• The korean journal of orthodontics
• /
• v.41 no.3
• /
• pp.200-210
• /
• 2011

Objective: This study aimed at evaluating the changes in mandibular arch widths and buccolingual inclinations of mandibular posterior teeth after rapid maxillary expansion (RME). Methods: Baseline and post-expansion cone-beam computed tomographic (CBCT) images of patients who initially had bilateral posterior cross-bite and underwent RME with a banded-type expander were assessed in this study. The patients included 9 boys (mean age: $13.97{\pm}1.17$ years) and 11 girls (mean age: $13.53{\pm}2.12$ years). Images obtained 6 months after retention were available for 10 of these patients. Eighteen angular and 43 linear measurements were performed for the maxilla and mandible. The measurements were performed on frontally clipped images at the following time points; before expansion (T1), after expansion (T2), and after retention (T3). Statistical significance was assessed with paired sample $t$-test at $p$ < 0.05. Results: T1-T2 comparisons showed statistically significant post-RME increases for all measurements; similarly, T2-T1 and T3-T1 comparisons showed statistically significant changes. The maxillary linear and angular measurements showed decreases after expansion, and mandibular linear and angular measurements increased after retention. Conclusion: All mandibular arch widths increased and mandibular posterior teeth were uprighted after RME procedure.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.42 no.4
• /
• pp.446-451
• /
• 1997

A Giemsa C-banding method was used for the identification of somatic chromosomes and heterochromatic knob positions in Korean indigenous maize(Zea mays L.). Total of 10 inbred stocks were examined and their knob numbers ranged from 6 to 12. In comparison of homologous chromosomes of two stocks of Waesungri and PI 213749, arm ratios and relative length of chromosomes were different between genotypes. In comparison of arm ratios, all the homologous chromosomes except chromosome 2 were different each other. In comparison of relative length of chromosomes, that of chromosome 1 in Waesungri and PI213749 was 223.22 and 192.03 respectively. The relative length of homologous chromosomes in Waesungri were generally lager than those of PI213749. A C-banded diagram showing knob positions, arm ratios and relative length of chromosome could be used as a good tool to compare the characteristics of chromosomes of Korean indigenous maize stocks.

• Economic and Environmental Geology
• /
• v.19 no.2
• /
• pp.133-146
• /
• 1986

Primary uraninite and secondary uranium minerals such as torbernite, metatorbernite, tyuyamunite, metatyuyamunite, autunite and metaautunite have been identified from various types of uranium ores. Uranium minerals occur as accessory minerals in both the primary and secondary ores. Low·grade uranium ores consist of various kinds of primary and secondary minerals. Major constituent minerals of primary uranium ores are graphite. quartz. Ba-feldspar and sericite/muscovite, and accessories are calcite, chlorite, fluorapatite, barite, diopside, sphene, rutile, biotite, laumontite, heulandite, pyrite, sphalerite and chalcopyrite, and secondary minerals consist of kaolinite, gypsum and goethite. Uraninite grains occur as microscopic very fine-grained anhedral to euhedral disseminated particles in the graphitic matrix, showing well·stratified or zonal distribution of uranium on auto-radiographs of low-grade uranium ores. Some uraninite grains are closely associated with very fine-grained pyrite aggregates, showing an elliptical form parallel to the schistosity. Some uraninite grains include extremely fine-grained pyrite particle. Sphalerite and pyrite are often associated with uraninite in graphite-fluorapatite nodule. The size of uraninite is $2{\mu}m$ to $20{\mu}m$ in diameter. Low-grade uranium ores are classified into 5 types on the basis of geometrical pattern of mineralization. They are massive, banded, nodular, quartz or sulfide veinlet-rich and cavity filling types. Well-developed alternation of uranium-rich and uranium-poor layers, concentric distribution of uranium in graphite-fluorapatite nodule and geopetal fabrics due to the load cast of the nodule suggest that the uranium was originally deposited syngenetically. Uraninite crystals might have been formed from organo-uranium complex during diagenesis and recrystallized by metamorphism. Secondary uranium minerals such as torbernite, tyuyamunite and autunite have been formed by supergene leaching of primary ores and subsequent crystallization in cavities.

• Economic and Environmental Geology
• /
• v.3 no.3
• /
• pp.169-176
• /
• 1970

Kubong Gold Mine is located in Kuryongri, Sayang-myun, Chungyang-gun, Choongchung-Namdo.(latitude $36^{\circ}24^{\prime}N$. longitude $126^{\circ}45^{\prime}30^{{\prime}{\prime}}E$) The mine was begun to work soon after the inhabitants of this village had accidently discovered the outcrops in April 1908. It is one of the largest gold mines in Korea which produces 4,500 tons of crude ore a month. The geology in the area consists of granitic gneiss, banded gneiss, augen-gneiss, mica schist, limesilicate of Pre-Cambrian series and sedimentary rocks(sandstones & conglomerates) of Daedong series. Basic dikes intrude the former formations. The country rock of the ore deposit is a group of the metamorphic rocks mentioned above. Gold-silver bearing quartz vein contains small amounts of pyrite, chalcopyrite, arsenopyrite, galena and sphalerite in which gold and silver occur as native state. The vein strikes $N30^{\circ}{\sim}60^{\circ}E$ and dips $20^{\circ}{\sim}50^{\circ}S$ and the average width of the vein is estimated 1 to 1.5m. Average grade of ore is Au:6~8gr/t and Ag:5~6gr/t. The ore shoot continues from the outcrop to the depth of -1760ML with dip of $20{\sim}25^{\circ}$ and strike extension reaches to 400m at the depth of -1440 ML and to more or less 200m at below. Highgrade of ore vein was found at the lowest level of the ore shoot at the time of recent field survey at the end of August 1970. Its average grade was estimated as Au:20gr/t and its width 1~2.5M in average. A series of futher prospecting for other new ore shoot or parallel veins are urgent and crosscut prospecting along the horizontal level is strongly recommended.

