• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.111-118
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• 2003

I measured the movement range on the hinge articulator and the movement range in an oral. And then I studied to analyze the gap. I got wax records by the movement on the hinge articulator, the movement in an oral and the movement on the hand articulating. I measured the distance of the cusp tips that are close to the mesial direction and the distal direction, the buccal direction and the lingual direction then I compared gaps. As I saw results on data, I knew that the hinge articulator represented the range of mandibular movement restrictively. I could find the decisive contradiction that the sliding movement finished on the hinge articulator although it did not finish in an oral. If the sliding movement does not reappear exactly, it brings a fatal failure to the dental prosthesis. In addition it is impossible that the hinge articulator restores the movement in an oral because the lateral condyle inclination and the horizontal condyle inclination are fixed previously. Therefore dental prosthesisses were made by the hinge articulator, they will interfere with a mastication. I have obtained the following results; 1. The distance of sliding movement on the hinge articulator showed shorter than the distance of sliding movement in oral. This means the increase of cusp inclination of the dental prosthesis that was made on the hinge articulator. Therefore, when the lateral movement occurs in oral, there is a possibility to become the premature as the increase of cusp inclination. 2. The results that were impressed records in oral and impressed records on the hand articulating have many congruities. I think that the simple crown etc. that were made by the hand articulating method except the long span bridge and the free end case that can not measure the vertical dimension exactly can represent similarly the mandibular movement. 3. If we want to represent the mandibular movement similarly, we have to use the articulator that can adjust the horizontal condyle inclination and the lateral condyle inclination at least.

• Journal of Chest Surgery
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• v.12 no.3
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• pp.207-214
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• 1979

This 3-year-old girl was observed frequent exertional dyspnea and cyanosis at crying since birth. She was not premature baby and delivered at full term normally. On physical examination, she was underdeveloped-body weight 13.5 kg, height 99 cm.- and cyanotic. There was severe clubbing on fingers. There was grade II/VI ejection systolic murmur on left lateral border of the sternum. The preoperative examinations [EKG, echocardiogram, cardiac catheterization and biventriculogram] showed that complicated T.G.A. combined vena cava[S.D.D.]. Preoperatively, we decided the corrective surgery of Rastelli operation using a. pulmonary valved conduit. The operation was performed under total circulatory arrest using deep profound hypothermia combining with extracorporeal circulation. On operation, the anatomy of the heart showed that, 1. The subaortic conus was seen and subaortic muscles were hypertrophied. 2. The VSD[type II], behind the subaortic conus-about 1 cm. in diameter, was visible only through LV cavity and, 3. The pulmonary valve ring was hypoplastic and pulmonary valvular stenosis was seen also. The subpulmonic area [LV outflow tract] was obstructed with hypertrophied muscle and mitral valve. 4. Left superior vena cava was drained to RA via coronary sinus. 5. LAD coronary artery was originated from right coronary artery and ran anterior to the pulmonary artery. According to above anatomy, we performed the VSD closure with Teflon patch, and Mustard operation combined with LV-to-pulmonary artery bypass graft using the valve contained [Hancock 16 mm] conduit. Postoperatively, adequate blood pressure could be maintained under the state of using inotropic agent [epinephrine]. On the second postoperative day, the patient died of cardiac arrest due to low cardiac output syndrome, acute renal failure and pulmonary edema.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.11 no.1
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• pp.88-98
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• 2011

