• KSBB Journal
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• v.15 no.2
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• pp.208-213
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• 2000

Using three types of porcelain clays such as White, Blue, and Yellow clays, which were used as raw materials for Bae씨a, C Chungja, and common porcelains, the biological refinement by an enrichment culture of iron reducing bacteria was studied. | In the biological clay refining, amounts of leached iron increased as increasing sucrose $\infty$ncentration, which was s supplemented as a carbon and electron donor source for cell growth and iron reduction. Total amounts of the leached iron a and specific rate of iron reduction were dependent on the types of the clay. Strength and chromaticity of refined clays which a are important properties required for porcelain clays were improved as increasing sucrose concentration. The degree of s shrinking, however, did not changed. the redness among the chromaticity of refined clays is favorably reduced through the r ripening by the iron reducing bacteria. Considering iron removal efficiency and the change of physical properties, the optimal c concentration of sucrose was 4%(w/w) in the clay.

• Journal of the Korea Institute of Building Construction
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• v.20 no.2
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• pp.163-169
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• 2020

Construction is a typical labor-dependent industry. However, problems related to wage payment, which directly affects the livelihood of workers, have caused other problems in maintaining skilled workers, such as increasing the turnover rate of skilled workers, resulting in a shortage of skilled workers. Against this backdrop, this study was conducted to develop measures to improve the conventional wage payment systems in order to prevent skilled workers from leaving their jobs and to maintain them as workers. It is necessary to make the registration of non-registered small-sized construction companies in Korea mandatory, and to introduce means by which construction companies that hire workers through non-registered agents can be penalized. In addition, the project bank account (PBA) system used in the domestic banking sector can be benchmarked in operating payment systems, an approach that is expected to effectively prevent delayed wage payments in the construction industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1265-1271
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• 2014

The lamp cooling system of the exposure has effect on the exposure efficiency and device lifetime. In this paper, we performed the numerical analysis about the thermal flow in the lamp housing of the exposure apparatus for the cooling air inflow rate. We set up the velocity of cooling air of side and bottom as the independent variables because cooling performance of the lamp housing is affected by the velocity of the cooling air side and bottom. The cooling state of lamp housing depend on three dependent variables; the temperature at top mirror and exhaust gas, ellipsoidal mirror. Response surface methodology was used in order to establish the efficient cooling analysis plan. The regression equation predicting the variables temperature of lamp housing according to the cooling air velocity were drawn. The velocity of cooling air to reach the optimum temperature of the lamp housing were derived.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.114.2-114.2
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• 2017

Transparent film heaters (TFHs) based on Joule heating are currently an active research area. However, TFHs based on an indium tin oxide (ITO) monolayer have a number of problems. For example, heating is concentrated in part of the device. Also, heating efficiency is low because it has high sheet resistance ($R_S$). Resistance of indium zinc oxide (IZO) is similar to ITO and it can be used to flexible applications due to its amorphous structure. To solve these problems, our study introduced hybrid layers of IZO/Ag/IZO deposited by magnetron sputtering, and the electrical, optical, and thermal properties were estimated for various thickness of the metal interlayer. It was found that the sheet resistance of the multilayer was mainly dependent on the thickness of the Ag layers. The $R_S$ of IZO(40)/Ag/IZO(40nm) multilayer was 5.33, 3.29, $2.15{\Omega}/{\Box}$ for Ag thickness of 10, 15, and 20nm, respectively, while the $R_S$ of an IZO monolayer(95nm) was $59.58{\Omega}/{\Box}$. The optical transmittance at 550nm for the IZO(95nm) monolayer is 81.6%, and for the IZO(40)/Ag/IZO(40nm) multilayers with Ag thickness 10, 15 and 20nm, is for 72.8, 78.6, and 63.9%, respectively. The defrost test showed that the film with the lowest RS had the highest heat generation rate (HGR) for the same applied voltage. The results indicated that IZO(40)/Ag(15)/IZO(40nm) multilayer has the best suitable property, which is a promising thin film heater for the application in vehicle windshield.

