• Journal of Korean Dental Science
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• v.17 no.2
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• pp.84-91
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• 2024

Achieving both esthetic and functional implant rehabilitation is crucial for the successful treatment of the anterior maxilla. Adequate peri-implant alveolar bone and soft tissue are essential for optimal rehabilitation of the esthetic area, and there is a direct association between the implant position and prosthetic outcomes. Immediate provisionalization may also be advantageous when combined with augmentation. This case report described the implant placement in a 25-year-old female patient who had lost her right maxillary lateral incisor (#12) due to trauma-induced avulsion. The treatment involved simultaneous grafting and collagenated, deproteinized bovine bone mineral, along with subepithelial connective tissue taken from the right maxillary tuberosity. A polyetheretherketone abutment and non-functional immediate provisionalization were performed by removing both the proximal and occlusal contacts on the composite resin crown. Clinical and radiographic evaluations revealed maintenance of stable ridge contour aspects for six months following surgical treatment. In summary, implant rehabilitation in the esthetic zone can be successful using simultaneous soft and hard tissue grafts. Moreover, soft tissue stabilization post-subepithelial connective tissue grafting can be achieved through early or immediate visualization, along with immediate implant placement.

• Journal of the Korean GEO-environmental Society
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• v.8 no.3
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• pp.27-33
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• 2007

The vertical drain method recently being used in Korea is one of the popular soft ground improvement methods, and it is divided into the sand drain method, the pack drain method, the paper drain method, and the PBD method according to the drainage. However, these methods generate the disturbed zone called the smear zone when the drainage is penetrated into the in-situ ground. The characteristics of the smear zone generated cause the problems that the coefficient of permeability decreases, and then the consolidation time in the design becomes longer than expected. Even though the coefficient of horizontal consolidation and the coefficient of permeability in the smear zone are very important design factors directly influencing the degree of consolidation, in the existing studies, these coefficients have been empirically derived by the coefficient of vertical consolidation and used for the design. However, in case that these coefficients derived by the coefficient of vertical consolidation are applied to the actual design, a loss of the duration of construction and a loss of economical efficiency can be happened because of the inaccuracy of the coefficient of horizontal consolidation and the coefficient of permeability. Hence, in this study, in order to understand such influence, the laboratory test was carried out so as to reasonably determine the coefficient of permeability and the coefficient of consolidation in diverse ground conditions. Then, the range of smear effect on clay and silt was estimated with monitoring data through the laboratory test.

• Transactions of Materials Processing
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• v.16 no.7
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• pp.530-537
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• 2007

This paper is concerned with the analysis of plastic deformation of bimetal co-extrusion process. Two sets of material combination have been adopted for analysis, i.e. combinations of Cu/Al and Fe/Al. In the first set of material combination, the selected materials are AA 1100 aluminum alloy as hard material and CDA 110 as soft one. This type of material selection is to examine the effect of hard core and soft sleeve and vice versa on the deformation pattern in terms of plastic zone and velocity discontinuity along the contact surface between construction materials. Four different cases of co-extrusion process in terms of material combination and interference bonding were simulated to investigate the effect of material arrangement between core and sleeve, and of bonding on the plastic zones and velocity discontinuity. In the other set of material combination, model materials used as core and sleeve were AA 1100 and AISI 1010, which are relatively soft and hard, respectively. Process parameters except diameter ratio of core to sleeve material such as semi-die angle, reduction in area in global sense and die comer radius have been set constant throughout the simulation to concentrate our effort on the analysis of influence of diameter ratio on deformation behavior such as deformation zone, surface expansion, exit velocity discontinuity between composite materials, and extrusion forces.

• Journal of the Korean Geotechnical Society
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• v.28 no.1
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• pp.41-53
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• 2012

As the permeability of soil adjacent to the vertical drain has a decisive effect on the rate of consolidation, the permeability of smear zone governs the rate of radial consolidation of PVD installed soft ground. In this study, a method was suggested to analyze the radial consolidation, based on consolidation characteristics of remolded clay, and was used to evaluate the consolidation of soft clay layer in Busan Newport. The suggested method provides more reliable consolidation behaviors than the conventional approach, which is based on the consolidation characteristics of undisturbed clay. The suggested method is also observed to be relatively insensitive to the uncertainty of $k_h/k_s$. The comparison between the analysis and field measurement revealed that the suggested method provided a reliable prediction on the rate of consolidation of PVD installed Busan new port clay and that an appropriate extent of smear zone was evaluated as about $3d_w$ by back analysis.

• Journal of Welding and Joining
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• v.33 no.1
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• pp.41-48
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• 2015

In this study, the effect of heat input on weld metal microstructure and the effects of dissimilar weld heat affected zone in quenched and tempered ASTM A517 on the stainless steel AISI 316L is investigated through the optimization of welding parameters. For this purpose, two welding techniques are used, tungsten-conventional gas and pulsed gas with weld wire ER 309MoL with Diameter 2.4 mm. Research showed that the grain size of the heat affected zone in pulsed welding is less compared with conventional welding; weld metal structure is fully austenitic, it has a finer structure in the pulsed method. Additionally, the growth of weld metal adjacent steel A517 is different from steel 316L. Further, investigation showed that the rate of dilution is less in the pulsed method and the impact energy is increased in each three regions of the weld metal and heat affected zones in the pulsed method; the fracture in the weld metal and heat affected zone of steel 316L is quite soft and it is semi-crispy in the heat affected zone of steel A517.

