• Korean Journal of Radiology
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• 제22권12호
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• pp.1974-1984
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• 2021

Objective: This study aimed to compare the efficacy between no-touch (NT) radiofrequency ablation (RFA) and conventional RFA using twin internally cooled wet (TICW) electrodes in the bipolar mode for the treatment of small hepatocellular carcinomas (HCC). Materials and Methods: In this single-center, two-arm, parallel-group, prospective randomized controlled study, we performed a 1:1 random allocation of eligible patients with HCCs to receive NT-RFA or conventional RFA between October 2016 and September 2018. The primary endpoint was the cumulative local tumor progression (LTP) rate after RFA. Secondary endpoints included technical conversion rates of NT-RFA, intrahepatic distance recurrence, extrahepatic metastasis, technical parameters, technical efficacy, and rates of complications. Cumulative LTP rates were analyzed using Kaplan-Meier analysis and the Cox proportional hazard regression model. Considering conversion cases from NT-RFA to conventional RFA, intention-to-treat and as-treated analyses were performed. Results: Enrolled patients were randomly assigned to the NT-RFA group (37 patients with 38 HCCs) or the conventional RFA group (36 patients with 38 HCCs). Among the NT-RFA group patients, conversion to conventional RFA occurred in four patients (10.8%, 4/37). According to intention-to-treat analysis, both 1- and 3-year cumulative LTP rates were 5.6%, in the NT-RFA group, and they were 11.8% and 21.3%, respectively, in the conventional RFA group (p = 0.073, log-rank). In the as-treated analysis, LTP rates at 1 year and 3 years were 0% and 0%, respectively, in the NT-RFA group sand 15.6% and 24.5%, respectively, in the conventional RFA group (p = 0.004, log-rank). In as-treated analysis using multivariable Cox regression analysis, RFA type was the only significant predictive factor for LTP (hazard ratio = 0.061 with conventional RFA as the reference, 95% confidence interval = 0.000-0.497; p = 0.004). There were no significant differences in the procedure characteristics between the two groups. No procedure-related deaths or major complications were observed. Conclusion: NT-RFA using TICW electrodes in bipolar mode demonstrated significantly lower cumulative LTP rates than conventional RFA for small HCCs, which warrants a larger study for further confirmation.

• 전자공학회논문지B
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• 제31B권8호
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• pp.87-98
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• 1994

Object-oriented analysis-synthesis coding subdivides each image of a sequence into moving objects and compensates the motion of each object. Thus it can reconstruct real motion better than conventional motion-compensated coding techniques at very-low-bit-rates. It uses a mapping parameter technique for estimating motion information of each object. Since a mapping parameter technique uses gradient operators it is sensitive to redundant details and noise. To accurately determine mapping parameters, we propose a new analysis method using integral projections for estimation of gradient values. Also to reconstruct correctly the local motion the proposed algorithm divides an image into segmented objects each of which having uniform motion information while the conventional one assumes a large object having the same motion information. Computer simulation results with several test sequences show that the proposed image analysis method in object-oriented analysis-synthesis coding shows better performance than the conventional one.

• International Journal of Aerospace System Engineering
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• 제2권2호
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• pp.54-57
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• 2015

The purpose of this paper is to provide the method of conventional stress analysis for a pressurized hydraulic cylinder with internal thread undercut. In the case of hydraulic cylinder with thread undercut, several loads and stresses occur during operating. So, the thread undercut can be most critical section has to be considered in detail for strength check. In this paper, the conventional stress analysis method at internal thread undercut of hydraulic cylinder based on Kowalski's formula is introduced. The method is verified by comparing to FEM analysis results using ANSYS.

• 한국생산제조학회지
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• 제21권2호
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• pp.221-224
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• 2012

This paper presents the strength safety of a hybrid alarm valve by a finite element analysis. The stress and strain of a conventional hybrid alarm valve are calculated for the given maximum test pressure of 2MPa. Especially, the FEM computed maximum stress of a conventional hybrid valve is only 18.6% of yield strength, 370MPa. This means that the conventional valve is designed with a thick thickness of a valve structure. But, new hybrid alarm valve model, which is developed by optimized design method in this study, shows more low level of 43% in maximum stress and strain compared with that of a conventional hybrid valve. These results may recommend the reduction of a weight and a dimension for an optimized hybrid alarm valve.

• Environmental Engineering Research
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• 제24권1호
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• pp.45-53
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• 2019

Water and soil properties in paddy fields subjected to organic and conventional farming were characterized over the rice cycle in South Korea. To achieve the goals of this study, we sampled and analyzed soil and water from 24 organic paddy plots and 11 conventional paddy plots in March, May, August, and October 2016. The results were analyzed using statistical analyses, including analysis of variance (ANOVA), cluster analysis, and principal component analysis. The ANOVA results showed that water content (WC), electrical conductivity (EC), organic matter (OM), and available phosphorus ($P_2O_5$) in soil varied significantly (p < 0.01) depending on the farming method. Higher OM, EC, and $P_2O_5$ of soil were observed in the conventional paddies than in the organic paddies. All soil properties, except pH and ammonium, depended on seasonal variation. Cluster analysis revealed that soil properties in May were distinctly separated from those in other seasons mainly due to basal fertilization. The principal component analysis distinguished the soil properties in different seasons, but such a distinction was not observed between the soil properties in organic and conventional paddies. Low contents of WC, OM, and total N were observed in March. High concentrations of nitrate and total P were observed in May, but these were low in August and October. The soils from October were also characterized by high concentrations of EC and $P_2O_5$. These results indicate that the sampling time for soil and water can significantly influence the evaluation of soil properties with different farming methods.

