• Imaging Science in Dentistry
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• v.30 no.4
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• pp.243-248
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• 2000

Purpose: The aim of this study was to determine the relative radiopacities of cavity lining materials (Resin-modified Glass Ionomer cement, Compomer and Plowable resin) for posterior composite resin restoration. Material & Methods: Resin-modified glass ionomer cement (Fuji II LC, Vitrebond/sup TM/), Compomers (Dyract /sup (R)/ Compoglass, F2,000, Dyract/sup (R)/ flow Compoglass Flow) and Flowable resins (Tetric/sup (R)/ flow, Aeliteflo/sup TM/ Revolution/sup TM/) were used. Five specimens of 5 mm in diameter and 2 mm thick were fabricated with each material. Human molars were horizontally sectioned 2 mm thick to include both enamel and dentin. The radiopacities of enamel, dentin, cavity lining materials, aluminum step wedge were obtainded from conventional radiograph and NIH image program. Results: All the tested lining materials showed levels of radiopacity the same as or greater than that of dentin. All compomer tested (Dyract, Compoglass, F2,000, Dyract flow, Compoglass Flow) and Vitrebond/sup TM/, Tetric/sup (R)/ flow were more radiopaque than enamel. The radiopacities of Fuji II LC and Revolution/sup TM/ were between enamel and dentin and resin-modified glass ionomer cement, Compomer and Tetric/sup (R)/ flow were greater than those of Revolution/sup TM/, Aeliteflo/sup TM/ or dentin. The level of radiopacity of the tested materials was variable; those with low radiopacity should be avoided in class II restorations, where a clear determination of recurrent caries by the examining clinician could be compromised. Conclusion: Clinician should be able to distinguish these cavity lining materials radiographically from recurrent decay, voids, gaps, or other defects that lead to clinical failure. Utilization of materials ranked more radiopaque than enamel would enable clinicians to distinguish the lining material from tooth structure.

• Geotechnical Engineering
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• v.5 no.1
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• pp.47-60
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• 1989

Lateral earth Pressure distributions due to the ,randy soil backfill behind the rigid vertical walls for three different wall movement modes are obtained by the elasto-plastic finite element analys of soil deformation, and these earth pressures are compared with both Rankine's and Dubrova's active earth pressures. Thereby, the effects of the magnitude and the mode of wall displacement on the earth pressure distribution are investigated. Three different modes of wall movement considered in this study are the rotation about bottom, the rotation about top and the translation. For the case of the wall rotation about top, the earth pressure distribution is shown as a reverse S-curve-shaped distribution due to the arching effect. Consequently, the point of application of the lateral thrust is much higher than one-third of the wall height from the base. And, comparing the other modes of wall movement, the magnitude and the point of appliestion of the lateral thrust for the wall rotation about top are larger and higher, respectively. The wedge-shaped plastic zone in the backfill at active failure is developed only for the mode of wall rotation about bottom. The lateral earth pressure distributions on the walls with inclined backfill of several different slopes are shown for the mode of wall rotation about bottom.

• Biomolecules & Therapeutics
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• v.6 no.2
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• pp.199-203
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• 1998

Acute hemodynamic effects of CJ-18513, a non-peptide angiotensin IIreceptor antagonist, were examined in mongrel dogs treated with high frequency ventricular pacing for one week. Rapid ventricular pacing reduced mean blood pressure (mBP), Lvdp/dt and cardiac output (CO), and increased the left ventricular end-diastolic pressure (LVEDP) and pulmonary capillary wedge pressure (PCWP). Continuous infusion of CJ-10513 at doses of 10 and 20$\mu$g/kg/min, respectively, for 30 minutes reduced mBP, LVEDP and myocardial oxygen consumption rate (MVO,) and shifted the cardiac function curve (CO-LVEDP ourve) to the left in this dog model. In conclusion, CJ-10513 decreased the preload and afterload and increased the cardiac function in dogs with pacing-induced heart failure.

• Journal of Korean Neurosurgical Society
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• v.56 no.3
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• pp.230-236
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• 2014

Objective : The technique of short segment pedicle screw fixation (SSPSF) has been widely used for stabilization in thoracolumbar burst fractures (TLBFs), but some studies reported high rate of kyphosis recurrence or hardware failure. This study was to evaluate the results of SSPSF including fractured level and to find the risk factors concerned with the kyphosis recurrence in TLBFs. Methods : This study included 42 patients, including 25 males and 17 females, who underwent SSPSF for stabilization of TLBFs between January 2003 and December 2010. For radiologic assessments, Cobb angle (CA), vertebral wedge angle (VWA), vertebral body compression ratio (VBCR), and difference between VWA and Cobb angle (DbVC) were measured. The relationships between kyphosis recurrence and radiologic parameters or demographic features were investigated. Frankel classification and low back outcome score (LBOS) were used for assessment of clinical outcomes. Results : The mean follow-up period was 38.6 months. CA, VWA, and VBCR were improved after SSPSF, and these parameters were well maintained at the final follow-up with minimal degree of correction loss. Kyphosis recurrence showed a significant increase in patients with Denis burst type A, load-sharing classification (LSC) score >6 or DbVC >6 (p<0.05). There were no patients who worsened to clinical outcome, and there was no significant correlation between kyphosis recurrence and clinical outcome in this series. Conclusion : SSPSF including the fractured vertebra is an effective surgical method for restoration and maintenance of vertebral column stability in TLBFs. However, kyphosis recurrence was significantly associated with Denis burst type A fracture, LSC score >6, or DbVC >6.

