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The prosthetic approach and principle for an collapsed VDO ; A clinical case of pseudo Class III patient (저위교합환자의 보철적 접근법과 이론 : Pseudo Class III 교합환자 증례)

  • Kwon, Kung-Rock;Choi, Dae-Gyun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.20 no.2
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    • pp.121-134
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    • 2004
  • This article describes a clinical protocol for the conventional rehabilitation of patient diagnosed with partial anodontia. A combined dental therapy approach was used and included endodontic therapy and root capping on the maxillary central incisors, fabrication of a maxillary overdenture, and fabrication of mandibular konus overdenture supported by 3 konus abutments. Within this protocol, tooth-supported overdenture prostheses are used for 2 purposes: first, to obtain the most rigid retention and function at an established maxillary-mandibular relationship; and second, to continuously maintain function and esthetic appearance applying immediate dentures after teeth extraction. The idea behind this protocol and its associated clinical procedures is presented along with a discussion compared with implant therapy. In the case introduced, and after 7 years of observation, the therapy can be seen as a success. We increased the occlusal vertical height in this case, but it would be more appropriate to see this as recovering the occlusal vertical height that was lost. The process of increasing the occlusal vertical height, that is restoration of the face, modification of the extrinsic occlusion of the incisors, and retraction of the mandible is very difficult and important. Ultimately, class III malocclusion is fixed, adequate occlusal vertical height is gained, and the retracted posterior anodontial portion is restored by prosthodontic dentures based on the rigid support theory. The result of the therapy done on the later-achieved malocclusion with partial anodontia on the posterior portion must consider the following in order to maintain the safety of the esthetics of the tooth and face for a period of time: 1) occlusal restoration with an ideal occlusal vertical height, 2) allowance of the final occlusion induced by the functional relationship of the upper and lower jaw, 3)final occlusion functionally induced by the lip competence limit.

Conical Slope Stability of Tertiary Basalt Based on the Geological Cross-Sections (지질횡단면을 활용한 원추형 현무암 비탈면 안정성)

  • Myeong-Hyeok Ihm;Sung-Pil Hwang;Byung-Suk Park;Jun-Sang An;Woo-Seok Kim
    • The Journal of Engineering Geology
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    • v.34 no.3
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    • pp.447-457
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    • 2024
  • This study investigated a cut-slope surface containing Tertiary faults, representing a conical-shaped slope with strike varying from N44°E to NS, N50°W, and finally N70°E. The slope consists mainly of basalt, with discontinuities in the slope including faults, fault zones, fracture zones, shear joints, and extension joints. The type and scale of failure vary with the strike of the slope and the strikes of discontinuities, with plane and wedge failure predominating. Based on face-mapping data, SMR (slope mass rating), rock physical and mechanical properties, analysis of stereonet projections and geological cross-sections, and critical equilibrium analysis, optimal slope stability determination was found to involve the countermeasure method, the slope gradient relief method, the green soil surface treatment method, and a fall prevention measure. After application of the countermeasure method, both dry and wet slope conditions exceeded allowable safety factors. It is expected that the preparation of geological cross-sections of various representative sections perpendicular to the surface of the slope, and the application of corresponding countermeasure methods, will be reasonable tools for three-dimensional analysis of slope stability. If the strike of the slope varies widely, it is necessary to prepare geological cross-sections, and the section used for critical equilibrium analysis must be established as the basic section.

Case Studies on Applications of Convergence Measurement Systems at the Stages of Tunnel Construction and Maintenance (터널 시공 및 유지관리 단계 내공변위 계측시스템 적용사례 연구)

  • Lee, Dae-Hyuck;Han, Il-Yeong;Kim, Ki-Sun;Jin, Suk-Woo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.2 no.3
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    • pp.59-69
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    • 2000
  • Three-dimensional total station system which integrated the instrument with Target Pin and TEMS 3D software developed by SKEC R&D center was applied to a tunnel excavation for monitoring of convergence and crown settlement. The efficiency of the system was proved as the result in the aspects of exact monitoring and prediction of rock conditions ahead of the face. To monitor the behavior of tunnel lining at the maintenance stage, DOCS system was applied to the subway tunnel section. Such many effects as the vibration of sensors, verification of the system efficiency, the effect of test trains operation, the variation of temperature and the effect of high voltage was checked. Thus the management scheme for tunnel maintenance was laid out as a proposal.