• Journal of KIISE:Information Networking
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• v.32 no.2
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• pp.254-260
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• 2005

In the guaranteed service, a real-time scheduling algorithm must achieve both high level of network utilization and scalable implementation. Here, network utilization indicates the number of admitted real-time sessions. Unfortunately, existing scheduling algorithms either are lack of scalable implementation or can achieve low network utilization. For example, scheduling algorithms based on time-stamps have the problem of O(log N) scheduling complexity where N is the number of sessions. On the contrary, round-robin algorithms require O(1) complexity. but can achieve just a low level of network utilization. In this paper, we propose a scheduling algorithm that can achieve high network utilization without losing scalability. The proposed algorithm is a Hierarchical Round-Robin (H-RR) algorithm that utilizes multiple rounds with different interval sizes. It provides latency bounds similar to those by Packet-by-Packet Generalized Processor Sharing (PGPS) algorithm using a sorted-Priority queue. However, H-RR requires a constant time for implementation.

• Asian Oncology Nursing
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• v.2 no.1
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• pp.61-71
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• 2002

Gastric Carcinoma is very plentiful and significant disease in Korean community. The reason is that Gastric Carcinoma is not a simply finding disease with unclear symptoms for early detection. Early detection and early medical treatment of a cancer patient is an important instrument of reducing the mortility rate. The purpose of this study is to identify the effect of audiovisual information with videotape infulencing on knowledge and attitude of early detection of gastric carcinoma. The research design was a non-equivalent control group, pre-post test. The subjects of this study were 52 members of D-taxi drivers which was located in Pusan. The subjects were twenty six experimental group and twenty six control group. The experimental group was collected from January 15, 1999 to January 26, 1999. The control group was collected from the research was 28 minutes video program which was turning out the form of documentary on the based practical experience. And also the experimental tool was used measurung instrument which measured a dependent, variable throughout the consulatation of an percentage, average, standard deviation, ${\chi}^2-test$ and t-test using spss/pc program. The result of this research were as follows : 1)" The experimental group which was offered the video program, should be higher in knowledge of early detection of the gastric carcinoma than the control group" was supported. (t= -7.754, p=.000) 2) "The experimental group which was offered the video program, should be higher in attitude of the early detection of the gastric carcinoma than the control group" was supported. (t=-4.321, p=.000) Therefore, in conclusion, this study that the audiovisual information with videotape influencing on knowledge and attitude of early detection of gastric carcionma was very representational experience throughout the video of documentary form on the based practical experience was much effected the change of the knowledge and the attitude regarding to the early detection of the gastric carcinoma was verified.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.726-731
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• 2000

This study was performed to evaluate the antitumor activities of water and ethanol (EtOH) extract of Salvia miltiorrhiza in vitro and in vivo. The proliferation of the human hepatoma (HepG2), rectum cancer (HRT-18) and colon cancer (HT-29) cells was inhibited by administration of extracts in a dose-dependent manner. Particularly, EtOH extract inhibited proliferation of the cells more effectively than water extract did. The morphology of cells induced by EtOH extract was characterized by reduction of cell size and deformatin. Oral administration of the EtOH extract (3 mg/head) to tumor-bearing mice inhibited the tumor (sarcoma-180) growth by 35% and prolonged their survival rate by 61%. The EtOH extract was shown to be nontoxic at 37.5% mg/head/day on the acute toxicity test. These studies suggest that the EtOH extract of Salvia miltiorrhiza may have antitumor activity in vitro and in vivo.

