• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.6
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• pp.70-78
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• 2023

The ordinary concentrically braced frame has an advantage of having simple design procedure. For this reason, it has been widely used for the small-sized frame structures subject to moderate or lower magnitude earthquake, even though its seismic performance against the earthquake load is not much effective compared to that of other frame systems. To enhance seismic performance of the ordinary concentrically braced frame where the bracing has a weakness for compressive behavior under lateral earthquake, seismic retrofitting by viscous damper has been commonly introduced. However, the viscous damper, itself, generally does not have stiffness for restoring the structure to the original position. This may cause residual displacement to the structure. In this paper, a self-centering viscous damper system in which upper and lower beams having flexural rigidity play a role as a nonlinear-elastic spring, restoring the spring-damper system subject to external displacement history to its original location, is developed. The numerical analysis for a simplified frame structure shows how including the developed self-centering viscous damper system leads to an enhanced seismic performance of the frame structure through energy dissipation during earthquake excitation.

• Journal of the Korean Society of School Health
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• v.10 no.2
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• pp.241-257
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• 1997

This study identifies a basic framework to analyze specific experiences of examinees so that which nurses are better able to understand reactions of examinees and, further, to provide better nursing treatments to them. This study follows Strauss & Corbin's analysis tool (1990). This basic framework identifies the specific mental reactions in a process away from the "being tightened" state. The main factors explaining this process include the 28 following variables : anxiety, being burdened, being suppressed, lack of agency, being suffocated, term pressure, expectation pressure, grade pressure, firmness, feebleness, helping others, being disturbed, watching others, off ficiousness, staightening on, depending on, getting along with, getting out of, shooting out, giving up, being alone, devoting, bracing up, being industrious, being harassed, being distressed, troubles, and quiting. Twelve variables are factored from the above factors which include pressure, being tighened, terms, expectations, grades, will, friends, family, open-minded confrontation, close-minded confrontation, pursuing, and wandering around. The Examinees' state of being tightened is first developed, watched by others, and finally resolved causing students either to pursue (positive reactions) or to wander around (negative reactions). Based on the theoretical framework, the following sixteen hypotheses are developed : 1. Students are less tightened in the first term. 2. Students are more tightened in the second term. 3. Students with higher grades feel less tightened. 4. Students with lower grades feel more tightened. 5. Students with higher expectations feel more tightened. 6. Students with lower expectations feel less tightened. 7. Students who are less tightened confront open-mindedly. 8. Students who are higher tightened confront close-mindedly. 9. Students with a strong will confront open-mindedly. 10. Students with a weak will confront close-mindedly. 11. Students who have more sincere friends confront open-mindedly. 12. Students who have less sincere frieds confront close-mindedly. 13. Students with family support confront open-mindedly. 14. Students with little family support confront close-mindedly. 15. Students confronting open-mindedly pursue. 16. Students confronting close-mindedly wander. We identify the following four relations from the data analysis : 1. Students with average grades in their first term are more tightened from high expectations and have a tendency to wander if they have less supporting families even if they also have a strong will and sincere friends. 2. Students with low grades in their second term are less tighened because of low expectations and have a tendency to wander if they have a weak will and few sincere friends even if they have strong family support. 3. Students with high grades in their second term are more tightened with high expectations and have a tendency to pursue confrontations open-mindedly if they have supporting families and a strong will even if they have few sincere friends. 4. Students with average grades in their first term are less tightened from fewer expectations and have a tendency to pursue confrontations open-mindedly when they have more supporting families and sincere friends even if they have a weak will. A Student's degree of being tightened are affected by grades, terms, and expectations. Being tightened is resolved positively or negatively based on will, friends, and family. We conclude that will, family support, and sincere friends cause students to confront "being tightened" open-mindedly. We also conclude that practical nursing for students who are tightened have to focus on creating environments in which students are able to confront open-mindedly.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.190-211
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• 2010

