• Journal of Astronomy and Space Sciences
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• v.29 no.3
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• pp.275-285
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• 2012

In this study, we present preliminary results of precise orbit determination (POD) using satellite laser ranging (SLR) observations for International Laser Ranging Service (ILRS) Associate Analysis Center (AAC). Using SLR normal point observations of LAGEOS-1, LAGEOS-2, ETALON-1, and ETALON-2, the NASA/GSFC GEODYN II software are utilized for POD. Weekly-based orbit determination strategy is applied to process SLR observations and the post-fit residuals check, and external orbit comparison are performed for orbit accuracy assessment. The root mean square (RMS) value of differences between observations and computations after final iteration of estimation process is used for post-fit residuals check. The result of ILRS consolidated prediction format (CPF) is used for external orbit comparison. Additionally, we performed the precision analysis of each ILRS station by post-fit residuals. The post-fit residuals results show that the precisions of the orbits of LAGEOS-1 and LAGEOS-2 are 0.9 and 1.3 cm, and those of ETALON-1 and ETALON-2 are 2.5 and 1.9 cm, respectively. The orbit assessment results by ILRS CPF show that the radial accuracies of LAGEOS-1 and LAGEOS-2 are 4.0 cm and 5.3 cm, and the radial accuracies of ETALON-1 and ETALON-2 are 30.7 cm and 7.2 cm. These results of station precision analysis confirm that the result of this study is reasonable to have implications as preliminary results for administrating ILRS AAC.

• Journal of Power Electronics
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• v.18 no.2
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• pp.558-572
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• 2018

In addition to its modular nature, a Hybrid Modular Multilevel Converter (HMMC) assembled from half-bridge and full-bridge sub-modules, is able to block DC faults with a minimum number of switching devices, which makes it attractive for high power applications. This paper introduces a control strategy based on the Root-Least Square (RLS) algorithm to estimate the capacitor voltages instead of using direct measurements. This action eliminates the need for voltage transducers in the HMMC sub-modules and the associated communication link with the central controller. In addition to capacitor voltage balancing and suppression of circulating currents, a fault tolerant control unit (FTCU) is integrated into the proposed strategy to modify the parameters of the HMMC controller. On advantage of the proposed FTCU is that it does not need extra components. Furthermore, a fault detection unit is adapted by utilizing a hybrid estimation scheme to detect sub-module faults. The behavior of the suggested technique is assessed using PSCAD offline simulations. In addition, it is validated using a real-time digital simulator connected to a real time controller under various normal and fault conditions. The proposed strategy shows robust performance in terms of accuracy and time response since it succeeds in stabilizing the HMMC under faults.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.3
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• pp.109-115
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• 2011

Objectives: To characterize autonomic dysfunction in patients with Cold hypersensitivity, their heart rate variability(HRV) were measured and analyzed with cold hypersensitivity patients, compared with those of normal population. Methods: We studied 56 patients visiting Gangnam Kyung-hee korean hospital from 1st January 2010 to 31th December 2010. Heart rate variability were obtained from 28 female patients who suffer from cold hypersensitivity and 28 healthy female controls in resting state. We studied the difference of Heart rate variability between two groups by Independent T-test using SPSS for windows(version 17.0). Results: Standard deviation of NN interval(SDNN), total power(TP), Very low frequency(VLF) in patients with cold hypersensitivity were significantly different with those of controls. While no significant differences were observed in square root of mean squared differences of successive NN intervals (RMSSD), low frequency (LF) and high frequency(HF). Conclusions: The decreased values of heart rate variability(HRV) study means that they may have some kinds of imbalance in autonomic nervous system in cold hypersensitivity patients. heart rate variabiliry(HRV) study might be a tool of diagnosis and predictors in cold hypersensitivity patients.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.2
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• pp.199-202
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• 1991

Chin is located on most prominent portion of the face, so make more important esthetic value in impression. So historicaly, many authors had made efforts on correction of deformed chin, termed genioplasty. But those technique have been performed on limited cases, which have normal shape or width of chin. In the cases with more narrow or short chin, location of mental foramen or root of incisors restrict the use of such technique. But modified genioplasty technique we used can be performed without any restriction and change of frontal profile of chin. So we report a case that was performed with modified horizontal step osteotomy for advancement genioplasty, which had been reported by Hinds and Kent, with some complications.

• Journal of information and communication convergence engineering
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• v.10 no.2
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• pp.187-193
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• 2012

A 1 GHz CMOS fast-lock phase-locked loop (PLL) is proposed to support the quick wake-up time of mobile consumer electronic devices. The proposed fast-lock PLL consists of a conventional charge-pump PLL, a frequency-to-digital converter (FDC) to measure the frequency of the input reference clock, and a digital-to-analog converter (DAC) to generate the initial control voltage of a voltage-controlled oscillator (VCO). The initial control voltage of the VCO is driven toward a reference voltage that is determined by the frequency of the input reference clock in the initial mode. For the speedy measurement of the frequency of the reference clock, an FDC with a parallel architecture is proposed, and its architecture is similar to that of a flash analog-to-digital converter. In addition, the frequency-to-voltage converter used in the FDC is designed simply by utilizing current integrators. The circuits for the proposed fast-lock scheme are disabled in the normal operation mode except in the initial mode to reduce the power consumption. The proposed PLL was fabricated by using a 0.18-${\mu}m$ 1-poly 6-metal complementary metal-oxide semiconductor (CMOS) process with a 1.8 V supply. This PLL multiplies the frequency of the reference clock by 10 and generates the four-phase clock. The simulation results show a reduction of up to 40% in the worstcase PLL lock time over the device operating conditions. The root-mean-square (rms) jitter of the proposed PLL was measured as 2.94 ps at 1 GHz. The area and power consumption of the implemented PLL are $400{\times}450{\mu}m^2$ and 6 mW, respectively.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.12
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• pp.36-44
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• 2012

