• Journal of the Korean Geotechnical Society
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• v.30 no.9
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• pp.57-66
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• 2014

The ground in cold region consists of active and permafrost layers. The active layer at the unstable state may cause ground corrosion and uplift, when the temperature of frozen ground increases due to seasonal changes. The thermosyphon is one of the stabilization methods to maintain the ground stability in the frozen ground. The thermosyphon is a closed two-phase convection device that extracts heat from the ground and discharges it into the atmosphere. In this study, ground freezing experiment using a thermosyphon and simulated ground with the isolation material was conducted to evaluate the thermal performance of the thermosyphon. In order to consider the thermal performance of the thermosyphon, commercial numerical program (TEMP/W) was adopted. Likewise, the thermal performance of thermosyphon and thermal properties of ground were applied in the numerical model. In a series of comparisons with experiment results and numerical study, thermal performance of thermosyphon can be evaluated.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.2
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• pp.189-195
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• 1997

To cope with increasing importance of water stress in food crop production, characteristics and cultivar differences in physiological responses of winter barley plants to water stress during seedling stage were studied employing three covered-barley, Milyang 12, Durubori, and Olbori, one naked-barley, Baekdong, and one two-row beer-barley, Hyangmaeg. Water stress was given to barley plants by withholding watering in soil-culture pots or by adding P.E.G. (polyethylene glycol, M. W. 4,000) to the nutrient culture solution. When water stress was imposed by withholding watering for 10 days to the seedlings grown in pot-soil for 10 days after emergence, leaf water potential of 5 cultivars was decreased almost to the same degree, from control -3.5 bar to the water stressed -26.6 bar. However, growth and some physiological responses were differently affected by cultivars: The plant height was decreased by 16-26％ : seedling dry weight by 25∼42％ ; chlorophyll content by 21∼39％ ; second leaf survival rate by 8∼18％ ; and free proline content per gram of leaf dry weight was increased from control 0.2∼0.5mg to the water stressed 5.8∼13.2mg. Drought resistances of 5 barley cultivars, based on the leaf survival rate and the decreased rate in seedling dry weight at the end of stress treatment, were high in the order of 3 covered-barley＞naked-barley＞two-row barley.

• Korean Journal of Heritage: History & Science
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• v.47 no.3
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• pp.4-23
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• 2014

Seokjojeon Hall is the Neoclassic style building situated in Deoksugung Palace, which was proposed by John McLeavy Brown who was a chief commissioner of the Daehan Empire and designed by John Reginald Hardings in 1897. Construction of the Seokjojeon Hall began in 1900 and completed in 1910 at the total cost of one million won. Decorating and furnishing of the interior was designed by Lovell and all the furniture of Seokjojeon Hall had been purchased from Maple&Co. The Maple&Co was the supplier of luxury furnitures and decorating items for luxurious residentials, hotels, embassies and the palaces and its headquarter was located in London. Ready-made furnitures were purchased as shown in the Maple's catalog. The designs and styles of the west were applied to Seokjojeon Hall. That is one of the aspects showing Daehan Imperial underwent a period of Westernization.

• Journal of the Korean Geosynthetics Society
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• v.18 no.3
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• pp.11-22
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• 2019

This study was conducted to identify the causes of the unusually high number of rock slope failures during an expressway construction in Yangsan fault system. The shear strength (cohesion and internal friction angle) of 128 slopes of discontinuities including bedding, joint, and fault planes were re-evaluated through the examination of face mapping and back analysis. The re-evaluated values were analyzed and then compared with the existing data and values used in the design. As a result, the re-evaluated cohesion and friction angles were very low compared to the existing data and the values applied in the design. This incongruity was pointed as the primary reason for the rock slopes failures during the construction. This may be related to the inherent features of clastic sedimentary rocks in the study area, and the discontinuities in the sedimentary rocks in this region played a significant role. Especially, bedding discontinuity showed a big difference compared to the existing data. The shear strength depended on the type of discontinuity in case of clay filled in discontinuity. However, shear strength was independent on the type of discontinuity in case of shattered materials filled in discontinuity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.1819-1824
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• 2014

The vacuum-glazing panel is a panel that keeps two glasses completely sealed in a vacuum condition. It is the high function insulation material of having the wall level minimizing the heat loss by the conduction and convection heat transmission coefficient. The edge sealing is a very important process of vacuum glass on the strength, thickness and air tightness. In this study, by using the hydrogen mixture gas torch, two sheets of glass was sealing in the furnace. The thickness and strength of the glass according to the process parameters is measurement and analysis, and predicting the edge sealing strength of glass by using taguchi method of experiment. We verified the validity of the experiment by checking the error rate through additional experiment.

