• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.5
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• pp.285-295
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• 2020

In the case of small observation towers located at sea, it is necessary to confirm the change in dynamic characteristics due to the influence of environmental loads. In this study, the dynamic characteristics were analyzed and the numerical analysis model was designed through field dynamic response measurement on the Mangyeong Offshore Observation Tower (Mangyeong Tower) located near the Saemangeum Embankment. As a result of the measurement, the natural frequency was found to increase slowly as the tide level is lowered. In addition, it was confirmed that the same mode has two frequencies, which was judged to be a phenomenon in which the natural frequency was partially increased when the pile and the ground contacted by scouring. For numerical analysis, the upper mass, artificial fixity point, scour depth and fluid influences are reflected in the structural characteristics of the Mangyeong Tower. In addition, the model updating from the estimated natural frequency and pattern search algorithm was performed. From the model updating, it is expected that it can be applied to future studies on stability of Mangyeong Tower.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.1
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• pp.73-78
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• 2005

It was aimed to promote Cyrtomium falcatum as a material for interior landscape by validating it indoor adaptability in the indoor environment, especially irrigation times, soil treatment and drainage level. Irrigation times were 2 times per week and 7 times per week. Soil treatment and drainage level were carried out drainage-peatmoss : vermiculite : perlite=1 : 1 : 1(D-PVP), peatmoss : vermiculite : perlite=1 : 1 : 1(PVP), drainage-saprolite : leaf mold=1 : 1(D-SL) and saprolite : leaf mold=1 : 1(SL). 1. Top of growth was better with irrigation 7 times per week than irrigation 2 times per week but indoor adaptability was decreased and shown yellowish green. 2. In case of soil treatment, growth was better with saprolite : leaf mold=1 : 1 but indoor growth adaptability was decreased than peatmoss : vermiculite : perlite=1 : 1 : 1. 3. Plant height and blade length were increased under non-drainage treatment but indoor adaptability, number of new fronds and number of sporophyll were decreased under drainage treatment, regardless of irrigation times and soil treatment. 4. Photosynthetic rate(Pn) was the highest in the drainage-peatmoss : vermiculite : perlite=1 : 1 : 1 treatment of irrigation 2 times per week and was the lowest in the saprolite : leaf mold=1 : 1 treatment of irrigation 7 times per week.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.2
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• pp.163-170
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• 2004

A new oil crop chufa(Cyperus esculentus var. sativus) was studied to evaluate the yield potential of tuber and productivity of leaf as a new forage crop resources. Response to nitrogen fertilizer was not clear, showing low yield over 10kg/l0a of nitrogen application. Tuber yield was higher at 50cm $\times$ 15cm and 50cm$\times$20cm of planting population of tuber. Planting at early May showed high tuber yield, and sprouting tuber planting could not increased the tuber yield. The plant height of Chufa is 126cm, and the number of tiller per $\m^2$ are 671. It is moderate to lodging, but susceptable according to the amount of field products. Fresh forage and dry matter yield of above ground of chufa were 2,135kg/10a, and 590kg/l0a, respectively. The contents of crude protein, ether extract, fiber, ash, and acid detergent fiber are 24.8%, 8.1%, 38%, 64.4%, 52.8%, and 55.9%, respectively. It was considered that the nutritive value of chufa leaf in maturing stage was so good as rice straw.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.777-782
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• 2010

This research tested five modified Hoagland solutions for proper fertility management of nitrogen in 'Seolhyang' strawberry cultivations. The changes of nutrient solutions were in total nitrogen concentrations ($meq{\cdot}L^{-1}$) such as 0 (${NO^-}_3$), 2.5 (${NO_3}^-$), 5 (${NO_3}^-$), 10 ($7.5{NO_3}^-$ + $2.5{NH_4}^+$) and 15 ($10{NO_3}^-$ + $5{NH_4}^+$). The fresh weight and $NO_3$-N concentrations in petiole sap responded to the elevated nitrogen concentrations in fertilizer solution in quadratic (y=7.10+2.668x-$0.115x^2$, $R^2=0.7983^{***}$) and linear (y=26.14+5.245x, $R^2=0.6083^{***}$), respectively. The dry weight and N content of the above ground plant tissue responded to the elevated nitrogen in quadratic (y=2.140+0.492x-$0.022x^2$, $R^2=0.6110^{***}$) and linear (y=0.569+0.033x, $R^2=0.6952^{***}$), respectively. In our experiment the solution with $5meq{\cdot}L^{-1}$ of ${NO_3}^-$ showed positive results in both dry and fresh weight productions. However, a future research about modification of this solution and growth and nutrient uptake response is necessary to achieve better growth of 'Seolhyang' strawberry.