• Geophysics and Geophysical Exploration
• /
• v.2 no.1
• /
• pp.1-7
• /
• 1999

We investigated the weathering characteristics of On-Yang gneiss by means of geological survey and Ground Penetrating Radar(GPR). The results of geological survey and boring show the two sets of vertical joint and horizontal joint developed by foliation which is composed of salic and melanic layers. GPR section evidently shows foliation direction and differential weathering due to discontinuity and mineral composition of metamorphic rock. The GPR section for instantaneous phase attribute based on complex trace analysis evidently shows continuity and foliation direction of metamorphic rock. The strong reflection amplitude which is derived from the banded structure of weathered rock can be incorrectly interpreted as a reflection of bedrock. The depth of rock basement should be estimated from the overall exploration result such as boring, seismic method, and electrical resistivity method.

• Journal of Life Science
• /
• v.8 no.1
• /
• pp.60-66
• /
• 1998

The mototic and meiotic chromosomal characteristics of ICR mice were investigated with G-and C-banding techniques. For the puposes, the chromosomal preparations were made with the modified air-drying method of Imal et al. Chromosomal analysis using testis could be observed mitotic as well as meitotic chromosomal behaviors, and the centromeric regions of all chromosomes including X chromosome were strongly stained in C-banded preparations. Nineteen autosomal bivalents and a single uniequal terminally associated X-Y bivalent in normal cells were observed during the late prophase and the metaphase of the meiosis I. The mean frequencies of previously dissociated X-Y chromosomes in the primary apermatocytes of the control group were 7.45%, but the frequencies of X-Y dissociation in the alkylating agents-treated group were about 3-4 times higher than that in the control group. Application of C-banding in meiotic stages could be certainly distinguish between vibalent type and univalents type of sex chromosomes.

• Journal of Korean Society of Steel Construction
• /
• v.28 no.3
• /
• pp.173-183
• /
• 2016

Various material characteristics of HSA800 steel were examined and a quantitative criteria about the homogeneity of the strength was proposed. Whether HSA800 steel is satisfied the criteria for homogeneity of the strength or not was also examined. From the test results, the material characteristics of 1/4 point from the extreme fiber in the Z-direction satisfied the KS requirements. The excellent directional properties and impact resistance at low temperatures were also showed from the test results. HSA800 steel satisfied the criteria of homogeneity for the strength of the steel. However, it showed that some structures were banded together at 2/4 point from extreme fiber in the Z-direction from the microscopic tests and attention is needed to be paid in that point.

• The Journal of the Petrological Society of Korea
• /
• v.7 no.3
• /
• pp.147-160
• /
• 1998

The Samrangjin Caldera, a trapdoor-type, formed by the voluminous eruption of the silicic ash-flows of the Samrangjin Tuff which is above 630m thick at the northern inside of the caldera and thinnerly 80m at the southern inside. The caldera volcanism eviscerated the magma chamber by a series of explosive eruptions during which silicic magma was ejected to form the Samrangjin Tuff. The explosive eruptions began with phreatoplinian eruption, progressed through small plinian eruption and transmitted with ash-flow eruption. During the ash-flow eruption, contemporaneous collapse of the roof of the chamber resulted in the formation of the Samrangjin caldera, a subcircular depression subsiding above 550m deep. During postcaldera volcanism after the collapse, flow-banded rhyolite was emplaced as cental plug along the central vent and ring dikes along the caldera margins. Subsequently rhyodacite porphyry and dacite porphyry were emplaced along the inner side of the ring dike. After their emplacement, residual magma was emplaced as a hornblende biotite granite stock into the southwestern caldera margin. In the northeastern part, the eastern dikes were cut final intrusions of granodioritic to granitic composition along the fault zone of $^{\circ}$W trend.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.6 no.8
• /
• pp.1358-1364
• /
• 2002

Presently, Multimedia data are increasing suddenly in broadcasting and internet fields. For retrieval of still images in multimedia database, content-based image retrieval system is implemented in this paper that user can retrieve similar objects from image database after choosing a wanted query region of object. As to extract color features from query image, we transform color to HSV with proposed method that similarity is obtained it through histogram intersection with database images after making histogram. Also, query image is transformed to gray image and induced to wavelet transformation by which spatial gray distribution and texture features are extracted using banded autocorrelogram and GLCM before having similarity values. And final similarity values is determined by adding two similarity values. In that, weight value is applied to each similarity value. We make up for defects by taking color image features but also gray image features from query image. Elevations of recall and precision are verified in experiment results.

• Journal of Life Science
• /
• v.12 no.5
• /
• pp.605-609
• /
• 2002

None of the numerous published canine idiograms and karyotypes has yet been generally accepted as a standard one because the dog has 76 acrocentric autosomes of similar size and shape. To establish canine banded karyotype from the 22nd chromosome to the 37th chromosome, we analyzed canine chromosomes by GTG, high resolution, and NOR-banding techniques. The GTG and high resolution banding patterns of canine chromosomes corresponded to other reports described previously except for a few chromosomes. While other researchers observed 12 bands, we observed 7 bands in the banding patterns of chromosome 24, 34 and 37. On the other hand, the banding patterns by NOR-banding technique showed that three pairs of autosomes have nucleolus organizer regions at the terminal ends of their long arm, and the Y chromosome has it in its short arm terminal. However, the X chromosome has no nucleolus organizer like other mammals.