• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.436-439
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• 1995

In this paper we present a method to construct fuzzy model with multi-dimension input membership function, which can construct fuzzy inference system on one node of the network directly. This method comes from a common framework called Universal Learning Network (ULN). The fuzzy model under the framework of ULN is called Universal Learning Network-based Fuzzy Inference System (ULNFIS), which possesses certain advantages over other networks such as neural network. We also introduce how to imitate a real system with ULN and a control scheme using ULNFIS.

• Clinical and Experimental Pediatrics
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• v.50 no.10
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• pp.965-969
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• 2007

Purpose : Measurement of antistreptolysin O (ASO) is often necessary to confirm a clinical diagnosis of recent streptococcal infection, especially in patients suspected of rheumatic fever and acute glomerulonephritis. Standard normal ranges for ASO should be established locally for each age group. We analyzed ASO to determine the upper limit of normal (ULN) ASO in children in the Gyeonggi-Incheon area. Methods : ASO in normal individual concentrations were measured quantitatively by nephelometry on sera from 753 children (Male : 381, Female : 372). ULN were determined by separating the upper 20% from the lower 80% of the group (80 percentile). Results : The mean ASO concentration calculated in a total cases was $149.9{\pm}7.2IU/mL$. The ASO concentration in neonates was $83.4{\pm}10.7IU/mL$, and lowest in the 1 year of age group, $26.7{\pm}6.6IU/mL$, and increased to $318.0{\pm}33.2IU/mL$ gradually in the 9 years of age group. Thereafter, ASO concentration decreased. The ULN for neonates was 122 IU/mL, for 0-3 years, 40 IU/mL; for 4-6 years, 113 IU/ mL; for 7-9 years, 489 IU/mL; for 10-19 years, 433 IU/mL; for 20-29 years, 122 IU/mL. Conclusion : The age-specific ULN for children in the Gyeonggi-Incheon area were determined. The distribution of ASO concentration according to age groups was different from previous reports. These results should be of clinical value to physicians to interprete the ASO results of their patients.

• Toxicological Research
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• v.33 no.4
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• pp.343-350
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• 2017

Lamivudine belongs to the set of antiviral agents effective against hepatitis B virus infection. Given case reports on liver injuries after certain antiviral agent treatments, this study examined the effects of lamivudine on alanine aminotransferase (ALT) and total bilirubin (TB) using a medical system database. A total of 1,321 patients taking lamivudine alone or with others were evaluated using laboratory hits in an electronic medical system at Seoul National University Hospital from 2005 through 2011. The patients were grouped according to prior ALT results: G#1, ALT < 40 IU/L; G#2, 40 IU/L ${\leq}$ ALT < 120 IU/L; G#3, 120 IU/L ${\leq}$ ALT < 240 IU/L; and G#4, ALT ${\geq}$ 240 IU/L. In G#1 and G#2 patients, lamivudine or adefovir treatment decreased ALT and TB compared to prior values. In G#3 and G#4 patients with three times the upper limit of normal (ULN) ${\leq}$ ALT < 15 times the ULN, both ALT and TB were decreased after treatment with lamivudine alone, or adefovir following lamivudine therapy, indicating that lamivudine therapy ameliorated liver functions. However, in G#4 patients who experienced severely advanced hepatitis (ALT ${\geq}$ 15 times the ULN, or ${\geq}$ 600 IU/L), lamivudine augmented TBmax ($6.3{\rightarrow}13.3mg/dL$) despite a slight improvement in ALT ($839{\rightarrow}783IU/L$), indicative of exacerbation of bilirubinemia. Patients who used adefovir after lamivudine also showed a high incidence of hyperbilirubinemia when they experienced severely advanced hepatitis. Treatment with adefovir alone did not show the effect. In conclusion, lamivudine may increase the risk of hyperbilirubinemia in patients with severely advanced hepatitis, implying that caution should be exercised when using lamivudine therapy in certain patient populations.