• Archives of Reconstructive Microsurgery
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• v.15 no.1
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• pp.10-16
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• 2006

We retrospectively evaluated our results of replantations of distal digital amputations and analyzed the factors deterrent to the survival of replanted digits. From January 2004 to 2005 June, we performed 101 cases of replantations following complete amputations at or distal to interphalangeal joint level. The study included 98 patients with a mean age of 35.6 years (range 1 to 63 years). Amputation level correlated to zone I (distal to the lunula)in 47 cases and zone II (lunula to distal interphalangeal joint) in 54 cases according to Yamano's classification. According to the mechanism of amputation, 24 cases (22.9%) suffered from guillotine type injury, 27 cases (27.1 %) from avulsion type injury and 50 cases (50%) from crush type injury. In all cases, a single arterial anastomosis was performed. Venous anastomosis on either volar or dorsal side was performed in 12 cases of amputation in zone II. Salvage procedure for venous drainage was performed in 98 cases. The mean duration of salvage procedures was 5.9 days (ranging from 4 to 14 days). Successful replantation was achieved in 96 cases (95.1%), which included 93.7% cases in zone I amputations and 96.3% cases in zone II amputations. A single venous anastomosis was performed in 12 cases of amputation in zone II. All of them survived completely. Among the 5 cases that failed to survive, 3 cases were related with avulsion injury in zone I. Initial mechanism of injury determines the survival rate of amputated parts as it is directly related with the status of vessels and soft tissues. Meticulous precaution during the salvage procedure may affect the overall survival rate of distal digital replantations.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.1
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• pp.35-45
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• 2016

Purpose: The present study was aimed to investigate the effect of corneal eccentricity on the axial rotation when wearing toric soft contact lenses were worn for certain time and changing the gaze directions. Methods: Toric soft contact lenses with double thin zone design applied on 85 of with-the-rule astigmatic eyes. Then, rotational direction and amount of contact lenses were measured after 15 minutes and 6 hours of lens wear. The difference was further compared and analyzed according to corneal eccentricity. Results: The rotation of toric lens showed a tendency to rotate to temporal direction in all gaze directions except temporal-upper direction in all groups of corneal eccentricity. The amount of lens rotation in the frontal gaze direction exhibited a negative correlation since the amount was decreased with increasing corneal eccentricity after both 15 minutes and 6 hours of lens wearing. In many cases, the cornea with small eccentricity also showed the lens rotation larger than $10^{\circ}$. The difference in rotational amount after 15 minutes of toric lens wear was small according to the corneal eccentricity however, the change of rotational amount of contact lens according to corneal eccentricity was shown after 6 hours of lens wear. Conclusions: The present study revealed that the amount of axial rotation was largely varied according to the wearer's corneal eccentricity when wearing toric lens and the rotational amount after certain time of lens was also affected by corneal eccentricity. Thus, it is suggested that the selection of toric soft contact lenses based on corneal eccentricity is necessary.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2C
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• pp.75-81
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• 2008

In this study, a series of laboratory column test on Suction Drain Method which is one of the way to make an soft ground improvement were conducted in order to investigate the effect of the Hardening Zones and the ratio of improvements depending on periods of the improvements and various applied suction pressures. On this occasion, the experimental conditions are followings; in the case of the periods of effectiveness, 4 days, 8 days, 12 days, 16 days, 20 days and in the case of the applied pressures of the Suction are -20 kPa, -40 kPa, -60 kPa and -80 kPa were carried out. As a result of test, settlement increased with suction pressure and duration increase, and gradually converged. Also, as comparing permeability decrease ratio with which calculated back from water content and numerically predicted using Hansbo's radial consolidation theory, measured value was almost coincide with predicted value when permeability decrease ratio was assumed as 2~3. Furthermore, the hardening zone was appeared within 7~8 cm of whole radial (25 cm).

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.86-86
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• 2016

최근 포항가속기연구소 10A 빔라인에 Scanning Transmission X-ray Microscopy (STXM)가 완성되어 운영 중이다. Soft x-ray imaging 장치로서 기술적으로 Sample scanning 기법이 활용된다. 이는 Zone plate를 통해 집속된 빔이 샘플에 조사되고 검출되는 방식이다. 이러한 Scanning 기법을 활용하고 있는 10A STXM은 기본적으로 흡수분광기법 (x-ray absorption spectroscopy)을 이용하고 있다. 특히, 10A 빔라인 STXM은 최고 20 nm까지 공간분해능이 가능하다는 장점이 있다. 따라서 수십에서 수백 나노미터 크기의 시료들 또는 나노구조에 대한 물리화학적 상태 분석이 쉽게 이루어지고 있다. 주로 시료를 투과하면서 흡수되는 X-선 세기 대비를 맵핑하는 형식의 이미지 데이터와 더불어 X-선의 에너지를 조정함으로써 각 에너지에 해당하는 이미지스택을 결과로 얻게 된다. 이러한 이미지 결과로부터 시료의 나노크기에서 오는 물리화학적 상태를 분석하고 물리에서 바이오까지 다양한 분야의 실험 활용이 가능한 상태다.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.3
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• pp.293-300
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• 1999

The purpose of this study was to evaluate the in vitro antifungal effect of several kinds of denture lining materials containing nystatin and silver-zeolite on Candida albicans. Three commercially available tissue conditioners (Soft-Liner, Coe-Comfort, Coe-Soft) and two direct denture relining materials (Tokuso Rebase, Durabase) were selected. In terms of the zone of inhibition and some basic physical properties, I could find the following results ; 1. Nystatin or silver-zeolite included in those relining materials had definite antifungal activities against the Candida albicans. 2. As times went on, both of the antifungal agents's activities decreased gradually. 3. Antifungal agents did not affect the relining materials' basic physical properties. 4 Direct chairside relining materials showed unfavorable dark discoloration with response to silver-zeolite.