Lesch-Nyhan syndrome is a X-linked recessive disorder caused by a deficiency of the enzyme hypoxanthine-guanidine phosphoribosyltransferase (HPRT), enzyme to recycle purines. Case history: born induced vaginal delivery at 40 weeks complicated by premature membrane ruputure, body weight 2.820 gm. He showed failure to thrive showing severe protein aversion like milk products and pink daper. Developmental delay revealing rolling over at 10.5 month, followed by regression. Seizure at 2 months, His poor oral feeding was lifelong problem. Weak crying, spastic, choreoathetoid movement. Self mutilating behavior noted and diagnosed at age 3 years. No family history of consanguinity and neurological disorders. Method: Laboratory test, physical exam, imaging study and molecular. Clinical follow up Treat ment with allopurinol. Result: uric acid 10.5 mg/dL (N 3.5-7.9), APRT 151.1uM/ min/ml pro(25.7-101), HPRT 7.6 (N 233.5-701) and c.151C>T hemizygote (p,Arg51X). Abdominal sonogram showed staghorn calculi in both kidneys, brain MRI brain atrophy. Clinical follow up showed, seizure at 2 mo, developmental delay (head control and, rolling over at at 11mo, pointing body part at 2 yr 7 mo, eye hand coordination at 2 y 11mo,creeping at 3 y 7 mo, speaking words at 6 y 6 mo ),and developmental regression at 3 yr of age. Sleeping problem including insomnia and severe constipation. Self mutilating behavior (lip bite) started at 2.5 yr, neurologic sx including intermittent upward gaze accompanied by swallowing difficulty at 3 y 7 mo grand mal seizure at 4.5 yr and spastic extremity and trunchal hypotonia and choleoathetoid movement and ataxia at 6.5 yr. Scoliosis with severe spasticity at 9 yr 9 mo. Acute life threatening episode with irregular breathing at 9 yr and 9 mo, Emaciation and nephrolithiasis and recurrent pneumonia. Died suddenly at 10 yr 3 mo. Conclusion: life long feeding problem, chronic gut motility dysfunction, sleeping difficulty and progressing neurologic deterioration and nephrolithiasis despite normal serum uric acid maintence by allopurinol treatment.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.5
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• pp.537-542
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• 2011

The thermo-mechanical interaction between brake block and wheel tread during braking has been found to cause thermal crack on the wheel tread. Due to thermal expansion of the rim material, the thermal cracks will protrude from the wheel tread and be more exposed to wear during the wheel/block contact than the rest of the tread surface. The wheel rim is in residual compression stress when is new. After service running, the region in the tread has reversed to tension. This condition can lead to the formation and growth of thermal cracks in the rim which can ultimately lead to premature failure of wheel. In the present paper, the thermal cracks of railway wheel, one of severe damages on the wheel tread, were evaluated to understand the safety of railway wheel in running condition. The residual stresses for damaged wheel which are applied to tread brake are investigated. Mainly X-ray diffusion method is used. Under the condition of concurrent loading of continuous rolling contact with rails and cyclic frictional heat from brake blocks, the reduction of residual stress is found to correlate well with the thermal crack initiation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.108-113
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• 2018

Researches on strengthening and rehabilitation methods are being widely conducted due to the deterioration of existing concrete structures. Use of externally bonded Carbon Fiber Reinforced Polymers (CFRP) strips for the rehabilitation is a cost-effective and time-saving method. Generally, the CFRP layout for the shear strengthening was a uni-directional layout. Many researches have focused on the variables of the uni-directional CFRP layout such as the amount of material, angle, and spacing. Pilot tests indicated that the effective confinement of the concrete member can be provided with the bi-directional CFRP layout than the uni-directional layout. Therefore, the test was carried out after the uni- and bi-directional strengthening work using the same amount of CFRP material. CFRP anchors were installed to prevent unexpected premature CFRP delamination failure before reaching CFRP fracture strain. The effectiveness of the CFRP anchor and bi-directional CFRP layout for shear strengthening was verified based on the principal tensile strain contours.

