• Earthquakes and Structures
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• v.14 no.1
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• pp.73-84
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• 2018

Low cyclic loading tests are conducted on the steel reinforced recycled concrete (SRRC) column-steel (S) beam composite frame joints. This research aims to evaluate the earthquake damage performance of composite frame joints by performing cyclic loading tests on eight specimens. The experimental failure process and failure modes, load-displacement hysteresis curves, characteristic loads and displacements, and ductility of the composite frame joints are presented and analyzed, which shows that the composite frame joints demonstrate good seismic performance. On the basis of this finding, seismic damage performance is examined by using the maximum displacement, energy absorbed in the hysteresis loops and Park-Ang model. However, the result of this analysis is inconsistent with the test failure process. Therefore, this paper proposes a modified Park-Ang seismic damage model that is based on maximum deformation and cumulative energy dissipation, and corrected by combination coefficient ${\alpha}$. Meanwhile, the effects of recycled coarse aggregate (RCA) replacement percentage and axial compression ratio on the seismic damage performance are analyzed comprehensively. Moreover, lateral displacement angle is used as the quantification index of the seismic performance level of joints. Considering the experimental study, the seismic performance level of composite frame joints is divided into five classes of normal use, temporary use, repair after use, life safety and collapse prevention. On this basis, the corresponding relationships among seismic damage degrees, seismic performance level and quantitative index are also established in this paper. The conclusions can provide a reference for the seismic performance design of composite frame joints.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6419-6425
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• 2013

Background: Neoadjuvant chemotherapy (NACT) is a treatment modality whereby chemotherapy is used as the initial treatment of HNSCC in patients presenting with advanced cancer that cannot be treated by other means. It leads to shrinkage of tumours to an operable size without significant compromise to essential oro-facial organs of the patients. The molecular mechanisms behind shrinkage due to NACT is not well elucidated. Materials and Methods: Eleven pairs of primary HNSCCs and adjacent normal epithelium, before and after chemotherapy were screened for cell proliferation and apoptosis. This was followed by immunohistochemical analysis of some cell cycle (LIMD1, RBSP3, CDC25A, CCND1, cMYC, RB, pRB), DNA repair (MLH1, p53) and apoptosis (BAX, BCL2) associated proteins in the same set of samples. Results: Significant decrease in proliferation index and increase in apoptotic index was observed in post-therapy tumors compared to pre-therapy. Increase in the RB/pRB ratio, along with higher expression of RBSP3 and LIMD1 and lower expression of cMYC were observed in post-therapy tumours, while CCND1 and CDC25A remained unchanged. While MLH1 remained unchanged, p53 showed higher expression in post-therapy tumors, indicating inhibition of cell proliferation and induction of apoptosis. Increase in the BAX/BCL2 ratio was observed in post-therapy tumours, indicating up-regulation of apoptosis in response to therapy. Conclusions: Thus, modulation of the G1/S cell cycle regulatory proteins and apoptosis associated proteins might play an important role in tumour shrinkage due to NACT.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.103-112
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• 2017

PURPOSES : In this study, field performance evaluation of crack treatment of pavement and the feasibility of surface treatment of pavement are presented. The performance and cost of preventive maintenance methods have been previously verified, and the methods are being used in many developed countries and cities. However, the performance and cost of the system have not been verified in domestic, field applications. Therefore, in order to improve performance, the field performance is evaluated, and a reasonable cost is proposed. METHODS : Visual Inspection was conducted to evaluate the field application and performance of the preventive maintenance method. In addition, the PCI index was calculated from the results of visual inspection of the application area of the surface treatment method, and the performance life of each method was predicted. For the economic evaluation, life cycle cost analysis was performed using the life cycle cost analysis program. RESULTS :In order to evaluate and quantify the field performance of crack repair material, the residue condition of the pavement surface after crack treatment, rather than the performance of the material, is evaluated. In addition, the crack resistance and performance life of surface treatment methods are evaluated. The cost of currently available treatment methods are compared to the common pavement cut and overlay method, and it is determined that the preventive method is not economical based on life cycle cost analysis. CONCLUSIONS :Because of the characteristics of cracking, it is necessary to conduct the evaluation of currently applied methods and the analysis of the cause of damage, by visual inspection. Moreover, in order to evaluate the performance and economic suitability of the currently applied surface treatment methods, it is necessary to acquire information on application sections by monitoring their long-term conditions and performance.

