• Journal of Chest Surgery
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• v.42 no.2
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• pp.279-281
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• 2009

A 38-year old man was admitted to our hospital due to a $5{\times}6cm$ sized pulsating mass in the right neck. He suffered from intermittent neck pain and hoarseness for two months due to the rapidly growing mass. The radiological examinations revealed an aneurysm of the right common carotid artery near the bifurcation, and it was compressing the internal and external carotid arteries. Endarterectomy of the right internal carotid artery, aneurysmectomy of the right common carotid artery and graft interposition were done, while the cerebral circulation was maintained by an internal shunt. Intraoperative injury to the nerve tissue around the aneurysm was avoided. He was discharged on the postoperative 7th day without any complications.

• International Journal of Highway Engineering
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• v.9 no.2 s.32
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• pp.27-37
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• 2007

This research was conducted to determine the optimum lifting positions on precast concrete slabs for precast concrete pavement construction, based on the analysis of concrete stress distribution under various lifting conditions. To analyze stresses in concrete slabs, the finite element method was implemented and a numerical model of the precast slab that was going to be used in the experimental construction was developed. Changes in the stress distribution due to the lifting angle were investigated because slab lifting is not always performed in the perpendicular direction to the slab surface. In addition, the effect of the lifting level, the distance between the neutral axis of the slab and the lifting point, on the stress distribution was investigated since the lifting point is not always at the neutral axis of the slab. To consider the actual steel design of the precast slab, the effect of the reinforcement near the lifting point was also investigated. From this study, the optimum lifting positions of the precast slabs were determined according to the lifting angle and level, and the results were compared with the lifting positions used in the PCI standards.

• Journal of the Earthquake Engineering Society of Korea
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• v.15 no.4
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• pp.13-21
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• 2011

Seismic structure pounding between adjacent superstructures may induce the destruction of pier and bridge superstructures and cause local damage that leads to the collapse of the whole bridge system. The pounding problem is related to the expansion of joints, gap distance and seismic response of the abutments. In this research, methods of the contact element approach, the linear spring model, the Kelvin-Voigt model and the Hertz model were studied to analyse the pounding characteristics. The shaking table test for a model specimen such as a bridge superstructure with elastomeric bearings was performed to evaluate the contact element approach methods. Relationships between the time history response from the numerical analysis results and the measured response from the shaking table test are compared. The experimental results were not well matched with the numerical analysis results using the existing pounding stiffness models. Therefore, in this study, coefficients are proposed to calculate the appropriate pounding stiffness ratio.

• The Journal of the Korean bone and joint tumor society
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• v.18 no.2
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• pp.83-88
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• 2012

We reviewed the clinical features of 2 patients who underwent surgery for subungal exostosis, focusing on postoperative deformity of the nail. The lesion destroyed the nail bed and was excised with a direct approach. then thin split-thickness sterile matrix graft was done after excision of the tumor because the defect of the nail bed was large. Good postoperative appearance of the nail was obtained by thin split-thickness sterile matrix graft. The use of thin split-thickness sterile matrix graft for the replacement of a nail bed defect can regain a smooth, adherent, and normal-looking nail and avoid donor-site morbidity. Thin split-thickness toe-nail bed graft is a good choice for the prevention of postoperative deformity.

• Journal of the Korean Geotechnical Society
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• v.16 no.1
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• pp.107-116
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• 2000

Dynamic and static load tests are conducted in four construction sites by using steel pipe piles(SPP) and concrete piles to compare differences of load bearing mechanism. Steel pipe piles are instrumented with electric strain gages and are subject to dynamic load tests during driving. The damage of strain gages attached is checked simultaneously. Static load test is also conducted on the same piles after two to seven days' elapse. Then load-settlement behavior and shaft and/or tip resistances are measured. As a result, the allowable bearing capacity calculated by the Davisson's offset method of CAPWAP analysis shows 2~33% larger than that of static load test. The average value of allowable bearing capacity of static load test is closer to the allowable capacity obtained at the safety factor of 2.5 applied on ultimate bearing capacity than to the one obtained from the Davisson's offset method. The analysis of strain gage readings shows that unit skin friction increases with depth. Furthermore, the friction mobilized around the 1~2m above the pile tip considerably contributes to the total shaft resistance.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.06a
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• pp.109-110
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• 2009

