• Journal of Advanced Navigation Technology
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• v.26 no.6
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• pp.404-411
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• 2022

The main function in operating the satellite navigation system is to accurately determine the orbit of the navigation satellite and transmit it as a navigation message. In this study, we developed software to determine the orbit of a navigation satellite by combining an extended Kalman filter and an accurate dynamic model. Global positioning system (GPS) and quasi-zenith satellite system (QZSS) orbit determination was performed using international gnss system (IGS) ground station observations and user range error (URE), a key performance indicator of the navigation system, was calculated by comparison with IGS precise ephemeris. When estimating the clock error mounted on the navigation satellite, the radial orbital error and the clock error have a high inverse correlation, which cancel each other out, and the standard deviations of the URE of GPS and QZSS are small namely 1.99 m and 3.47 m, respectively. Instead of estimating the clock error of the navigation satellite, the orbit was determined by replacing the clock error of the navigation message with a modeled value, and the regional correlation with URE and the effect of the ground station arrangement were analyzed.

• Journal of Biomedical Engineering Research
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• v.27 no.6
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• pp.392-401
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• 2006

Image Guided Surgery (IGS) system which has variously tried in medical engineering fields is able to give a surgeon objective information of operation process like decision making and surgical planning. This information is displayed through 3D images which are acquired from image modalities like CT and MRI for pre-operation. The technique of image registration is necessary to construct IGS system. Image registration means that 3D model and the object operated by a surgeon are matched on the common frame. Major techniques of registration in IGS system have been used by recognizing fiducial markers placed on the object. However, this method has been criticized due to additional trauma, its invasive protocol inserting fiducial markers in patient's bone and generating noise data when 2D slice images are acquired by image modality because many markers are made of metal. Therefore, this paper developed shape-based registration technique to improve the limitation of fiducial marker based IGS system. Iterative Closest Points (ICP) algorithm was used to match corresponding points and quaternion based rotation and translation transformation using closed form solution applied to find the optimized cost function of transformation. we assumed that this algorithm were used in Total Knee replacement (TKR) operation. Accordingly, we have developed region-based 3D registration technique based on anatomical landmarks and this registration algorithm was evaluated in a femur model. It was found that region-based algorithm can improve the accuracy in 3D registration.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.269-270
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• 1998

Image-guided surgery (IGS) system has become well known in the field of neurosurgery and spine surgery. A patient's anatomy is first registered to preoperatively acquired CT/ MRI data using the point matching algorithm. A magnetic field digitizer was used to measure the physical space data and the system was based on Workstation of Unix system. To evaluate the spatial accuracy of interactive IGS system, the phantom consisting of rods varied height and known location was used. The RMS error value between CT/MR images and real location was 3-4mm. For the more convenience of the surgery, we provide various image display modules.

• Journal of Microbiology and Biotechnology
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• v.5 no.4
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• pp.194-199
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• 1995

A portion (7.4 kb) of ribosomal DNA tandem repeat unit from a genome of the mushroom T. matsutake has been cloned. A 1.75 kb EcoRI fragment was cloned first using S. cerevisiae 255 rRNA gene as a probe, and this was then used for further cloning. A chromosomal walking experiment was carried out and the upstream region of the 1.75 kb fragment was cloned using SmaI/BamHI enzyme, the size was estimated to be 5.2 kb in length. Part of the downstream region of the 1.75 kb fragment was also cloned using XbaI/BamHI enzymes. Restriction enzyme maps of three cloned DNA fragments were constructed. Northern hybridization, using total RNA of T. matsutake, and the restriction fragments of three cloned DNAs as probes, revealed that all four ribosomal RNA genes (large subunit[LSU], small subunit [SSU], 5.85 and 5S rRNA genes) are present in the cloned region. The gene organization of the rDNA are regarded as an intergenic spacer [IGS]2 (partial) - SSU rRNA - internal transcribed spacer [ITS]1 - 5.8S rRNA - ITS2 - LSU rRNA - IGS1 -5S rRNA - IG52 (partial).

• Journal of Species Research
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• v.10 no.2
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• pp.154-158
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• 2021

An endemic endangered species, Aster altaicus var. uchiyamae (Danyang aster) B2015-0044, is cultivated at the Shingu Botanical Garden, which serves as the ex situ conservation institution for this species. In this work, we sequenced the chloroplast genome of A. altaicus var. uchiyamae B2015-0044. We found that the chloroplast (cp) genome of B2015-0044 was 152,457 base pairs(bps) in size: 84,247 bps of large single copy regions(LSC), 25,007 bps of inverted repeats(IRs), and 18,196 bps of small single copy regions. The B2015-0044 cp genome contains 79 protein-coding genes (PCGs), 4 RNA genes, 29 tRNA genes, and 3 pseudogenes. These results were identical to a previously reported cp genome (Park et al., 2017), except for two sites in introns and three in intergenic spacer (IGS) regions. For the intronic differences, we found that clpP.i1 had a 1-bp small simple repeat (SSR) (T) and petD.i had a 3-bp SSR (ATT). We found 1-bp SSRs in the IGSs of trnT_ggu~psbD and psbZ~trnG_gcc, C and A, respectively. The IGS of(ndhF)~rpl32 had a SNP. Based on our results, the cp genome of the A. altaicus var. uchiyamae can be classified into two genotypes, [C]¹-[A]¹²-[T]¹²-[ATT]⁴-C and [C]²-[A]¹¹-[T]¹¹-[ATT]²-A.