• 한국식품위생안전성학회지
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• 제38권4호
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• pp.264-272
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• 2023

본 연구에서는 재래생강과 중국종자생강 간의 증숙 시간별 총 페놀화합물, 총 플라보노이드, ABTS 및 DPPH 라디칼 소거능, gingerol, shogaol 함량을 비교 분석하였다. 총 플라보노이드와 총 페놀 화합물, ABTS radical 소거능의 경우 대체적으로 증숙 6시간에서 가장 높은 함량을 나타내다가 그 이상으로 증숙할수록 오히려 감소하는 경향을 보였으며, 생강 중에서는 재래생강인 WO-2가 가장 높게 나타났다. DPPH 라디칼 소거능은 증숙 시간별로 유의미한 차이가 없었다. 생강의 gingerol 함량은 대조군에서 WO-2가 1,351 mg/kg으로 가장 높은 함량을 나타냈다. 증숙 시간에 비례하여 gingerol의 함량은 감소하고, shogaol의 함량은 증가하였는데 증숙 8시간에서 WO-2가 생강 중에서도 가장 높았으며, 또한 종자별로도 재래생강이 중국 종자생강보다 shogaol 함량이 높은 것으로 나타났다. 본 연구결과 재래생강이 중국종자생강보다 기능성 함량이 높음을 확인하였으며 증숙 처리된 재래생강을 활용하여 다양한 식품을 개발할 수 있을 것으로 판단된다.

• The Journal of Asian Finance, Economics and Business
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• 제7권11호
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• pp.789-800
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• 2020

This study aims to examine the effect of perceived usefulness (PU), perceived ease of use (PEU), trust (TR), subjective norm (SN), and attitude (AT) on customer's Intention to Adopt Internet Banking (IAIB) at Islamic banks and conventional banks before and during the Covid-19 pandemic in Indonesia. The research model is based on the Theory of Planned Behavior (TPB) and the Technology Acceptance Model (TAM). This study involves 213 respondents for Islamic banks and 410 respondents for conventional banks from 25 provinces in Indonesia. Data was analyzed using partial least square (PLS) regression with the Structural Equation Model (SEM) method. The result of data analysis confirms several hypotheses taken from the literature. The results before the Covid-19 pandemic showed that AT and SN influence IAIB in Islamic banks. Whereas in conventional banks, AT, PU, SN, and TR influence IAIB. While during the Covid-19 pandemic, it shows that the AT, PU, IB, SN, and customer TR influence IAIB in Islamic banks and conventional banks. From the analysis, it was found that the PEU variable did not have a significant effect on the intention of customers of Islamic banks and conventional banks to use Internet banking.

• 제어로봇시스템학회논문지
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• 제5권4호
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• pp.419-426
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• 1999

A novel motion analysis system is presented in this paper. The proposed system is inspired by processing functions observed in the fly visual system, which detects changes in input light intensities, determines motion on both the local and the wide-field levels. The system has several differences from conventional motion analysis system. First, conventional systems usually focused on matching similar feature or optical flow, but neural network is applied in this system. Back propagation is used by learning method, and Tine Delay Neural Network (TDNN) is also used as analysis method. Second, while conventional systems usually limited on only two frames of sequence, the proposed system accept multiple frames of sequence. The experimental results showed a 94.7% correct rate with a speed of 71.47 milli seconds for real and synthetic images.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.215-217
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• 1997

In many conventional analysis of voltage stability the effect of load characteristics is ignored. But in the real system the load is composed of various components. Therefore if the load composition could be modeled then it will plays an important role in the analysis of static voltage stability. And also, if the system loss generally imposed to slack bus in the conventional load flow calculation is redistributed to each generator the accuracy of static voltage stability analysis can be improved. This paper presents the effect of load composition in the analysis of system stability as well the loss redistribution algorithm. And this paper will compare the result of conventional method with that of the proposed method.

• 한국군사과학기술학회지
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• 제10권3호
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• pp.148-153
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• 2007

In this paper, the evolutionary adaptive wavelet transform(EAWT) is applied to the scattering analysis of radar target. EAWT algorithm uses evolutionary programming for the time-frequency parameter extraction instead of FFT and the bisection search method used in the conventional adaptive wavelet transform(AWT). Therefore, the EAWT has a better performance than the conventional AWT. In the simulation using wire target(Airbus-like), the comparisons with the conventional AWT are presented to show the superiority of the EAWT algorithm in the analysis of scattering phenomenology. The EAWT can be effectively applied to the radar target recognition.