"드럼 코아시편 채취장치" 는 침출/내수성 시험, 압축강도 측정시험, 열 순환 시험등 의 파괴적 물성시험을 수행하기 위해서 경질(시멘트 고화체) 및 연질(파라핀왁스) 등의 방사성폐기물드럼으로부터 코아 시료를 채취하는 장비이다, 시편채취의 최대길이는 860 mm 이며 코아 시편의 직경은 50~200 mm 이며 일반적으로 "방사성폐기물 고화체의 물성시험"에 사용되는 시편은 실험실적으로 제조한 소규모 모의 고화체 시편과 고화공정에서 직접 채취한 소규모 시편, 200L 드럼으로부터 코아시편을 채취 가공하여 만든 시편과 같이 3종류가 있다. 고화공정에서 발생되는 고화체는 일반적으로 200 L 드럼에 주입되며, 고화체의 균일성 정도는 고화공정의 특성, 폐기물/고화매질 혼합비, 200 L 고화체 드럼의 냉각방식에 따라 다르다. 따라서, 실험실에서 제조한 시편과 공정에서 채취한 소규모시편은 실제 고화공정을 대표할 없으며 또한 실제 발생된 고화체의 조성과도 동일하다고 볼 수 없다. 따라서 200 L 드럼으로부터 코아시편을 채취하여 만든 시편이 고화공정과 고화체를 대표할 수 있는 시편으로 볼 수 있다 그러므로 고화체 및 고화공정을 대표할 수 있는 코아시편을 채취할 수 있는 장치를 제작하여 다양한 코아시편을 200 L 고화체 드럼으로부터 수직 코아시편을 채취할 필요가 있으며 실험에서 코아시편 채취속도와 연관된 Z-AXIS 의 Rpm은 운전범위는 0-2000 Rpm 이나 이때 너무 빠른 속도는 기계에 치명적인 손상을 초래 할 수 있으므로 위험한 것으로 나타났으며 500-1000 Rpm 의 속도가 적합한 것으로 시험되었으며 시편을 절삭하는 Spindle의 Rpm은 운전범위는 0-1500Rpm 이나 무리한 운전을 피해 가장 적절한 Speed로 운전해야하며 시험결과 500-800Rpm 이 최적운전범위로 나타났다 또한 시멘트고화체에서의 코아 채취시험에서는 Spindle의 속도는 500 Rpm, Z -AXIS 의 Rpm은 900 Rpm이 가장 적합한 것으로 나타났으며 성능평가시험을 통하여 비트부의 절삭속도와 Z축의 이동속도에 관한 그라프를 획득하였으며 시편의 크기에 따라서 Spindle의 속도를 증감하여야함을 확인할 수 있었다.

• Journal of Veterinary Clinics
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• v.17 no.2
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• pp.368-375
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• 2000

개의 개흉술이나 개심술 후에 주요 합병증인 유착에 대한 sodium carboxymethyl- cellulose (SCMC)의 효과를 평가하기 위하여 1% SCMC총액을 흉막 및 심낭에 적용하였다. 10두의 개를 SCMC투여 군과 생리식염수 투여 군으로 각각 5두씩 배치하고, 개흉 후 4번째 메서 7번째 늑골의 늑연골 연접부 부위에 찰과상을 유도하였고 심낭 절개 후 심낭의 내측 및 닿는 심근에 각각 $2{\times}2cm$크기로 찰과상을 유발하였다. 찰과상 유발 후 생리식염수 투여 군은 멸균 생리식염수를 3.5m1/kg을, SCMC투여 군은 같은 용량의 1% SCMC를 흉강 및 심낭 내에 각각 도포 하였다. 수술 전후에 CBC와 혈장 plasminogen치를 측정하였다. 유착 정도 는 수술 30일 후에 0-4로 점수화하여 판정하였다 십장과 심낭의 평균 유착치는 SCMC투여 군이 2.4$\pm$0.8, 생리식염수 투여군이 $3.7{\pm}0.9$로 나타나 SCMC 투여군에서 유착 발생이 유의 성 있게 낮았다(p<0.01). 폐염과 흉막간의 평균 유착치는 SCMC 투여군이 1.7$\pm$0.2이었고, saline 투여군은 $3.5{\pm}0.8$로. SCHC투여 군에서 유착 발생이 유의성 있게 낮았다(p<0.01). Saline 투여군의 혈중 plasminogen 농도는 술 후 1일에 $28.2{\pm}5.677$로 감소하였고,술 후 7일에 $47{\pm}1.4%$.증가하였다(p<0.05). SCMC 투여군에서는 실험적 수술 1일 후 $27.1{\pm}10.3$로 감소하였고 7일 후에는 $30.3{\pm}21.6%$로 증가(p<0.01)하였으나 두 군간의 유의적인 차이는 없었다 이 상의 결과로 볼 때 개흉술 및 개심술시 1% SCMC를 투여하여 흉강 내의 유착을 방지함으로써 재수술이 필요한 경우에 수술의 어려움과 조직손상의 위험을 감소시킬 것으로 사료된다.로 사료된다.