• Journal of the Korean Society for Railway
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• v.12 no.3
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• pp.388-395
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• 2009

To investigate the flexural behavior of RC beams strengthened with glass fiber sheets, 1 control beam and 8 strengthened beams (4 NU-beams without U-shaped band and 4 U-beams with U-shaped band) are tested. The variables of experiment are composed of the number of glass fiber sheets and the existence of U-shaped band, etc. The maximum load was increased by 48% and 34%, and the flexural rigidity by 920% and 880% for NU-beam and U-beam, respectively, compared with those of the control beam. The ductility ratios were 1.43$\sim$2.60 for NU-beam and U-beam. The experimental results showed that the strengthening system with U-shaped band controls the premature debonding and provides a more ductile failure mode than the strengthening system without U-shaped band. It can be found from the load-deflection curves that as the number of fiber sheets is increased, the maximum strength and the flexural rigidity is increased. The experimental results are compared with the analytical results of nonlinear flexural behaviors for strengthened RC beam. The experimental and analytical results were well agreed.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.4
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• pp.213-220
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• 2020

In the present paper, implosion responses of two adjacent cylindrical tubes under external hydrostatic pressure were experimentally investigated. The cylinder models were fabricated of aluminium alloy 6061-T6 commercial tubes. In the experiment, a pair of two-cylinders were placed inside of a support frame in a medium-size pressure chamber, whose design pressure was 6.0MPa. The distance between the two-cylinders was 30 millimeter measured from outer shell at the mid-length. The implosion tests were performed with water and compressed nitrogen gas as the pressurizing media. The ambient static pressure of the chamber and local dynamic pressure near the two-imploded models were measured simultaneously. It was found that the energy released during an implosion from the first, weaker cylinder triggered the instability of the second, stronger cylinders. In other words, the resulting shock wave of the first implosive impact from the weaker cylinder could cause the premature failure of the neighboring stronger cylinders. The non-contact implosion phenomena from the two-cylindrical tube were clearly observed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.5
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• pp.483-491
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• 2008

The effectiveness of a new fiber-steel composite plate designed specifically to be used for strengthening of reinforced concrete members has been investigated. Twelve reinforced concrete beams were tested. Seven of the beams were strengthened with carbon fiber-steel composite plate(CSP), four of the beams were strengthened with glass fiber-steel composite plate(GSP), and one beam was used as a control specimen. The experimental results showed that new strengthening system controls the premature debonding and provides a more ductile failure mode than other conventional strengthening systems. The observed ductility ratios were $3.01\sim3.81$ and $3.55\sim4.95$ for strengthened beam with CSP and GSP, respectively. The maximum load was increased by 115% and 107% for strengthened beam with CSP and GSP, respectively, comparing with control beam. In addition, experimental and analytical results were well agreed.

• Journal of Korean Association for Spatial Structures
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• v.7 no.1 s.23
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• pp.79-85
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• 2007

Steel plate bonding method with epoxy is common applied to repair and strengthen RC structures, but Steel is apt to corrode quickly, hard to manufacture and heavy. To overcome these defects, it is carried out research on strengthening RC structures with FRP(Fibre Reinforced Polyrner/Plastic) FRP is generally used in the shape of Plate or Sheet, but it has weak point such as premature failure, difficult work. To cope with these problem, NSMR(Near Surface Mounted Reinforcement) which uses CFRP in the shape of Rod is proposed and carried out active research on strengthening effect of variables such as quantity, anchorage length and space of CFRP-Rod. Strengthening with CFRP-Rod is carried out under loading to some degree in fact, and so the amount of pre-loading is selected as variable in this research. The amount of pre-loading is chosen in proportion to nominal strength of non-strengthened specimen with CFRP-Rod.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.4
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• pp.322-329
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• 2016

Reconstruction of the maxillectomy with an obturator is to restore masticatory, swallowing, phonetic and esthetic problems. Stress created by lateral forces is minimized by the proper selection of an occlusal scheme, elimination of premature occlusal contacts, and wide distribution of supporting area. It should be considered that properly designed retainers reduce the stresses transmitted to the abutment while the obturator is in function. The following clinical report presents palatal obturator treatment with implant assisted removable partial denture (IARPD) design that restores normal function and esthetics in patients who experienced maxillectomy and dental implant failure.