• The Journal of Korean Academy of Prosthodontics
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• v.50 no.2
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• pp.92-98
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• 2012

Purpose: The aim of this study was to evaluate the effects of different abutment materials on abutment screw loosening and settling-down effect in conical connection type implant system. Materials and methods: Three types of abutment, cementation, gold UCLA, and metal UCLA abutment were used. Two UCLA groups were fabricated in a similar pattern to cementation abutment. Type III gold alloy and Nickel-Chromium alloy was used for casting gold UCLA abutment and metal UCLA abutment, respectively. Fixture and abutment were tightened to 30 Ncm by using digital torque controller and re-tightening was conducted with same force after 10 minutes. Digital torque gauge was used to measure loosening torque and fixture/abutment length was measured by digital micrometer. Dynamic loads between 25 N and 250 N were applied with $0^{\circ}$ angle to the abutment axis. After loading, fixture/abutment length was re-measured and amount of settlement was calculated. Loosening torque value was also measured for comparison Results: All three groups showed significant differences of length when comparing before and after loading, but there was no significant difference of settling amount in all groups. Loosening torque values were significantly decreased when comparing before and after loading in all groups($P$<.05). However, there was no significant difference in loss of loosening torque values when compared to groups. Conclusion: In internal conical connection type implants, dynamic load affected on settlement and loosening torque of implant, but there was no differences between abutments materials. Likewise gold UCLA abutment, metal UCLA abutment might be able to withstand functional load.

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.215-228
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• 1977

In order to provide good germplasm for developing good corn hybrids, a total of 948 Korean indigenous corn lines were collected from various parts of country and major morphological characterstics of ears were investigated. The results obtained were as follows; 1) Ear Type; From the east-north mountaionus region where more than 80% of total corn production is practiced, cylinder (type I) or similar types to cylinder corn were collected, and from the southern plain region, where rather small scales of corn is grown, cone type (type IV) or similar types to cone were prevalent. 2) Kernel color; In the ear colors of all the indigenous corn lines collected from ten regions, ears with mono color were 54.4%, ears with two color mixed were 39.0% and ears with three or more color mixed were 6.6%. In northern mountainous region, region A and region I, ear color was mostly white or white plus other colors, while in other regions ear color was yellow or yellow plus other colors. 3) Denting; Dent type was only 4.3% of Korean indigenous corn lines collected, and others were flint type. Dent type was collected from northern regions, where foreign corn varieties were introduced and grown. 4) Ear row number; Ear row numbers of indigenous corn lines collected were 12 to 16. There was no significant differences among the ear row numbers in a ear ciassified by regions. However, it was observed that ear row number was closely related to kernel size. For instance, the ears with 24 ear-rows were the smallest in kernel size. 5) Quality of starch; 70.9% of the indigenous corn lines collected were kernels with hard starch. Corn with soft starch was 26.0% and medium type was 3.1%. In region A and region I, where lot of corn is grown, corn with hard starch was more frequently collected. 6) Pop corn and waxy corn; In all the indigenous corn lines collected, popcorn was distributed uniformly through the regions except region I, and waxy corn was found more in the northern mountainous region. 7) Ear length; The mean ear length of indigenous corn lines collected was 13cm. In region A and region I ear length was larger than that in other regions. 8) Ear diameter; The mean ear diameter of indigenous corn lines collected was 3.3cm. In region A and region I ear diameter was larger than that in other regions. 9) Kernel length, kernel width and kernel thickness; The mean kernel length, kernel width and kernel thickness of indigenous corn lines collected were 0.82cm, 0.42cm, and 0.78cm, respectively. The kernel size in the region A and region I was larger than that in other regions. 10) Ear weight; The mean ear weight of indigenous corn lines collected was 58.04gr. Ear weight was remarkably heavier in region A and region I. The heaviest ear weighed 330gr, and the lightest ear weighed 5 gr. 11) Kernel weight of a ear and 100 kernel weight; Kernel weight of a ear and 100 kernel of indigenous corn lines collected were 47.07gr and 15.07gr, respectively. Kernel weights and 100 kernel weights were much heavier in region A and region I than other regions.

