• Journal of Korean Society of Environmental Engineers
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• v.28 no.5
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• pp.563-572
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• 2006

In order to propose optimum in-situ treatment for reducing phosphorous release from sediment of stationary lakes, a series of column tests were performed. The sediment used in experiment was very fine clay with a mean grain site $7.7{\phi}$ and high $C_{org}$ contents(2.4%). Phosphorous releases were evaluated in two ways : in lake water(with microbial effect) and in distilled water(without microbial effect). As in-situ capping material, sand and loess were used while Fe-Gypsum and $SiO_2$-Gypsum were used for in-situ chemical treatment. In case of lake water considering the effect of microorganism, phosphorous concentration rapidly decreased in the early stage of experiment but it was gradually increased after 10 days. Flux of phosphorous release for control was $3.0mg/m^2{\cdot}d$. Whereas, those for sand layer capping(5 cm) and loess layer capping(5 cm) were $2.5mg/m^2{\cdot}d\;and\;1.8mg/m^2{\cdot}d$, respectively because the latter two were not consolidated sufficiently. For Fe-gypsum and $SiO_2$-gypsum the fluxes were $1.4mg/m^2{\cdot}d$ which meant that reduction efficiency of phosphorous release was more than 40% higher than that of control. The case capping with complex layer was $1.0mg/m^2{\cdot}d$, which showed high reduction efficiency over 60%. The addition of gypsum($CaSO_4{\cdot}2H_2O$) into the sediment reduced release of Phosphorus from the sediments. Gypsum acted as a slow-releasing source of sulphate in sediment, which enhanced the activity of SRB(sulfate reducing bacteria) and improved the overall mineralization rate of organic matter.

• International Commerce and Information Review
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• v.15 no.4
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• pp.457-479
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• 2013

Through a Chinese rise, Chinese dream is actualizing as the world's great power. According to outlook of World Bank and IMF, Around 2030 China will be a great power bigger than America's economic power. The rise of China will give a huge impact to the whole world. China expands her influence through a global manufacturing base and a global market. To actualize 'Peaceful Rise' Strategy, China has many constraints. Chinese society is facing many difficult social problem due to side effects of a rapid development. Such as the spread of corruption, the severity of wealth gap, environmental degradation and energy shortage. Internationally there are containment from hegemon so-called 'China threat' dispute, Taiwan issue and territorial disputes. Western countries are hostile to China for two reasons. Based on expectations, one is China's socialist system and the other is the rising China which will compete for supremacy with Europe and America. Recent emergence of Chinese nationalism and the containment of the neighboring countries are also serious limiting factors. Domestically they have the rampant corruption in the bureaucracy, weakened capacity of Communist rule, wealth disparity due to the discriminatory economic development strategy, seriousness of rural problem, social instability, lack of social security systems and the development gap between the eastern coastal areas and western inland areas, ethnic minorities problems, the constraint of sustainable development issues due to lack of resources, environmental pollution and energy constraints. Like the former Soviet Union, China may face a dismantlement. After the rise, China may encounter possibilities of a war between great powers or a collapse of Chinese society caused by deepening internal conflict. Serious economic polarization would make peasants and urban workers, who are social vulnerable people, to turn their back to communist party and threaten the justification and the appropriateness of the ruling communist party. Chinese government will think internal system security threat is more formidable risk factor than a system security threat from the hegemon. The decline of great country comes from internal reasons rather than external reasons. To achieve peaceful rise, unification with Taiwan is an essential prerequisite. Taiwan issues are complex problems which equipped with international and domestic factors. Lack of energy resources, environmental pollution in China will bring economic crisis to Korean enterprises. Important influence to Korean economy will be a changeover of the method in economic development. It will turn the balance of investment and consumption, GDP-centered growth to consumption and environment-centered growth. Services industries including finance, environment, culture, education, health care and social welfare will grow. Change in China's growth model will give a great challenge upon the intermediate goods industry in Korea. Korea should reduce the portion of machinery, automotive, semiconductor, steel and chemical-centered export industry to China, and should increase the proportion of the service industry.