• The Journal of Advanced Prosthodontics
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• v.6 no.1
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• pp.14-21
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• 2014

PURPOSE. The purpose of this study was to evaluate bone response to anodized titanium implants coated with the extract of black cohosh, Asarum Sieboldii, and pharbitis semen. MATERIALS AND METHODS. Forty anodized titanium implants were prepared as follows: group 1 was for control; group 2 were implants soaked in a solution containing triterpenoids extracted from black cohosh for 24 hours; group 3 were implants soaked in a solution containing extracts of black cohosh and Asarum Sieboldii for 24 hours; group 4 were implants soaked in a solution containing extracts of pharbitis semen for 24 hours. The implants from these groups were randomly and surgically implanted into the tibiae of ten rabbits. After 1, 2, and 4 weeks of healing, the nondecalcified ground sections were subjected to histological observation, and the percentage of bone-to-implant contact (BIC%) was calculated. RESULTS. All groups exhibited good bone healing with the bone tissue in direct contact with the surface of the implant. Group 2 ($52.44{\pm}10.98$, $25.54{\pm}5.56$) showed a significantly greater BIC% compared to that of group 3 ($45.34{\pm}5.00$, $22.24{\pm}2.20$) with respect to the four consecutive threads and total length, respectively. The BIC% of group 1 ($25.22{\pm}6.00$) was significantly greater than that of group 3 ($22.24{\pm}2.20$) only for total length. CONCLUSION. This study did not show any remarkable effects of the extract of black coshosh and the other natural products on osseointegration of anodized titanium implants as coating agents. Further studies about the application method of the natural products on to the surface of implants are required.

• 한국지구물리탐사학회:학술대회논문집
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• 2000.09a
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• pp.112-131
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• 2000

In spite of its many strong points, pole-pole electrode configuration is not often used for ground electrical resistivity survey except for bore hole survey as normal logging and for archaeological investigation. Above all, poor spatial resolution of pole-pole survey may be responsible for this. But recent experiences so far gained by the present authers lead them to think that pole-pole survey can be at least a viable means of reconnaissance survey in near-surface conductive environment and an effective interpretational scheme may augment its resolution. As well known, a response of any other electrode configuration is a linear combination of pole-pole responses. Based on this principle of linear superposition and the principle of reciprocity, the other 'responses' can be derived with simple additions and subtractions of pole-pole responses. Though such responses are not always correct due to the adverse effects of noises, combined with the potential decay curves, they can be helpful to interprete better pole-pole survey data especially in connection of the resolution. This can be comparable to the use of the first or second derivatives of gravity and magnetic intensity surveys.

• Journal of Korean Elementary Science Education
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• v.25 no.4
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• pp.363-373
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• 2006

The purposes of this study were to analyze the within-group verbal interactions in Thinking Science activities and compare the characteristics of verbal interactions shown by the pupils as well as the differences in help by e teacher in Korea with those in the UK. For the purposes of this study, 16 pupils from comparable groups by cognitive level were selected from both countries. Verbal interactions and teacher help during group discussions were audio/ video taped and the types of students' interactions were classified into interactions related to problem solving, management of classroom loaming and others. The results of this study showed that the verbal interactions in Korean groups were more activated than those in the UK groups. However, the percentages of high level interactions such as metacognitive questions, elaborative suggestions and logical argumentations were higher in the UK groups than those in the Korean groups. Observation of the within-group activities revealed that the pupils of both countries shared some common ground in the following ways; neither recognized the need to formulate the hypothesis in the process of inquiry and that the procedures of discussion were dominated by the pupils of higher cognitive level as the discussion proceeded. It was also observed that the pupils in the UK were considerate in response to the questions posed by both their peers or the teacher, while the pupils in Korea were influenced by their prior knowledge in the subject. Analysis of the teacher help during the inquiry activities showed that the tendency fur the teacher to emphasize the process rather than the product in the procedures of discussion and the extent he/she allowed the pupils to think and consider were closely related to the characteristics of the teacher himself/herself and was found to be a point of commonality in both countries. However, the teachers in the UK revealed the tendency of trying to propose the task to the pupils in concrete and systematic ways and guide the discussion based on the thinking of the pupils, while those in Korea tried to use strategies designed to draw out active verbal interactions among the pupils.

