• Korean Journal of Environment and Ecology
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• v.11 no.1
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• pp.126-132
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• 1997

Nanji-do is an island in Seoul, the area is 272ha, and in which gad was piled up waste discharged from Seoul metropolitan for 15 years(form March 1978 to March 1993). The volume of waste is 92, 000, 000m$^{2}$. The actual vegetation area of Nanji-do is 191ha, and the area of woody plant is 31ha. The rest area is covered by herbaceaus plant. In actual vegetation area of woody plant, Robinia pseudoacacia community and Salix pseudo-lasiogyne community are 83%. The soil pH is alkaline, though general soil pH is acid in Seoul. There is no relation with soil condition and actual vegetation. The result of this study, actual vegetation of Nanji-do don't help the establishment of vegetation restoration after soil stabilization construction. And so following a countermeasure is proposed. 1) Selection of adequate species by an experiment of planting pioneer species, native species, and dietary species 2) Establishment of an adequate planting plan and development of slope stabilization method by planting of native species 3) Establishment of a restoration plan of animal ecosystem by survey for animal ecosystem

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.4
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• pp.51-66
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• 2001

There occurred a moderate size earthquake of Magnitude 5 in Whagae-Myun, Hadong-GUn, Kyongsangnam-Do on July 4, 1936. It caused severe damage to the buildings and other structures in Sang-Gye-Sa, a Buddhist Temple. The top component of a five-story stone pagoda was tipped over and fell down to the ground during the earthquake. In order to have accurate and quantitative estimate of the peak acceleration level of that earthquake, a full-scale model was constructed through rigorous verification process. The complete model was mounted on a shaking table and subjected to the dynamic tests. Two kinds of tests were performed: exploratory test and fragility test. The exploratory test was done with low acceleration level. In the fragility test, the behavior of the model was carefully monitored while increasing the acceleration level. The construction details of the model are provided and test procedures are reported. Finally important test results are presented and their implications are discussed.

• Journal of the Korean Geotechnical Society
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• v.35 no.12
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• pp.35-44
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• 2019

In this study, the axial stiffness of reinforcing piles (K_vr) for the vertical extension remodeling structures was estimated through 3D finite element analysis. In the computation of the minimum required axial stiffness of reinforcing piles, proposed maximum axial stiffness of old and deteriorated existing piles (K_ve) based on theoretical and experimental approaches will be applied. Through this, the required increase rate of axial stiffness of reinforcing piles in order to support the increased structural loading was proposed for end-bearing and friction piles by different slenderness ratio (L/D). The numerical model was validated by comparing the computed results with actual field measurements. Based on the computed results, it was concluded that the end-bearing reinforcing pile needs 44% - 67% increase in axial stiffness to deal with the deterioration of existing piles and support the additional structural load due to vertical extension remodeling.

• Journal of the Korean Geotechnical Society
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• v.35 no.12
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• pp.25-33
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• 2019

In this study, the axial stiffness of existing piles (K_ve) of vertical extension remodeled building was quantified through theoretical and experimental approaches. Theoretically induced upper and lower boundary of the pile axial stiffness was estimated by using the formula proposed by Randolph and Wroth (1978), which can estimate the axial stiffness of rigid and flexible pile subjected under soil confinement. In addition, 38 cases of field measurement data on deteriorated piles with various diameters constructed in the period between 1995 - 1997 were taken in to account by overlapping the field data with the theoretical boundary of the axial stiffness. Through this the maximum axial stiffness of existing pile due to deterioration and long service time was presented for various slenderness ratio (L/D), which can be used in estimating the necessary axial stiffness of reinforcing piles(K_vr) for the vertical extension remodeling. The lower 95% value of the estimated axial stiffness of existing pile will be induced through statistical processing.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.379-384
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• 2014

In general, fractal analysis which is based on self-similarity as a basic theory has been mainly used to define the characteristics of complex mathematical figures, however, considering its basic theory, it can be also used to analyze the surface ununiformity of unknown materials. In this study, the soil samples were collected from the reclaimed (remodelled) agricultural fields which mean that the external soil is artificially piled up (mainly up to 1m) on the lands, Naju, Jellanam-do and Gumi, Gyeongsangbuk-do, and the conventional agricultural fields, Anseong, Gyeonggi-do and Hwasoon, Jellanam-do, and compared using fractal dimension analysis on the basis of the results of chemical properties. The score of fractal dimension ($D_0$) for organic matter was lower in Hwasoon (1.46) and Naju (1.58) than Anseong (1.86) and Gumi (1.96), and this trend showed similarly in soil pH. On the basis of the results of chemical properties, fine textured-soils (Hwasoon and Naju) and conventional agricultural fields were chemically uniform compared to coarse textured-soils (Anseong and Gumi) and the reclaimed. Therefore, it is required to develop technical methods for integrated soil management to the reclaimed lands.

• Journal of the Korea Fashion and Costume Design Association
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• v.17 no.1
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• pp.39-52
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• 2015

This study aims to analyze the characteristics of the male products for urinary incontinence by examining the types and characteristics of those registered in KIPO (Korean Industrial Property Office). Additionally, the types and characteristics, especially for the cloth products and the pads, of male panties for urinary incontinence on the market are analyzed. Men in their 60s with minor symptoms were selected as the subjects to evaluate the wearability. The results are as follows. 11 male products for urinary incontinence, registered in KIPO, are structurally different from those for women by having a separate pocket mainly for absorption. There are one disposable type and 7 cloth types, and the cloth panties can be classified as either united or separable type depending on the detachability of pads from the panties. The types of the panties vary according to the position, shape, and size of the attached pads on normal male panties (boxer, briefs, drawers). The fabrics for the urinary incontinence are usually piled in 3 to 5 layers by having the most absorptive layer on the top, the next with deodorizing characteristics, and the bottom with the waterproof fabric as basics with some additional layers of antibiotic or breathable fabrics. From the wearability test, it has been determined that the panties are not distinguishable in external appearance and the fitness is also not a problem since the size varies as the normal panties. It has been evaluated that the fitness of the panties is an important factor since the pad should be worn in any form; the pad sewed in the middle of the panties was evaluated to be more wearable than having a long pad. In case of separable panties, when the pattern and fabric is similar to the functional panties and the options such as the thickness of the pads or detachability are given to the users, it tends to be more satisfactory.