• Journal of Trauma and Injury
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• v.34 no.1
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• pp.39-43
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• 2021

Purpose: Determining appropriate ways to assess health care quality within the National Health Insurance System is of interest to both the Korean government and the medical community. However, in the trauma field, the number of indicators used to evaluate surgical quality is limited. Using data collected over 5 years at Wonju Severance Christian Hospital Trauma Center in Korea, this study aimed to determine whether the unplanned reoperation rate in the field of trauma surgery could be used to assess the quality of an institution's surgical care. Methods: In total, 665 general surgical procedures were performed at the Trauma Center in 453 patients with abdominopelvic injuries from January 2015 to December 2019. Data were collected from the Trauma Center's data registry and medical records, and included information regarding patients' demographic characteristics, the type of index operation, and the reason for unplanned reoperations. Results: A total of 453 index operations were evaluated. The proportion of patients with an Injury Severity Score (ISS) >15 was 48-70% over the 5-year period, with an unplanned reoperation rate of 2.1-9.3%. Patients had an average ISS score of 17.5, while the average Abbreviated Injury Scale Score was 2.87. Unplanned reoperations were required in about 7% of patients. The most common complications requiring reoperation were recurrent bleeding (26.9%), wound problems (26.9%), intestinal infarction (15.4%), and anastomosis site leakage (7.7%). The procedures most frequently requiring unplanned reoperations were bowel surgery (segmental resection, primary repair, enterostomy, etc.) (24.5%) and preperitoneal pelvic packing (10.6%). Conclusions: The proportion of reoperations was confirmed to be affected by injury severity.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.234-234
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• 2021

국내 기반시설의 대부분은 1970년대 경제성장기에 건설되어 사용연수가 30년 이상 경과하였고 급격한 고령화가 진행 중이다. 1990년대 성수대교와 삼풍백화점의 붕괴는 시설물 유지관리의 중요성에 대한 전국민적 관심을 집중시켰고, 이에 정부는 1995년 「시설물의 안전관리에 관한 특별법」 제정을 시작으로 현재까지 다양한 정책 및 기준을 수립해왔다. 일반적으로 안전점검 및 정밀안전진단 등을 수행하여 시설물의 안전등급을 평가하고 결함에 대한 보수·보강을 실시하여 시설물을 유지·관리하고 있다. 그러나 유지관리 예산은 한정적이기 때문에 모든 결함에 대한 보수·보강 사업을 실시할 수 없는 실정이다. 이에 보수·보강 조치의 우선순위를 선정하는 것이 필요하며, 관련 법령 세부지침에는 부재의 중요도, 결함의 심각성, 경제성을 고려한 우선순위지수(PI, Priority Index)를 제시하고 있다. 이 식은 전문가의 주관적인 판단에 의해 영향도를 50~100%범위 안에서 조정할 수 있으며, 일부 특정 부재는 동일한 가중치가 설정되어 있다. 또한 결정적으로 보수보강을 통한 효과를 효율적으로 고려하지 못하고, 대부분 경제성에 의해 우선순위가 결정되는 한계점이 발생한다. 따라서, 본 연구에서는 몇 가지 사례분석을 통해 현재 우선순위지수에 대한 문제점을 고찰하고 이를 개선할 수 있는 우선순위 산정식(PI)을 제시하였다. 과거 유지관리 시행 초기에는 보수보강 사례가 부족하였지만 현재는 수십년간의 축적된 자료를 바탕으로 제시된 산정식을 충분히 활용할 수 있을 것으로 판단된다. 향후 보수보강 효과를 정량화하는 방법에 대한 추가적인 연구가 수행된다면 더욱 경제적인 측면에서 우선순위를 산정할 수 있을 것이며 노후화된 기반시설 유지관리방안에 효과적으로 사용될 것으로 기대된다.

• Journal of the Korean Society of Food Culture
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• v.22 no.4
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• pp.404-413
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• 2007

This study was carried out to compare UCP2 polymorphism, dietary habits, and obesity index in normal and obese university students. The survey was carried out using self-questionnaires collected from the 126 normal and 60 obese university students. The results are summarized as follows. Breakfast was skipped in 43.7% of normal and 49.3% of obesity students and it appeared obese students eat faster than normal students. The percentage of weight control experience were 49.2 and 71.0 in the normal and obese students, respectively. Blood levels of lipid profiles(triglyceride, LDL cholesterol, and HDL cholesterol), hemoglobin, AST and ALT were anaylzed. In UCP2 genes, the frequency of deletion homozygote(DD) was 71.5%, heterozygote(DI) was 26.9% and insertion homozygote(II) was 1.6%. Plasma levels of triglyceride, total cholesterol, LDL cholesterol, and HDL cholesterol of normal students were 79.06, 172.25, 100.86 and 57.03 mg/dl, and those of obese students were 93.06, 173.22, 101.22 and 54.39 mg/dl, respectively. Blood parameters were in normal range in both group. Plasma triglyceride, total cholesterol and LDL cholesterol levels of obese students were higher than those of normal students. On the other hand, plasma HDL cholesterol levels of obese students were lower than those of normal students. Plasma levels of AST and ALT were in normal range in both group. However, AST and ALT levels of obese students were higher than that of normal students. Thus, it was recommended for them to have a nutritional education program to improve their dietary and living habits for obese students’health. Nutritional education program should also be organized practically and systematically.

