• Journal of the Mineralogical Society of Korea
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• v.24 no.3
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• pp.235-244
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• 2011

A batch experiment of pyrite oxidation was performed and the surfaces of the reacted pyrite were regularly observed with the scanning electron microscope (SEM) together with the chemical compositions of the solution to help understand the oxidation mechanisms of pyrite by Acidithiobacillus ferrooxidans (Af). The dissolved Fe concentrations clearly indicated that Af experiences the lag and then exponential growth phase. An Af cell was observed to be attached to the surface of pyrite during the lag, implying that a direct leaching by the microbe really happens for the period. It is not certain, however, whether the main mechanism of pyrite oxidation during that time was the direct leaching or not, because there were just a few cells confirmed to be attached and most of the dissolved Fe was Fe(III). The dissolved Fe concentration stayed almost constant from the mid-lag phase to just before the onset of the exponential phase, suggesting that AI needs an adaptation time to switch its oxidation mechanism from one to the other whichever it is during that stage of growth. The moment of Af's cell division was observed by SEM on the surface of pyrite during the lag phase. The corrosion outline around the dividing cell was quite similar to the shape of the cell itself, which implies that the rate of the microbial oxidation is very uneven and the rate when the cell metabolizes should be much faster than that calculated from the concentration variation of the dissolved Fe. The number of etch holes by Af is much higher on the inoculated surfaces, indicating the average rate of pyrite oxidation is also much faster than that of abiotic oxidation. The microbial etch holes on pyrite surface are small and deep, which may influence the transition of the growth phases of Af from lag to exponential.

• Progress in Medical Physics
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• v.13 no.4
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• pp.209-217
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• 2002

There have been many studies on the application of the reciprocal advantages of multimodality image to define accurate target volume in the Process of radiation treatment planning. For the proper use of the multimodality images, the registration works between different modality images should be performed in advance. In this study, we selected chamfer matching method and mutual information method as most popular methods in recent image registration studies considering the registration accuracy and clinical practicality. And the two registration methods were analyzed to deduce the optimal registration method according to the characteristics of images. Lung phantom of which multimodality images could be acquired was fabricated and CT, MRI and SPECT images of the phantom were used in this study. We developed the registration program which can perform the two registration methods properly and analyzed the registration results which were produced by the developed program in many different images' conditions. Although the overall accuracy of the registration in both chamfer matching method and mutual information method was acceptable, the registration errors in SPECT images which had lower resolution and in degraded images of which data were removed in some part were increased when chamfer matching method was applied. Especially in the case of degraded reference image, chamfer matching methods produce relatively large errors compared with mutual information method. Mutual information method can be estimated as more robust registration method than chamfer matching method in this study because it did not need the prerequisite works, the extraction of accurate contour points, and it produced more accurate registration results consistently regardless of the images' characteristics. The analysis of the registration methods in this study can be expected to provide useful information to the utilization of multimodality images in delineating target volume for radiation treatment planning and in many other clinical applications.

• The Journal of Korean Obstetrics and Gynecology
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• v.31 no.4
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• pp.16-38
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• 2018

Objectives: The objective of this in vivo study is to observe the anti-osteoporotic activities of Gojineumja aqueous extracts (GJEJ) on the ovariectomized (OVX) mice as compared to those of risedronate sodium (RES). Methods: Thirty five days after bilateral OVX, GJEJ was orally administered, for 35 days once a day and then the changes on the body weight and gain during experimental periods, femur weights, bone mineral density (BMD), bone strength (failure load), mineral contents - calcium (Ca) and inorganic phosphorus (IP), histological profiles and histomorphometrical analyses at sacrifice were conducted with serum biochemistry - osteocalcin contents and bone specific alkaline phosphatase (BALP) activities. And the results of GJEJ were compared with RES orally administered OVX mice. Results: As a result of OVX, noticeable increase of body weight and gains and serum osteocalcin levels, decrease of serum BALP activities, femur weights, femur Ca and IP contents, BMD and strength were observed as compared to those of sham control mice, respectively. Also, the decrease of all histomorphometrical indices indicating the bone mass and structure, and the increase of indices about resorption were also detected in the femur of OVX control. However, these estrogen-deficient osteoporotic signs were significantly and dose-dependently inhibited by 35 days of continuous oral treatment of GJEJ, at dose levels of 500, 250 and 125 mg/kg, respectively. Especially, GJEJ 500 mg/kg showed favorable inhibitory activities against estrogen-deficient osteoporosis symptoms induced by OVX as comparable to those of RES 2.5 mg/kg. Conclusions: The results in this study suggest that oral administrations of GJEJ have clear dose-dependent favorable anti-osteoporotic activities in OVX mice.