• The Journal of the Korean dental association
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• v.53 no.5
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• pp.348-359
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• 2015

Objective: The aim of this study was to determine the effect of multi-layer of a collagen membrane alone or loaded rhBMP-2 on the buccal plate for ridge preservation after tooth extraction. Material and methods: Following bilateral extraction of the maxillary 1st and 3rd premolars in five dogs, rhBMP-2 loaded collagen membrane was applied to the buccal plates at the 1st premolar and collagen membrane only was applied to the buccal plates at the 3rd premolar unilaterally. The collagen membranes applied in the experimental groups were piled into four layers. The corresponding sites of the contralateral side healed naturally. After 3months of healing, the animals were sacrificed. Radiographic and histologic analyses were performed. Results: There was no significant difference in the healing of extraction socket at both 1st and 3rd premolars. In microcomputed tomography, the widths of the residual ridge of the experimental groups were similar with the controls. Histologically, the experimental groups did not exhibit different pattern compared to the controls regardless of the addition of rhBMP-2. Conclusion: Layering of the collagen membrane with or without rhBMP-2 on the buccal plate failed to show the effectiveness in dimensional preservation of the extraction socket.

• Journal of the Korean Geographical Society
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• v.39 no.1
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• pp.56-69
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• 2004

We investigated the distribution and geomorphic development of alluvial fan in Gyeongju City including Cheonbuk area. According to a relative height to a river bed, alluvial fans of this area are divided into Higher surface, Middle surface, and Lower surface. As alluvial fans of Bulguk temple∼Ulsan bay area, the confluent fans in Cheonbuk and Gyeongju areas were formed by the Quaternary climatic change alternating glacial and interglacial stages, and the development of N-S and NW-SE fault lines. The Gyeongju alluvial fan, the largest in Korea, has been provided as the significant space for human activity since the prehistoric age. Bukcheon river formed the Gyeongju alluvial fan had not flowed over during the prehistoric and the ancient times. In contrast with general geomorphic characteristics, many springs in the Gyeongju alluvial fan are located in the middle part of the fan because ground water reaches to the surface. It is supposed that sedimental materials were not sufficiently piled up at lower reach of Bukcheon river due to the large deposits at upper and middle reach of the basin.

• Journal of the Korea Institute of Building Construction
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• v.2 no.2
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• pp.165-172
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• 2002

A reinforced concrete building neighboring in Pusan or Ulsan where is directly exposed to salt water contrasting with other in land areas contains much salt content percolated from the outside that the high salt content percolates and diffuses through the inside of reinforced concrete; therefore, an immovable tunic surrounding it begins to be destroyed and eroded with high speed. At the time, the cross-sectional area and volume expansion of re-bar reinforcing result in being cracks make a rapid progress gradually until they appear in the surface of the one, the phenomenon such as being a thin layer or falling off the part of it causes a lowering of its durability and might collapse the concrete construction. So far, we've investigated into salt content of reinforced concrete constructions neighboring in a seaside district and damage by carbonation, and we came to a conclusion as follows: $\circled1$ Under the oceanic circumstance a concrete construction is influenced by sea water directly that contains much amount of salt content contrasting with other constructions on inland areas. $\circled2$ Because of chloride penetration the carbonation of reinforced concrete made a rapid progress until more than the covering thickness of re-bar. $\circled3$ An old reinforced concrete building which has been piled up salt injury and proceeding the carbonation of its cross-sectional area. $\circled4$ According to rapidly cracking from the inside to surface of reiforced concrete, the phenomenon of being a thin layer or falling off the part of reinforced concrete results in a lowering of durability and shortening the life-time of concrete construction itself.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.6
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• pp.117-125
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• 1998

The paper attempts to estimate the incubation time of a cavity in the interface between a power law creep particle and an elastic matrix subjected to a uniaxial stress. Since the power law creep particle is time dependent, the stresses in the interface relax. The volume free energy associated with Helmholtz free energy includes strain energies caused by applied stress and dislocations piled up in interface(DPI). The energy due to DPI is found by modifying the result of Dundurs and Mura[4]. The volume free energies caused by both applied stress and DPI are a function of the cavity size(r) and elapsed time(t) and arise from stress relaxation in the interface. Critical radius $r^*$ and incubation time $t^*$ to maximise Helmholtz free energy is found in present analysis. Also, kinetics of cavity formation are investigated using the results obtained by Riede [7]. The incubation time is defined in the analysis as the time required to satisfy both the thermodynamic and kinetic conditions. Through the analysis it is found that 1) strain energy caused by the applied stress does not contribute significantly to the thermodynamic and kinetic conditions of a cavity formation, 2) in order to satisfy both thermodynamic and kinetic conditions, critical radius $r^*$ decreases or holds constant with increase of the time until the kinetic condition(eq. 2.3) is satisfied. there for the cavity may not grow right after it is formed, as postulated by Harris [15], and Ishida and Mclean [16], 3) the effects of strain rate exponent (m), material constant $\sigma$0, volume fraction of the particle to matrix(f)and particle size on the incubation time are estimated using material constants of the copper as matrix.