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A Performance Comparison of Super Resolution Model with Different Activation Functions (활성함수 변화에 따른 초해상화 모델 성능 비교)

  • Yoo, Youngjun;Kim, Daehee;Lee, Jaekoo
    • KIPS Transactions on Software and Data Engineering
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    • v.9 no.10
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    • pp.303-308
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    • 2020
  • The ReLU(Rectified Linear Unit) function has been dominantly used as a standard activation function in most deep artificial neural network models since it was proposed. Later, Leaky ReLU, Swish, and Mish activation functions were presented to replace ReLU, which showed improved performance over existing ReLU function in image classification task. Therefore, we recognized the need to experiment with whether performance improvements could be achieved by replacing the RELU with other activation functions in the super resolution task. In this paper, the performance was compared by changing the activation functions in EDSR model, which showed stable performance in the super resolution task. As a result, in experiments conducted with changing the activation function of EDSR, when the resolution was converted to double, the existing activation function, ReLU, showed similar or higher performance than the other activation functions used in the experiment. When the resolution was converted to four times, Leaky ReLU and Swish function showed slightly improved performance over ReLU. PSNR and SSIM, which can quantitatively evaluate the quality of images, were able to identify average performance improvements of 0.06%, 0.05% when using Leaky ReLU, and average performance improvements of 0.06% and 0.03% when using Swish. When the resolution is converted to eight times, the Mish function shows a slight average performance improvement over the ReLU. Using Mish, PSNR and SSIM were able to identify an average of 0.06% and 0.02% performance improvement over the RELU. In conclusion, Leaky ReLU and Swish showed improved performance compared to ReLU for super resolution that converts resolution four times and Mish showed improved performance compared to ReLU for super resolution that converts resolution eight times. In future study, we should conduct comparative experiments to replace activation functions with Leaky ReLU, Swish and Mish to improve performance in other super resolution models.

DETECTION OF EARLY PROXIMAL CARIES WITH LASER FLUORESCENCE (레이저 형광법을 이용한 인접면 우식증의 진단)

  • Seol, Jae-Heon;Oh, You-Hyang;Lee, Nan-Young;Lee, Sang-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.31 no.2
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    • pp.236-246
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    • 2004
  • Artificial carious lesions in various depths were observed with visual examination using light transillumination, bite-wing radiography, laser fluorescence, and dye-enhanced laser fluorescence to determine the reproducibility, correlation of each diagnostic method, diagnostic sensitivity and diagnostic specificity. And optical densities according to demineralized times were measured whether laser fluorescence could be used as a quantitative diagnostic method. The following results were obtained whether laser fluorescence could be used for diagnosis of initial proximal caries. 1. Tau-c values of visual examination was 0.08 which showed lowest reproducibility and those of bite-wing radiography, laser fluorescence, dye-enhanced laser fluorescence were 0.60, 0.48, and 0.64, respectively which showed relatively high reproducibility. 2. The correlation between demineralization time and each examination was the highest in dye-enhanced laser fluorescence$({\gamma}=0.51)$ followed by laser fluorescence$({\gamma}=0.43)$, bite-wing radiograph$({\gamma}=0.35)$, and visual examination$({\gamma}=0.33)$. Dye-enhanced laser fluorescence and laser fluorescence showed significant correlation with demineralization time. 3. The sensitivity of laser fluorescence and dye-enhanced laser fluorescence for diagnosing approximal caries based on bite-wing radiography were 67%, 100% and those of specificity were 57%, 11% which showed diagnostic specificity was relatively lower than sensitivity. 4. The difference in optical density(DFR) between sound teeth and carious lesions according to lesion depth was high with dye-enhanced laser fluorescence compared with laser fluorescence. DFR measured with laser fluorescence according to changes in lesion depth was statistically significant but was not statistically significant with dye-enhanced laser fluorescence. Based on these results, laser fluorescence and dye-enhanced laser fluorescence have comparable diagnostic power as bite-wing radiography in early diagnosis of proximal caries.