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Compression characteristics of filling gangue and simulation of mining with gangue backfilling: An experimental investigation

  • Wang, Changxiang;Shen, Baotang;Chen, Juntao;Tong, Weixin;Jiang, Zhe;Liu, Yin;Li, Yangyang
    • Geomechanics and Engineering
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    • v.20 no.6
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    • pp.485-495
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    • 2020
  • Based on the movement characteristics of overlying strata with gangue backfilling, the compression test of gangue is designed. The deformation characterristics of gangue is obtained based on the different Talbot index. The deformation has a logarithmic growth trend, including sharp deformation stage, linear deformation stage, rheological stage, and the resistance to deformation changes in different stages. The more advantageous Talbot gradation index is obtained to control the surface subsidence. On the basis of similarity simulation test with gangue backfilling, the characteristics of roof failure and the evolution of the supporting force are analyzed. In the early stage of gangue backfilling, beam structure damage directly occurs at the roof, and the layer is separated from the overlying rock. As the working face advances, the crack arch of the basic roof is generated, and the separation layer is closed. Due to the supporting effect of filling gangue, the stress concentration in gangue backfilling stope is relatively mild. Based on the equivalent mining height model of gangue backfilling stope, the relationship between full ratio and mining height is obtained. It is necessary to ensure that the gradation of filling gangue meets the Talbot distribution of n=0.5, and the full ratio meets the protection grade requirements of surface buildings.

Earthquake performance evaluation of three-dimensional roller compacted concrete dams

  • Kartal, Murat Emre;Karabulut, Muhammet
    • Earthquakes and Structures
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    • v.14 no.2
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    • pp.167-178
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    • 2018
  • A roller compacted concrete (RCC) dam should be analyzed under seismic ground motions for different conditions such as empty reservoir and full reservoir conditions. This study presents three-dimensional earthquake response and performance of a RCC dam considering materially non-linearity. For this purpose, Cine RCC dam constructed in Aydın, Turkey, is selected in applications. The three-dimensional finite element model of Cine RCC dam is obtained using ANSYS software. The Drucker-Prager material model is considered in the materially nonlinear time history analyses for concrete and foundation rock. Furthermore, hydrodynamic effect was investigated in linear and non-linear dynamic analyses. Researchers observe that how the tensile and compressive stresses change by hydrodynamic pressure effect. The hydrodynamic pressure of the reservoir water is modeled with the fluid finite elements based on the Lagrangian approach. In this study, dam body and foundation are modeled with welded contact. The displacements and principle stress components obtained from the linear and non-linear analyses with and without reservoir water are compared each other. Principle stresses during earthquake were obtained at the most critical point in the upstream face of dam body. Besides, the change of displacements and stresses by crest length were investigated. Moreover demand-capacity ratio criteria were also studied under linear dynamic and nonlinear analysis. Earthquake performance analyses were carried out for different cases and evaluated. According to linear and nonlinear analysis, hydrodynamic water effect is obvious in full reservoir situation. On the other hand, higher tensile stresses were observed in linear analyses and then non-linear analyses were performed and compared with each other.

Geo-tourism : A Practical Application to Mt. Apsan in Daegu (지오 투어리즘(Geo-tourism)을 위한 대구 앞산 활용방안)

  • Jeon, Young-Gweon
    • Journal of the Korean association of regional geographers
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    • v.11 no.6
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    • pp.517-529
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    • 2005
  • Mt. Apsan is well known to be one of the most popular tourist sites around Daegu. Annually, more than 16 million persons visit Mt. Apsan. Although, in the mountain there are varieties of geomorphic and geological resources, there has been less concern to utilize the resources for geo-tourism. For example, there are about 10 valleys within Mt. Apsan and various landforms are scattered around the valleys. In this context, this study, based on field surveys centering around Gosangol valley, Anjiranggol valley and Dalbigol valley, focuses on exploring ways towards developing Mt. Apsan as an example geo-tourist site. The main findings are as follows: 1) The main landforms of Mt. Apsan include river cliff, cavern, free face, mud crack, ripple mark, fold, sheeting joint, talus, alluvial fan, pot hole, fault line, gnamma, columnar joint and metamorphic rock. 2) The guide notes on the landforms are developed. 3) In order to raise a learning effect of visitors on geomorphic resources, 9 nature trails are designed according to valleys and the length of visitor's stay.