• International Commerce and Information Review
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• v.15 no.4
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• pp.481-508
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• 2013

The purpose of this study is to research the specific ways of successful localization by analyzing the success and failures case for localization through the theoretical background and the strategic models of localization. The strategic models of localization are divided by management aspects such as the localization of production and sourcing, the localization of human resources, the localization of marketing, the localization of R&D, harmonious relationship with the local community and authority transfer between headquarters and local subsidiaries. And the specific measures of the successful localization are proposed within the framework of the strategic models by comparing and analyzing the success and failures case for localization of individual companies operating in Indonesia. The results indicate that there are successful companies which develop a suitable products for the local climate and failed automobile company which is weak for assembly of complete vehicle in terms of localization of production and sourcing. In case of localization of human resources, most companies recognize the importance of this part and endeavor to secure superior human resource through a related education. It is found that most of the companies perform R & D in their native country. In part of a harmonious relationship with the local community, Korean companies should contribute to the community and be friendly with local residents and make a good image of the company focusing on the cultural environment. In aspect of authority transfer between headquarters and local subsidiaries, there is a tendency to be determined by the head office rather than the joint participation. In the future, in order for Korean enterprise to be successful one in Indonesia market, a highly interdependent and complex forms between headquarters and local subsidiaries shall be performed and an active exchange of information and the selection of best talent regardless of nationality shall be promoted.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.05a
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• pp.91-93
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• 2003

A comprehensive numerical study is carried out to investigate for the understanding of the flow evolution and flame development in a supersonic combustor with normal injection of ncumally injecting hydrogen in airsupersonic flows. The formulation treats the complete conservation equations of mass, momentum, energy, and species concentration for a multi-component chemically reacting system. For the numerical simulation of supersonic combustion, multi-species Navier-Stokes equations and detailed chemistry of H2-Air is considered. It also accommodates a finite-rate chemical kinetics mechanism of hydrogen-air combustion GRI-Mech. 2.11[1], which consists of nine species and twenty-five reaction steps. Turbulence closure is achieved by means of a k-two-equation model (2). The governing equations are spatially discretized using a finite-volume approach, and temporally integrated by means of a second-order accurate implicit scheme (3-5).The supersonic combustor consists of a flat channel of 10 cm height and a fuel-injection slit of 0.1 cm width located at 10 cm downstream of the inlet. A cavity of 5 cm height and 20 cm width is installed at 15 cm downstream of the injection slit. A total of 936160 grids are used for the main-combustor flow passage, and 159161 grids for the cavity. The grids are clustered in the flow direction near the fuel injector and cavity, as well as in the vertical direction near the bottom wall. The no-slip and adiabatic conditions are assumed throughout the entire wall boundary. As a specific example, the inflow Mach number is assumed to be 3, and the temperature and pressure are 600 K and 0.1 MPa, respectively. Gaseous hydrogen at a temperature of 151.5 K is injected normal to the wall from a choked injector.A series of calculations were carried out by varying the fuel injection pressure from 0.5 to 1.5MPa. This amounts to changing the fuel mass flow rate or the overall equivalence ratio for different operating regimes. Figure 1 shows the instantaneous temperature fields in the supersonic combustor at four different conditions. The dark blue region represents the hot burned gases. At the fuel injection pressure of 0.5 MPa, the flame is stably anchored, but the flow field exhibits a high-amplitude oscillation. At the fuel injection pressure of 1.0 MPa, the Mach reflection occurs ahead of the injector. The interaction between the incoming air and the injection flow becomes much more complex, and the fuel/air mixing is strongly enhanced. The Mach reflection oscillates and results in a strong fluctuation in the combustor wall pressure. At the fuel injection pressure of 1.5MPa, the flow inside the combustor becomes nearly choked and the Mach reflection is displaced forward. The leading shock wave moves slowly toward the inlet, and eventually causes the combustor-upstart due to the thermal choking. The cavity appears to play a secondary role in driving the flow unsteadiness, in spite of its influence on the fuel/air mixing and flame evolution. Further investigation is necessary on this issue. The present study features detailed resolution of the flow and flame dynamics in the combustor, which was not typically available in most of the previous works. In particular, the oscillatory flow characteristics are captured at a scale sufficient to identify the underlying physical mechanisms. Much of the flow unsteadiness is not related to the cavity, but rather to the intrinsic unsteadiness in the flowfield, as also shown experimentally by Ben-Yakar et al. [6], The interactions between the unsteady flow and flame evolution may cause a large excursion of flow oscillation. The work appears to be the first of its kind in the numerical study of combustion oscillations in a supersonic combustor, although a similar phenomenon was previously reported experimentally. A more comprehensive discussion will be given in the final paper presented at the colloquium.