The purpose of this paper is to provide the preliminary data for maintenance of old trees of natural monuments and establishing protection projects. Accordingly, growth conditions, location circumstances, environment and protection management were analyzed for old trees at 34 sites in Gyeongsangbuk-do. Tree forms, crown, trunk and trees' health, leaves volume were analyzed in survey sites. As the results, the growth of Picrasma quassioides in Songsadong, Andong-si and Catalpa ovata in Hongwon-ri, Cheongsong-gun were not in good condition, along with other old trees of 6 cities (Quercus variabilis in Susan-ri, Uljin-gun, Juniperus chinensis in Hujeong-ri, Uljin-gun, Pyrus ussuriensis in Ssangjeon-ri, Uljin-gun, Salix glandulosa var. pilosa in Deokchon-ri, Cheongdo-gun, Pinus densiflora for. multicaulis in Hwasan-ri, Mungyeong-si, Pinus densiflora in Daeha-ri, Mungyeong-si). Accoding to these results, protection project and consistent monitoring are necessary. The analysis results of growth conditions per location circumstances showed that the old trees in the small spaces with large traffic of people were in bad condition. Therefore, it is necessary to secure sufficient space and soil improvement for such trees. The analysis results of growth conditions per species showed that Zelkova serrata, Quercus spp., Pinus densiflora are in good condition while Salix koreensis and others, i.e. a singular tree, are in poor condition. Thus, relatively smaller individuals and separately situated trees need careful management in their protection. The analysis results of trunk's growth ratio showed that Pinus densiflora, Ginkgo biloba, Zelkova serrata are in good condition whereas Juniperus chinensis, Quercus variabilis, Salix koreensis are not. It is a recent trend that tree surgeries are gradually decreasing; there are a number of damaged trees with no maintenance/management, and several sites requiring mend trunks management and cabling, bracing in protection and management projects. Hence, in the future, local government and management organizations should plan for systematic management and establish a protection plan for the natural monument trees. Also, 12 sites were found to be in need to purchase lands in order to secure the growth spaces, and since most of these areas are available for purchase, it is needed to promote a budget and purchase those areas through persuasion of the owner. These areas seems crucial in order to maximize the effect of conservation efforts and budgets for the preservation and restoration of the old trees.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.1
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• pp.37-46
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• 2006

Purpose: To evaluate the end results between the surgical treatment with neo-adjuvant chemotherapy in Korea and non-invasive high intensity focused ultrasound (HIFU) technique in China for osteogenic sarcomas. Materials and Methods: The surgical treatment with neoadjuvant chemotherapy for total 67 cases (4 IIA, 58 IIB, and 5 III) in Korea since 1993 and the HIFU therapy for total 71 cases (57 II and 14 III) in China since 1997 was performed. In Korea, neo-adjuvant chemotherapy in 66 cases out of total 67 patients, but the adjuvant chemotherapy in only one case was done. On the contrary, in China, full chemotherapy for more than 9 times for 37 patients with stage II out of total 71 cases, but for less than 8 times of partial chemotherapy for 23 patients (stage II) and 14 patients (stage III) was done. The surgical treatment in total 67 Korean patients was done with wide resection and reconstruction for 56 patients, but wide resection without reconstruction for 5 patients and amputation for 6 patients. In china, total 71 patients was treated with average 1.5 times (1~4 times) of HIFU, and if there are some evidences of residual tumor after HIFU with following MRI, the second HIFU therapy was given 2~4 weeks later. After then, the bony defect was in no touch, keep bracing for long time expecting regeneration. All of them were followed for average 46 Mo (12~150 Mo) in Korea, but followed for average 22 Mo (9 years~8 months) in China. Results: The 5 year survival rate (stage II), was average 92.7% (IIA 100%, IIB 85.5%) in Korea series, and average 78.7% (full chemotherapy 91.8%, part chemotherapy 56.6%) in China series. The 3 year survival rate (stage III) was 20% in Korea and 7.1% in China. So, the final overall survival rate was 65.2% in Korea and 51.8% in China. The overall functional outcome score by ISOLS was 24.3 (81%) in Korea and 19.8 (73%) in China. There are 25.4% (17/67 cases) of complications in Korea and 31% (27 complications in 22 patients out of total 71 cases) in China after each treatment. Conclusions: The end results of Korea series which was treated with neoadjuvant chemo- and surgical methods are better than that of non-invasive thermal ablation in china. But we also believe the HIFU, as one of, was also effective to decrease the local recurrence and symptomatic releaf for stage II or even in III of osteogenic sarcomas.