• Radiation Oncology Journal
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• v.24 no.1
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• pp.67-76
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• 2006

Purpose: Oral mucositis is a common toxicity of radiation or chemotherapy, which is used a treatment for head and neck cancer. We investigated effects of recombinant human epidermal growth factor (rhEGF) on radiation-induced oral mucositis in rat model. Materials and Methods: Spraque-Dawley rats (7 per group) exposed to a single dose of 25 Gy (day 0) on their head, except for one group, were randomly divided into un-treated, vehicle-treated, and two rhEGF-treated groups. Rats were topically applied with rhEGF (15 or $30{\mu}g/oral$ cavity/day) or vehicle to their oral mucosa. Survival rate of rats, weight changes, and food intakes were examined from day 0 to 18 after radiation. Histology study was performed from oral mucosa of rats at day 7 and 18 after radiation. Results: rhEGF-treated groups (15 or $30{\mu}g/oral$) showed all survival rate 33%, whereas un-treated and vehicle-treated groups showed all survival rate 0% at the end of experiment. rhEGF-treated groups statistically had less weight loss compared to vehicle-treated group from day 2 to 7 after radiation. Food intake of rats with rhEGF treatment turned to increase at day 14 after radiation. At 7 day after radiation, un-treated and vehicle-treated groups showed severe pseudomembraneous or ulcerative oral mucositis. On the other hand, rhEGF-treated groups had no more than cellular swelling and degeneration of epidermal cells in oral mucosa of rats. Conclusion: These results suggest that rhEGF has significantly positive effects on radiation-induced oral mucositis in rats. rhEGF display a therapeutic potential on a clinical level.

• The Korean Journal of Nuclear Medicine
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• v.39 no.6
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• pp.438-444
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• 2005

Purpose: Anhedonia has been proposed to be the result of a basic neurophysiologic dysfunction and a vulnerability marker that precede and contribute to the liability of developing schizophrenia. We hypothesized that anhedonia, as a construct reflecting the decreased capacity to experience pleasure, should be associated with decreased positive hedonic affect trait. This study examined the relationship between anhedonia and positive hedonic affect trait and searched for the brain legions which correlate with anhedonia in normal subjects. Materials and Methods: Using $^{18}F$-FDG PET scan, we investigated the brain activity of twenty one subjects during resting state. Questionnaires were administrated after the scan in order to assess the self-rated individual differences in physical/social anhedonia and positive/negative affect traits. Results: Negative correlation between physical anhedonia score and positive affect trait score was significant (Pearson coefficient =-0.440, p<0.05). The subjects physical and social anhedonia scores showed positive correlation with metabolic rates in the cerebellum and negative correlation with metabolic rates in the inferior temporal gyrus and middie frontal gyrus. In addition, the positive affect trait score positively correlated with various areas, most prominent with the inferior temporal gyrus. Conclusion: These results suggest that neural substrates, such as the inferior temporal gyrus and prefrontal-cerebellar circuit, which dysfunction has been proposed to be involved with the cognitive deficits of schizophrenia, may also play a significant role in the liability of affective deficits like anhedonia.

• Tuberculosis and Respiratory Diseases
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• v.45 no.1
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• pp.116-127
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• 1998