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Overseas Design Introduction of Road Rehabilitation Project in Keshim~Faizabad, Afghanistan (아프가니스탄 케심-파이자베드간 도로복구사업 해외설계 사례)

  • Jeong, Dong-Ho;Kim, Woo-Sun;Kim, Gee-Baek;Jeong, Won-Joon;Lee, Seung-Woo
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.569-580
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    • 2008
  • If slope height was more than 20 meters, we conducted an analysis of stereographic projection and limit equilibrium at this slope. We proposed reduction of slope face angle and reinforcement of rock bolt depending on analysis. Blasting design : Standard pattern based on result of local test blasting was made for blasting design. Vibration criterion was set for less than 3.0mm/s because of outworn buildings and inhabitants opinions. Production blasting and Controlled blasting has been done as Construction standard pattern. After Vibration Monitoring has been done, so that we can control of complement. "Bidding Document" and AASHTO 2001 "A Policy on Geometric Design of Highways and Streets" were so for design criteria of earthwork but they were different actual design criteria and left something to be desired in Afghanistan. Therefore, although "Bidding Document" and "AASHTO 2001" were basic design criteria, domestic design criteria was reflected in this design criteria for complement by discussion with supervisor. Drainage design : For stability ratio, ditch of arch block and stonework was designed by rainfall data for the 13 years and discussion with supervisor. Pavement was designed as flexible pavement. Because these days in Afghanistan postwar repair works, especially urgent repairing of roads and newly making of roads, are very highly in progress, I think that Afghanistan is the region about which our construction technical experts should have great concerns.

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Case Study on the Tunnel Collapses during the Construction and Application of Geotechnical Investigation (터널 시공 중 지반 관련 사고 사례의 원인 분석과 지반 조사 결과의 활용에 관한 검토)

  • Park, Nam-Seo;Lee, Chi-Mun;Gang, Sang-Ho
    • Proceedings of the Korean Geotechical Society Conference
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    • 1998.04a
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    • pp.47-60
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    • 1998
  • It is considered in this paper that the main causes of tunnel collapse during the construction were the insufficiency of data of geotechnical investigations, or their limits due to special ground condition such as its heterogeneity and anisotropy It is thought that safety of ground can be affected by the geological conditions such as presences of discontinuities in good intact rocks, and considered to be necessary that awareness of the conditions of discontinuities in advance is important to apply adequate reinforcement measures. It is also shown that a serious accident had occurred because of the unawareness of the permeable alluvial deposits at the top of the tunnel. And it is shown that the example of application of the results of geotechnical investigation such as face-mapping, pilot boring etc. during tunnel construction, and a serious deformation of tunnel under special geological condition. Therefore, it is strongly recommended to perform an adequate geotechnical investigation to confirm the geotechnical conditons of ground before design, and supplimentary investigation is also needed depending on conditions for safe and econonic construction.

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Why is Seogwipo Warm in Winter? The wind from Jeju City to Seogwipo-The Wind from Seogwipo to Jeju City (서귀포는 겨울철에 왜 따뜻할까? 제귀지풍과 귀제지풍)

  • Sung kook Lee;Moon Ho Lee;Jeong Su Kim
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.4
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    • pp.121-125
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    • 2023
  • In winter, Jeju's Seogwipo and Jungmun areas are 2~3℃ warmer than Jeju City. The reason is that when the north wind over Halla Mountain crosses Baengnokdam of Halla Mountain and passes the 300m long and 260m vertical rock face of Donnaeko at an altitude of 1600m above sea level, the cold air turns into warm air through adiabatic compression, and the warmth rides on Donnaeko and flies to Seogwipo and Jungmun. Conversely, the south wind that rises over the sea in Seogwipo in the summer passes over Hallasan Mountain and passes 99 valleys before turning into a muggy, humid climate, making Jeju hot. In other words, it is because of The wind from Jeju City to Seogwipo-The Wind from Seogwipo to Jeju City.

