• Journal of Conservation Science
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• v.27 no.2
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• pp.201-209
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• 2011

While consolidants based on tetraethoxysilane (TEOS) have been widely used for the consolidation of decaying stone heritages, TEOS-based consolidants suffer from practical drawbacks, such as crack formation of the gel during the drying phase due to the developed capillary force. We have prepared new TEOS-based consolidants containing flexible (3-glycidoxypropyl) trimethoxysilane (GPTMS) in order to reduce capillary force development during gel drying. In this study, we have prepared TEOS/GPTMS-based consolidants containing ETEOS in order to improve the surface hydrophobisity. The physical properties of the TEOS/GPTMS/ETEOS solution with different hydrolysis were compared with those of the commercial products Wacker OH$^{(R)}$. The contact angle of the surface increased with the addition of the ETEOS, which is higher than that of Wacker OH$^{(R)}$. The sol-gel mechanism was manipulated by the degree of hydrolysis as well as the amount of ETEOS. The properties and the applicability of the developed consolidants for the decayed Korean granites are also investigated.

• Journal of the Korean Geotechnical Society
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• v.36 no.7
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• pp.5-14
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• 2020

Kansai International Airport (KIX) was opened in September 1994. Although 26 years have passed since the completion of the first island, long-term settlement is still in progress. This settlement occurs in the Pleistocene layer. For it is not easy to determine the permeability of the Pleistocene sand layer because the thickness and the degree of fine content in the horizontal direction are constantly changing. In addition, it is also a difficult to predict the interactive behavior of the ground due to the construction of the second phase island adjacent to it. In order to solve this problem, a two-dimensional finite element analysis considering elasto-viscoplastic was performed to evaluate the long-term deformation, including the interactive behavior of the alternating Pleistocene foundation due to the construction of two adjacent reclaimed islands. In general, two-dimensional analysis can be used when a section can represent the entire sections. However, Kansai Airport is an artificial reclaimed island so two-dimensional analysis cannot solve the problem such as the stress deformation in the corners of the island. Additionally, the structure of the actual sub-ground through physical exploration is non-homogeneity and its thickness is also not constant. Therefore, there are limitations for the two-dimensional analysis to explain the phenomena. That is, three-dimensional analysis is strongly required. Due to these demands, the author extended the existing two-dimensional program capable of elasto-viscoplastic analysis to three-dimensional and completed the verification of the three-dimensional program developed through one-dimensional consolidation analysis. In order to demonstrate the validity of the developed 3D program that has been verified, an analysis is performed under the same analysis conditions as the existing research using a two-dimensional program. The effectiveness of the developed 3D numerical analysis program was demonstrated by comparing the analysis results with the 2D results and actual measurement data.

• Proceedings of the Korean Geotechical Society Conference
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• 1991.10a
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• pp.332-347
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• 1991

Accurate prediction of future settlement is essential for the settlement control of soft soil by pre-loading method. To predict future settlement in clayey soft soils, several methods like Asaoka method, Hyperbolic Method and Hoshino method are currently being used. These methods predict the future sett1ement by mathmatical treatment of the measured settlement data on the basis of consolidtion theory and empiricism. But the correlation coefficient between the measured and the predicted settlement was relatively low (0.8~0.9). Also, the prediction of future settlemet for the design load is very difficult. In this article, the measured field settlement data was treated as the the field consolidation test. Hence, condolidation coefficient(Cv) and compression index(Cc) was evaluated from the field settlement data. Cv and Cc values from field data was used to calculate the degree of consolidation and settlement at desired time. By this method, the correlation coefficent between the measured and the predicted settlement was significantly increased(0.97~0.99). Also the settlement by the design load after the improvement of soft soil could be predicted reasonably. This method is quite rational and sound but it requires thousands of calculation steps. Today, by the aid of low priced personal computers above mentioned technique could be used much acre economically and effectively than conventional methods. This article presented the mechanisms and capacities of this method and demonstrated the enhanced correlation coefficient when applied to actual field settlement data.

