.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.5
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• pp.495-508
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• 2010

The aim of this study is to develop a quantified water loss Index to evaluate and manage leakage scientifically for the reduction of non-revenue water in water distribution systems. For the purpose, unavoidable background leakage suggested from UK water industry and IWA, and allowable water leakage in accord with the concept of allowable water loss are proposed by analyzing the inflow into two study water districts and the short-term water use of each customer in the districts. The study distribution areas are selected among the metered districts with good maintenance of leakage after improvement activities in Nonsan, medium sized city in Korea. Estimation models of allowable leakage are developed by metering and analyzing the minimum night flow at residential and commercial areas in the city. In the results of the investigation, it is estimated that background night flow in residential area was larger than that of commercial area where the types of business shows small water use characteristics. Meanwhile, night flow and background water loss on internal plumbing systems show great differences for each district which is influenced much by the water use characteristics and facilities scale. Based on metering water use data in various districts, leakage management criteria can be established under the consideration of domestic conditions in Korea by analyzing separated real water use and background leakage and it is possible to apply into presentation of optimal leakage level and reasonable time for working activities for leakage reduction.

• Convergence Security Journal
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• v.15 no.7
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• pp.39-45
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• 2015

Industrial secrets that companies own recently protected by various act related industrial security such as Trade Secret Act, Act on Prevention of Divulgence and Protection of Industrial Technology, etc. However, despite such protection infringement and leakage accidents of industrial secrets is increasing every year. According to a survey conducted by KAITS(Korean Association for Industrial Technology Security) annual average of estimated damage by industrial secrets leakage is estimated to be "50 trillion won." This is equivalent to the amount of annual revenue of small businesses more than 4,700 units. Following this, industrial secrets leakage causes serious damages to competitiveness of nation and companies and economic. However investment and effort to the industrial secrets leakage crime is lack of level compared to the scale of damage. Actually, most companies except some major companies are lack of response action about industrial secrets leakage because of shortage of separate organization, workforce, budget for industrial secrets leakage security. This paper aims to understand the overall flow of the industrial secrets leakage crime through various taxonomy such as cause of occurrence and leakage pathway and grasp the condition of damage from industrial secrets leakage through analyzation of internal and external industrial secrets leakage crime. This is expected to be the basis for related research.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.143-148
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• 2003

This study was experimentally performed in order to estimate the errors due to the leakage of transmitter gaugelines in the orifice flow meter for natural gas. It would be a serious problem in safety if a large quantity of leak was occurred at the tubes or fittings like valve. But in most cases the safety problems might be rarely happened because the gas leak detectors could be operated in advance and the various kinds of inspection would be also fulfilled periodically. If the leakage was occurred continuously with an undetectable amount at the gaugelines for measuring the pressure or the differential pressure(DP), the amount of leakage might be an error or an unaccounted flow(UAE). In addition if the measuring value of pressure or DP were affected by the leakage, it might also be a measurement error. The experiments were performed to estimate the amount of leakage and to check the DP changes if it exited. First, through the measurement of the air pressure changes in the airtight container connected to a transmitter with gaugelines as the time passed, the amount of leakage causing from the fittings of gaugelines was roughly estimated. As changing the leak position of the gaugeline, the leak was intentionally made to break out. The variance of DP was checked as controlling the extent of leakage and compared to no leak conditions. Consequently, under the normal maintenance conditions, the result represented that the amount of leakage causing from the gaugelines was insignificant and also the DP changes on leakage conditions were too small to cause the errors of measurements.

• Convergence Security Journal
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• v.19 no.2
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• pp.3-9
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• 2019

Most of security countermeasures have been implemented to cope with continuous increase leakage of technology, but almost security countermeasures are focused on securing the boundary between inside and outside. This is effective for detecting and responding to attacks from the outside, but it is vulnerable to internal security incidents. In order to prevent internal leakage effectively, this study identifies activities corresponding to technology leakage activities and designes technology leakage activity detection items. As a design method, we analyzed the existing technology leakage detection methods based on the previous research and analyzed the technology leakage cases from the viewpoint of technology leakage activities. Through the statistical analysis, the items of detection of the technology leakage outcomes were verified to be appropriate, valid and reliable. Based on the results of this study, it is expected that it will be a basis for designing the technology leaking scenarios based on future research and leaking experiences.

• Journal of Korea Water Resources Association
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• v.56 no.5
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• pp.347-356
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• 2023

In Water Distribution Systems (WDSs), can abnormal hydraulic and water quality conditions such as red-water phenomenon and leakage occur. To restore them, data is generated through various meters data to predict and detect. However, in the case of leakage if difficult to detect unless direct exploration is performed. Among them, unreported leakage, are not seen visually and account for the most considerable volumes of leakage, which leads to economic loss. Bur direct exploration is limited through on site conditions such as securing professional manpower. In this paper, leakage volumes and location were randomly generated for the WDS, which was assumed to be calibrated, and it was detected through a deep learning model. For abnormal data generation, the leakage was simulated using the emitter coefficient, and leakage detection was successfully performed through the generated abnormal data and normal data.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.197-202
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• 2003

The leakage quantity through concrete facing of Concrete Face Rockfill Dam(CFRD) is very small due to its low permeability of intact concrete. Even though the concrete facing is well designed and constructed, fine cracks can be generated due to effects of thermal and drying shrinkage. Therefore, it can be said that the leakage from the CFRD is subjected to not permeability of intact concrete but poor joints, cracks and foundation rocks. The Safety of a dam on leakage was evaluated based on the comparison between apparent permeability estimated and leakage quantity measured. The above method can be concluded to give a good direction for the evaluation of safety on CFRD in maintenance aspects as design and construction technology is improved with the accumulation of leakage data.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.5
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• pp.1-8
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• 2011

This paper proposes a new input pattern generator for minimal leakage power in the nanometer CMOS technology considering all the leakage current components (sub-threshold leakage, gate tunneling leakage, band-to-band tunneling leakage). Using the accurate macro-model, a heuristic algorithm is developed to generate a input pattern for the minimum leakage. The algorithm applies to ISCAS85 benchmark circuits, and the results are compared with the results of Hspice. The simulation result shows that our method's accuracy is within a 5% difference of the Hspice simulation results. In addition, the simulation time of our method is far faster than that of the Hspice simulation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.148-148
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• 2009

In order to investigate the quality in compliance with an electric leakage electric current from the electric leakage area after conferring the electric leakage environment in compliance with a flooding when the electric leakage electric current exists in the surface, it investigated the electric leakage electric current quality from the electric current distribution and flooded districts from the present paper. At the result, we have known that flux density is constant regardless of distance variation.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.561-564
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• 2007

This case was successfully constructed as a leakage prevention case of primary 2-arch tunnel located in Anyang, Gyungkido. The leakage of primary 2-arch tunnel was observed at middle wall of tunnel and girder of tunnel. Such a leakage of primary 2-arch tunnel generally occurred due to the damage of the waterproof membrane constructed on the middle wall during the blasting works of right and left tunnel after construction of the middle wall. As the leakage, icicles hanged from girder of tunnel in the winter. In such phenomenon, the risk of the traffic accident in the tunnel was high. In this case, leakage prevention works were successfully constructed using the heat insulated drainage.