• Journal of the Korean earth science society
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• v.30 no.6
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• pp.744-758
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• 2009

The characteristics of brightness temperature (BT) of infrared and water vapor channels from MTSAT-1R have been investigated using 12 persistent and frequent lightning cases selected from the summer lightnings of 2006-2008. The infrared (IR1, 10.3-11.3 ${\mu}M$) and water vapor (WV, 6.5-7.0 ${\mu}M$) channels from the MTSAT-1R and the lightning observation data from Korea Meteorological Administration are used. When there is no lightning, the BTs of the IR1 and WV channels show the largest frequency at around 290-295K and 245K, respectively. On the other hand, the BTs of two channels show the largest frequency at 215K caused by strong convection when there is lightning. As a result, the WV-IR1 difference (BTDWI) sharply increases from -50K to 0K. Although it depends on the evolution stage of thunderstorms, the lightning mainly occurs at the core of circular convection in the mesoscale convective complex (MCC), whereas the lightning occurs by concentrated line-shape in the squall line. A strong positive correlation exists between the lightning frequency and the BT in the MCC regardless of the BT, but only at the very cold BT in the squall line. In general, the characteristics of BT are well defined for the lightning occurring in the concentrated line, but they are not well defined in the MCC, especially during the decaying stage of MCC. When they are defined well, the lightning occurs when the BTs of IR1 and WV are lower than 215K, BTDWI is near -3 to 1K, and local standard deviation of IR1 decreases to around 1K.

• Journal of Oral Medicine and Pain
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• v.34 no.4
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• pp.341-351
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• 2009

There is tremendous variability in the ways patients present with taste problems. Because of complex and multifactorial etiological background, it is not simple to evaluate patients with taste disorders. Accurate assessment of patients' status by prudent, thorough history taking and symptom analysis is the most essential for exact diagnosis of taste disorders. The aim of this study was to investigate the clinical characteristics of patients with taste problems as a primary complaint. Consecutive series of 50 patients (12 males and 38 females, mean age $53.6\;{\pm}\;14.7$ years) were included for the present study. All subjects were requested to complete a comprehensive questionnaire. Clinical evaluation procedures included oral examination, interview, questionnaire analysis, panoramic radiography, blood test and measurement of salivary flow rate. The obtained results were as follows: 1. Among the patients, 36 patients (72%) complained of oral mucosal pain or burning sensation. Of these patients, 18 patients (36%) were diagnosed as burning mouth syndrome. 2. Nineteen patients (38%) complained of subjective oral dryness. The flow rate of unstimulated whole saliva was less than 0.1 mL/min in 14 patients (28%) and 17 (34%) had a stimulated whole salivary flow rate of less than 0.5 mL/min. 3. Among the types of taste disorders, hypogeusia, the most frequently reported, was found in 25 patients (50%), dysgeusia in 18 patients (36%), phantogeusia in 15 patients (30%), hypergeusia in 10 patients (20%), and ageusia in 5 patients (10%). Nineteen patients (38%) reported more than one type of taste disorder and the most frequent combination was dysgeusia + hypogeusia (n=6, 12%). 4. Based on data from the medical and dental histories and examinations, the patients were assigned to 12 probable causal categories. Taste disorders due to oral mucosal diseases and idiopathic taste disorder were the most frequent (n=9; 18%, each), followed by psychogenic taste disorder (n=8; 16%), drug-induced taste disorder (n=7; 14%), and taste disorder due to dry mouth (n=6; 12%). These 5 categories of taste disorder accounted for 78% of all cases in this study.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.2
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• pp.163-173
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• 2013