• Journal of Yeungnam Medical Science
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• v.21 no.1
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• pp.40-50
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• 2004

Background: This study was conducted to analyze the height and width of the pedicle of the upper and lower levels on the concave and the convex sides. In addition, we checked for the appropriate pedicle screw size which could be screwed in without complications. Materials and Methods: Taking a simple AP radiography in a standing position, 99 vertebrae on the major curve with the possibility of 3-D reconstruction were analyzed after checking the CT in a supine position of 22 idiopathic scoliosis. We measured Cobb's angle from a simple radiograph, and measured the size of the isthmus by the Inner Space 3-D Editor after 3-D reconstruction with the Inner Space 3-D program in the DICOM file transformed from CT image. We then analyzed the size of pedicles of the upper and lower levels on the concave and the convex sides by measuring the height and width of the pedicle. Results: All pedicles on the concave side were smaller than those on the convex side. Their size increased as the measurement moved from the upper to lower vertebra, except for the upper thoracic vertebra. When the width of the pedicle through 3-D reconstruction was compared with the narrowest width of the pedicle measured by using CT, the width of the pedicles through 3-D reconstruction was statistically smaller (P<0.01). Most of the pedicles were tear-drop or kidney shaped rather than cylindrical. Conclusion: These results suggest that the use of the coronal plane through 3-D reconstruction would be necessary for an accurate measurement of the size of the pedicle. It is important to pay careful attention to the screw size and the screwing method considering the pedicle shape through 3-D reconstruction.

• Applied Microscopy
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• v.32 no.1
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• pp.57-66
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• 2002

The structures of sucker of two Cobiidae; Common freshwater goby and Triden goby were observed by light and electron microscopy. Scanning electron microscopy revealed the characteristic narrow ridges and grooves on the apical portion of sucker of Common freshwater goby, and hexagonal structures similar to a honeycomb representing the intercellular junctional area on the middle and basal portions. Some ridges were present on the epithelial surface on the middle and basal portions. The openings of several mucus-secreting cells were present between main epithelial cells. Light and transmission electron microscopy revealed the core of the fin; soft rays with a surrounding dense collagen fiber layer. Some loosely arranged fibers (collagen fiber) radiated toward the surface epithelium. The surface epithelium was cuboidal or columnar in shape. Scanning electron microscopy revealed the coiled irregular ridges and grooves, which was less developed and had sparser distribution than in Common freshwater goby, on the apical portion of sucker of Triden goby. The middle and basal portions had honeycomb structures as in Common freshwater goby. Fewer mucoussecreting cells were present. Light and transmission electron microscopy showed the core of soft rays, dense collagen fiber layer, however, the radiating fibers observed in the Common freshwater goby was rarely present. The sucker was thinner because the epithelium is squamous or polygonal in shape and rare presence of the radiating fibers.

• Animal Systematics, Evolution and Diversity
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• v.20 no.2
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• pp.201-214
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• 2004

Some actiniarians were collected from the coasts of Jejudo and Baekdo Islands in Korean waters from 1971 to 2004. They are identified into three species within three families, which are newly recorded to Korean actiniarian fauna: Halcampella maxima Hertwig, 1888 within the tribe Athenaria, and also Aulactinia coccinea (Verrill, 1866) and Stichodactyla tapetum (Ehrenberg, 1834) within the tribe Thenaria. They are described in detail with figures and tables together with the distribution and size of cnidae. In preserved specimens, mature oocytes of H. maxima were observed in winter. Also oocytes and sperm sacs of S. tapetum were surveyed at separate individuals in summer. The unique feature of A. coccinea is a body wall with simple adhesive verrucae extended from margin to limbus in longitudinal rows. In the genus Stichodactyla, the smallest species, S. tapetum is distinguished from S. haddoni by short bulbous tentacles, less than 1.0 mm long, densely packed on the oral disc and also conical marginal ones, 1.5-2.0 mm long. As a result of this study, the Korean actiniarian fauna consists of four athenarian and 23 thenarian species in suborder Nynantheae

• Journal of the Korean GEO-environmental Society
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• v.5 no.4
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• pp.33-45
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• 2004

