• Advances in Traditional Medicine
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• v.2 no.1
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• pp.64-67
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• 2002

In the course of screening for new anticancer antibiotics from myxobacteria, strain JW357 was found to produce an antibiotic that was active against several human cancer cell lines. This strain was identified as Angiacaccus disciformis by morphological and cultural characteristics. The antibiotic produced was identified as myxochelin A. It demonstrated significant cytotoxicity against certain human cancer cells with $IC_{50}$ values ranging 1.15 to $2.36{\mu}g/ml$. Myxochelin A was interestingly as active against multidrug-resistant CL02 cells as against the sensitive parental cells (HCT15).

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.11-14
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• 1990

The Complex Harmonic Balance Finite Element Method CHBFEM ) is dicussed for the time - periodic magnetic field with saturation characteristics. And Jw - method which is used for analyzing liner system with sinusoidal voltage input can be generalized in nonlinear time-periodic magnetio field system. The CHBFEM enables us to calculate the each harmonic magnetic flux ditribution and the distortion of currents resulting from material at an AC voltage source and to save calculating time, the number of calculation and computer memory.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2648-2650
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• 2000

The PID tuning algorithm which can be applied generally to processes with varies dynamic characteristics is proposed by Wang[7]. However, it can be applied well to process model without zeros and with $\angle$G(jw)=-${\pi}$/2 and -${\pi}$ point in Nyquist curve, but it gives unsatisfactory tuning performance for processes with zeros and without $\angle$G(jW)=-${\pi}$/2 and -${\pi}$ in Nyquist curve. In this paper, the method which improve it using Pade reduction method is proposed. Satisfactory responses can be expected for processes with various dynamics, including those with low or high order, small or large dead time, monotonic or oscillatory responses. Simulation examples are given to show the effectiveness and flexibility of the controller in handling processes of different characteristics.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.4
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• pp.833-841
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• 1997

In this paper, the hybrid LB-TJW(Leaky Bucket-Triggered Jumping Window) algorithm for multimedia traffic control is proposed and its performance is evaluated and analyzed. Its architecture is composed of the peak bit rate controller and the average bit rate controller. Generally, the cell which violates the peak bit rate is discraded in LBalgorithm, and the average bit rate of JW or TJW algorithm is better than that of LB algorithm. However, the hybrid LB-TJW algorithm passes it though the network if the cell does not violate the peak bit rate. If the cell violates the peak bit rate, the hybrid LB-TJW algorithm passes it to the average bit rate controller which perforithm to monitor the average bit rate of input traffic. The TJW algorithm monitors the cell that violates the average bit rate. If the cell does not violate the average bit rare, the LB-TJW algorithm passes it through the network. As simulation results, the cell loss rate and the buffer size of the LB-TJW algorithm is reduced to half as much as those of LB algortihm.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.1
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• pp.74-82
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• 1986

The elliptic functions have a set of zeros on the jw axis. In acitve realization we decompose a function into product of biquads. In this paper, a simple method of pole-zero pairing is proposed for the enhancement of overall dynamic range. Secondly, the optimum sequencing of individual biquads is developed and it is demonstrated that the commonly accepted sequencing technique does not hold in the case of elliptic functions. This work is an approximation for Leuder's(1970)method.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.73-74
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• 2020

In this study, the feasibility of the durometer into super retarding concrete was studied by comparing the penetration resistance with the hardness of each durometer using the penetration resistance and the improved Durometer and Durometer A-Type according to the ultra-delay mixture rate. The test results showed that initial setting time by improved Durometer and Durometer A-Type were fixed at 25, 50 HD, respectively, and the 35, 80 HD showed at final setting time. It was also found that the use of the durometer can be available to measure the setting time of the concrete.

• The Journal of Advanced Prosthodontics
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• v.10 no.2
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• pp.79-84
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• 2018

PURPOSE. All-ceramic restorations required extensive tooth preparation. The purpose of this in vitro study was to investigate a minimally invasive preparation and thickness of monolithic zirconia crowns, which would provide sufficient mechanical endurance and strength. MATERIALS AND METHODS. Crowns with thickness of 0.2 mm (group 0.2, n=32) or of 0.5 mm (group 0.5, n=32) were milled from zirconia and fixed with resin-based adhesives (groups 0.2A, 0.5A) or zinc phosphate cements (groups 0.2C, 0.5C). Half of the samples in each subgroup (n=8) underwent thermal cycling and mechanical loading (TCML)(TC: $5^{\circ}C$ and $55^{\circ}C$, $2{\times}3,000cycles$, 2 min/cycle; ML: 50 N, $1.2{\times}10^6cycles$), while the other samples were stored in water ($37^{\circ}C/24h$). Survival rates were compared (Kaplan-Maier). The specimens surviving TCML were loaded to fracture and the maximal fracture force was determined (ANOVA; Bonferroni; ${\alpha}=.05$). The fracture mode was analyzed. RESULTS. In both 0.5 groups, all crowns survived TCML, and the comparison of fracture strength among crowns with and without TCML showed no significant difference (P=.628). Four crowns in group 0.2A and all of the crowns in group 0.2C failed during TCML. The fracture strength after 24 hours of the cemented 0.2 mm-thick crowns was significantly lower than that of adhesive bonded crowns. All cemented crowns provided fracture in the crown, while about 80% of the adhesively bonded crowns fractured through crown and die. CONCLUSION. 0.5 mm thick monolithic crowns possessed sufficient strength to endure physiologic performance, regardless of the type of cementation. Fracture strength of the 0.2 mm cemented crowns was too low for clinical application.