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COMPARISON OF MICROTENSILE BOND STRENGTH OF COMPOSITE RESTORATION TO ERODED ENAMEL BY SURFACE TREATMENT (접착제의 종류에 따른 침식치아에 대한 복합레진의 결합강도)

  • Lee, Soon-Young;Lee, Kyung-Ho;Noh, Hong-Seok;Jeong, Tae-Sung;Kim, Shin
    • Journal of the korean academy of Pediatric Dentistry
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    • v.38 no.4
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    • pp.348-354
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    • 2011
  • Composite resin has been widely used for eroded enamel. But, as there have been many reports about the differences in physicochemical characteristics of eroded enamel compared with sound enamel, an additional effort was thought necessary to obtain the optimal bond strength. As a possible answer, we came to think about the application of infiltrant resin which is known to have an excellent penetration capacity into enamel. This study was performed for the purpose of comparing the bond strength of composite restoration with or without infiltrant resin under adhesives on the artificially eroded enamel. 60 extracted sound maxillary primary incisors were selected and divided into group 1, 2, 3 according to the number of artificial erosion cycling for 5 minute duration in 1% citric acid of pH 3.2 at $37^{\circ}C$. And the labial surfaces were divided into 3 areas; group A, only resin adhesive was used, group I, only infiltrant resin, group IA, infiltrant resin followed by resin adhesive. Afterwards, every specimen was restored with composite resin. Microtensile bond strength was measured and failure modes were observed. The obtained results were as follows: 1. In comparing the bond strength by the degree of enamel erosion, it was revealed the highest bond strength in group 1, followed by group 2 and 3, showing the lowest bond strength in most eroded group(p<0.05). 2. In comparing the bond strength by surface treatment methods, group IA and I showed higher value than group A(p<0.05), with unsignificant difference between group I and IA(p>0.05). 3. In observation of failure mode, it was shown higher frequency of cohesive failure in order of 1-2-3 and IA-I-A. Conclusively, it was shown decreasing tendency of bond strength as the enamel is more eroded, and infiltrant resin was thought helpful to replace or add to the resin adhesive for optimal bonding with eroded enamel.

Identification of Feeding Stimulants for Juvenile Pacific Bluefin Tuna, Thunnus orientalis in Muscle Extract of Horse Mackerel, Trachurus japonicus (참다랑어(Thunnus orientalis) 치어에 있어서 전갱이(Trachrus japonicus) 근육 엑기스 중의 섭이촉진물질 검색)

  • Ji, Seung-Cheol;Takaoka, Osamu;Seoka, Manabu;Kohbara, Jun;Hosokawa, Hidetuyo;Shimeno, Sadao;Jeong, Gwan-Sik;Lee, Si-Woo;Takii, Kenji
    • Journal of Aquaculture
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    • v.20 no.1
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    • pp.19-25
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    • 2007
  • For establishing a basal diet for the Pacific bluefin tuna Thunnus orientalis (PBT), feeding stimulants were initially identified by omission test using the synthetic extract of horse mackerel, Trachurus japonicus. Four feeding trials were conducted using juvenile PBT weighing $9.0{\pm}0.91\;g$ (trial 1, 2 and 3) and $1.6{\pm}0.23\;g$ (trial 4), which were originated from an artificial seedling production. The fish fed the casein diet with each test solution were added at the ratio of 100 g casein diet to 100 g jack mackerel muscle. A complete synthetic extract of jack mackerel containing all 3 fractions, amino acid, nucleotide and organic nitrogenous base, exhibited a comparable feeding stimulant activity compared to that of natural extract. The omission of nucleotide or amino acid fraction showed lower feeding activity, but the omission of other nitrogenous fraction maintained a similar feeding stimulant activity compared to that of the synthetic extract (trial 1). Inosine-5' monophosphate $Na_2$ (IMP) was identified as a major constituent for maintaining feeding activity. The mixture of L-alanine, L-glutamic acid, L-histidine, L-lysine, taurine and IMP induced a similar feeding activity compared to that of the synthetic extract (trial 2 and 3). In trial 4, the highest feeding activity was finally obtained in the mixture of L-histidine, L-glutamine and IMP, followed by the synthetic extract, the mixture of L-lysine, L-alanine and IMP, IMP and the mixture of L-histidine, L-glutamic acid, L-lysine and L-alanine. These results revealed that the mixture of L-histidine, L-glutamic acid and IMP for the proper feeding stimulant of PBT in this study.

Comparison of Two Methods of Recruiting the Acutely Injured Lung (급성 폐손상에서 폐를 Recruit시키는 방법간의 비교 연구)