In the present study, more systematic laboratory model tests under various conditions are carried out to investigate load-sharing characteristics among the granular pile and adjacent soils and bearing capacity characteristics with different pile lengths. Further to evaluate effects of both a loading area and a spacing of pile installation on the bearing capacity and bearing capacity characteristics of each pile in group, model test results are also analyzed for the purpose of an efficient design of granular compaction piles. From the analysis of the model test results, it is found that the ultimate capacity of granular compaction group piles increases with a decrease in the installation distance among granular piles. It is also found that the dominant failure mode of the granular compaction piles is bulging failure. It is further realized that the length of a granular pile could not significantly affect on the ultimate granular pile capacity.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.4
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• pp.646-650
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• 2007

The purpose of this study was to evaluate the prevalence of mesiodens at pediatric dental clinic in Anyang, Kyeong Gi-Do. From retrospective reviews of all patients who visited Kizwell pediatric dental clinic from 2003.4-2006.4, 241 patients (289 mesiodens) who were shown to have mesiodentes were examed by a periapical radiograph and a panoramic radiograph. The incidence of mesiodens was 3.42% and the ratio of male/female (184/57) was 3.2:1. The number of supernumerary teeth was one in 193 cases (80%), two in 48 cases (20%). The mesiodens was placed at left side more frequently and the most common shape was conical type (208, 78%). Of 289 mesiodens, the direction of the crown of the mesiodens was inverted in 156 (54%), in a normal direction in 104 (36%), in a horizontal direction with regard to the tooth axis in 29 (10%). Early diagnosis of the mesiodens allow the most appropriate treatment, often reducing the extent of surgery, orthodontic treatment and possible complications.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.185-191
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• 2014

Corythucha marmorata (Uhler) belonging to the family Tingidae (Hemiptera) has been reported in Korea. In 2013, surveys were conducted to study its morphological characteristics, geographical distribution, and host plants. The adult is brown white and 2.77-3.28 mm in length, and the mature nymph is yellowish brown. Heavily infested trees appear yellowish white because they are fed on by the nymphs on the under surface of host plants. C. marmorata were found between early June and late October, and their numbers peaked in early July to late August. In 2013, the occurrence of C. marmorata was confirmed in 27 cities and counties nationwide, and 8 families and 24 species of host plants were identified. C. marmorata feeds on the following major host plants: Conyza canadensis, Aster pilosus, Helianthus annuus, Artemisia princeps, Rudbeckia bicolor, and Solanum melongena.

• The Journal of the Acoustical Society of Korea
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• v.35 no.5
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• pp.403-409
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• 2016

Traditional towed line arrays using omni-directional sensor suffer from the well known port-starboard ambiguity, because the direction of arrival is determined by conic angle. The operational method and structure of the sensor arrays method have been proposed to solve this problem. Recently, a lot of research relating to the acoustic vector sensor are studied. In this paper, we study port-starboard discrimination for roll of acoustic vector sensor array. With one omni-directional sensor and three orthogonally-placed directional sensors, an acoustic vector sensor is able to measure both the acoustic pressure and the three directional velocities at the point of the sensor. The wrong axis due to the roll at directional sensors can degrade performance of beamforming. We investigate port-starboard discrimination for roll of sensor array and confirm the validity of performance of beamforming with compensated the roll.

• Korean Journal of Plant Resources
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• v.10 no.2
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• pp.135-139
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• 1997

A new Sikbangpoong(Peucedanum japonicum Thunberg) variety, 'Sikbangpoog 1', was developed through a pure line selection at the Kyougpuk Provincial RDA during the period of 1990 to 1995. The variety was characterized to have higher stem height, leaf number and seed production, and larger root diameter compared with the check variety of Bonghwa Sikbangpoong but plant height of 'Siknagpoong 1' was similar to that of the check variety and it was also more tolerant to water and heat stress. Root color of 'Sikbangpoong 1' was yellowish brown and root shape of the variety was straight and conical. The root yields of Sikbangpoong 1 in yield trial, regional adaptation trial and farmer's field trial were always 10-28% higher than those of the check variety.