• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.74-75
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• 2019

There are certain types of construction that produces many defects during the construction of apartment buildings. It may be due to construction errors in the type itself, but more often, it is due to defects derived from other types of construction. Thus, to reduce such secondary defects and prevent fundamental defects in particular types of construction, academic research on the types of construction causing secondary defects should be actively conducted. In addition, as claimed in this study, the industries should work harder to improve the quality of the type of construction that causes secondary defects, rather than just trying to improve the ostensible problems. If the efforts of each sector are backed up, the disputes over defect repair in apartment building construction will reduce in general, which in turn will lead to a reduction in national loss within the construction industry.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.185-186
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• 2005

Intrinsic gettering is usually used to improve wafer quality which is an important factor for reliable ULSI devices. The two-step annealing method was adopted in order to investigate interactions between oxygens and secondary defects during oxygen precipitation process in lightly and heavily boron doped silicon wafers with high energy $^{11}B^+$ ion implantation. Secondary defects were inspected nearby the projected range by high resolution transmission electron microscopy. Oxygen pileup was measured in the vicinity of the projected range by secondary ion mass spectrometry for heavily boron doped silicon wafers.

• Nuclear Engineering and Technology
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• v.46 no.2
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• pp.225-234
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• 2014

Wall-thinned defects caused by accelerated corrosion due to fluid flow in the inner pipe appear in many structures of the secondary systems in nuclear power plants (NPPs) and are a major factor in degrading the integrity of pipes. Wall-thinned defects need to be managed not only when the NPP is under maintenance but also when the NPP is in normal operation. To this end, a test technique was developed in this study to detect such wall-thinned defects based on the temperature difference on the surface of a hot pipe using infrared (IR) thermography and a cooling device. Finite element analysis (FEA) was conducted to examine the tendency and experimental conditions for the cooling experiment. Based on the FEA results, the equipment was configured before the cooling experiment was conducted. The IR camera was then used to detect defects in the inner pipe of the pipe specimen that had artificially induced defects. The IR thermography developed in this study is expected to help resolve the issues related to the limitations of non-destructive inspection techniques that are currently conducted for NPP secondary systems and is expected to be very useful on the NPPs site.

• Journal of the Korean Ceramic Society
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• v.32 no.12
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• pp.1377-1382
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• 1995

A high-resolution transmission electron microscopy study on the lattice defects formed in the high energy P ion implanted silicon was carried out on an atomic level. Results show that Lomer dislocations, 60$^{\circ}$perfect dislocations, 60$^{\circ}$ dislocation dipole and extrinsic stacking fault formed in the near Rp of as-implanted specimen. In the annelaed specimens, interstitial Frank loops, 60$^{\circ}$perfect disolations, 60$^{\circ}$dislocation dipoles, stacking faults, precipitates, perfect dislocation loops and <112> rodlike defects existed exclusively near in the Rp with various annealing temperature and time. From these results, it is concluded that extended secondary defects as well as the point defect clusters could be formed without annealing. Even at low temperature annealing such as 55$0^{\circ}C$, small interstitial Frank loops could be formed and precipitates were also formed by $700^{\circ}C$ annealing. The defect band annealed at 100$0^{\circ}C$ for 1 hr could be divided into two regions depending on the distribution of the secondary defects.

• Applied Microscopy
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• v.16 no.2
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• pp.14-24
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• 1986

The interrelation of secondary defects, intermediate S' phase and aging condition in Al-2.0 wt% Cu-1.1 wt% Mg alloy is studied by transmission electron microscope. The results obtained in this study are as follows. 1. High density of dislocation loops, helices and stacking faults are observed in this specimen with aging treatment. 2. The number of dislocation loops and the width of loop free zone (LFZ) are increased with aging time. 3. The intermediate S' phase precipitates and grows on the dislocations and secondary defects. 4. The misfit dislocations are formed around intermediate S' phase. 5. It is thought that the helices appear to be produced by the climb of screw dislocations, while the dislocation loops appear to be formed both by condensation of vacancies into collapsed discs and by interaction of helices with screw of opposite sign.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.46 no.5
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• pp.361-366
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• 2020

Guided bone regeneration (GBR) is a surgical procedure that utilizes bone grafts with barrier membranes to reconstruct small defects around dental implants. This procedure is commonly deployed on dehiscence or fenestration defects ≥2 mm, and mixing with autogenous bone is recommended on larger defects. Tension-free primary closure is a critical factor to prevent wound dehiscence, which is critical cause of GBR failure. A barrier membrane should be rigidly fixed without mobility. If the barrier is exposed, closed monitoring should be utilized to prevent secondary infection.