• Journal of the Korean GEO-environmental Society
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• v.6 no.2
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• pp.51-60
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• 2005

The disposal problem of waste lime which is a residual product of lime industry have caused a lots of arguments in the past few years. Further more, waste lime contains a high moisture content which causes the disposal of waste lime is a great difficulty. The purpose of this study is to investigate for the effective dewatering solutions by placing various prefabricated vertical drains. The moisture content and degree of consolidation, pore water pressure, changes of settlement, bearing capacity with various vertical drains in waste lime were analyzed. The laboratory test results indicate that PBD is 2 times higher than circular drain in coefficient of consolidation. Based on the laboratory test results, settlement, pore water pressure, and dewatering measurements are shown in similar tendency. It is considered that PBD can drain primitive pore water much efficiently. The picture of SEM shows that circular drain filter has a serious clogging problem in comparison with PBD. In conclusion, PBD holds a superiority in waste lime's ground improvement and dewatering pore water pressure from the waste lime sludge. Also, circular drain is desired for some modification in its filtering system.

• Geomechanics and Engineering
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• v.5 no.1
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• pp.17-36
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• 2013

Settlement of the piled raft can be estimated even after years of completing the construction of any structure over the foundation. This study is devoted to carry out numerical analysis by the finite element method of the consolidation settlement of piled rafts over clayey soils and detecting the dissipation of excess pore water pressure and its effect on bearing capacity of piled raft foundations. The ABAQUS computer program is used as a finite element tool and the soil is represented by the modified Drucker-Prager/cap model. Five different configurations of pile groups are simulated in the finite element analysis. It was found that the settlement beneath the piled raft foundation resulted from the dissipation of excess pore water pressure considerably affects the final settlement of the foundation, and enough attention should be paid to settlement variation with time. The settlement behavior of unpiled raft shows bowl shaped settlement profile with maximum at the center. The degree of curvature of the raft under vertical load increases with the decrease of the raft thickness. For the same vertical load, the differential settlement of raft of ($10{\times}10m$) size decreases by more than 90% when the raft thickness increased from 0.75 m to 1.5 m. The average load carried by piles depends on the number of piles in the group. The groups of ($2{\times}1$, $3{\times}1$, $2{\times}2$, $3{\times}2$, and $3{\times}3$) piles were found to carry about 24%, 32%, 42%, 58%, and 79% of the total vertical load. The distribution of load between piles becomes more uniform with the increase of raft thickness.

• Clinical and Experimental Pediatrics
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• v.45 no.4
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• pp.529-534
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• 2002

Interstitial pneumonia is a heterogenous group of inflammatory and fibrosing lesions that manifest themselves as infiltrative lung disease. Of these, nonspecific interstitial pneumonia is characterized as a variable degree of interstitial inflammation with or without fibrosis and is distinguished from usual interstitial pneumonia and desquamative interstitial pneumonia, histologically. The influx of inflammatory cells and the responses of immune effector cells injury to the alveolar wall and these initial injuries results in alveolitis and fibrosis. Consequently, the gas exchange throughout the alveolar wall is impaired and the patients suffer from lung diseases of a restrictive pattern. The chief complaints represented are dyspnea and dry cough. We experienced a case of nonspecific interstitial pneumonia in a 10-year old girl. The patient had been healthy and had not been exposed to organic dusts or other toxic materials. The pathology of lung biopsy tissue showed that the alveoli were thickened by a mixture of chronic inflammatory cells and collagen type fibrosis. High resolution computed tomography(HRCT) found the patchy areas of ground-glass opacity with patchy consolidation and irregular reticular opacity, and diffuse distribution without zonal predominance. The forced vital capicity(FVC) was 31%, forced expiratory volume in one second ($FEV_1$) 29% and $FEV_1/FVC$ 90%, so a restrictive pulmonary insufficiency was found.