• Korean Journal of Ichthyology
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• v.4 no.1
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• pp.54-79
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• 1992

Thirty six species belonging to 21 genera in the family Cottidae from Korea are reviewed and provisional keys to species and genera are provided. Synonyms based on Korean references are included for all cottid fishes of korea, and their taxonomic positions and distribution are discussed. Specimens of twenty one species of this family were collected by trawlers from 38 localities during 1989 to 1992. Five cottid species are recorded for the first time in Korea : They are Triglops jordani(Schmidt), Myoxocephalus stelleri Tilesius, Taurocottus bergi Solatov et Pavlenko, Icelus ochotensis Schmidt and Pseudoblennius zonostigma Jordan et Starks. It is noticeable that most cottid fishes of Korea except 3 species are distributed along the northeastern coast at the southern extremity of cold current from the Okhotsk Sea.

• The KSFM Journal of Fluid Machinery
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• v.4 no.1 s.10
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• pp.7-13
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• 2001

In developing a multistage compressor, the stage matching is one of the critical design issues. The mismatching can be often observed even if each stage has been proven good and then used as part of a compression system. A good matching among the stages can be achieved by changing various design parameters (i.e., passage cross sectional areas, blades angles, stagger angles, curvature, solidity, etc.). Therefore, designers need to find out what parameters must be changed and how much. In this study, a method to search the design parameters for optimum stage matching has been used based on an 1-D mathematical model of a compressor, which uses the data obtained from the preliminary test to identify the design parameters. This methodology is applied with a two-stage axial compressor, which was originally designed for a helicopter gas turbine engine. After identifying design parameters using preliminary test data, an optimization process has been employed to achieve the best matching between the stages (i.e., maximum efficiency of the compressor at its operation modes within a given range of the rotor speed under given restrictions for required stall margins and mass flow). 3-D flow calculations have been performed to confirm the usefulness of the corrections based on the 1-D mathematical model. Calculational results agree well with the experimental data in view of the performance characteristics. Some promising results were produced through the methodology proposed in this paper in conjunction with flow calculations.

• Clinical and Experimental Pediatrics
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• v.48 no.6
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• pp.655-659
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• 2005

Esophageal duplication cysts are rare congenital lesions that occur as a result of a failure in the tubulation of the esophagus. They are most frequently single, tubular, or cystic. They may cause compressive symptoms or may be discovered incidentally on chest radiographs. They become symptomatic when complications develop. Symptoms often are related to the location of the duplication; esophageal lesions can create respiratory difficulties. The definitive diagnosis of esophageal duplication cysts requires the pathological evaluation of the cyst after surgical removal. We experienced a rare tubular esophageal duplication, in a 2-month old girl who presented with fever and grunting. This is the first reported case in which the sequence of events of ruptured tubular esophageal duplication with empyema, mediastinitis and aneurysm occured.

• Journal of Digital Convergence
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• v.15 no.6
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• pp.391-398
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• 2017

In this paper, we compared the performance of "Network Intrusion Detection System based on attack feature selection using fuzzy control language"[1] and "Intelligent Intrusion Detection System Model for attack classification using RNN"[2]. In this paper, we compare the intrusion detection performance of two techniques using KDD CUP 99 dataset. The KDD 99 dataset contains data sets for training and test data sets that can detect existing intrusions through training. There are also data that can test whether training data and the types of intrusions that are not present in the test data can be detected. We compared two papers showing good intrusion detection performance in training and test data. In the comparative paper, there is a lack of performance to detect intrusions that exist but have no existing intrusion detection capability. Among the attack types, DoS, Probe, and R2L have high detection rate using fuzzy and U2L has a high detection rate using RNN.

• Journal of the Korean Geosynthetics Society
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• v.10 no.2
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• pp.13-19
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• 2011

Precast culvert system is generally constructed with a series of process such as excavation, ground mitigation, placement of culverts, anti-leakage packing between adjacent culverts, post-tensioning for PS strands and backfilling. In this process inappropriate ground mitigation often causes differential settlement and, correspondingly, makes water-leakage to be occurred between adjacent boxes. This study was performed to understand the behavioral characteristics of recently proposed precast foundation plate to support precast culvert system through on-site pilot construction. The gap between two adjacent culverts, increment of earth pressure at the bottom of culvert, vertical settlement of top of the culverts were monitored using various sensors. The monitoring results showed that the proposed foundation plate provides better culvert system in the points of less gap development, earth pressure and settlement at the adjacent of two culverts.