When the mandible performs opening movement, the condyle-disk complex conducts sliding movement along the articular eminence. Thus, anatomic configuration of articular eminence is very important to normal movement of TMJ. The purpose of this study was to measure the posterior slope of the articular eminence and evaluate the effect of a pathologic bone change in the condylar head on the stiffness of articular eminence, and compare the differences of the articular eminence slope by gender and age using dental cone-beam CT. As using i-CAT Cone-Beam Computed Tomography, the CT images of 204 TMJs of 102 patients(43 men and 59 women, mean age: 37.7 years) who were diagnosed at Wonkwang University Sanbon Dental Hospital were evaluated. All images were converted into a TMJ analysis mode to observe the continuous sagittal section images and coronal section images of the joints. To observe and assess bone changes in the condyle, three dentists measured the stiffness of the articular eminence on the same images, and when two of the three dentists agreed on their reading, these results were adopted and recorded. The articular eminence slope, considering the condylar anatomic configuration, was measured in three regions, namely, lateral part, central part, and medial part of the condyle. In the cases of a normal condyle(NCBC) and a condyle(CBC) with bone change, the articular eminence slopes were $57.0^{\circ}$(NCBC) and $51.8^{\circ}$(CBC) at the medial part, $57.9^{\circ}$(NCBC) and $52.4^{\circ}$(CBC) at the central part, and $55.1^{\circ}$(NCBC) and $49.5^{\circ}$(CBC) at the lateral part of the condyle. And the articular eminence slope of the condyle with bone change demonstrated less steepness than that of normal condyle (p<0.05). The articular eminence slope showed mediolaterally that it was the steepest at the central, followed by at the medial, and at the lateral (p<0.05). There were no significant differences by the gender and the age (p.0.05).

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1214-1222
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• 1998

Background : The intrapleural hypofibrinolysis is caused by mainly excessive concentration of pleural plasminogen activator inhibitor-1 antigen(PAI-1 Ag), which binds tissue type plasminogen activator. In pleural inflammation induced by sclerosing agents for pleurodesis, levels of pleural PAI-1 antigen increase in relation to decreasing D-dimer levels. It has been known that the pleural mesothelial cells have the capability of secreting PAI-1 Ag in response to inflammation in vivo. Therefore, we estimated whether pleural inflammation changes the balance between fibrinolytic and coagulative properties in exudative pleural effusions. Method : The thirty cases was included in our study. We determined the pleural levels of glucose, lactic dehydrogenase(LDH), pH and the counts of white blood cell(WBC), polymorpho leukocyte(PMN), lymphocyte as the parameters of pleural inflammation and cellular components of pleural fluid. The plasma level of fibrinogen in fluid and the neutrophil count in blood were determined. The levels of D-dimer, PAI-1 Ag and thrombinantithrombin III complex(TAT) were determined by ELISA(Behring, Marburg, Germany). Result : The causes of pleural effusion were as following : tuberculous in 14 cases, malignant in 10 cases and parapneumonic in 6 cases. The levels of pleural D-dimer, PAI-1 Ag and TAT was significantly higher than that of plasma(p<0..001). The severity of pleural inflammation did not correlated with pleural D-dimer, PAI-1 Ag, TAT and their plasma levels. But the level of pleural TAT correlated with pleural WBC and lymphocyte count. Conclusion : We found that the severity of pleural inflammations did not correlated with pleural D-dimer, PAI-1 Ag, TAT and the possibility of local production of PAI-1 antigen is present.

