• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.4
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• pp.1227-1240
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• 2014

Abandoned mines often cause environmental problems, such as alteration of landscape, metal contamination, and landslides due to a heavy rainfall. Geotechnical and rheological tests were performed on waste materials corrected from Imgi waste rock dump, located in Busan Metropolitan City. Debris flow mobility was examined with the help of 1-D BING model which was often simulated in both subaerial and subaqueous environments. To determine flow curve, we used a vane-penetrated rheometer. The shear stress (${\tau}$)-shear rate (${\dot{\gamma}}$) and viscosity(${\eta}$)-shear rate (${\dot{\gamma}}$) relationships were plotted using a shear stress control mode. Well-known rheological models, such as Bingham, bilinear, Herschel-Bulkley, Power-law, and Papanastasiou concepts, were compared to the rheological data. From the test results, we found that the tested waste materials exhibited a typical shear shinning behavior in ${\tau}$-${\dot{\gamma}}$ and and ${\eta}$-${\dot{\gamma}}$ plots, but the Bingham behavior is often observed when the water contents increased. The test results show that experimental data are in good agreement with rheological models in the post-failure stage during shearing. Based on the rheological properties (i.e., Bingham yield stress and viscosity as a function of the volumetric concentration of sediment) of waste materials, initial flowing shape (5 m, 10 m, and 15 m) and yield stress (100 Pa, 200 Pa, 300 Pa, and 500 Pa) were input to simulate the debris flow motion. As a result, the runout distance and front velocity of debris flow are in inverse propositional to yield stress. In particular, when the yield stress is less than 500 Pa, most of failed masses can flow into the stream, resulting in a water contamination.

• Journal of Oral Medicine and Pain
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• v.20 no.2
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• pp.429-447
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• 1995

This study was designed to determine the most effective concentration of fluoride and levels of laser irradiation for the remineralization of decayed teeth. After irradiation with a pulsed Nd:YAG laser and the topical application of fluoride, phosphate and fluoride concentration in enamel were measured. And then the changes on surface enamel using an scanning electron microscope were observed. Samples by extraction healthy, permanent, mandibular bovine teeth with no caries were obtained. Among them 371 healthy samples were selected and artificial carious lesions were made. 20 samples were assigned to each experimental group. After irradiation with a pulsed Nd:YAG laser with total energy densities of 10J/$\textrm{cm}^2$, 20J/$\textrm{cm}^2$ for each group. On the teeth, 2% NaF, 1.9% NH4F, 1.6% TiF4 Elmex gel(amine fluoride) and 1.23% APF gel were applied. After pH circulatory procedures, concentrations of fluoride with and Ionalyzer (Orion Research, Model 901, USA) and phosphates with an Uv/V is spectrophotometer (Uvikon 860, Kontrom Co, Switzerland) were measured. By etching the teeth in layers and measuring fluoride concentrations, a profile of fluoride penetration according to depth could be developed. And also the changes on the surface of the enamel using an electron scanning microscope were observed. The comparative analysis yielded the following results : 1. Phosphate concentration was low in all groups compared with the control group except for teeth treated Elmex gel, irradiated with 10J/$\textrm{cm}^2$ and 30J/$\textrm{cm}^2$ energy densities. Teeth treated with APF gel and 30J/$\textrm{cm}^2$ irradiation gad the lowest phosphate concentration. 2. Among all groups, fluoride concentrations in tooth enamel were highest in APF gel and NaF groups irradiated at 30J/$\textrm{cm}^2$. The APF gel group had the highest fluoride concentrations across all energy densities. 3. In the APF gel group, and the NaF group, the greater the energy density of the laser, the higher the fluoride concentrations in the enamel. 4. In all groups, the concentration of fluoride in the enamel by depth tended to decrease with depth. 5. Under the scanning electron microscope, under the condition of irradiation with 20J/$\textrm{cm}^2$, enamel crack was detected for the first time. In the NH4F group, spherical deposits were found on the surface of the enamel, and in the TiF4 group the surface of enamel was covered with an irregular, thin membranous mass in places. In the APF gel and NaF groups irradiated with 10J/$\textrm{cm}^2$, spherical and irregular particles covered the teeth. When these groups were irradiated at 20J/cm2, they were covered with amorphous crystals. These results suggest that one could obtain more effective anticariogenic effects without damage to teeth when less than 20J/$\textrm{cm}^2$ energy densities and APF gel are used.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.2
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• pp.227-238
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• 2006

