• Proceedings of the KSME Conference
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• 2003.11a
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• pp.187-192
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• 2003

The heat (mass) transfer characteristics in the tip-leakage flow region of a high-turning first-stage turbine rotor blade has been investigated by employing the naphthalene sublimation technique. The heat transfer data in the tip-leakage flow area for the tip clearance-to-span ratio, h/s, of 2.0% are compared with those in endwall three-dimensional flow region without tip clearance (h/s = 0.0 %). The result shows that the thermal load in the tip-leakage flow region for h/s = 2.0% is more severe than that in the endwall flow region for h/s = 0.0%. The thermal loads even at the leading and trailing edges for h/s = 2.0% are found larger than those for h/s = 0.0%. The tip-leakage flow results in heat transfer augmentations near the tip on both pressure and suction sides in comparison with the mid-span results.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.73-74
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• 2017

Below-grade concrete structure in residential buildings are exposed to various cracking conditions in between installation, construction and usage. Leakage follows the cracks along the exterior wall and floor slabs, and leakage occurring in this conditioning brings about discomfort to the users inside the building. This study analyzes a survey on the causes of leakage in below-grade concrete structure and proposes a solution method.

• The Journal of the Korean dental association
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• v.22 no.4 s.179
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• pp.313-322
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• 1984

This study was designed to observe the marginal leakage of three permanent cements affected by three temporary cements. The temporary cements used in this study were Zinc oxide-eugenol, Non-eugenol, and Calcium hydroxide cements and the permanent cements were Zinc phosphate, Polycarboxylate and Alumina reinforced EBA cements. To measure the dye penetration into permanently cemented zone, the experimental specimens were treated with the temporary cements for a week. An analysis of the data obtained from 120 specimens resulted in the following conclusions: 1. Regardless of the types of the permanent cements used, using Calcium hydroxide cement as temporary cement showed higher marginal leakage than other temporary cements. 2. Using Polycarboxylate cement as permanent cement showed less marginal leakage than other permanent cements. 3. The marginal leakage in zinc phosphate cement was similar to Alumina reinforced EBA cement regardless of the types of the temporary cements.

• Journal of Digital Convergence
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• v.14 no.11
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• pp.45-51
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• 2016

Although the problem of personal data leakage is reported to be serious, there has been no research that tries to excavate out that real cause of the leakage in scientific prospective. Although this topic is considered to be crucial, there have been no literatures relevant to the topic, and the reason for this limitation is that scientific approach to this problem was not feasible. In this respect, in this paper a model for such scientific analysis and a methodology of analysis have been devised. Results show that the degree of rigidity turns out be the determinant that vindicates the degree of leakage. The notion of data rigidity is revealed to be very strongly correlated to the number of hacking incidents in each country. The notion of resident data freedom was then deployed in this paper to determine the world-wide ranking for a slew of different countries. The United Kingdom and the Republic of Korea turned out to be the two extreme countries that lie in the spectrum of the scale, with UK the most flexible and ROK one of the most rigid.

• Convergence Security Journal
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• v.18 no.5_1
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• pp.121-126
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• 2018

The development of modern ICT and network technologies has made the business environment smart.and under such circumstances, a great deal of data is being generated, stored and used. The important information that becomes an energy source for corporate management creates economic profit and value and is also utilized as a basis for strong influence. Therefore, important information must ensure its availability and convenience while ensuring confidentiality and integrity, which is the basic objective of information protection. However, most companies are seeing more and more incidents of serious damage due to the leakage of important internal information. In this study, we deal with the Data Loss Prevention (DLP) technologies and solutions to prevent internal information leakage and establish stable data security and information protection management.

