• Journal of the Korean Wood Science and Technology
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• v.52 no.3
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• pp.243-261
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• 2024

In this study, samples were collected from various ancient wooden shipwrecks, including the Shinan shipwreck and Jindo shipwreck that used iron nails, the Yeongheungdo shipwreck carrying iron artifacts, as well as the Sibidongpado shipwreck and Wando shipwreck where degradation products were not observed, all of which were salvaged by the National Research Institute of Maritime Heritage. The aim was to analyze the characteristics of degradation products generated by iron (Fe) within the salvaged wooden shipwreck materials and establish fundamental data on degradation products in waterlogged archaeological wood. The analysis revealed that sulfur (S) is generally accumulated in wood obtained from marine environments. It was observed that the content of inorganic substances such as iron and sulfur was significantly higher in the Shinan shipwreck, Jindo shipwreck, and Yeongheungdo shipwreck compared to Sibidongpado shipwreck and Wando shipwreck, which used wooden nails. This indicates that the presence of iron affects the accumulation of degradation products and suggests that iron is a factor in the corrosion of wood. Furthermore, crystallin compounds were observed within the cell walls, and higher concentrations of iron and sulfur were found in the resin ducts, rays, and radial tissues. This suggests that during desalination and consolidation treatments, warm water or polyethylene glycol (PEG) may move degradation factors into resincanals, rays, radial tissues, etc.

• Journal of Yeungnam Medical Science
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• v.9 no.1
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• pp.130-136
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• 1992

Fractures of the tibial shaft are the most common among the long bone fractures, and have much difficulty in treatment due to their enumerous complications. Thirty patients with fractures of the tibial shaft were treated with Ender nails under the image intensifier at the Department of Orthopedic Surgery, Yeungnam University Hospital from December 1986 to November 1991. The following results were observed. 1. The average age was 37.3 years and the number of male was three times of the female. The most common cause was traffic accident. 2. Twenty cases out of thirty one were closed fractrure and the remaining 11 were open. The comminuted and segmental fractures were 18(57.7%) in number and the most common fracture site was the middle one third(53%). 3. Average interval from injury to operation was 7.6 days and 19 cases showed associated injuries. 4. The mean duration of the bone union was 18.9 weeks and 2 cases showed the delayed union. 5. Twelve complications were noted such as shortening, varus deformity, delayed union, ankle motion limitation, nail irritation, and soft tissue infection.

• Journal of the Korea Concrete Institute
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• v.15 no.6
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• pp.848-855
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• 2003

During concrete placement, the partially distributed load due to the concrete placement paths creates the lateral force in the connection parts of the shore. In order to restrain this lateral force, the nails must be used in the upper and lower connection parts of shores. But, for the convenience of the construction and dismantling of the shores, the workers hardly use the nails. In this case, the connections of shore cannot resist the shear force and rotation. And this situation may cause the collapse of form-shore system. Therefore, contact and spring models for the connection analysis of the form-shore systems are required. If we take into account this construction situation, we need to understand the effects of shear and rotation stiffness according to the several types of connection parts in shores as a case study. This study evaluates the shear and rotation stiffness of the connection parts of shores according to the variations of the lengths, numbers and positions of nails, and then presents the experimental results depending on the end conditions of shores. And, these results can be used as a spring model and critical load evaluation data for the connection analysis of form-shore system.

• Journal of the Korean Chemical Society
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• v.64 no.4
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• pp.203-209
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• 2020

Selenium species in hair and nails were extracted, separated and analyzed with HPLC-ICP/MS. The result showed that Se species was mostly SeCys and the information related to the change of selenium concentration in a body could be obtained. The Se fortification study was performed for 5 participants during 12 months. The average of Se concentration was 858.6 ± 201.2 ng g^-1, which did not change much during the research period nor the difference between the individuals was striking. In the case of hair, the average concentration was 205.3 ng g^-1 which was lower than nails. Se supplement of 22 ㎍ day^-1 was taken for 3 months by the volunteers and the difference between before and after (3 months period for each) the taking of supplement was not striking. However, when the dose was increased to 300 ㎍ day^-1 for 2 months, the concentration was increased noticeably to 1,230 ng g^-1. It can be thought that the analysis of finger nail for Se can provide valuable information for the long period (several months) of exposure or intake of Se for a human body.

• Journal of the Korean Geotechnical Society
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• v.20 no.7
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• pp.197-206
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• 2004

The ground anchor support system may not be occasionally used because of space limitations in urban excavation sites nearby the existing structures. In this case, soil nailing system with relatively short length of nails could be efficiently adopted as an alternative method. The general soil nailing support system, however, may result in excessive deformations particularly in an excavation zone of the existing weak subsoils. Pretensioning the soil nails then could play important roles to reduce deformations mainly in the upper part of the nailed-soil excavation system as well as to improve local stability. In this study, a newly modified soil nailing technology named as the PSN (Pretension Soil Nailing), is developed to reduce both facing displacements and ground surface settlements in top-down excavation process as well as to increase the global stability. Up to now, the analytical procedure and design technique are proposed to evaluate maximum pretension force and stability of the PSN system. Also, proposed are techniques to determine the required thickness of a shotcrete facing and to estimate probability of a failure against the punching shear, Based on the proposed procedure and technique, effects of the radius of a influence circle and dilatancy angle on the thickness of a shotcrete facing, bonded length and safety factors are analyzed. In addition, effects of the reduction of deformations expected by pretension of the soil nails are examined in detail throughout an illustrative example and the $FLAC^{2D}$ program analysis. And a numerical approach is proposed PSN system using the shear strength reduction technique with the $FLAC^{2D}$ program.