Line density index(LDI) was developed to quantify a densely isothermal line rate as standard index in the ocean environment. Theoretical background on the LDI development process restricting index range 0 to 100 was described. And validation test was done for the LDI application condition that total line length is not greater than 1/10 of unit area. NOAA SST(Sea Surface Temperature) data were used for the experimental application of LDI in the South Sea of Korea. Using GIS, $0.1^{\circ}C$ isothermal lines were linearized as vector data form SST raster data, and unit area were built as polygon data. For the LDI calculation, spatial overlapping(line in polygon) was implemented. To analyze the effect of unit area size for the LDI distribution, two cases of unit area size were designed and descriptive statistics was calculated including performing normality test. The results showed no change of LDI's essential characteristics such as mean and normality except for the range of value, variance and standard deviation. Accordingly, it was found that complex structure of thermal front and even smaller scale of front width than unit area size could influence on the LDI distribution. Also, correlation analysis performed between LDI and difference of temperature(${\Delta}T^{\circ}C$), and horizontal thermal gradient(${\Delta}T^{\circ}C/km$) on the front was obtained from linear regression model. This obtained value was compared with the results from previous researches. Newly developed LDI can be used to compare the thermal front regions changing spatio-temporally in the ocean environment using absolute index value. It is considered to be significant to analyze the relationship between thermal front and marine environment or front and marine organisms in a quantitative approach described in this study.

• Journal of the Korean Geographical Society
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• v.41 no.5 s.116
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• pp.582-599
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• 2006

Due to the growing popularity of mobile information technology, more people, especially in the general public, have access to computerized geospatial information systems for wayfinding tasks or urban navigation. One of the problems with the current services is that, whether the users are exploring or navigating, whether they are travelers who are totally new to a region or long-term residents who have a fair amount of regional knowledge, the same method is applied and the direction are given in the same way. However, spatial knowledge for a given urban region expands in proportion to residency. Urban navigation is highly dependent on cognitive mental images, which is developed through spatial experience and social communication. Thus, the wayfinding service for a regional community can be highly supported, using well-known regional places. This research is to develop the framework for urban navigation within a regional community. The concept of communal ontology is proposed to aid in urban regional navigation. The experimental work was implemented with case study to collect regional landmarks, develop the ontological model and represent it with formal structure. The final product of this study will provide the geographical information of a region to the other agent and be the fundamental information structure for cognitive urban regional navigation.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.838-846
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• 2016

Most of combustion processess used in industries require recovering or removing flue gas components. Recently a new MBA (moving bed adsorption) process for recovering $CO_2$ using zeolite 13X was developed. In this study, adsorption experiments for carbon dioxide, nitrogen, sulfur dioxide, and water vapor on zeolite 13X were carried out. Adsorption equilibrium and adsorption rate into solid particle were investigated. Langmuir, Toth, and Freundlich isotherm parameters were calculated from the experiment data at various temperatures. Experimental results were consistent with the theoretically predicted values. Also $CO_2$ adsorption amount was measured under the conditions with impurities such as $SO_2$ and $H_2O$. Binary adsorption data were well fitted to the extended Langmuir isotherm using parameters obtained from pure component experiment. However, $H_2O$ impurity less than, roughly, ${\sim}10^{-5}H_2O\;mol/g$ zeolite 13X enhanced slightly $CO_2$ adsorption. Spherical particle diffusion model well described experimentally measured adsorption rate. Diffusion coefficients and activation energies of $CO_2$, $SO_2$, $N_2$, $H_2O$ were obtained. Diffusion coefficients of $CO_2$ and $SO_2$ decreased with small amount of preadsorbed impurity. Parameter values from this study will be helpful to design of real commercial adsorption process.

• Journal of Acupuncture Research
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• v.18 no.1
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• pp.113-128
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• 2001

Objective : To investigate the effect of BUM aqua-acupuncture in treating the RA, the immunosis to logical analysis of LPS induced arthritis in mice to study this. For 14th day after the injection of LPS & BUM injection, the distribution of fibroblast, collagen, CD54(ICAM-1), CD106(VCAM-1), IL-$1{\beta}$, IL-2 receptor, CDl lb(macrophage) were examined on synovial capsule of mice knee joint. For 14th day after the injection of LPS & BUM injection, the distribucion of CD4(TH cell), CD8(TC cell), CD40(B cell) were examined on common iliac lymph node in mice. Methods : The experimental model of arthritis was induced by injection of 300${\mu}g$/kg LPS in BALB/c mice weighing 30g. The 100${\mu}l$ BUM aqua-acupuncture which compounded calculus bovis, fel ursi and moschus was injected into GB34 of mice every other day for 12 days. For 3rd, 7th, 14th day after the injection of LPS, the neutrophil, lymphocyte and monocytc counts in WBC were measured using hemacytometer. Results : The obstain results are summarized as follows ; 1. In sample group, the neutrophils counts were increased and the lympnocytes counts were decreased compared with control group. 2. The distribution of fibrosis & fibroblast on synovial membrane were decreased compared with control group. 3. The distribution of collagen fiber on synovial membrane were decreased compared' with control group. 4. The distribution of CD54(ICAM-1) & CD106(VCAM-1) on synovial membrane were decreased compared with control group. 5. The distribution of IL-$1{\beta}$ & IL-2 receptor on synovial membrane were decreased compared with control group. 6. The distribution of CDb(macrophage) on synovial membrane were decreased compared with control group. 7. The distribution of CD4(TH cell), CD8(TC cell) and CD40(B cell) in common iliac lymph nodes were decreased compared with control group. Conclusions : BUM aqua-acupuncture stimulation decreased inflammatory responses LPS induced arthritis in mice.