• Journal of the Korea Convergence Society
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• v.13 no.3
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• pp.33-41
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• 2022

In this article, we proposed to predict natural gas (NG) leakage levels through feature selection based on a factor analysis (FA) of the integrating the Korean Meteorological Agency data and natural gas leakage data for considering complex factors. The paper has been divided into three modules. First, we filled missing data based on the linear interpolation method on the integrated data set, and selected essential features using FA with OrdinalEncoder (OE)-based normalization. The dataset is labeled by K-means clustering. The final module uses four algorithms, K-nearest neighbors (KNN), decision tree (DT), random forest (RF), Naive Bayes (NB), to predict gas leakage levels. The proposed method is evaluated by the accuracy, area under the ROC curve (AUC), and mean standard error (MSE). The test results indicate that the OrdinalEncoder-Factor analysis (OE-F)-based classification method has improved successfully. Moreover, OE-F-based KNN (OE-F-KNN) showed the best performance by giving 95.20% accuracy, an AUC of 96.13%, and an MSE of 0.031.

• The Journal of Society for e-Business Studies
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• v.19 no.3
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• pp.65-89
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• 2014

Although many studies have focused on the influences and outcomes of personal information leakage, few studies have investigated how the personal information leakage prevention behavior differs depending on internet user. This study attempts to supplement the existing studies' limitations with the use of risk perception attitude (RPA) framework. More specifically, this study tries to show internet user can be classified into four groups based on perceived risk of personal information leakage and efficacy beliefs of personal information protection, and to identify how the groups differ in terms of motivation, information seeking, and behaviors for privacy leakage prevention. Analysis on survey data from 276 internet users reveals that the users can be classified into responsive, avoidance, proactive, indifference groups. Furthermore, there are differences between groups in terms of motivation, information seeking, and behaviors for personal information leakage prevention. This study contributes to expand existing literature by providing tailored guidelines for implementation of personal information protection strategies and policy.

• Geophysics and Geophysical Exploration
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• v.19 no.4
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• pp.200-211
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• 2016

To support cross potential array and direct potential array, the array for leakage detection of all kinds of water facilities is proposed and it is named as the D-Lux array. The D-Lux array data are arranged to a coloured matrix and it is called the D-Lux view. Low potential difference of anomalous zone shown in D-Lux view implies the indication of leakage zone. Furthermore, for an intuitive interpretation of D-Lux array, equipotential distribution map is made by using D-Lux and direct potential array data. Equipotential distribution map makes us possible to predict import point, export point and the path of water leakage that we could have not anticipated in D-Lux view and the graphs. The water tank experiment and numerical analysis were carried out as preparatory experiment and the field explorations were conducted at a concrete weir and a fill dam. As a result, effective and specific detection of leakage path was possible for the concrete weir and the fill dam.

• Convergence Security Journal
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• v.17 no.5
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• pp.101-110
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• 2017

The purpose of this study is to examine possibilities of industry secret information leakage through IoT devices and to prevent information leakage from the perspective of administrative and technique security. From the administrative security perspective, first, it is important to face the possibility of industry information data leakage through anyone who can access companies and should establish guidelines to limit the use of IoT devices when entering companies. Second, security management guideline should be prepared by companies or upon user's request and use of any electronic devices sharing wireless internet connection should be eliminated or restricted. From technique security perspective, channels that sharing IoT devices in computers should be controlled since industry secret information are stored in computers and servers. Furthermore, IoT devices that accessing wireless internet network or devices that already registered should be regularly checked in order to minimize any information leakage. Lastly, data and information stored in computers and servers should be encrypted.

• Journal of Internet of Things and Convergence
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• v.10 no.2
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• pp.17-23
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• 2024

Losses in domestic water supply due to leaks are very large, such as fractures and defects in pipelines. Therefore, preventive measures to prevent water leakage are necessary. We propose the development of a leakage detection sensor utilizing vibration sensors and present an optimal leakage detection algorithm leveraging artificial intelligence. Vibrational sound data acquired from water pipelines undergo a preprocessing stage using FFT (Fast Fourier Transform), followed by leakage classification using an optimized tree-based boosting algorithm. Applying this method to approximately 260,000 experimental data points from various real-world scenarios resulted in a 97% accuracy, a 4% improvement over existing SVM(Support Vector Machine) methods. The processing speed also increased approximately 80 times, confirming its suitability for edge device applications.