• Archives of Plastic Surgery
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• v.38 no.6
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• pp.836-844
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• 2011

Purpose: Hands are the chief organs for physically manipulating the environment, using anywhere from the roughest motor skills to the finest, and since the fingertips contain some of the densest areas of nerve endings on the human body, they are continuously used organ with complex functions, and therefore, often gets injured. To prevent any functional loss, a detailed anatomical knowledge is required to have a perfect surgical treatment. Also it is necessary to have a thorough understanding of arrangements of the human extensor tendons and intertendinous connections when tenoplasty or tendon transfer is required. We performed a study of the arrangements of the human extensor tendons and the configuration of the intertendinous connections over the dorsum of the wrist and hand. Methods: A total of 58 hands from Korean cadavers were dissected. The arrangements of extensor indicis proprius, extensor digitorum communis, and extensor digiti minimi tendons and intertendinous connections were studied. Results: The most common distribution patterns of the extensor tendons of the fingers were as follows: a single extensor indicis proprius (EIP) tendon which inserted ulnar to the extensor digitorum-index (EDC-index); a single EDC-index; a single EDC-middle; a double EDC-ring; an absent EDC-little; a double extensor digiti minimi (EDM), a single EDC-index (98.3%), a single EDC-middle (62%), a double EDC-ring (50%), and an absent (65.5%) or a single (32.8%) EDC-little. A double (70.6%) EDM tendons were seen. Intertendinous connections were classified into 3 types: type 1 with thin filamentous type, type 2 with a thick filamentous type, and type 3 with a tendinous type subdivided to r shaped 3r type and y shaped 3y type. The most common patterns were type 1 in the 2nd intermetacarpal space, type 2 in the 3rd intermetacarpal space, and type 3r in the 4th intermetacarpal space. And in the present study, we observed one case of the extensor digitorum brevis manus (EDBM) on the boht side. Conclusion: A knowledge of both the usual and possible variations of the extensor tendon and the intertendinous connection is useful in the identification and repair of these structures.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.387-390
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• 2008

The importance of the life cycle cost analysis for construction projects of bridge has been recognized over the last decades. Accordingly, theoretical models, guidelines, and supporting softwares have been developed for the life cycle cost analysis of bridges. However, it is difficult to predict life cycle cost considering uncertainties precisely. This paper presents methodology for optimal design of substructure for a steel box bridge. Total life cycle cost for the service life is calculated as sum of initial cost, damage cost considering uncertainty, maintenance cost, repair and rehabilitation cost. The optimization method is applied to design of a bridge substructure with minimal cost, in which the objective function is set to life cycle cost and constraints are formulated on the basis of Korean Bridge Design Specification. Initial cost is calculated based on standard costs of the Korea Construction Price Index and damage cost on the damage probabilities to consider the uncertainty of load and resistance. An advanced first-order second moment method is used as a practical tool for reliability analysis using damage probability. Maintenance cost and cycle is determined by a stochastic method and user cost includes traffic operation costs and time delay costs.

• Journal of Trauma and Injury
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• v.24 no.1
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• pp.7-11
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• 2011

Purpose: Traumatic airway injuries have high rates of mortality and morbidity. Thus, we evaluated the clinical results of trauma-related airway-injury patients. Methods: A clinical analysis was performed for patients with airway trauma who were admitted and treated at the Department of Thoracic and Cardiovascular Surgery, Konyang University Hospital from Dec. 2002 to Dec. 2009. Results: Sixteen patients were admitted and treated. Fourteen patients were male, and the ages of the patients ranged from 16 to 75 years. Six cases were penetrating injuries, 4 were traffic-accident injuries. 3 were fall injuries, and. 3 were other blunt trauma injuries. Anato- mic injuries included 14 trachea cases (87.5%), 1 Rt. main bronchus (6.25%), and 1 Lt. main bronchus cases (6.25%). Diagnosis was made by using computed tomography and bronchoscopy. Five patients were treated with an explothoracotomy, and 7 underwent neck exploration with primary repair. Three patients simply needed conservative management, and 1 patient was treated with a closed thoracostomy. The post-operative mortality rate was 6.25 % (1 patient). Conclusion: Airway trauma is dangerous and should be treated as an emergency, so a high index of suspicion is essential for rapid diagnosis and successful surgical intervention in patients with airway injuries.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.668-674
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• 2002

Structural integrity assessment is indispensable for preventing catastrophic failure of industrial structures/components/facilities. This diagnosis of operating components should be done periodically for safe maintenance and economical repair. However, conventional standard methods for mechanical properties have the problems of bulky specimen, destructive and complex procedure of specimen sampling. Especially, the mechanical properties at welded zone including weldment and heat affected zone could not be evaluated individually due to their size requirement problem. So, an advanced indentation technique has been developed as a potential method for non-destructive testing of in-field structures. This technique measures indentation load-depth curve during indentation and analyzes the mechanical properties related to deformation such as yield strength, tensile strength and work-hardening index. Also indentation technique can evaluate a residual stress based on the concept that indentation load-depth curves were shifted with the direction and the magnitude of residual stress applied to materials. In this study, we characterized the tensile properties and welding residual stress of various industrial facilities through the new techniques, and the results are introduced and discussed.