• The Journal of Engineering Geology
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• v.28 no.4
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• pp.605-618
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• 2018

Korea follows the slope design criteria during construction. It was enacted by the Ministry of Land, Transport and Maritime Affairs. There are cases where the Soil-nail is designed as a measure to secure slope stability. The arrangement of the soil-nail may be arranged at equal intervals or may be arranged differently depending on the soil failure model. The optimum design of the countermeasure method is determined by securing stability of the slope through optimization of dimensions and shape. However, when uniform nails are placed at low elevations in slopes, the standard safety factor is exceeded, which may hinder economic design. It is preferable to arrange the reinforcement of the nails over the entire slope. When the horizontal spacing of the nails was topology optimized according to the slope height, it was possible to minimize the amount of reinforcement while satisfying the standard safety factor. Since the active load is reduced in the section where the slope height is lowered, the safety factor after reinforcement may be excessively increased. Therefore, the phase optimization method is proposed as an economical optimal design method using the reinforcing shape density. In addition, a relational expression was designed to optimize the horizontal spacing by slope height.

• Journal of Conservation Science
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• v.37 no.2
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• pp.179-189
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• 2021

In this study, the research objects are gilt plated silver-iron nails excavated from the west of the tombs in Neungsan-ri, Buyeo. A gilt plated silver-iron nail was fabricated by combining silver and iron via heating and then gilding amalgam on top of this combination, demonstrating that this ancient artifact that can be replicated using current technology. Since the metal (Au, Ag) surface of these gilt plated artifacts are covered with iron oxide, which slips into the cracks and scratches of the artifacts as well, desalination is essential. Based on the results of the preliminary experiment, the research objects were classified into grades A, B, and C, according to the degree of corrosion and then desalinated using an alkali solution (NaOH, Sodium Sesquicarbonate of 0.1 M) at 60℃. The results demonstrate that the more serious is the degree of corrosion, the more is the amount of Cl^- detected. Further, more Cl^- was released when NaOH was used than when sodium sesquicarbonate was used, for all grades except Grade A. Furthermore, the more serious is the degree of corrosion, the longer is the desalination period and the reaction with NaOH for all grades except Grade A. A comparison of the Fe composition of the surface before and after desalination shows that Fe composition is the use of NaOH resulted in a smaller increase compared with the use of sodium sesquicarbonate, for all grades except Grade B. However, four of the nails were damaged owing to NaOH (Grade B 3ea, Grade C 1ea) during desalination. Thus, Cl^- ions are more stably released when sodium sesquicarbonate is used than when NaOH is used.

• Journal of Convergence for Information Technology
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• v.11 no.7
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• pp.210-222
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• 2021

This study surveyed 289 beauty specialized high school students to analyze the relation between beauty curriculum awareness, career education satisfaction, and career decision efficacy. The beauty curriculum was concentrated towards the hair major and technical education for license acquisition, and the career plans were high in employment and college entrance admission. In terms of awareness and satisfaction of the beauty curriculum, nails and entrepreneurship were low (p<0.05, p<0.001), nails were low in career decision efficacy, and makeup and entrepreneurship was low in career education satisfaction (p<0.01, p<0.05). The career education satisfaction was higher as the beauty curriculum awareness rises, and educators had a positive influence on career education satisfaction. The following areas had the positive influence for each section; the school operation and facility area for job information, the curriculum area for future planning and problem solving, and the educator area for self-evaluation (p<0.05, p<0.001, p<0.001). Therefore, it is necessary to improve the curriculum in the majors of make-up, skin, and nails, and effective career education programs should be developed.

• Proceedings of the Korean Geotechical Society Conference
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• 1994.09a
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• pp.119-122
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• 1994

An analytical procedure is described to estimate the mobilized tensile forces along the effective lengths of nails. Based on the horizontal focing displacements of a nailed-soil wall experiencing outward tilt about the toe with granular soil deposit, the variation of nail-soil friction coefficient is modeled. Also, the method of overall stability analysis of a nailed-soil wall is presented using the Morgenstem-Price limit-equilibrium slice method. The results predicted by the developed procedure are compared with test measurements. The comparisons show in general good agreement.

• Journal of Korean Foot and Ankle Society
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• v.12 no.1
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• pp.100-105
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• 2008

Partial toenail ablation on both sides of the great toenail, unfolding the severely curved toenail, and application of a simple device for maintaining the unfolded state of the incurved toenail is described to treat severely incurved toenails (pincer nails). This technique alleviated symptoms and improved the shape of severely curved toenails of the greater toe.