• Composites Research
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• v.19 no.4
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• pp.15-22
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• 2006

One of the primary factors limiting the application of composite-metal adhesively bonded joints in structural design is the lack of a good evaluation tool for the interfacial strength to predict the load bearing capacity of boned joints. In this paper composite-steel adhesion strength is evaluated in terms of stress intensity factor and fracture toughness of the interface corner. The load bearing capacity of double lap joints, fabricated by co-cured bonding of composite-steel adherends has been determined using fracture mechanical analysis. Bi-material interface comer stress singularity and its order are presented. Finally stress intensities and fracture toughness of the wedge shape bi-material interface corner are determined. Double lap joint failure locus and its mixed mode crack propagation criterion on $K_1-K_{11}$ plane have been developed by tension tests with different bond lengths.

• Journal of Conservation Science
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• v.17 s.17
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• pp.83-94
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• 2005

Host rock or the standing sculptured Buddha in the Yongamsa temple is macular porphyritic biotite granite, which has gone through mechanical and chemical weathering. The rock around the Buddha statue is busily scattered with steep inclinations that are almost vertically discontinuous planes with the strikes of $N8^{\circ}E$. Especially the development of the joints that cross the major joints causes the structural instability of the rock. The rock of the Buddha statue is separated into several rock blocks because of many different discontinuity. Thus it is estimated that the bed rock has not only plane and toppling failure but also wedge failure in all the sides. Since the differential pressure is imposed on the body of the Buddha in the host rock, it is urgent to give a reinforce treatment of geotechnical engineering for the safe of its structural stability. Very contact area of joints have turned into soil, which promotes the growth of weeds and plant roots, then aggravates the mechanical weathering of the rock. Thus conservational treatments should also be considered to get rid of secondary contaminants and vegetation along the discontinuities and to prevent further damages.

• Geotechnical Engineering
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• v.14 no.6
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• pp.17-32
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• 1998

The Bakun hydroelectric project includes the construction of a hydroelectric power plant with an installed capacity of 2,520MW and a power transmission system connecting to the existing transmission networks in Sarawak and Western Malaysia, The power station will consist of a 210m height concrete faced rockfill dam. During the construction of the dam and the power facilities the Balui river has to be diverted by three diversion tunnels with a length of some 1,400m each. The inner diameter of the tunnels is 12m and the tunnel width is 16m at the portal area. This paper describes the stability analysis and design methods for the open cut rock slopes in the inlet and outlet area of the diversion tunnels. The geotechnical parameters employed in stability calculations were given as a function of four. defined Rock Mass Types (RMT) which were based on RMR system from Bieniawski. The stability calculations procedure of the rock slopes are divided into two stages. In the first stage, it is calculated for the stability of each 'global' slope without any rock support and shotcrete system. In the second stage, it is calculated for each 'local'slope stability with berms and supported with rock bolts and shotcrete. The monitoring instrumentation was performed continuously and some of the design modification was carried out in order to increase the safety of failed area based on the unforeseen geological risks during the open cut excavation.

• Journal of Chest Surgery
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• v.26 no.6
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• pp.475-482
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• 1993