Background: The natural course of sarcoidosis is variable from spontaneous remission to significant morbidity or death. So the assessment of disease activity is important but no single parameter was generally accepted as a good marker. Recently several studies suggested that adhesion molecules, especially ICAM-1 can be a marker, but there are some controversies. And only few data are available about the relationship of ICAM-1 with clinical follow-up course. Methods: We measured the expression of adhesion molecules on BAL cells by flow cytometry and the level of soluble ICAM-1(sICAM-1) in serum and BALF at the time of diagnosis in 12 patients with active disease and 7 inactive sarcoidosis(5 male, 14 female, mean age: $39.4{\pm}10.7$ years, mean follow-up : $20{\pm}15$ months). Follow-up clinical course were compared with the changes in serum sICAMA-1 level and the adhesion molecule on BAL cells. Results: In the patients with active disease, the ICAM-1 on AM(RMFI: $3.68{\pm}1.71$) and sICAM-1 level in serum($582{\pm}193$ng/ml) and BAL fluid($47.8{\pm}16.5$ng/ml) were all higher than those of 7 inactive disease(RMFI: $1.89{\pm}0.75$, p=0.0298, serum: $294{\pm}117$ ng/ml, p=0.0049, BALF: $20.9{\pm}8.3$ ng/ml). In the active sarcoidosis, ICAM-1 on AM(RMFI : $1.51{\pm}0.84$) and serum sICAM-1 were decreased after the therapy($250{\pm}147$ ng/ml) but no significant change was noted in inactive disease. Also we found the initial ICAM-1 on AM and serum sICAM-1 had a significant correlation with the degree of improvement in PFT after the therapy. During the follow-up, the disease relapsed in 4 patients after the discontinuation of steroid and the serum sICAM-1 level went-up again at the time of relapse. Conclusion: Our data suggest that the serum sICAM-1 level and the ICAM-1 expression on AM can be a good marker of disease activity and also a predictor of outcome in sarcoidosis.

• Journal of Intelligence and Information Systems
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• v.27 no.1
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• pp.1-21
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• 2021

As the global business environment changes, uncertainties in technology development and market needs increase, and competition among companies intensifies, interests and demands for R&D activities of individual companies are increasing. In order to cope with these environmental changes, R&D companies are strengthening R&D investment as one of the means to enhance the qualitative competitiveness of R&D while paying more attention to facility investment. As a result, facilities or R&D investment elements are inevitably a burden for R&D companies to bear future uncertainties. It is true that the management strategy of increasing investment in R&D as a means of enhancing R&D capability is highly uncertain in terms of corporate performance. In this study, the structural factors that influence the R&D capabilities of companies are explored in terms of technology management capabilities, R&D capabilities, and corporate classification attributes by utilizing data mining techniques, and the characteristics these individual factors present according to the level of R&D capabilities are analyzed. This study also showed cluster analysis and experimental results based on evidence data for all domestic R&D companies, and is expected to provide important implications for corporate management strategies to enhance R&D capabilities of individual companies. For each of the three viewpoints, detailed evaluation indexes were composed of 7, 2, and 4, respectively, to quantitatively measure individual levels in the corresponding area. In the case of technology management capability and R&D capability, the sub-item evaluation indexes that are being used by current domestic technology evaluation agencies were referenced, and the final detailed evaluation index was newly constructed in consideration of whether data could be obtained quantitatively. In the case of corporate classification attributes, the most basic corporate classification profile information is considered. In particular, in order to grasp the homogeneity of the R&D competency level, a comprehensive score for each company was given using detailed evaluation indicators of technology management capability and R&D capability, and the competency level was classified into five grades and compared with the cluster analysis results. In order to give the meaning according to the comparative evaluation between the analyzed cluster and the competency level grade, the clusters with high and low trends in R&D competency level were searched for each cluster. Afterwards, characteristics according to detailed evaluation indicators were analyzed in the cluster. Through this method of conducting research, two groups with high R&D competency and one with low level of R&D competency were analyzed, and the remaining two clusters were similar with almost high incidence. As a result, in this study, individual characteristics according to detailed evaluation indexes were analyzed for two clusters with high competency level and one cluster with low competency level. The implications of the results of this study are that the faster the replacement cycle of professional managers who can effectively respond to changes in technology and market demand, the more likely they will contribute to enhancing R&D capabilities. In the case of a private company, it is necessary to increase the intensity of input of R&D capabilities by enhancing the sense of belonging of R&D personnel to the company through conversion to a corporate company, and to provide the accuracy of responsibility and authority through the organization of the team unit. Since the number of technical commercialization achievements and technology certifications are occurring both in the case of contributing to capacity improvement and in case of not, it was confirmed that there is a limit in reviewing it as an important factor for enhancing R&D capacity from the perspective of management. Lastly, the experience of utility model filing was identified as a factor that has an important influence on R&D capability, and it was confirmed the need to provide motivation to encourage utility model filings in order to enhance R&D capability. As such, the results of this study are expected to provide important implications for corporate management strategies to enhance individual companies' R&D capabilities.