• Tuberculosis and Respiratory Diseases
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• v.49 no.5
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• pp.558-567
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• 2000

Background : Recently, serologic techniques for tuberculosis have been developed and some of them, which are focusing on detection of serum antibodies mainly directed against specific 38-kDa Mycobacterium tuberculosis, have already been introduced into the markel. In this study, diagnostic significance of a new serologic test(ELISA kit) for pulmonary tuberculosis was evaluated. Method : Serologic test with newly developed ELISA kit was performed upon 474 individuals, who include 333 active pulmonary tuberculosis patients, 80 healthy cases, and 61 tuberculosis contact cases. This serologic test was based on the ELISA technique and designed to detect antibodies to mixed complex antigens including 38-kDa, which were developed by Erume Biotech Co., Seoul. Active pulmonary tuberculosis was diagnosed by sputum AFB smear and culture methods. Results : The seropositivities using this ELISA kit were 82.1% and 73.6% in smear-positive and negative groups among active pulmonary tuberculosis, respectively. And, it also showed that seronegativities were 97.5% and 85.2% in healthy and contact groups, respectively. As a whole, the results of our study using the ELISA kit as a diagnostic method for pulmonary tuberculosis showed 80.0% sensitivity for active pulmonary tuberculosis, 97.5% specificity, 96.1% positive predictive value, and 65.0% negative predictive value when the prevalence of tuberuclosis in the samples was 60.1%. Conclusion : Our results reveal that the detection of antibody its reaction with 38-kDa antigen of M. tuberculosis is not sufficient to be accepted as single diagnostic method for pulmonary tuberculosis. However, they suggest that ELISA kit may be considered as an adjunctive test to standard diagnostic techniques of pulmonary tuberculosis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.470-486
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• 1995

Mammary epithelial cells contain a subpopulation of cells with a large proliferativ potential which are responsible for the maintenance of glandular cellularity and are the progenitor cells of mammary cancer. These clonogens give rise to multicellular clonal alveolar or ductal units(AU or DU) on transplantation and hormonal stimulation. To isolate putative mammary clonogens, enzymatically monodispersed rat mammary epithelial cells from organoid cultures and from intact glands are sorted by flow cytometry according to their affinity for FITC labeled peanut lectin(PNA) and PE labeled anti-Thy-1.1 antibody(Thy-1.1) into four subpopulations : cells negative to both PNA and Thy-1.1(B-), PNA+cells, Thy-1.1+cells, and cells positive to both reagents(B+). The in vivo transplantation assays indicate that the clonogenic fractions of PNA+cells from out-growths of organoids in primary cultures for three days in complete hormone medium(CHM) are significantly higher than those of cells from other subpopulations derived from cultrues or from intact glands. Extracellular matrix(ECM) is a complex of several proteins that regulated cell function ; its role in cell growth and differentiation and tissue-specific gene expression. It can act as a positive as well as a negative regulator of cellular differentiation depending on the cell type and the genes studied. Regulation by ECM is closely interrelated with the action of other regulators of cellular function, such as growth factors and hormones. Matrigel supports the growth and development of several different multicellular colonies from mammary organoids and from monodispersed epithelial cells in culture. Several types of colonies are observed including stellate colonies, duct-like structures, two- and three-dimensional web structures, squamous organoids, and lobulo-duct colonies. Organoids have the greatest proliferative potential and formation of multi-cellular structures. Phase contrast micrographs demonstrate extensive intracellular lipid accumulation within the web structures and some of duct-like colonies. At the immunocytochemical and electron micrograph level, casein proteins are predominantly localized near the apical surface of the cells or in the lumen of duct-like or lobulo-duct colonies. Squamous colonies are comprised of several layers of squamous epithelium surrounding keratin pearls as is typical fo squamous metaplasia(SM). All-trans retinoic acid(RA) inhibits the growth of SM. The frequency of lobulo-ductal colony formation increased with the augmentation of RA concentration in these culture conditions. The current study models could provide powerful tools not only for understanding cell growth and differentiation of epithelial cells, but also for the isolation and characterization of mammary clonogenic stem cells.