• Korean Journal of Heritage: History & Science
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• v.46 no.2
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• pp.136-149
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• 2013

We studied the characteristics and the growth mechanism of surface cracks from the Naksansa seven-storied stone pagoda(Treasure No. 499). The pagoda is composed of both medium-grained, porphyritic biotite granite and hornblende-biotite granite. Alkali feldspar megacrysts are easily found as phenocrysts in the rocks. Surface cracks intensely developed at the lower part of the stone pagoda, and their directions are of vertical, horizontal, and diagonal. The rocks of the pagoda have intrinsic microcracks which can be defined as rift and grain rock cleavages. Both rock cleavages seems likely to have led to the crack growth and consequently to the mechanical deterioration of the pagoda. The vertical cracks developed parallel to the vertical compressive stress, whereas horizontal ones formed by tensile strength normal to the vertical compression. In addition mineral cleavages and twin planes of alkali feldspar phenocrysts seems to have been closely related to the mechanical breakdown of the rocks in the NE part of the pagoda.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.167-175
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• 1998

Purpose : It is not a simple task to achieve the ideal isodose curve with a standard vaginal applicator or sing1e plane needle impant in the paravaginal tissue when primary or recurrent gynecological neoplasms(cervical cancers, vaginal cancers and vulvar cancers) are treated as a boost following external beam radiotherapy. The authors introduce the development and construction of a simple, inexpensive, customized applicator for volume implant to maximize the radiation dose to the tumor while minimizing the dose to the rectum and the bladder. Materials and Methods : Nine patients underwent Ir-192 transperineal interstitial implantation for either recurrent(5 cases) or primary(3 cases) cervical cancers or primary vaginal cancer(1 case) between August 1994 and February 1998 at Ajou university hospital. First 3 cases were performed with a sing1e plane implant guided by digital palpation. Because of inadequate isodose coverage in the tumor volume in first 3 cases, we designed and constructed interstitial vaginal applicator for volume implant to improve tumor dose distribution and homogeneity while sparing the surrounding normal tissue. Our applicators consist of vaginal obturator and perineal template that made of the clear acrylamide and dental mold material$(Provil^{(R)})$. The applicators were customized individually according to the tumor size and its location Both HDR and LDR irradiation were given with these applicators accomodating 6 Fr needles(Microselectron Nucletron). The pretreatment planning prior to actual implant was performed whenever possible. Results : Needles can be inserted easily and evenly into the tumor volume through the holes of templates, requiring less efforts and time for the implant procedure. Our applicators made of materials available from commercial vendors. These have an advantage that require easy procedure, and spend relatively short time to construct. Also it was possible to fabricate applicators to individualize according to the tumor size and its location and to achieve the ideal isodose coverage. We found an accurate needle arrangement and ideal dose distribution through the CT scan that was obtained in 3 cases after needle implant. Three patients with primary cervical and vaginal cancers were controlled locally at final follow up. But all recurrent cases failed to do so. Conclusion : The authors introduce inexpensive, simple interstitial vaginal templates which were self-designed and constructed using materials available from commercial vendors such as acrylanide and dental mold material $(Provil^{(R)})$.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.993-999
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• 2008

A girder height limitation is the critical parameter for rapid construction of bridge deck and construction space limitation especially in urban area such as high population area and high density habitats. A standard post-tensioned I-shaped concrete girder usually demands relatively higher girder height in order to retain sufficient moment arm between compression force and tensile force. To elaborate this issue, a small U-shaped section with wide flanges can be used as a possible replacement of I-shaped standard girder. This prestressed concrete box girder allows more flexible girder height adjustment rather than standard I-shaped post-tensioned girder plus additional torsion resistance benefits of closed section. A 30m-long, 1.7m-high and 3.63m-wide actual small prestressed concrete box girder is designed and a laboratory test for its static behaviors by applying 6,200kN amount of load in the form of 4-point bending test was performed. The load-deflection curve and crack patterns at different loading stage are recorded. In addition, to extracting the dynamic characteristics such as natural frequency and damping ratio of this girder, several excitation tests with artificial mechanical exciter with un-symmetric mass are carried out using operational frequency sweep-up. Nonlinear finite element analysis of this 4 point bending test under monotonic static load is investigated and discussed with aids of concrete damaged plasticity formulation using ABAQUS program.