• Journal of Pharmaceutical Investigation
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• v.36 no.1
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• pp.39-44
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• 2006

Tamsulosin or a salt thereof such as its hydrochloride salt has been known to have an adrenaline ${\alpha}$ receptor blocking action for urethra and prostate areas. It has been widely used as a drug which lowers the prostate pressure and improves urinary disturbance accompanied by prostate-grand enlargement, thus for the treatment of prostatic hyperplasia. To avoid dose-dependent side effects of tamsulosin upon oral administration, the development of sustained-release delivery system is essentially required, that can maintain therapeutic drug levels for a longer period of time. The aim of this study was therefore to formulate sustained-release tamsulosin granules and assess their formulation variables. We designed entric coated sustained-release tamsulosin granules for this purpose. Nano-pores in the outer controlled release membrane were needed in order to obtain initial tamsulosin release even in an acidic environment such as gastric region. In our sustained release osmotic granule system, hydroxypropylmethylcellulose in a drug-containing layer was used as a rate controller. The drug-containing granules were coated with hydroxypropylmethylcellulose phthalate (HPMCP) and Eudragit, along with glycerol triacetate as an aqueous nano-pore former. The release of tamsulosin depended heavily on the type of Eudragit such as RS, RL, NE 30D, used in the formulation of controlled release layer. These results obtained clearly suggest that the sustained-release oral delivery system for tamsulosin could be designed with satisfying drug release profile approved by the Korean Food and Drug Administration.

• Journal of Microbiology and Biotechnology
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• v.23 no.6
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• pp.771-778
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• 2013

Essential oils are increasingly of interest for use as novel drugs acting as antimicrobial and antiviral agents. In the present study, we report the in vitro antiviral activities of 29 essential oils, extracted from Chinese indigenous aromatic plants, against the tobacco mosaic virus (TMV). Of these essential oils, those oils from ginger, lemon, tea tree, tangerine peel, artemisia, and lemongrass effected a more than 50% inhibition of TMV at 100 ${\mu}g/ml$. In addition, the mode of antiviral action of the active essential oils was also determined. Essential oils isolated from artemisia and lemongrass possessed potent inactivation and curative effects in vivo and had a directly passivating effect on TMV infection in a dose-dependent manner. However, all other active essential oils exhibited a moderate protective effect in vivo. The chemical constitutions of the essential oils from ginger, lemon, tea tree, tangerine peel, artemisia, and lemongrass were identified by gas chromatography and gas chromatography-mass spectrometry. The major components of these essential oils were ${\alpha}$-zingiberene (35.21%), limonene (76.25%), terpinen-4-ol (41.20%), limonene (80.95%), 1,8-cineole (27.45%), and terpinolene (10.67%). The curative effects of 10 individual compounds from the active essential oils on TMV infection were also examined in vivo. The compounds from citronellal, limonene, 1,8-cineole, and ${\alpha}$-zingiberene effected a more than 40% inhibition rate for TMV infection, and the other compounds demonstrated moderate activities at 320 ${\mu}g/ml$ in vivo. There results indicate that the essential oils isolated from artemisia and lemongrass, and the individual compound citronellal, have the potential to be used as an effective alternative for the treatment of tobacco plants infected with TMV under greenhouse conditions.

• Journal of Korean society of Dental Hygiene
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• v.20 no.5
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• pp.611-621
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• 2020

Objectives: This study aimed to verify the impact of dental health care insurance coverage policy by analyzing the changes in dental care utilization and expenditures over 5 years from 2012 to 2016, when the dental health insurance coverage expansion policy was implemented. From the national cohort data collected by the Korea Health Panel Survey, a retrospective study was conducted for all household members using dental services. Methods: This study statistically verified the difference in the dependent variables by frequency analysis, chi-square test, t-test, and one-way analysis of variance (SPSS version 22, IBM Co. USA, p<0.05). Results: The annual utilization rate steadily increased from 23.4% to 26.1% between 2012 and 2016. Although there were differences in utilization rates by gender, age, and income level, patients kept using the dental services in 2016 regardless of the type of health insurance. The average annual copayment for patient expenditures (out-of-pocket amount) increased from ￦463,844 to ￦537,401 in 2012 and 2016, respectively. Of the dental care expenditures over 5 years, the ratio of uninsured expenses by the elderly decreased from 38.5% to 25.9%, and the national health insurance service coverage increased from 40.3% to 49.1%. Conclusions: Although this policy did not reduce overall patient expenditures, it has been found that there was a positive effect on the elderly and low-income groups; it increased the utilization and access to dental services.