The Study on the Debris Slope Landform in the Southern Taebaek Mountains (태백산맥 남부산지의 암설사면지형)

  • Jeon, Young-Gweon
    • Journal of the Korean Geographical Society
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    • v.28 no.2
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    • pp.77-98
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    • 1993
  • The intent of this study is to analyze the characteristics of distribution, patter, and deposits of the exposed debris slope landform by aerial photography interpretation, measure-ment on the topographical maps and field surveys in the southern part Taebaek mountains. It also aims to research the arrangement types of mountain slope and the landform development of debris slopes in this area. In conclusion, main observations can be summed up as follows. 1. The distribution characteristics 1)From the viewpoint of bedrocks, the distribution density of talus is high in case of the bedrock with high density of joints, sheeting structures and hard rocks, but that of the block stream is high in case of intrusive rocks with the talus line. 2)From the viewpoint of bedrocks, the distribution density of talus is high in case of the bedrock with high density of joints, sheeting structures and hard rocks, but that of the block stream is high in case of inrtusive rocks with the talus line. 2) From the viewpoint of distribution altitude, talus is mainly distributed in the 301~500 meters part above the sea level, while the block stream is distributed in the 101~300 meters part. 3) From the viewpoint of slope oriention, the distribution density of talus on the slope facing the south(S, SE, SW) is a little higher than that of talus on the slope facing the north(N, NE, NW). 2. The Pattern Characteristics 1) The tongue-shaped type among the four types is the most in number. 2) The average length of talus slope is 99 meters, especially that of talus composed of hornfels or granodiorite is longer. Foth the former is easy to make free face; the latter is easdy to produce round stones. The average length of block stream slope is 145 meters, the longest of all is one km(granodiorite). 3) The gradient of talus slope is 20~45${^\circ}$, most of them 26-30${^\croc}$; but talus composed of intrusive rocks is gentle. 4) The slope pattern of talus shows concave slope, which means readjustment of constituent debris. Some of the block stream slope patterns show concave slope at the upper slope and the lower slope, but convex slope at the middle slope; others have uneven slope. 3. The deposit characteristics 1) The average length of constituent debris is 48~172 centimeters in diameter, the sorting of debris is not bad without matrix. That of block stream is longer than that of talus; this difference of debris average diameter is funda-mentally caused by joint space of bedrocks. 2) The shape of constituent debris in talus is mainly angular, but that of the debris composed of intrusive rocks is sub-angular. The shape of constituent debris in block stream is mainly sub-roundl. 3) IN case dof talus, debris diameter is generally increasing with downward slope, but some of them are disordered and the debris diameter of the sides are larger than that of the middle part on a landform surface. In block stream, debris diameter variation is perpendicularly disordered, and the debris diameter of the middle part is generally larger than that of the sides on a landform surface. 4)The long axis orientation of debris is a not bad at the lower part of the slope in talus (only 2 of 6 talus). In block stream(2 of 3), one is good in sorting; another is not bad. The researcher thinks that the latter was caused by the collapse of constituent debris. 5) Most debris were weathered and some are secondly weathered in situ, but talus composed of fresh debris is developing. 4. The landform development of debris slopes and the arrangement types of the mountain slope 1) The formation and development period of talus is divided into two periods. The first period is formation period of talus9the last glacial period), the second period is adjustment period(postglacial age). And that of block stream is divided into three periods: the first period is production period of blocks(tertiary, interglacial period), the second formation period of block stream(the last glacial period), and the third adjustment period of block stream(postglacialage). 2) The arrangement types of mountain slope are divided into six types in this research area, which are as follows. Type I; high level convex slope-free face-talus-block stream-alluvial surface Type II: high level convex slope-free face-talus-alluvial surface Type III: free face-talus-block stream-all-uvial surface Type IV: free face-talus-alluval surface Type V: talus-alluval surface Type VI: block stream-alluvial surface Particularly, type IV id\s basic type of all; others are modified ones.

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