  • Suh, Gee-Young;Kang, Kyeong-Woo;Park, Sang-Joon;Kim, Ho-Choel;Young, Lim-Si;Chung, Man-Pyo;Han, Jeong-Ho;Kim, Ho-Joong;Kwon, O-Jung;Rhee, Chong-H.
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.4
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    • pp.500-512
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    • 2000
  • Background : To evaluate the efficacy of two methods of obtaining lung recruitment to reduce ventilator-induced lung injury(VILI). Methods : Fifteen New-Zealand white rabbits were ventilated in the pressure-controlled mode while maintaining constant tidal volume(10 ml/kg) and fixed respiration rate. Lung injury was induced by repeated saline lavage (PaO2<100 mmHg), and the pressure-volume curve was drawn to obtain Pflex. The animals were then randomly assigned to three groups and ventilated for 4 hours. In the control group(n=5), positive end-expiratory pressure(PEEP) less than that of Pflex by 3 mmHg was applied throughout the study. In the recruitment maneuver(RM) group(n=5), RM(CPAP of 22.5 mmHg, for 45 seconds) was performed every 15 minutes in addition to PEEP level less than Pflex by 3 mmHg This phrase is unclear. In the Pflex group, PEEP of Pflex was given without RM. Gas exchange, lung mechanics, and hemodynamics parameters as well as pathology were examined. Results : 1) Both the control and RM groups showed decreasing tendency in PaO2 with time. There was significantly decreased PaO2 at 4 hr compared to Ihr(p<0.05). But in the Pflex group, PaO2 did not decrease with time(p<0.05 vs other groups at 3, 4 hr). PaCO2 did not show significant difference among the three groups. 2) There was no significant difference in static compliance and plateau pressure. Mean blood pressure and heart rate also did not show any significant difference among the three groups. 3) The pathologic exam showed significantly less neutrophil infiltration in the Pflex group than in the control group(p<0.05). There was borderline significant difference in hyaline membrane score among the groups (p= 0.0532). Conclusion : Although recruitment maneuver of the injured lung may be important in decreasing VILI, it alone may not be sufficient to minimize VILI.

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Cultural Characteristics of Ectomycorrhizal Mushrooms

  • Jeon, Sung-Min;Ka, Kang-Hyeon
    • 한국균학회소식:학술대회논문집
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    • 2015.11a
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    • pp.16-16
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    • 2015
  • Ectomycorrhizal (ECM) mushrooms play a major role in plant growth promotion through symbiotic association with roots of forest trees. They also provide an economically important food resource to us and therefore they have been studied for their artificial cultivation for decades in Korea. We have secured bio-resources of ECM mushrooms from Korean forests and performed their physiological studies. To investigate the cultural characteristics, the fungi were cultured under different conditions (medium, temperature, pH of the medium, inorganic nitrogen source). More than 90% of total 160 strains grew on three solid media (potato dextrose agar, PDA; sabouraud dextrose agar, SDA; modified Melin-Norkrans medium, MMN). The rate of mycelial growth on malt extract agar (MEA) was lower than those of three media (PDA, SDA, MMN). None of the Tricholomataceae strains grew on MEA. Many strains of ECM mushrooms were able to grow at the temperature range of $15{\sim}25^{\circ}C$ on PDA, while they showed poor growth at $10^{\circ}C$ or $30^{\circ}C$. In particular, the growth rates of both Gomphaceae and Tricholomataceae were significantly lower at $10^{\circ}C$ than at $30^{\circ}C$. The optimal pH of many strains was pH 5.0 when they cultured in potato dextrose broth (PDB). Fifty-seven percent of tested strains grew well on medium containing ammonium source than nitrate source. Many strains of Tricholomataceae showed a notable growth on ammonium medium than nitrate medium. Twenty-three percent of strains preferred nitrate source than ammonium source for their mycelial growth. The production and activity of two enzymes (cellulase and laccase) by ECM fungi were also assayed on the enzyme screening media containing CMC or ABTS. Each strains exhibited different levels of enzymatic activities as well as enzyme production. The number of laccase-producing strains was less than that of cellulase-producing strains. We found that 77% of tested strains produced both cellulase and laccase, whereas 2% of strains did not produce any enzymes. The morphological characteristics of mycelial colony were also examined on four different solid media. Yellow was a dominant color in mycelial colony and followed by white and brown on all culture media. ECM mushrooms formed mycelial colonies with a single or multiple colors within a culture medium depending on the strains and culture media. The most common shape of mycelial colony was a circular form on all media tested. Other families except for Amanitaceae formed an irregular colony on MMN than PDA. All strains of Tricholomataceae did not form a filamentous colony on all media. The pigmentation of culture media by mycelial colonies was observed in more than 50% of strains tested on both PDA and SDA. The degree of pigmentation on PDA or SDA was higher than MMN and brown color was dominant than yellow color. The production of exudates from mycelial colony was higher on PDA than MMN. Brown exudates were mainly produced by many strains on PDA or SDA, whereas transparent exudates were mainly produced by strains on MMN. We observed the mycelial colonies with a single or multiple textures in just one culture plate. Wrinkled or uneven colony surfaces were remarkably observed in many strains on PDA or SDA, while an even colony surface was observed in many strains on MMN. Sixty percent of Tricholomaceae strains formed wrinkled surface on PDA. However, they did not form any wrinkle on MMN plate. Cottony texture was observed in mycelia colonies of many strains. Velvety texture was often observed in the mycelial colonies on SDA than PDA and accounted for 60% of Suillaceae strains on SDA.