• Journal of Gastric Cancer
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• v.21 no.1
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• pp.74-83
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• 2021

Purpose: No consensus exists on whether to preserve or ligate an aberrant left hepatic artery (ALHA), which is the most commonly encountered hepatic arterial variation during gastric surgery. Therefore, we aimed to evaluate the clinical effects of ALHA ligation by analyzing the perioperative outcomes. Materials and Methods: We retrospectively reviewed the data of 5,310 patients who underwent subtotal/total gastrectomy for gastric cancer. Patients in whom the ALHA was ligated (n=486) were categorized into 2 groups according to peak aspartate aminotransferase (AST) or alanine aminotransferase (ALT) levels: moderate-to-severe (MS) elevation (≥5 times the upper limit of normal [ULN]; MS group, n=42) and no-to-mild (NM) elevation (<5 times the ULN; NM group, n=444). The groups were matched 1:3 using propensity score-matching analysis to minimize confounding factors that can affect the perioperative outcomes. Results: The mean operation time (P=0.646) and blood loss amount (P=0.937) were similar between the 2 groups. The length of hospital stay was longer in the MS group (13.0 vs. 7.8 days, P=0.022). No postoperative mortality occurred. The incidence of grade ≥ IIIa postoperative complications (19.0% vs. 5.1%, P=0.001), especially pulmonary complications (11.9% vs. 2.5%, P=0.003), was significantly higher in the MS group. This group also showed a higher Comprehensive Complication Index (29.0 vs. 13.9, P<0.001). Conclusions: Among patients with a ligated ALHA, those with peak AST/ALT ≥5 times the ULN showed worse perioperative outcomes in terms of hospital stay and severity of complications. More precise perioperative decision-making tools are needed to better determine whether to preserve or ligate an ALHA.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.28 no.3
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• pp.283-290
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• 2024

Hepatic compartment syndrome (HCS) is a rare but life-threatening entity that consists of a decreased portal flow due to intraparenchymal hypertension secondary to subcapsular liver hematoma. Lethal liver failure can be observed. We report three cases, and review the literature. A 54-year-old male was admitted for extensive hepatic subcapsular hematoma after blunt abdominal trauma. Initially, he underwent embolization of the hepatic artery's right branch, after which he presented clinical deterioration, major cytolysis (310 times the upper limit of normal [ULN]), and liver failure with a prothrombin time (PT) at 31.0%. A 56-year-old male underwent liver transplantation for acute alcoholic hepatitis. On postoperative day 2, he presented a hemorrhagic shock associated with deterioration of liver function (cytolysis 21 ULN, PT 39.0%) due to extensive hepatic subcapsular hematoma. A 59-year-old male presented a hepatic subcapsular hematoma five days after a cholecystectomy, revealed by abdominal pain with liver dysfunction (cytolysis 10 ULN, PT 63.0%). All patients ultimately underwent urgent surgery for liver capsule excision, hematoma evacuation, and liver packing, if needed. The international literature was screened for this entity. These three patients' outcomes were favorable, and all were alive at postoperative day 90. The literature review found 15 reported cases. HCS can occur after any direct or indirect liver trauma. Surgical decompression is the main treatment, and there is probably no place for arterial embolization, which may increase the risk of liver necrosis. A 13.3% mortality rate is reported. HCS is a rare complication of subcapsular liver hematoma that compresses the liver parenchyma, and leads to liver failure. Urgent surgical decompression is needed.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.183-186
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• 1995

A method is presented for optimization of Universal Learning Networks (ULN), where, together with gradient method, Simulated Annealing (SA) is employed to elude local minima. The effectiveness of the method is shown by its application to control of a crane system.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.1059-1063
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• 2012

Objective: Angiogenesis represents a key element in the pathogenesis of malignancy. There are no robust data on prognostic factors for overall survival (OS) in patients with metastatic colorectal cancer treated with vascular endothelial growth factor (VEGF)-targeted therapy. The present study was conducted to establish a prognostic model for patients using an oxaliplatin-based or irinotecan-based chemotherapy plus bevacizumab in metastatic colorectal cancer. Methods: Baseline characteristics and outcomes on 170 patients treated with FOLFIRI or XELOX plus anti-VEGF therapy-naive metastatic colorectal cancer were collected from three Turkey cancer centers. Cox proportional hazards regression was used to identify independent prognostic factors for OS. Results: The median OS for the whole cohort was 19 months (95% CI, 14.3 to 23.6 months). Three of the seven adverse prognostic factors according to the Anatolian Society of Medical Oncology (ASMO) were independent predictors of short survival: serum lactate dehydrogenase (LDH) greater than the upper limit of normal (ULN; p<0.001); neutrophils greater than the ULN (p<0.0014); and progression free survival (PFS) less than 6 months (p =0.001). Conclusion: Serum LDH and neutrophil levels were the main prognostic factors in predicting survival, followed by PFS. This model validates incorporation of components of the ASMO model into patient care and clinical trials that use VEGF-targeting agents.