• Perspectives in Nursing Science
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• v.15 no.2
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• pp.49-69
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• 2018

Purpose: The purpose of this study was to derive contextual indicators of medical provider quality and assess their relative importance along with the individual utilization of antenatal care (ANC) and institutional births with a skilled birth attendant (SBA) in India using a multilevel framework. Methods: The 2015~2016 Demographic and Health Survey (DHS) from India was used to assess the outcomes of neonatal, infant, and under-five child mortality. The final analytic sample included 182,980 children across 28,283 communities, 640 districts, and 36 states and union territories. The contextual indicators of medical provider quality for districts and states were derived from the individual-level number of ANC visits (<4 or ${\geq}4$) and institutional delivery with SBA. A series of random effects logistic regression models were estimated with a stepwise addition of predictor variables. Results: About half of the mothers (47.3%) had attended ${\geq}4$ ANC visits and 75.8% delivered in institutional settings with SBAs. Based on ANC visits, 276~281 districts (43.1~43.9%) and 13~16 states (36.5~44.4%) were classified as "low" quality areas, whereas 268~285 districts (41.9~44.5%) and 8~9 states (22.2~25.0%) were classified as "low" quality areas based on institutional delivery with SBAs. Conditional on a comprehensive set of covariates, the individual use of both ANC and SBA were significantly associated with all mortality outcomes (OR: 1.17, 95% CI: 1.08, 1.26, and OR: 1.10, 95% CI: 1.02, 1.19, respectively, for under-five child mortality) and remained robust even after adjusting for contextual indicators of medical provider quality. Districts and states with low quality were associated with 57~61% and 27~43% higher odds of under-five child mortality, respectively. Conclusion: When simultaneously considered, district- and state-level provider quality mattered more than individual access to care for all mortality outcomes in India. Further investigations are needed to assess the importance of improving the quality of health service delivery at higher levels to prevent unnecessary child deaths in developing countries.

• The Korean Journal of Mycology
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• v.44 no.3
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• pp.138-144
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• 2016

Twelve unrecorded yeasts, Pseudozyma prolifica HL9-1, Trichosporon coremiiforme NS19-2, Candida cretensis SA4-1, Cryptococcus diffluens TJ4-3, Cryptococcus pinus YB17-2, Candida vartiovaarae DD2-5, Pichia galeiformis DM3-5, Candida pseudolambica JW2-3, Trichosporon xylopini NS5-1, Trichosporon moniliiforme NS5-7, Tetrapisispora iriomotensis NS14-2, and Tetrapisispora nanseiensis SA17-1, were screened among 97 yeasts from soils of Chungcheongnam-do and Daejeon metropolitan city, Korea. These yeasts were oval or ellipsoidal and had a budding system for vegetative reproduction. They grew well in yeast extract-peptone-dextrose (YPD) medium and, in particular, Tetrapisispora iriomotensis NS14-2 and Candida cretensis SA4-1 grew well in 10% NaCl-containing YPD broth. Nine strains, including Trichosporon coremiiforme NS19-2, assimilated xylose and four yeast strains, such as Candida vartiovaarae DD2-5, also assimilated lactose. Physiological functionalities of cell-free extracts and supernatants from two halophilic unrecorded yeasts, Candida cretensis SA4-1 and Tetrapisispora iriomotensis NS14-2, were investigated. Cell-free extracts from Candida cretensis SA4-1 and Tetrapisispora iriomotensis NS14-2 exhibited 71.3% and 68.4% antihypertensive angiotensin I-converting enzyme inhibitory activity.

• Journal of Science Education
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• v.45 no.1
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• pp.69-89
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• 2021

The purpose of this study is to examine personal characteristics of two elementary students who developed individual interest in science. 201 students of two elementary schools in Seoul participated in questionnaire survey engaged in to investigate students' interest in science, engagements and preference in science-related-activities three times a year. This case study was conducted with seven students who showed typical types of interest in science. Students wrote a photo-journal for 12 weeks. They were interviewed every other week by a researcher. We analyzed two students who developed individual interest. It turns out that RF participated in doing experiments at home, and disassembling and assembling things. Participation of activities was a process of solving curiosity. When he was unable to solve problems, he searches the internet or books. Sometimes he would ask for help from his teacher. JW engaged in activities: drawing, doing experiments at home, and going to informal education center. She communicated with others by using online-offline media. Curious questions were solved by herself. The two students have a tendency to solve problems by themselves. Also, positive science-related activities were going on at home and in school. This study not only give insights and understanding of students who developed individual interest in science but also provide implication for educators to examine personal characteristics of students.