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Ecological Characteristics and Vegetation Structure Analysis of Eurya Japonica Community -Focusing on Busan Metropolitan City- (사스레피나무 군락의 생태적 특성 및 식생구조 분석 -부산광역시를 중심으로-)

  • Jang, Jung-Eun;Lee, Sang-Cheol;Choi, Song-Hyun
    • Korean Journal of Environment and Ecology
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    • v.34 no.2
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    • pp.157-169
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    • 2020
  • The purpose of this study is to investigate the ecological characteristics and vegetation structures of Eurya japonica in Busan. As a result of the TWINSPAN and DCA analysis, 89 plots of 100㎡ each were divided into 3 communities: Quercus serrata-Pinus densiflora-E. japonica community, Pinus thunbergii-E. japonica community, and P. thunbergii-Camellia japonica community. Community I consisted of the Quercus serrata-Pinus densiflora-E. japonica which was mainly located in the high altitude inland. While Q. serrata and P. densiflora competed in the tree layer, the dominant species of the understory layer was E. japonica. Since Carpinus tschonoskii, one of the climax species, was distributed evenly from shrub to tree layers, it was likely that deciduous oak trees or Carpinus tschonoskii would become dominant species in community I. In community I, E. japonica was found in higher altitude than the other evergreen broad-leaved tree and was expected to maintain their tree vigor even if the vegetation structure is converted into the deciduous forest. Community II, the P. thunbergii-E. japonica community, was predicted to maintain its tree vigor unless there were unexpected disturbance factors. Community III, consisting of P. thunbergii-C. japonica and located in Dongbaek Island, was under artificial management. In community III, P. thunbergii was the only species in the tree layer, while C. japonica was predominant in the understory layer. E. japonica and various evergreen broad-leaved tree species were present in the understory layer and shrub layer, which were unmanaged areas. Therefore, it is expected that unless C. japonica is continuously managed, E. japonica is likely to become the dominant species. There were also various evergreen broad-leaved species, such as Machilus thunbergii and Pittosporum tobira, present in the shrub layer. If the temperature continues to rise, the habitat is expected to become evergreen broad-leaved forests in the future as P. thunbergii community declines. The result of Pearson's correlation coefficient analysis of E. japonica and species appearing in 89 plots showed that 9 species were had a statistically significant relationship (p<0.05). Four species, including P. tobira and Q. dentata, had a positive correlation. Five species had a negative correlation, and C. japonica, which had the same ecological position as E. japonica, showed the most negative correlation at -0.384.

Studies on Microbiological and Chemical Changes of Milk Treated by High Temperature (고온처리(高溫處理)에 의한 우유(牛乳)의 미생물(微生物) 및 화학적(化學的) 변화(變化)에 관한 연구(硏究))

  • Shin, Yong Kook;Kim, Jong Woo
    • Korean Journal of Agricultural Science
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    • v.13 no.2
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    • pp.198-209
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    • 1986
  • This study was conducted to find optimum heating temperature and time as milk was heated over a wide range of temperature and time combinations at $70{\sim}100^{\circ}C$ into $5^{\circ}C$ interval for 10, 15 and 20 second. The results obtained were summarized follows: 1. The effects of heat treatment on the bacteria by $75^{\circ}C/20s$, $80^{\circ}C/10s$ and $100^{\circ}C/20s$ were 99.56%, 99.52% and 99.92% respectively. 2. Sterilized rate of milk which was added Bacillus subtilis by $75^{\circ}C/20s$, $80^{\circ}C/10s$ and $100^{\circ}C/20s$ were 99.23%, 99.25% and 99.85% respectively. 3. The pH value fell in accordance with the increasing of heating temperature. 4. Content of protein, fat and lactose was not changed by heat treatment. 5. The content of total nitrogen was not changed. The content of casein nitrogen and non - protein nitrogen increased, but non - casein nitrogen reduced, according to heat trea ted of milk. 6. According to the increasing of heating and time, filter - passing nitrogen reduced. 7. The artificial digestibility was increased when milk was heated from $70^{\circ}C$ to $100^{\circ}C$ into $5^{\circ}C$ interval at 10, 15 and 20 second.