90 patients[75 men and 15 women] with the thoracic disease underwent video-assisted thoracic surgery[VATS] during the period March 1992 to February 1993. The thoracic diseases were classified into two groups of spontaneous pneumothorax and general thoracic patients and they were 66 and 24, respectively.The mean size of the tumor resected was 4.3 $\pm$ 2.0 cm x 3.3 $\pm$ 1.1 cm x 2.7 $\pm$ 1.0 cm. The mean time of anesthesia and operation were 90.0 $\pm$ 19.9 min and 43.7 $\pm$ 13.1 min in spontaneous pneumothorax group and 123.3 $\pm$ 40.3 min and 62.8 $\pm$ 32.2 min in general thoracic group. The mean period of postoperative chest tube drainage and hospital stay were 5.0$\pm$ 5.5 days and 6.6 $\pm$ 7.4 days in spontaneous pneumothorax group and 3.5$\pm$ 1.6 days and 9.5 $\pm$ 6.1 days in general thoracic group. The indications of VATS were 71 pleural disease[78.9%: 66 spontaneous pneumothorax; 3 pleural effusions ; 1 pleural paragonimus westermanii cyst; 1 malignant pleural tumor with metastasis to the lung], 9 mediastinal disease[10.0%: 5 benign neurogenic tumor; 2 pericardial cyst; 1 benign cystic teratoma; 1 undifferentiated carcinoma], 8 pulmonary parenchymal disease[8.9%: 3 infectious disease ; 3 interstitial disease ; 2 malignant tumor ], and 2 traumatic cases of exploration and removal of hematoma[2.2%]. The applicated objectives of VATS were diagnostic[ 7 ], therapeutic[ 67 ] and both[ 16 ] and the performed procedures were pleurodesis[ 66 ], wedge resection of lung[ 59 ], parietal pleurectomy[ 11 ], removal of benign tumor[ 9 ], excision and/or biopsy of tumor[ 4 ], pleural biopsy and aspiration of pleural fluid[ 3 ] and exploration of hemothorax and removal of hematoma in traumatic 2 patients. The complication rate was 24.2%[ 16/66 ] in the spontaneous pneumothorax group and 8.3%[ 2/24 ] in the general thoracic group and so overally 20.0%[ 18/90 ]. The mortality within postoperative 30 days was 2.2%[ 2/90 ], including 1 acute renal failure and 1 respiratory failure due to rapid progression of pneumonia. The conversion rate to open thoracotomy during VATS was 5.6%[ 5/90 ], including 2 immediate postoperative massive air leakage, 1 giant bullae, 1 malignant pleural tumor with metastasis to lung and 1 pulmonary malignancy. The successful cure rate of VATS was 75.8%[ 50/66 ] in the spontaneous pneumothorax group and 76.5%[ 13/17 ] in the general thoracic group and the successful diagnostic rate was 100%[ 7/7 ]. In conclusion, although prospective trials should be progressed to define the precise role of VATS, the VATS carries a low morbidity and mortality and high diagnostic and therapeutic success rate and now can be effectively applicated to the surgical treatment of the extensive thoracic disease.

• Journal of Chest Surgery
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• v.25 no.1
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• pp.86-95
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• 1992

We have performed surgical operations for 184 primary lung carcinomas over a 10 year period from December, 1979 to December, 1990 at the department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine, Seoul, Korea. We have reviewed 77 cases confirmed to be dead in the post-operative follow-up period among 184 cases. There were 68 males and 9 females [M: F=7.56: 1], with 76.62% ranging between 50 to 70 years old There were 50 cases[64.94%] of squamous cell carcinoma, 15[19.48%] of adenocarcinoma, 4[5.19%] of large cell carcinoma, 4[5.19%] of mixed cell carcinoma 3 [3.90%] of small cell carcinoma % 1 case of bronchoalveolar cell carcinoma. There were 25 cases[32.47%] in stage I, 12 [15.58%] in stage II 32 [41.56%] in stage IIIa and 8 [10.39%] in stage IIIb according to the new international staging system for lung cancer. The operative methods were left pneumonectomy in 38 cases, right pneumonectomy in 21, bilobectomy in 5, lobectomy in 12, and wedge resection in one case.ase. There were 9 operative mortalities; one case by bleeding, 5 cases by respiratory failure, one case by bleeding & renal failure, one case by empyema thoracis with BPF and one case by brain metastases. The actuarial mean survival length was 14.636$\pm$18.188months overall and 16.441$\pm$18. 627months in 68 cases excluding 9 operative deaths. The actuarial mean survival length was 18.568$\pm$11.057 months in 43 squamous cell carcinomas, 14.385$\pm$11.057 months in 14 adenocarcinomas, 10.250$\pm$8.884months in 4 large cell carcinomas and 12.250$\pm$17.193months in 4 mixed cell carcinomas. The actuarial mean survival length was 14.051$\pm$16.963months in 59 pneumonectomy cases, 15.200$\pm$12.478 months in 5 bilobectomy cases, 18.417$\pm$26.026months in 12 lobectomy cases. The actuarial mean survival length was 28.952$\pm$25.738months in 22 stage I cases, 19. 455$\pm$16.723months in ll stage II cases, 8.633$\pm$6.584months in 29 stage IIIa cases and 6. 167$\pm$4.355months in 6 stage IIIb cases. The differences of actuarial mean survival length according to the stages were statistically significant [a=0.003]

• Journal of Conservation Science
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• v.26 no.2
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• pp.121-132
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• 2010

The Bukjiri Maaeyeoraejwasang (National Treasure No. 201) consists of two-mica granite in medium size, which was the simbol of power in the region of the Silla period. Magnetic susceptibility of the host rock was measured as 0.41(${\times}10^{-3}$ SI unit), which has the similar range with surrounding outcrop. The Buddha developed parallel discontinuous plane of NE to SW strike and damaged seriously by exfoliation, granular disintegration and brown discoloration as 41.5%, 16.7% and 40.0%, respectively. As a result of the ultrasonic velocity, which was relatively weak values as 1,629m/s (Buddha area) and 1,549m/s (surrounding outcrop), improved about 900m/s compared to last treatment. From the results of the evaluation for slope stability, identified the possibility of toppling failure in the Buddha, and planar and wedge failure in host rock. Therefore, we suggest for the safely conservation of the Buddha, continuance monitoring for understand behavior of discontinuity system of the surface, and necessitate foundation reinforcement method for the rock which has the danger of collapse.