• Journal of Positioning, Navigation, and Timing
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• v.9 no.3
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• pp.229-236
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• 2020

The trend of water vapor contents in atmosphere is one of key elements for studying climate change. The tropospheric products, i.e., ZTD values achieved through GPS data processing can retrieve the amount of water vapor with higher temporal and spatial resolution than any other instruments. In this study, the tropospheric products of KASINET for a time period from 2001 to 2014 are reprocessed using PPP strategy and the products from the CODE's 2nd reprocessing campaign. For consistency with reprocessing activities of other networks like EPN, the VMF1 mapping function and non-tidal loading effect due to atmospheric pressure are applied in the process. The reprocessing results are investigated through comparing with the CODE's 2nd reprocessing products by including some IGS stations in the process and also calculating weekly coordinate repeatability to see the quality of the processing. After removing outliers based on the variation of averaged formal error, all processed stations have similar variations of formal error about 2 mm which is lower than that of the IGS final product. Comparison results with the CODE's 2nd reprocessing products show that the overall mean difference is found to be -0.28±5.54 mm which is similar level of the previous studies. Finally, the ZTD trends of all KASINET stations are calculated and the averaged trend is achieved as 0.19 mm/yr. However, the trend of each month shows different amounts and directions from -1.26 mm/yr in May to 1.18 mm/yr in August. In conclusion, the reprocessed tropospheric product and applied strategy of this study has enough quality as one of reliable solution for a reference product for Korean Peninsula which is needed to use GPSbased tropospheric product for climate change research.

• Journal of Life Science
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• v.8 no.1
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• pp.32-39
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• 1998

The length and G/C concent of regions of an aphid rDNA unit that spans 13,061bo with 59% G/C content. flolowing belowing below are the those results, 5’ETS is 843bp in length with 69% G/C content, 18S is 2,469bp in length with 59% G/C content, ITS I is 229bp in length with 70% G/C content, 5.8S is 160bp in length with 63% G/C content, ITS II is 325bp in length with 70% G/C content, 28S is 4, 147bp in length with 60% G/C content, IGS is 4,888bp in length with 55% G/C content.

• Korean Journal of Plant Taxonomy
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• v.41 no.4
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• pp.353-360
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• 2011

The sequence data of the plastid DNA (trnL-F IGS, trnL intron, and trnH-psbA) and nuclear DNA (RNApol2_i23) markers were utilized to study phylogenetic relationships among the taxa in the Polygonatum odoratum complex (Ruscaceae). European P. odoratum individuals form a clade with a high bootstrap value, which is a sister to the clade of Korean P. odoratum var. odoratum, P. odoratum var. pluriflorum and P. robustum. The formation of the clade with P. odoratum var. odoratum, P. robustum, and one accession of P. odoratum var. pluriflorum indicates geological speciation in isolated populations in the islands following dispersal events from the mainlands. All data sets form two major clades, which are congruent with the subgroups divided by the basic chromosome numbers (x = 9 and x = 10). Although it is not easy to test the hypothesis of the decrease in the basic chromosome number due to scatter taxon sampling in this study, the molecular data strongly suggested that aneuploidy plays an important role in lineage diversification in the genus Polygonatum. The cytological data was not strongly supported by the cpDNA sequences. Further investigations of the cytological, morphological, and geographical characteristics with comprehensive sampling are desired to understand the evolution and lineage diversification in the genus.

• Korean Journal of Microbiology
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• v.36 no.4
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• pp.249-253
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• 2000

The genetic diversity among Korean cyanobacteria was assessed by restriction fragment length polymorphism(RFLP) analysis of PCR products from the phycocyanin locus. Strains of all the genera tested were successfully amplified, and the size of amplified fragments was approximately 700bp. The restriction patterns generated by AluI, MspI, and HaeIII were conserved for strains within each of genera studied and were specific to the genus level. Intrageneric delineation of strains was revealed by the enzyme, CfoI for members of genera Anabeana and Synechocystis. Phenogram derived from the different RFLP patterns revealed a coherent cluster among Anabeana, Chlorogloea, and Synechocystis strains. PC-RFLP methods provided useful tools for classification of cyanobacteria.

• Bulletin of the Korean Chemical Society
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• v.29 no.10
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• pp.1937-1940
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• 2008

The P1 duplex of Tetrahymena group I ribozyme is the important system for studying the conformational changes in folding of ribozyme. The formation of the P1 duplex between IGS and substrate RNA and the catalytic activity of ribozyme require a variety of metal ions such as $Mg^{2+}$ and $Mn^{2+}$. In order to investigate the effect of the $Mg^{2+}$ concentration on the conformation of the P1 duplex, the NMR study was performed as a function of $Mg^{2+}$ concentration. This study revealed that the less stable AU-rich region formed duplex at $50{^{\circ}C}$ under high $Mg^{2+}$ concentration condition but melts out under low $Mg^{2+}$ concentration condition. It was also found that in the active conformation under 10 mM $MgCl_2$ condition, the unstable central G${\cdot}$U wobble pair maintains the significant base pairing up to $50{^{\circ}C}$. This study provides the information of the unique feature of the P1 duplex structure and the roll of $Mg^{2+}$ ion on the formation of the active conformation.