We had introduced the backgrounds, history and physical meanings of Jong Nang in "Jeju Jong Nang Channel Code I". In this paper, we introduce practical the root of digital human binary coded Jong Nang communications as the wooden gate in Korea Jeju Island custom. We investigate Jong Nang gatemodels as an approximation of the AWGN model. The objective is to find a deterministic model, which is accessible to capacity analysis. Furthermore, this analysis should provide insights on the capacity of the AWGN model. Motivated by backhaul cooperation in cellular networks where cooperation is among base stations, we term the interference channel with conferencing transmitters. Jong Nang communicationsis normal 3 rafters placed on two vertical stones with three holes to convey the family's whereabouts that is deterministic signal, nowadays it is applied to backhaul in mobile base station and traffic signal.

• Journal of the korean academy of Pediatric Dentistry
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• v.5 no.1
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• pp.33-38
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• 1978

It has been studied that aminoacetonitrile was associated with the inhibition of collagen fiber, argyrophilic fiber and oxytalan fiber synthesis. This experiment was performed, by the basic knowledge of above mentioned study, to study on the biological effect of aminoacetonitrile to the developing periodontal ligament in Sprague Dawley rat. twenty two of female rats weighing about 200gm were gestated. In 7 days after gestation, the experimental rats were injected aminoacetonitrile 7 times intraperitoneally. After parturition, delivered fJtuses were divided into 4 groups and each group was sacrificed to 1 day, 7 days, 14 days, and 21 days after delivery, schematically. All the fetuses were observed on their periodontal ligament by histological and histo chemical methods. To study on the components of periodontal ligament fiber in these experimental study van Gieson, Masson's trichrom, argyrophilic fiber, oxytalan fiber, methyl green pyronin and periodic acid-Shiff staining were performed. Results were as follows; 1) Retardation of functional orientation in periodontal ligament collagen fiber was observed in 1 day fetuses hut this appearance was diminished gradually and recovered in normal condition in 7 days fetuses. 2) Distribution of argyrophilic fiber in 1 day fetuses was oriented delicately and loosely but volume of this fiber was gradually thickened and distributed densely. 3) Oxytalan fiber was oriented dendritic ally and contradictorily in 14 days fetuses but their orientation was changed into oblique form in middle portion of roof and their numbers were increased gradually. 4) Pyronin-philic stain of fibroblast was gradually deepened in 7 days fetuses and this finding also suggested to the depreciation of collagen synthesis in this specimen. 5) PAS positive line was observed continuousely at the portion of cervical to the middle root surface.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.4
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• pp.704-709
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• 2006

Ectopic eruption should be understood as a change in the course of the normal eruption path of a dental bud at any moment in its origin. Transposition is a unique and extreme form of ectopic eruption. The treatment for ectopic eruption and transposition is various from simple observation to surgical exposure and orthodontic traction, according to direction of erupting tooth degree of developing root apex and eruption space etc. Autotransplantation is transplantation of tooth from one area of the mouth to another in the same individual or is moving a eruption tooth into extraction socket or surgically prepared socket, and autotransplantation is considered as a treatment of choice for the ectopic eruption when orthodontic traction is unable or when tooth movement is limited. These cases which were treated with autotransplantation of maxillary lateral incisor and maxillary canine were reported, and good esthetic and functional result were induced.

• Korean Journal of Plant Tissue Culture
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• v.26 no.1
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• pp.15-19
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• 1999

For the induction of somatic embryogenic callus, the penduncle explants of Corydalis remota for peatinata were cultured on MS basal media supplemented with 2,4-D, kinetin and zeatin. The highest embryogenic callus formation was observed on the media containing 2.0 mg/L of 2,4-D and 2.0 mg/L of zeatin. The somatic embryogenesis on the media with 0.5 mg/L of cytokinin (zeatin or kinetin) were excellent under light condition, however somatic embryos abnormally developed into plantlets. Normal dicotyledonary plantlets were found on MS medium supplemented with 1.0 mg/L of zeatin. When MS medium with 2,4-D plus cytokinin and with BAP were used, the secondary somatic embryogenesis took place in root explants of the regenerants derived from in vitro somatic embryogenic callus.

• Molecules and Cells
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• v.37 no.12
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• pp.907-911
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• 2014

The function of reactive oxygen species (ROS) as second messengers in cell differentiation has been demonstrated only for a limited number of cell types. Here, we used a well-established protocol for BMP2-induced neuronal differentiation of neural crest stem cells (NCSCs) to examine the function of BMP2-induced ROS during the process. We first show that BMP2 indeed induces ROS generation in NCSCs and that blocking ROS generation by pretreatment of cells with diphenyleneiodonium (DPI) as NADPH oxidase (Nox) inhibitor inhibits neuronal differentiation. Among the ROS-generating Nox isozymes, only Nox4 was expressed at a detectable level in NCSCs. Nox4 appears to be critical for survival of NCSCs at least in vitro as down-regulation by RNA interference led to apoptotic response from NCSCs. Interestingly, development of neural crest-derived peripheral neural structures in Nox4-/- mouse appears to be grossly normal, although Nox4-/- embryos were born at a sub-Mendelian ratio and showed delayed over-all development. Specifically, cranial and dorsal root ganglia, derived from NCSCs, were clearly present in Nox4-/- embryo at embryonic days (E) 9.5 and 10.5. These results suggest that Nox4-mediated ROS generation likely plays important role in fate determination and differentiation of NCSCs, but other Nox isozymes play redundant function during embryogenesis.