• Journal of Environmental Science International
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• v.19 no.7
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• pp.871-877
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• 2010

The objectives of this study were to compare growth of Pllioblastus pygmaed and soil characteristics as affected by difference of soil thickness and mixture ratio in shallow-extensive green roof module system, and to identify the level of soil thickness and mixture as suitable growing condition to achieve the desired plants in green roof. Different soil thickness levels were achieved under 15cm and 25cm of shallow-extensive green roof module system that was made by woody materials for $500{\times}500{\times}300mm$. Soil mixture ratio were three types for perlit: peatmoss: leafmold=6:2:2(v/v/v, $P_6P_2L_2$), perlit: peatmoss: leafmold=5:3:2(v/v/v, $P_5P_3L_2$) and perlit: peatmoss: leafmold=4:4:2(v/v/v, $P_4P_4L_2$). On June 2006, Pllioblastus pygmaed were planted directly in a green roof module system in rows. All treatment were arranged in a randomized complete block design with three replication. The results are summarized below. In term of soil characteristics, Soil acidity and electric conductivity was measured in pH 6.0~6.6 and 0.12dS/m~0.19dS/m, respectively. Organic matter and exchangeable cations desorption fell in the order: $P_4P_4L_2$ > $P_5P_3L_2$ > $P_6P_2L_2$. $P_6P_2L_2$ had higher levels of the total solid phase and liquid phase, and $P_4P_4L_2$ had gas phase for three phases of soil in the 15cm and 25cm soil thickness. Although Pllioblastus pygmaed was possibled soil thickness 15cm, there was a trend towards increased soil thickness with increased leaf length, number of leaves and chlorophyll contents in 25cm. The growth response of Pllioblastus pygmaed had fine and sustain condition in order to $P_6P_2L_2$ = $P_5P_3L_2$ > $P_4P_4L_2$. However, The results of this study suggested that plants grown under $P_4P_4L_2$ appear a higher density ground covering than plants grown under $P_6P_2L_2$. Collectively, our data emphasize that soil thickness for growth of Pllioblastus pygmaed were greater than soil mixture ratio in shallow-extensive green roof module system.

• Tuberculosis and Respiratory Diseases
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• v.51 no.6
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• pp.597-602
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• 2001

A 47-years-old woman presented with a 2-month history of a dry mouth and dry cough. The patient had been taking medication for Sj$\ddot{o}$gren's syndrome for approximately 7 years. The chest radiography showed multiple cystic lesions and a hazy density in both lower lung fields. The HRCT showed a diffuse ground glass like appearance and multiple variable sized cystic lesions in both lung fields. After medication, the symptoms were aggravated. Bronchoscopy was preformed with a transbronchial lung biopsy. The biopsies showed an infiltration of lymphocytes, neutrophils, monocytes and histiocytes through the interstitial space of the alveola and a widening of the alveolar septa. However, the histological findings of the cysts were not obtained. Sj$\ddot{o}$gren's syndrome is a slowly progressive inflammatory autoimmune disease, which is characterized by lymphocyte mediated destruction of the exocrine glands, with pulmonary involvement in approximately 19-65%, High-resolution CT is a sensitive technique for assessing the pulmonary involvement in patients with Sj$\ddot{o}$gren's syndrome. Although a lung biopsy is not always necessary for establishing a diagnosis of an interstitial lung disease in Sj$\ddot{o}$gren's syndrome. A lung biopsy may reveal a wide spectrum of changes ranging from a mild inflammatory response to end stage fibrosis with honeycombing. Because of the predominantly peribronchiolar inflammatory infiltration and inspissated secretions the cysts were suspected to have been formed by the ball-valve phenomen. However, no definite evidence was obtained.

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.5
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• pp.61-69
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• 2007

The main purpose of this study is to provide a basic information for the seismic capacity evaluation and the seismic design of low-rise reinforced concrete (RC) shear wall buildings, which are comprised of a pilotis in the first story. In this study, relationships between strengths and ductilities of each story of RC buildings with pilotis are investigated based on the nonlinear seismic response analysis. The characteristics of low-rise RC buildings with pilotis are assumed as the double degree of freedom structural systems. In order to simulate these systems, the pilotis is idealized as a degrading trilinear hysteretic model that fails in flexure and the upper story of shear wall system is idealized as a origin-oriented hysteretic model that fails in shear, respectively. Stiffness properties of both models are varied in terms of story shear coefficients and structures are subjected to various ground motion components. By analyzing these systems, interaction curves of required strengths for various levels of ductility factors are finally derived for practical purposes. The result indicates that the required strength levels derived can be used as a basic information for seismic evaluation and design criteria of low-rise reinforced concrete shear wall buildings having pilotis structure.