• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1464-1469
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• 2009

To achieve more accurate and rapid detection of macrolide-lincosamide-streptogramin B resistance genes, erm(A), erm(B), and erm(C), we developed a TaqMan probe-based real-time PCR (Q-PCR) method and compared it with conventional PCR (C-PCR), which is the most widely using erm gene identification method. The detection limit of Q-PCR was 5 fg of genomic DNA or 5-8 CFU of bacterial cells of Staphylococcus aureus. The utilization of Q-PCR might shorten the time to erm detection from 3-4 h to about 50 min. These data indicated that Q-PCR assay appears to be not only highly sensitive and specific, but also the most rapid diagnostic method. Therefore, the appropriate application of the Q-PCR assay will permit rapid and accurate identification of erm genes from clinical and other samples.

• 한국환경농학회지
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• 제30권3호
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• pp.323-329
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• 2011

BACKGROUND: The conazoles, difenoconazole, diniconazole, hexaconazole, penconazole and tetraconazole are a large class of synthetic fungicides used extensively for foliage and seed treatments in agricultural crops. The extensive use of conazoles has brought concerns on the potentiality of environmental contamination and toxicity. Thus studies on the development of methods for monitoring the conazoles are required. METHODS AND RESULTS: A modified quick, easy, effective, rugged and safe (QuEChERS) method was involved in sample preparation. Quadrapole time of flight mass spectrometer (Q-TOF MS) in electron spray ionization (ESI) mode was employed to determine conazoles in garlic samples. The limit of detection (LOD) and limit of quantification (LOQ) of conazoles by Q-TOF-MS ranged from 0.001 to 0.002 mg/L and 0.002 to 0.005 mg/L, respectively. Q-TOF-MS analysis exhibited less than 2.6 ppm error of accurate mass measurements for the detection of conazoles spiked at 0.05 mg/L in garlic matrix. Recovery values of conazoles fortified in garlic samples at 0.02, 0.05 and 0.1 mg/L were between 79.2 and 106.2% with a maximum 11.8% of standard deviation. No detectable conazoles were found in the domestic market samples by using the Q-TOF-MS method. CONCLUSION(s): High degree of confirmation for conazoles by accurate mass measurements demonstrated that Q-TOF-MS analysis combined with a QuEChERS method may be applicable to simultaneous determination of conazoles in garlic samples.

• 한국조경학회지
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• 제21권2호
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• pp.50-67
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• 1993

This study analyzed the distribution and structure of the vegetation landscape in Naejangsan National Park. The plant distribution was investigated using a field survey. There were 72 sites sampled using the clumpled sampling method. The data derived from the investigation was analyzed using the quantitative analysis of Bray-Curtis method. The analysis was performed by the classification of TWINSPAN. The ordination of DCA and RA was used for the species composition and successional trends. The results are as follows; 1. Quercus. serrata-Q. variabilis community as 21.76(16.49$\textrm{km}^2$), was the largest community in the actual vegetation of the Naejangsan National Park. The degree of green naturality index 8 area covered 64.8% of the study area and the index 6 area did 16%. 2. Classified by the ordination of DCA and environmental variables, such as the plant community was divided into seven groups according to the altitude and forming groups; Chamaecy Paris. pisifera-P.densiflora community, P.densiflora community, Q.variailis community, T.nuciofera-A.palmatum community. 3. Ther species diversity and evenness indices of C.pisifera-P.densiflora community, P.densiflora community appeared low but C.laxiflora communitywhich was the most stable community in the study area. 4. The similarity indices between Q.variabilis community and Q.serrata-Q.variabilis community were calculated 58.84%, but those between other communities were comparatively low level. 5. The successional trends of DBH class seem to be from C. pisifera-P.densiflora community, P.densiflora community to Quercus species community and from Q.variabilis community, Q.serrata-Q.variabilis community to Carpinus species community. 6. Results suggested that the successional trends in Naejangsan National Park; P.densiflora community\longrightarrowQ.variablilis community, Q.serrata-Q.variabilis community\longrightarrowC.laxiflora community in sequence.

• Journal of Forest and Environmental Science
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• 제35권4호
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• pp.232-239
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• 2019

This study was carried out to establish an efficient selection condition for cold-tolerant individuals among evergreen Quercus spp. To select higher cold-tolerant individuals among four species of evergreen Quercus spp. (Q. acuta, Q. glauca, Q. myrsinaefoila, and Q. salicina), an-year-old seedlings of each species were exposed to low temperature in serial, and then examined for the death of cell tissue and the surface temperature was monitored. It was shown that the higher numbers of seedlings of Q. myrsinaefolia were survived than the others when those seedlings are exposed to cold stress. Thus, selection of the cold tolerant individuals was conducted on Q. myrsinaefolia seedlings. The limit low temperature condition for selecting cold-tolerant individuals was -6℃ for 24 hrs because no seedling of Q. myrsinaefolia was survived after exposed to -7℃ for 24 hours. It was shown that the leaf surface temperature of the selected individuals was higher than those of the non-selected individuals when they were exposed to cold-stress while monitoring them using thermal graphic camera. The results in this study can be used for expanding afforestation area of tree species of the warm temperate zone for preparation of climate change.

