• The Journal of Korean Academy of Prosthodontics
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• v.42 no.1
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• pp.73-82
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• 2004

Statment of problem : Little in known about the importance of selection of various double crowns as retainer in determining the outcome of treatment with double crown retained removable partial denture. Purpose : To obtain information about the effects and the results of this treatment modality. Material and methods : This study describes 61 double crown retained removable partial dentures worn by 51 patients from Samsung Medical Center, Seoul a time ranging between 6 and 48 months and evaluate occlusal contacts on the denture teeth, denture movement, incidence of denture relining, denture retention, fracture of dentures and abutments, hygiene, residual ridge inflammatory changes, number of lost abutment,. interruption of denture use. Results : One tenth of all the restorations were relined. Restorations in 21 arches fractured repeatedly for various reasons . There was no apparent interrelationship between fractures and the five groups. Conclusion : Good prognoses of removable partial dentures were shown in all groups(Kennedy Classes I, II, III, combination and few remaining abutment).

• The korean journal of orthodontics
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• v.52 no.3
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• pp.236-245
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• 2022

New digital technologies, many involving three-dimensional printing, bring benefits for clinical applications. This article reports on the clinical procedure and fabrication of a skeletally anchored mesialization appliance (Mesialslider) using computer-aided design/computer-aided manufacturing (CAD/CAM) for space closure of a congenitally missing lateral incisor in a 12-year-old female patient. The insertion of the mini-implants and appliance was performed in a single appointment. Bodily movement of the molars was achieved using the Mesialslider. Anchorage loss, such as deviation of the anterior midline or palatal tilting of the anterior teeth, was completely avoided. CAD/CAM facilitates safe and precise insertion of mini-implants. Further, mini-implants can improve patient comfort by reducing the number of office visits and eliminating the need for orthodontic bands and physical impressions.

• The korean journal of orthodontics
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• v.17 no.2
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• pp.223-248
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• 1987

The early tissue reactions in the periodontal tissues of the tension zones following the application of force (30gm) to the maxillary first molar teeth of the albino rats were studied by the light microscopy and electron microscopy The increase of periodontal fibroblasts was evident, particularly in 1 day survival period. Osteoblast differentiation and new bone formation on the alveolar bone surface were occurred from 1 day survival period. Mononuclear phagocytes occurred consistently and in relatively high number adjacent to and at some distance from blood vessel Extensive breakdown of collagen fibers was observed. The increase of the phagocytosis of collagen by the active fibroblasts was evident Also, collagen fibrils were sparse or lost near the macrophage.

• The korean journal of orthodontics
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• v.5 no.1
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• pp.11-19
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• 1975

This study was undertaken to investigate the exact values of the cephalometric standards of Hellman dental age III B groups of Korean in the reontgenocephalometry. The subjects consisted of 25 males and the same number of females with the normal occlusion and acceptable profile. Each lateral cephalometric head film was taken with the teeth in occlusion and the Focal-film distance was 300cm. Their linear and angular measurements were made directly. The following conclusions were obtained; 1) The author made the tables of standard deviation from the measured values. 2) The degree of the facial convexity of Korean children was larger than that of the white. 3) The labial inclination of the lower central incisor in male was a little greater than that in female.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.1
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• pp.58-65
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• 2005

A planetary gear trains has characteristics in compactness, power transformation ability and constant meshing. Usability is increased in applications of auto transmission and industrial gearbox. Study on optimum design of planetary gear train has been progressed on miniaturization of weight, miniaturization of planetary gear train and improvement of high strength. There are demands of study f3r the planetary gear train required long life estimation. In this work being considered life, strength, interference, contact ratio and aspect ratio, the optimum design algorithm is proposed to reduce the volume of planetary gear train with transferring the same amount of power. In the design of algerian for planetary gear train, the determination of teeth number is separated to achieve simplicity and the simulated annealing method as a global optimal technique is used far optimal design method.

• Parasites, Hosts and Diseases
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• v.21 no.1
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• pp.118-124
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• 1983

The distribution, external morphology, radula, chromosome numbers of Planorbidae snails were studied. 1. The specimens were collected at four stations in Nonsangun, Kongjugun, and Daedukgun which are located around Geum river. Three genera and three species of Planorbidae, Hippeutis cantorir Segmentina hemisphaerula and Gyraulus cenvexiusculus, were collected. H. cantori was the most abundant species among the three species. G. convexiusculus was the least abundant one. 2. Each species could be identified on the basis of its external characteristic, since the periphery of each species has a peculiar shape. H. cantori was the largest one among the three species. 3. The radula formula of each species was very similar to other species. The size of radula was proportional to the size of shell. The radula formulae of H. cantori, S. hemisphaerula, and G. convexiusculus were 29 : 1 : 29, 23 : 1 : 23, and 16 : 1 : 16 respectively. The difference of radula formula could be found in the total numbers of laternal and marginal teeth. 4. The haploid chromosome number of H. cantori was eighteen (n=18), S. hemisphaerula and G. convesiusculus were assumed to be same in their chromosome numbers (n: 18).

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.172-177
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• 2004

A planetary gear trains has characteristics in compactness, power transformation ability and constant meshing. Usability is increased in applications of auto transmission and industrial gearbox. Study on optimum design of planetary gear train has been progressed on minimization of weight, miniaturization of planetary gear train and improvement of high strength. There are demands of study for the planetary gear train required long lift estimation In this wort being considered life, strength, intereference, contact ratio and aspect ratio, the optimum design algorithm is proposed to reduce the volume of planetary gear train with transferring the same amount of power. In the design of algorithm for planetary gear train, the determination of teeth number is separated to achieve simplicity and the simulated annealing method as a global optimal technique is used for optimal design method.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1994.03a
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• pp.55-62
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• 1994

For theoretical estimate of closed-die forging pressure, upper-bound method is applied to the involute tooth profile. In the analysis, the deformation regions have been divided into several zones. A constant frictional stress has been assumed on the contacting surfaces. Utilizing the formulated velocity fields, numerical calculations have been carried out to investigate the effects of various parameters, such as module, number of teeth and friction factor, on the forging of spur gears. Very close agreement was found between the predicted values of forging load and those obtained from experimental results.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1995.03a
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• pp.41-53
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• 1995

Forging of spur gears has been investigated by means of upper-bound method. The term forging means forging of spur gears with solid cylindrical billets, hollow billets with flat punch. Kinematically admissbile velocity field for forging of spur gears has been proposed in this study. The 1/2 pitch of spur gear has been divided into seven dieformation regions, wherein, an involute curve has been introduced to represent the shape of die profile. Especially neutral surface has been introduced intor forging of hollow gears from hollow billets. By using the kinematically admissible velocity field, the powder requirements and suitable conditions for forging fo spur gears were successfully calculated with numerical method. According to the analysis , the acceptable number of teeth for forging of spur gears is from 15 to 20.

• Journal of Species Research
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• v.1 no.1
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• pp.44-55
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• 2012

A harpacticoid copepod, Sinamphiascus dominatus Mu & Gee, 2000 is re-described from the sandy bottom in off Jeju Island of Korea. The genus Sinamphiascus was established with single species, S. dominatus from the Bohai Sea, China. The main diagnostic characters of the specimen from Korea are well matched with the original description, although it has minor discrepancies including the lengths and ornamentation of setae in leg 6 of both sexes, shape of the base on furcal setae and teeth number of labrum in female. However those discrepancies are regarded to the intra-specific variations. This is the first record of genus Sinamphiascus in Korean waters.