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Surgical Treatment of Thoracoabdominal Aortic Aneurysm (흉복부 대동맥류의 외과적 치료)

  • Ahn, Hyuk;Kim, Jun-Seok
    • Journal of Chest Surgery
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    • v.29 no.2
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    • pp.177-184
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    • 1996
  • Between 1987 and 1994, 21 patients were treated surgically for aortic aneurysm involving the thoracoabdominal aorta. There were 11 males and 10 females, and their age ranged from 20 to 67 years old and mean age was 41.5 years. Many complained of back pain, chest pain or discomfort, and flank pain, but three patients were asymptomatic. 15 patients had chronic dissection (71.4%) and 6 had nondissecting fusiform or saccular aneurysm(28.5%), and of those 15 patients with chronic dissection, 6(28.5%) had atherosclerosis assniated with hypertension, 5 (23.8%) were Martian syndrome, and 2 (9.5%) were associated with pregnancy. The diameter of an aneurysm ranged from 6cm to 12cm, and their extent was classified as type I in 7(33.3%), type II in 8(38.1%), type III in 3(14.3%), and type IV in 3(14.3%) patients based on Crawford classification for TAA . Diseased aorta was replaced with artificial vascular graft in all but one patient. In whom the aortic tear site due to pseudoaneurysm was closed by primary suture. For the spinal cord protection during the operation, we used partial cardiopulmonary bypass (FV-FA or PA-FA bypass) in 12 patients (57.1%), Biopump (LA-FA bypass) in 4(19.0%), total circulartory arrest and CPB in 2 (9.5%), Gott's heparinized shunt in 1(4.7%), and simple aortic cross clamping in 2 (9.5%). The most common complication after the operation was hoarseness due to unilateral vocal cord palsy which onured in 5 patients (23.8%), and the next common complication was wound infection in 4 patients(19.0%), paraplegia in 2 patients (9.5%), chylothorax in 1 patient(4.7%). The hospital mortality rate was 9.5% (2deaths), and there was no late death. Our experience shows that the graft replacement of TAAA had reasonable rate of mortality, low rate of serious complication, and provided good post operative state of the pati nts, and since the thoracoabdominal aortic operation is not a high risky procedure anymore, we recommend a radical operation for the indicated patients.

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The Long-term Clinical Result of St. Jude Mechanical Valve Replacement (St. Jude 기계판막 치환술의 장기 임상성적)

  • 배윤숙;정성철;김우식;정승혁;유환국;이정호;김병열
    • Journal of Chest Surgery
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    • v.36 no.5
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    • pp.321-328
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    • 2003
  • Background: The St. Jude Medical prosthesis is one of the popularly used artificial prosthesis, therefore the National Medical Center reports the long-term clinical results of patients who underwent prosthetic valve replacement with St. Jude medical valve for 18 years. Material and Method: Between January, 1984 and June, 2002, a series of 163 consecutive patients who had Implanted St. Jude prosthesis at the National Medical Center were reviewed. Mean age was 42.9$\pm$15.1 years and male to female ratio was 69:94. The operative procedure comprised of 87 MVR, 30 AVR, 45 DVR, and 1 TVR. The reoperative procedure comprised of 21 MVR, 2 AVR, and 14 DVR. Follow-up rate was 96.9%, and cumulative follow-up was 823.8 patient-years. Result: Early mortality rate was 7.9% (13 patients), late mortality rate was 8.7% (13 patients) and late mortality due to valve related complication was 47% (7 patients). Actual survival rate at 10 and 18 years were 91.7$\pm$2.1% and 91.0$\pm$1.9%. Linearized Incidence was as follows: thromboembolism, 1.09%/ patient-year; anticoagulant related hemorrhage, 0.36%/patient-year; valve thrombosis, 0.24%/patient-year; paravalvular leakage, 0.12%/patient-year; and prosthetic bacterial endocarditis, 0.12%/patient-year linearized incidence of over all valve related complication was 1.94%/patient-year. Freedom from valve related complication at 10 and 18 years were 89.1$\pm$3.3% and 88.4$\pm$3.9%. Freedom from valve related death at 10 and 18 years were 95.1$\pm$1.2% and 95.1$\pm$1.0%. Valve related complication was related the age of patient, especially anticoagulant related hemorrhage was more common in patients over 60 years of age. Valve related complication, death were higher in DVR than AVR or MVR, and valve related death was higher in reoperation. There was no relationship between valve related complication or death and implant valve of size. Conclusion: The long-term clinical results of patients implanted with St. Jude Mechanical prosthesis was quite satisfactory with a low incidence of valve related complication and mortality.