• Journal of the Korea Concrete Institute
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• v.19 no.3
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• pp.283-292
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• 2007

A research projects is currently being conducted to develop a nonlinear finite element analysis methods for predicting the structural behavior of reinforced concrete frame structures, exposed to fire. As part of this, reinforced concrete frames subjected to fire loads were analyzed using the nonlinear finite-element program DIANA. Two numerical steps are incorporated in this program. The first step carries out the nonlinear transient heat flow analysis associated with fire and the second step predicts the structural behavior of reinforced concrete frames subjected to the thermal histories predicted by first step. The complex features of structural behavior in fire conditions, such as thermal expansion, plasticity, cracking or crushing, and material properties changing with temperature are considered. A concrete material model based on nonlinear fracture mechanics to take cracking into account and plasticity models for concrete in compression and reinforcement steel were used. The material and analytical models developed in this paper are verified against the experimental data on simple reinforced concrete beams. The changes in thermal parameters are discussed from the point of view of changes of structure and chemical composition due to the high temperature exposure. Although, this study considers codes standard fire for reinforced concrete frame, any other time-temperature relationship can be easily incorporated.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.13 no.2
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• pp.59-73
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• 2002

Libraries, not only research libraries but also public libraries, have been fundamentally affected by the immense spread of the Internet and the World Wide Web. Many public libraries have their Web pages, through which they are providing their new and conventional services. There are also web sites which provide library-like services. This paper shows an experimental project named Internet Public Library Asia, which provides information in multiple languages of information resources published in Chinese, Japanese and Korean languages. This paper firstly overviews how traditional public libraries have been affected by the Internet. Then, it describes a few aspects from the viewpoint of crucial library function on the Internet and also from the viewpoint of Asian resources and users. This paper secondly proposes a model to serve information about valuable resources published in multiple Asian languages, and then shows the metadata schema and a few software tools developed for IPL-Asia The name of IPL is borrowed from Internet Public Library based at University of Michigan, since it is, in part, a collaborative activity with the IPL in Michigan. The metadata schema is defined based both on Dublin Core and IEEE LOM and adapted for parallel description in the four languages, i. e. , Chinese, Japanese, Korean and English. The software tools provide functions to support collaboration among people engaged in development of metadata database and metadata editing. These tools have been developed based on the XML technologies.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.4
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• pp.125-133
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• 1989

For convergent photos, which are now widely adopted for terrestrial facility survey, a number of experimental studies and theoretical studies on the developments of accuracy predictional model according to the convergent angle change have been accomplished. And such studies are basically depend on the symmetrical geometric configuration at the normal direction to the center of the object. However, in may cases of facility survey such as building facades, bridges, dam surfaces, relatively flat topography, etc., the object features are almost like planar, and frequently the surroundings do not allow the photo station at normal direction, and the sufficient convergent angle can be hardly achieved. Considering those points, in this study, the accuracy analysis on three dimensional coordinates according to the variations of photo direction and of convergent angle to the planar object were attempted, and the optimum geometric configurations at the normal, side-looking, and the most side-looking direction were investigated. The result through this study show that from normal direction to the side-looking direction angle ${\tau}=30^{\circ}$, the larger the convergent angle, the higher the accuracy, and in case that right photo is at the most side-looking direction, the better accuracy can be achieved according to the convergent angle increase up to $60^{\circ}$.

• The Journal of Internal Korean Medicine
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• v.33 no.2
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• pp.222-230
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• 2012

Background : Interstitial cystitis is a disorder of the bladder characterized by urgency and frequency of urination, and pelvic pain. The cause of interstitial cystitis is not clear. Modern medical treatments include behavioral therapy, medication, intravesical infusion therapy, and surgical treatment, but the goal of treatment is based on symptom relief rather than a cure. According to a recent report, in an animal model, oriental medicine treatment, Yukmijihwang-tang improved the symptoms of interstitial cystitis. However, clinical studies and experimental research are lacking. Objectives : In this study, We investigated Chuknyojetong-tang, acupuncture, moxibustion and bee venom effect on interstitial cystitis. Methods : We targeted 25 patients diagnosed with interstitial cystitis at the university hospital and treated them for more than one month. We used acupuncture, Chuknyojetong-tang, and bee venom. The effects were evaluated using ICSI and ICPI at the begin of treatment and at the end of treatment. Results : All of the 25 patients were female, average age was $53.3{\pm}13.5$ years, and the average month of disease-duration was $69.0{\pm}59.8$. The duration of treatment was $8.0{\pm}5.4$ months, and 60% of patients were improved. After treatment, we used correlation coefficient method, multiple regression analysis. ICSI difference increased as treatment period increased. ICPI difference increased as age decreased. Total difference also increased as treatment period increased. These results imply that treatment effect was improved. Conclusions : These findings suggest that oriental medicine therapy using Chuknyojetong-tang, acupuncture, moxibustion, and bee venom would be very effective on interstitial cystitis.