• Journal of the Korean Wood Science and Technology
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• v.50 no.2
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• pp.134-147
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• 2022

The objective of this study is to determine the effect of fiber direction arrangement and layer composition of hybrid bamboo laminate boards on the physical and mechanical properties. The raw material used was tali bamboo (Gigantochloa apus (J.A. & J.H. Schultes) Kurs) rope in the form of flat sheets (zephyr) and falcata veneer (Paraserianthes falcataria (L) Nielsen). Zephyr bamboo was arranged in three layers using water-based isocyanate polymer (WBPI) with a glue spread rate of 300 g/m². There were variations in the substitution of the core layer with falcata veneers (hybrid) as much as two layers and using a glue spread rate of 170 g/m². The laminated bamboo board was cold-pressed at a pressure of 22.2 kgf/cm² for 1 h, and the physical and mechanical properties were evaluated. The results showed that the arrangement of the fiber direction significantly affected the dimensional stability, modulus of rupture, modulus of elasticity, shear strength, and screw withdrawal strength. However, the composition of the layers had no significant effect on the physical and mechanical properties. The bonding quality of bamboo laminate boards with WBPI was considered to be quite good, as shown by the absence of delamination in all test samples. The bamboo hybrid laminate board can be an alternative based on the physical and mechanical properties that can meet laminated board standards.

• Journal of English Language & Literature
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• v.57 no.3
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• pp.473-493
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• 2011

This paper aims, first, to trace the trajectory of Sebastian Barry's dramatic works in terms of retrieving the hidden (hi)stories of his family members, and second, to analyze his most successful play to date in both critical and commercial senses, The Steward of Christendom, in terms of the tension or even rupture between Irish national history and the dramatic representation of it. If contemporary Irish drama as a whole can be seen as an act of mirroring up to nation, Barry's is a refracting than reflecting act. Whereas modern Irish drama tends to have helped, however inadvertently, consolidate the nation-state by imagining Ireland through its other (either in the form of the British empire or the Protestant Unionist north), Barry's drama aims at cracking the surface homogeneity of Irish identity by re-imagining "ourselves" (a forgotten part of which is a community of southern Catholic loyalists). Furthermore, the "ourselves" re-imagined in Barry's drama is more fractured than unified, irreducible in its multiplicity than acquiescent in its singularity. The playwright's foremost concern is to retrieve the lives of "history's leftovers, men and women defeated and discarded by their times" and re-member those men and women who have been expunged from the imagined community of the Irish nation. This he does by endowing "every life" with "an after-life" and "every demon" with "a fairy tale." The Steward of Christendom is Barry's dramatic attempt to bestow upon the historically demonized Thomas Dunne, an Irish policeman in the British Empire, his fairy-tale redemption.

• Journal of Welding and Joining
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• v.15 no.1
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• pp.101-108
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• 1997

In repaired weldment of ASTM A-470 class 8 high pressure stream turbine rotor steel, creep rupture life was studied in relation with carbide morphology. Carbides were identified using carbide extraction replica method. A retired rotor has molybdenum rich carbide $M_2C$, lndacochea vanadium rich carbide $M_4C_3$, and chromium rich carbides $M_{23}C_6$and $M_7C_3$. Weldments ruptured at ICHAZ showed that some of carbides have been transformed into spherical types of coarsened carbides at ruptured area. Those carbides were revealed as molybdenum rich $M_6C$ carbide and they provided cavitation sites due to molybdenum depletion around $(M_6C)$ carbide. However coarsened $M_6C$ and $M_{23}C_6$ carbides were observed at ruptured area in case of ruptured at CGHAZ.

• Journal of Power System Engineering
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• v.9 no.4
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• pp.96-101
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• 2005

Magnesium alloys have been widely used for many structural components of automobiles and aircraft because of high specific strength and good cast ability in spite of hexagonal closed-packed crystal structure of pure magnesium. In this study, uniaxial tension tests at high temperature and creep tests are done in order to investigate the characteristics of high temperature and mechanisms for creep deformation of AZ31 Mg alloy. Yield stress and ultimate tensile stress decreased with increasing temperature, but elongation increased from results of uniaxial tension test at high temperature. The apparent activation energy Qc, the applied stress exponent n and rupture life have been determined during creep of AZ31 Mg alloy over the temperature range of 473K to 573K and stress range of 23.42 MPa to 93.59 MPa, respectively, in order to investigate the creep behavior. Constant load creep tests were carried out in the equipment including automatic temperature controller, whose data are sent to computer. At around the temperature of $473K{\sim}493K$ and under the stress level of $62.43{\sim}93.59%MPa$, and again at around the temperature of $553K{\sim}573K$ and under the stress level of $23.42{\sim}39.00MPa$, the creep behavior obeyed a simple power-law relating steady state creep rate to applied stress and the activation energy for the creep deformation was nearly equal, respectively, and a little low to that of the self diffusion of Mg alloy including aluminum. Also rupture surfaces at high temperature have had bigger dimples than those at lower temperature by SEM.