• Fashion & Textile Research Journal
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• v.7 no.5
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• pp.509-518
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• 2005

In recent years retail competition has intensified, generally as a consequence of technologies, more sophisticated management practices and industry consolidation. An understanding of current customers' loyalty intentions and their determinants is an important basis for the identification of optimal retailer actions. The focus of this study is to examine the links between patronage intention and the effects of various antecedents of current customers' store loyalty intentions in fashion store. 340 female universities students living in Seoul were analyzed by utilizing multiple regressions to investigate the predictability of each of the 4 different sets of variables(consumer value, source of information, clothing benefits, importance of store attributes) on four patronage intentions of apparel shopping(discount store, speciality store, conventional market, Fashion shopping mall). Four factors were significant in predicting conventional market patronage intention. Brand had a negative coefficient, while price, social affiliation, store fashion service/promotion had positive coefficients. Fashion shopping mall were predicted by five factors:brand had a negative coefficient, while media, social affiliation, price, uniqueness had positive coefficients. For specialty store, four factors were significant: brand had a negative coefficient, while store fashion service/promotion, personal sources, uniqueness had positive coefficients. Four factors were significant in predicting discount store patronage intention :price, store fashion service/promotion, social affiliation, variety of price & product had positive coefficients. Despite the relatively low $r^2s$, all four variables appeared to have, to some degree, predictability of choosing among four different types of store for apparel shopping. Based on the results, patronage intention profiles for four retail stores were developed. Marketing implications are discussed.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.7
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• pp.1162-1174
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• 2010

Excavated gold brocade, often shows signs of serious damage and contamination from environmental factors such as exposure to soil or human remains. Therefore, most of the conservation procedures are focused on the consolidation of the gold thread and on cleaning with water or organic solvents. Indiscreet cleaning using solvents could damage the gold leaf, which identifies the features of fabric. There is a need to develop cleaning protocols appropriate for relics through the careful analysis of the condition of the relics. This study finds the appropriate cleaning method for the excavated gold brocade. Four different cleaning methods, vacuum cleaning, kneaded rubber eraser cleaning, immersion wet cleaning, and absorption wet cleaning were applied to the excavated gold brocade. The degree of cleaning and damage were examined depending on the cleaning methods, changes to the physical condition (before and after cleaning) were also analyzed through the surface observation. Although immersion cleaning showed the best cleaning result, this method had a risk of damage to the gold thread. Absorption wet cleaning safely eliminated the various soluble contaminants and the rotten smell of relics. Kneaded rubber eraser was suitable for the excavated gold brocade fabric because it can be applied to selective parts, intentionally excluding some sensitive parts such as the gold thread. The vacuum cleaning method required special attention because of a possibility of suctioning off loosely attached gold leaf. Dual cleaning, the kneaded rubber eraser cleaning, followed by the absorption cleaning was the most effective method to preserve and clean excavated gold brocade.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.6
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• pp.729-736
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• 2015

In this paper, It was performed to optimize for the deck's structural design of a double ended car ferry ship respect to Goal-Driven Optimization (GDO). It was examined for the strength and deformation of the deck and determined to save economic cost the optimal point. The deck thickness based on the Design of Experiments (DOE) and response surface method was increased to 110%. and can improve the deck's strength and stiffness. By performing the regression analysis respect to the result, we propose the optimal regression model formula as a third degree polynomial regression models. The coefficient of determination $R^2$ was about 0.98 and reliability could be obtained.

• Journal of the Korean GEO-environmental Society
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• v.4 no.4
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• pp.25-34
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• 2003

This paper is focused on an experimental study in order to investigate the utilization of sewage sludge ash as the cover and liner materials for the waste disposal landfill or as construction materials. A series of tests were performed to evaluate the basic properties, compaction, compressive strength, consolidation, permeability, and CBR of sewage ash. Specially, clay bricks were made as increasing replacement ratio of sewage ash (such as 5, 10, 15, 20, 25, 30%). And tests were fulfilled for its quality. Bentonite and lime were used as the additives to improve permeability properties of sewage sludge ash. As a result of tests, it was shown that the permeability coefficient decreases as increasing bentonite content and the percentage of bentonite was roughly needed 20% to keep the permeability coefficient below $1{\times}10^{-7}cm/sec$. The results of unconfined compression tests show that sewage ash meets the criteria of the unconfined compression strength for cover material. It was shown that the compressive strength decreases as increasing the replacement ratio of sewage sludge ash and the maximum replacement ratio of sewage sludge ash to satisfy the quality standards of the third degree bricks was about 15%.