• The KIPS Transactions:PartD
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• v.10D no.6
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• pp.885-896
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• 2003

The typws of service using location Information are being various and extending their domain as wireless internet tochnology is developing and its application par is widespread, so it is prospected that LBS(Location-Based Services) will be killer application in wireless internet services. This location information is basic and high value-added information, and this information services make prior GIS(Geographic Information System) to be useful to anybody. The acquisition of this location information from moving object is very important part in LBS. Also the interfacing of acquisition of moving object between MODB and telecommunication network is being very important function in LBS. After this, when LBS are familiar to everybody, we can predict that LBS system load is so heavy for the acquisition of so many subscribers and vehicles. That is to say, LBS platform performance is fallen off because of overhead increment of acquiring moving object between MODB and wireless telecommunication network. So, to make stable of LBS platform, in this MODB system, acquisition of moving object location par as reducing the number of acquisition of unneccessary moving object location. We study problems in acquiring a huge number of moving objects location and design some acquisition model using past moving patternof each object to reduce telecommunication overhead. And after implementation these models, we estimate performance of each model.

• Journal of International Area Studies (JIAS)
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• v.15 no.1
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• pp.61-82
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• 2011

Public resistance is an essential factor of the democratization process. Due to this, public resistance has been recognized as an important element in discussing the democratization of China. Recently in China, and a new era of resistance especially the agrarian resistance has been being expanded. This paper identifies trends and characteristics of that. With searching changes in the relationship between the nation and the societies in China, we will check whether democratization can be built from the whole bottom of the nation's ideology or not. It is a paradox of china's economic growth that the peasant uprising increased is a factor to the growth. The farmers' smoldering discontent exploded with rage because rural communities have been forced to sacrifice during the growth. The authoritarian party-state system in China has been faced with the limits in calming the peasant revolt down with the traditional suppression and restriction. Even though the party-state system in China has accepted farmers' dissatisfaction somewhat, and it has tried to improve its image of a benevolent government and pursued buying stability strategy, the gap between urban and rural areas has been expanded in the sustainable economic development and modernization process, therefore the authorities could not soothe the farmers' sense of alienation. Accordingly, the peasant revolt has not flickered out easily, and has been getting uncontrolled across China. Resistance characteristics of Chinese farmers have also changed. In the past, they had been sporadic and indirect ways, whereas in recent years, they have changed into organized and active ways. Of course, it is generally evaluated that the party-state system has sustained a strong social control so far. Buying stability strategy has prevented farmers' complaints from spreading to a threat to its regime, because civil societies in rural areas have still weak foundations from being formed. The party-state system, because of tensions and conflicts, will control the growing powers of civil societies in rural areas with institutionalization of interaction between the nation and the societies, and they will induce street protests to legalized struggle for a while. However, the relationship between the state and the societies has already started new rearrangement, in terms of that the conflicts between the state and rural communities have continued, and the changes of resistance ways.

• Food Science and Preservation
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• v.16 no.6
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• pp.861-868
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• 2009

We investigated the use of mashed red pepper in the manufacture of kimchi using various freezing point depression agents (glucose, pectin, ascorbic acid or NaCl). In sensory evaluation results, overall acceptance seemed to be highly related to NaCl content. Kimchi was prepared using mashed red pepper with different levels of NaCl (3, 5, and 10% w/w), and quality characteristics were investigated during storage at $10^{\circ}C$. Salt concentrations of kimchi prepared with addition of 3, 5, or 10% NaCl, and control kimchi, were 2.28, 2.47, 3.10 and 1.92%, respectively. pH values varied significantly among treatments but acidity levels did not differ significantly except during the early stages of production. With increasing NaCl addition, the acidity of kimchi was lower than that of control samples during later fermentation periods. At day 20, the reducing sugar level in control kimchi had decreased by 70% whereas NaCl treatment caused decreases of 45 - 55%. The vitamin C contents of kimchi prepared with addition of NaCl (125.88-145.23 mg/100 g) were higher than that of control (37.22 mg/100 g). In sensory evaluation tests, appearance and texture did not differ significantly with treatment or fermentation period. When taste and overall acceptance were scored, kimchi prepared with the addition of 3% NaCl attained the highest marks throughout the entire fermentation period.