• Journal of Trauma and Injury
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• v.34 no.2
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• pp.81-86
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• 2021

Purpose: This study investigated the clinical outcomes of trauma patients with blunt thoracic aortic injuries at a single institution. Methods: During the study period, 9,501 patients with traumatic aortic injuries presented to Trauma Center of Gil Medical Center. Among them, 1,594 patients had severe trauma, with an Injury Severity Score (ISS) of >15. Demographics, physiological data, injury mechanism, hemodynamic parameters associated with the thoracic injury according to chest computed tomography (CT) findings, the timing of the intervention, and clinical outcomes were reviewed. Results: Twenty-eight patients had blunt aortic injuries (75% male, mean age, 45.9±16.3 years). The majority (82.1%, n=23/28) of these patients were involved in traffic accidents. The median ISS was 35.0 (interquartile range 21.0-41.0). The injuries were found in the ascending aorta (n=1, 3.6%) aortic arch (n=8, 28.6%) aortic isthmus (n=18, 64.3%), and descending aorta (n=1, 3.6%). The severity of aortic injuries on chest CT was categorized as intramural hematoma (n=1, 3.6%), dissection (n=3, 10.7%), transection (n=9, 32.2%), pseudoaneurysm (n=12, 42.8%), and rupture (n=3, 10.7%). Endovascular repair was performed in 71.4% of patients (45% within 24 hours), and two patients received surgical management. The mortality rate was 25% (n=7). Conclusions: Traumatic thoracic aortic injuries are life-threatening. In our experience, however, if there is no rupture and extravasation from an aortic injury, resuscitation and stabilization of vital signs are more important than an intervention for an aortic injury in patients with multiple traumas. Further study is required to optimize the timing of the intervention and explore management strategies for blunt thoracic aortic injuries in severe trauma patients needing resuscitation.

• Journal of the Korean Society of Radiology
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• v.83 no.5
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• pp.1121-1127
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• 2022

Endometriosis-related symptoms are believed to be alleviated during pregnancy. However, pregnancy complications, such as pseudoaneurysm of the uterine artery, rupture of ovarian or uterine vessels, and intraabdominal bleeding from decidualized deep infiltrating endometriosis (DIE) lesion have been rarely reported. Owing to the potential risk of rupture and resultant life-threatening complications, proper diagnosis and close monitoring of decidualized endometriotic lesion are very important despite its low relative risk. Till date, massive vaginal bleeding from decidualized rectovaginal DIE during pregnancy has not been in English literatures. Here, we present the first case of spontaneous massive vaginal bleeding due to decidualized rectovaginal DIE that occurred in the late third trimester of pregnancy.

• Journal of Chest Surgery
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• v.12 no.4
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• pp.361-364
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• 1979

The first Mitral Commissurotomy was performed for tight mitral stenosis on March 1957. The patient was at that time 22-year-old male, student. The longest follow 9p for 22 years and 8 months has been obtained. During the follow up period, late deterioration due to restenosis developed 4 years after initial good result and reoperation was succeeded by transventricular Mitral Valvotomy with Tubb`s ilator on April 1964. The possible cause of restenosis was attributed to recurrent rheumatic activity. After more than 13 years long-good life following 2nd operation, Endocarditis such as episode of high fever & chill intermittently followed by mild fever and night sweat, I t. tibial artery embolization and rupture of aortic cusp. At present, patient complained of no subjective symptom, enjoying ordinary life {NYHA II]. Blood pressure has been 110/50-60 mmHg, trivial diastolic murmur at apex and moderate degree of mechanical murmur on diastole at Erb`s rea. Neither signs of RVH for mitral stenosis nor sign of LVH. ST-T change for aortic regurgitation appeared yet during last 2 yrs. The patient`s are for prevention of Rheumatic activity and development of endocarditis is important for obtaining the better long-term result.

• Proceedings of the KIEE Conference
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• 2000.11a
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• pp.265-268
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• 2000

In this study, a small punch creep (SP-Creep) test using miniaturized specimen has been described for the development of the new creep test method for high temperature structural components such as headers and tubes of boiler, turbine casing and rotor, and reactor vessel. The SP-Creep testing technique has been applied to 1Cr-0.5Mo steel used widely as boiler header material and the creep test temperature are varied at $550^{\circ}C{\sim}600^{\circ}C$. From the experimental results, e.g. SP-Creep curve behaviors, the creep rate in steady state and creep rupture life with test temperature and load, the load exponential value(n, m), the activation energy($Q_{spc}$), the Monkman-Grant relation and the creep life assessment equation etc., it can be summarized that the SP-Creep test may be a useful test method to evaluate the creep properties of the heat resisting material such as boiler header.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.23 no.11 s.170
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• pp.2022-2032
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• 1999

In recent years, the subject of remaining life assessment has drawn considerable attention in the power generation industry. In power generation systems a variety of structural components, such as steam pipes, turbine rotors, and superheater headers, typically operate at high temperatures and high pressures. Thus a life prediction methodology accounting for fracture and rupture is increasingly needed for these components. For accurate failure assessment, in addition to the single parameter such as K or J-integral used in traditional fracture mechanics, the second parameter like T-stress describing the constraint is needed. The most critical defects in such structures are generally found in the form of semi-elliptical surface cracks in the welded piping-joints. In this work, selecting the structures of surface-cracked plate and straight pipe, we first perform line-spring finite element modeling, and accompanying elastic-plastic finite element analyses. We then present a framework for including constraint effects (T-stress effects) in the R6 failure assessment diagram approach for fracture assessment.

• Journal of the Korean Wood Science and Technology
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• v.42 no.2
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• pp.130-137
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• 2014

Nondestructive evaluation (NDE) method by using a resonance frequency mode was carried out for ceramics made from particle boards with different phenol resin impregnation ratios (30, 40, 50, 60%) at carbonizing temperature of $800^{\circ}C$. The material for ceramics was Miscanthus sinensis var. purpurascens board. Dynamic modulus of elasticity increased with increasing impregnation ratio. There was a close relationship of dynamic modulus of elasticity and static bending modulus of elasticity to modulus of rupture (MOR). However, the result indicated that correlation coefficient is higher in dynamic modulus of elasticity to MOR than that in static modulus of elasticity to MOR. Therefore, the dynamic modulus of elasticity using resonance frequency by free vibration mode is more useful as a nondestructive evaluation method for predicting the MOR of ceramics made from Miscanthus sinensis var. purpurascens particle boards by different phenol resin impregnation ratios.