• Clinical Endoscopy
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• v.55 no.1
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• pp.122-127
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• 2022

Background/Aims: Endoscopic ultrasonography (EUS) is warranted when cross-sectional imaging demonstrates common bile duct (CBD) dilatation without identifiable causes. This study aimed to assess the diagnostic performance of EUS in CBD dilatation of unknown etiology. Methods: Retrospective review of patients with dilated CBD without definite causes undergoing EUS between 2012 and 2017. Results: A total of 131 patients were recruited. The mean age was 63.2±14.1 years. The most common manifestation was abnormal liver chemistry (85.5%). The mean CBD diameter was 12.2±4.1 mm. The area under the receiver operating characteristic curve (AUROC) of EUS-identified pathologies, including malignancy, choledocholithiasis, and benign biliary stricture (BBS), was 0.98 (95% confidence interval [CI], 0.95-1.00). The AUROC of EUS for detecting malignancy, choledocholithiasis, and BBS was 0.91 (95% CI, 0.85-0.97), 1.00 (95% CI, 1.00-1.00), and 0.93 (95% CI, 0.87-0.99), respectively. Male sex, alanine aminotransferase ≥3× the upper limit of normal (ULN), alkaline phosphatase ≥3× the ULN, and intrahepatic duct dilatation were predictors for pathological obstruction, with odds ratios of 5.46 (95%CI, 1.74-17.1), 5.02 (95% CI, 1.48-17.0), 4.63 (95% CI, 1.1-19.6), and 4.03 (95% CI, 1.37-11.8), respectively. Conclusions: EUS provides excellent diagnostic value in identifying the etiology of CBD dilatation detected by cross-sectional imaging.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.1
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• pp.67-75
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• 2010

Submarine and deep sea diving structures are generally designed based on their ultimate strength. Fatigue strength at welded joint must be also taken into account because working stress is increased due to the increasing of diving depth and using high yield steel. The pressure hulls of submarine are subjected to fluctuating compressive loading. But in addition to the calculated stresses, high residual tensile stresses at welded part have to be considered. The state of stress level of pressure hull is tensile at surface and compressive at deep diving depth. This paper presents the results of an experimental investigation on the crack initiation and growth at the weld toe of T welded joints of HY-100 steel plate under constant amplitude loading. It is also investigated the phenomenon of the fatigue failure and test methods. Fatigue tests have been using real scaled local structural models of full penetration T-welded joint, which is a part of the cylindrical shell structures reinforced by ring stiffeners. Several load ratios under constant amplitude loading are considered in the tests. Crack initiation and growth characteristics are examined based on the beach marks of the cracked section of the test specimens. A design stress-life curve including the design formula is suggested according to tested data.

• Journal of Yeungnam Medical Science
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• v.25 no.1
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• pp.31-40
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• 2008

Background/Aims : Entecavir is a synthetic nucleoside analogue, cyclopentyl guanine nucleoside, which has a potent antiviral effect and the least viral breakthrough in hepatitis B virus (HBV) replication. Entecavir has been available in Korea since 2007 but there are few reports on its effects. The aim of this study was to evaluate the virological response (VR) and biochemical response (BR) to entecavir in HBV patients at 3, 6 and 9 months after treatment with entecavir. Materials and Methods : Thirty-three chronic hepatitis B patients who took entecavir for at least 9 months were enrolled. We investigated VR and BR by retrospectively reviewing medical records. Patients who satisfied the following criteria were chosen: 1) initial alanine aminotransferase (ALT) levels = 1.5upper limit of normal (ULN) and 2) initial HBV DNA levels = $5\;log_{10}\;copies/ml$. We measured ALT levels every 3 months until month 9. HBV DNA was measured every 2 or 3 months by polymerase chain reaction (PCR) method. Results : Most patients taking entecavir showed good BR (ALT < 40 IU/L). The BR rates were 61%, 73% and 67% at months 3, 6 and 9, respectively. VR (HBV DNA < $5\;log_{10}\;copies/ml$ or 2 log lower than initial HBV DNA) rates were 82%, 91% and 91% at months 3, 6 and 9, respectively. Undetectable HBV DNA (HBV DNA < 4 log10 copies/ml) rates were 49%, 73% and 85% at months 3, 6 and 9, respectively. Two patients presented with virological breakthrough without adverse effects until month 9. Conclusions : Entecavir showed good BR and VR from month 3 and these effects continued through the 9-month observation period. This suggests that entecavir is also a good choice for the first line treatment of chronic hepatitis B (CHB). Further studies are needed to determine the long-term efficacy and drug resistance of entecavir in Korean CHB patients.