• Korean Journal of Materials Research
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• v.13 no.2
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• pp.74-80
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• 2003

The effects of risering design and alloying element on the formation of defects such as external depression, primary and secondary shrinkage cavities in ductile cast iron were investigated. Two types of risering design for the cylindrically step-wise specimen, No. 1(progressive solidification) and No. 2(directional solidification) risering designs, were prepared and six different alloy compositions were casted. In the No. 1 risering design, external depression or primary shrinkage cavities due to liquid contraction were observed in all the specimens from SG 10 to SG 60. The defects caused by liquid contraction seemed to be more affected by risering design than alloying elements. The secondary shrinkage cavities were also observed in all the specimens but a swollen surface was not observed in all the castings. The primary shrinkage cavities were located right under the top surface or connected to the top surface, and were characterized by smooth surfaces. On the other hand, the secondary shrinkage cavities were positioned in the thermal center of the specimen steps 3 and 4, and characterized by rough surfaces. In the No. 2 risering design, no external depression or primary shrinkage cavities due to liquid contraction were observed in all the specimens from SG 10 to SG 60. However, the secondary shrinkage cavities were formed in the thermal center of specimens SG 40, 50 and 60. Like the No. 1 risering design, a swollen surface was not observed in all the castings.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.6
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• pp.666-671
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• 2000

Objectives: This study evaluated the availability of mandibular symphysis corticocancellous block grafts in patients treated for reconstruction of intraoral jaw defects. Materials & Methods: 8 patients with mandibular and maxillary bony defects were treated with corticocancellous block of symphysis. The types of defects included 4 pathologic jaw defects and 4 vertical and/or horizontal alveolar deficiencies. The age ranged from 13 to 45 years. Additional treatments such as plate fixation, alloplastic bony substitutes, and/or barrier membrane application were perfomred. They were evaluated for complications and healing of defects. Follow-up period ranged from 6 to 15 months. Results: 2 patients experienced complications such as wound dehiscence and mild resorption of exposed bone. None of the patients needed secondary operation. Paresthesia of lip, chin, and teeth were recovered completely by 6 months postoperatively. Reconstructed wound showed favorable healing and bony consolidation. Conclusion: Corticocancellous block of mandibular symphysis can be used for the reconstruction of a variety of intraoral local jaw defects selectively. Advantages were easy fixation of graft, possibility of restoration of original alveolar contour, and decreased donor site morbidity.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.10
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• pp.796-803
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• 1998

Intrinsic and proximity gettering are popular processes to get higher cumulative production yield and usually adopt multi-step annealing and high energy ion implantation, respectively. In order to test the combined processed of these, high energy \ulcornerAs\ulcorner ion implantation and 2-step annealing process were adopted. After the ion implantation followed by 2-step annealing, the wafers were cleaved and etched with Wright etchant. The morphology of cross section on samples was inspected by FESEM. The concentration profile of As was measured by SRP. The location and type of secondary defects inspected by HRTEM were dependent on the 1st annealing temperatures. That is, a line of dislocation located at $1.5mutextrm{m}$ apart from the surface at $600^{\circ}C$ lst annealing was changed to some dislocation lines or loops nearby the surface at 100$0^{\circ}C$. The density of dislocation line was reduced but the size of the defects was enlarged as the temperature increased.

• Transactions of Materials Processing
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• v.7 no.5
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• pp.496-504
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• 1998

The eccentric extrusion and bending process for the forming of the curved rectangular hollow tube is newly developed. Generally the bending process of hollow tube is the secondary process followed by the extrusion process of the hollow tube from the round billet. So many defects such as wrinkling and the difference of wall thickness can be happened during the secondary bending process. In order to avoid the defects the new process named as "the eccentric extrusion and bending process" is suggested and applied to the U-bending of rectangular hollow tube. In this paper the kinematically admissible velocity field between the dies surface and the internal plug boundary surface s developed for the curving velocity. By the using of this curving velocity field the curvature of extruded products can be calculated with the parameters such as eccentricity dies length friction constant aspect ratio.