• 한국보육지원학회지
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• 제13권3호
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• pp.55-81
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• 2017

Objective: The purpose of this study was to classify turnover intention of early childhood teachers. This study also analyzed the characteristics of each types of turnover intentions. The research questions were as follows: First, what are the types of turnover intention among early childhood teachers?. Second, what are the characteristics of the types of turnover intention among early childhood teachers?. Method: This study has adopted the Q methodology as a method. first, open surveys were conducted among 101 early childhood teachers and principals who work at kindergartens or child care centers along with literature research, followed by the establishment of Q samples(48 questions). Second, the Q sample was classified among the P sample and was comprised of 90 participants. Ninety early childhood teachers as P sample sorted the 48 Q statements. Results: The findings of this study were summarized as follows: First, the types of early childhood teacher's turnover intentions were identified as four-factors. Second, the characteristics of the four-types of turnover intention were interpreted as follows: 'The type of complex psychological conflict', 'The type of pursuit of social value', 'The type of dependence on organizational environment', 'The type of realistic self-development'. Conclusion/Implications: We suggested political and institutional supporting ways for each type of early childhood teachers.

• 전기학회논문지
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• 제60권2호
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• pp.362-369
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• 2011

In this paper, optimal deep reactive ion etching (DRIE) process conditions for fused quartz were experimentally determined by Taguchi method, and fused quartz-based micro cantilevers were fabricated. In addition, comparative study on Q-factors of fused quartz and silicon micro cantilevers was performed. Using a silicon layer as an etch mask for fused quartz DRIE process, different 9 flow rate conditions of $C_4F_8$, $O_2$ and He gases were tested and the optimum combination of these factors was estimated. Micro cantilevers based on fused quartz were fabricated from this optimal DRIE condition. Through conventional silicon DRIE process, single-crystalline silicon micro cantilevers whose dimensions were similar to those of quartz cantilevers were also fabricated. Mechanical Q-factors were calculated to compare intrinsic damping properties of those two materials. Resonant frequencies and Q-factors were measured for the cantilevers having fixed widths and thicknesses and different lengths. The Q-factors were in a range of 64,000 - 108,000 for fused quartz cantilevers and 31,000 - 35,000 for silicon cantilevers. The experimental results supported that fused quartz had a good intrinsic damping property compared to that of single crystalline silicon.

• 전력전자학회논문지
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• 제25권1호
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• pp.54-60
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• 2020

A digital current control scheme using virtual d-q transformation for a boost single-phase power factor correction (PFC) converter is proposed. The use of virtual d-q transformation in single-phase power converters is known to improve current control performance. However, the conventional virtual d-q transformation-based digital current control scheme cannot be directly applied to the boost single-phase PFC converter because the current and average voltage waveforms of the inductor used in the converter are not sinusoidal. To cope with this problem, this study proposes a virtual sinusoidal signal generation method that converts the current and average voltage waveform of the inductor into a sinusoidal waveform synchronized with the grid. Simulation and experimental results are provided to show that the virtual d-q transformation-based digital current control is successfully applied to the boost single-phase PFC converter with the aid of the proposed virtual sinusoidal signal generation method.

• 대한전자공학회논문지
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• 제13권3호
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• pp.7-10
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• 1976

단일 펄스의 Nd-YAG 레이저를 발생시키기 위한 Q-스인치로서 LiNbO3 크리스탈을 사용할때 생기는 난점을 해결하기 위하여 그 중계자 특성을 조사하였으며 간단한 해결 방법을 제시하였다. To eliminate some difficulties encountered in the operation of LiNbO3crystal as a Q-switch for generating a single pulse Nd-YAG laser, the operational characteristics of the crystal, was investigated. Also a simple method for solving the difficulties was presented.

• 여성건강간호학회지
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• 제9권4호
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• pp.422-431
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• 2003

Purpose: The purpose of this study was to explore the subjective opinions related to NVP experience in woman. Method: The research method used was Q-methodology. The statement of self-reference was derived from face to face interviews with 10 womans. Statement were categorized by researcher according to semantics. Twenty-seven of the self reference statement from categories of the Q-population were selected. Twenty-five of pregnant womans were selected by consideration of diversity in sociodemographic background. Based on a 1 to 9 point scale, the selected pregnant womans were made to participate in. Q-sorting. Analysis of Q-type was obtained by use of the QUANAL program. Result: There are three type of NVP experience of Korean womans. The first type focused on family support relate to NVP coping. The second type focused on physical self regulation related to NVP coping. The third type focused on actual strategy related to NVP coping. Conclusion: It is suggested that the results of this study may contribute to the development strategies for the purpose of decreasing the incidence of NVP.

• Journal of Power Electronics
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• 제7권1호
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• pp.72-80
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• 2007

Voltage sags are one of the most frequently occurring power quality problems challenging power systems today. The Unified Power Quality Conditioner (UPQC) is one of the major custom power solutions that are capable of mitigating the effect of supply voltage sags at the load or Point of Common Coupling (PCC). A UPQC-Q employs a control method in which the series compensator injects a voltage that leads the supply current by $90^{\circ}C$ so that the series compensator at steady state consumes no active power. However, the UPQC-Q has the disadvantage that its series compensator needs to be overrated. Thus it cannot offer effective compensation. This paper proposes a new control scheme for the UPQC-Q that offers minimum power injection. The proposed minimum power injection method takes into consideration the limits on the rated voltage capacity of the series compensator and its control scheme. The validity of the proposed control scheme is investigated through simulation and experimental results.