• 대한전기학회논문지:전력기술부문A
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• 제55권3호
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• pp.95-101
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• 2006

This paper proposes a modified current differential relay for $Y-{\Delta}$ transformer protection. The relay uses the same restraining current as a conventional relay, but the differential current is modified to compensate for the effects of the exciting current. A method to estimate the circulating component of the delta winding current is proposed. To cope with the remanent flux, before saturation, the core-loss current is calculated and used to modify the measured differential current. When the core then enters saturation, the initial value of the flux is obtained by inserting the modified differential current at the start of saturation into the magnetization cure. Thereafter, the core flux is then derived and used in conjunction with the magnetization curve to calculate the magnetizing current. A modified differential current is then derived that compensates for the core-loss and magnetizing currents. The performance of the proposed differential relay was compared against a conventional differential relay. Test results indicate that the modified relay remained stable during severe magnetic inrush and over-excitation, because the exciting current was successfully compensated. This paper concludes by implementing the relay on a hardware platform based on a digital signal processor. The relay does not require additional restraining signal and thus cause time delay of the relay.

• 한국전기전자재료학회논문지
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• 제20권6호
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• pp.487-490
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• 2007

In this paper, the formation and thermal stability characteristics of Ni silicide using Ni-V alloy on Boron cluster ($B_{18}H_{22}$) implanted bulk and SOI substrate were examined in comparison with pure Ni for nano-scale CMOSFET. The Ni silicide using Ni-V alloy on $B_{18}H_{22}$ implanted SOI substrate after high temperature post-silicidation annealing showed the lower sheet resistance, no agglomeration interface image and lower surface roughness than that using pure Ni. The thermal stability of Ni silicide was improved by using Ni-V alloy on $B_{18}H_{22}$ implanted SOI substrate.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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• pp.9-13
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• 2004

This paper proposes a modified current differential relay for Y-$\Delta$ transformer protection. The relay uses the same restraining current as a conventional relay, but the differential current is modified to compensate for the effects of the exciting current. A method to estimate the circulating component of the delta winding current is proposed. To cope with the remanent flux, before saturation, the core-loss current is calculated and used to modify the measured differential current. When the core then enters saturation, the initial value of the flux is obtained by inserting the modified differential current at the start of saturation into the magnetization cure. Thereafter, the core flux is then derived and used in conjunction with the magnetization curve to calculate the magnetizing current. A modified differential current is then derived that compensates for the core-loss and magnetizing currents. The performance of the proposed differential relay was compared against a conventional differential relay. Test results indicate that the modified relay remained stable during severe magnetic inrush and over-excitation because the exciting current was successfully compensated. The relay correctly discriminates magnetic inrush and over-excitation from an internal fault and is not affected by the level of remanent flux.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.262-262
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• 2010

반도체 제조공정 중 식각공정(Etching)은 웨이퍼표면으로부터 화학적, 물리적으로 불필요한 물질들을 선택적으로 제거하는 방법이다. 식각공정 중 하나인 플라즈마 식각(Plasma etching) 공정에서 오버식각(over-etching) 과언더식각(under-etching) 되는것을피하기위해서통계적인방법을기준으로식각종료점(endpoint)를 결정한다. 본 논문의 목표는 통계적인 분석방법을 이용하지 않고 실시간 식각 데이터(realtime etching data)를 사용해서 식각 종료점을 검출하는 것이다. 식각 데이터는 시계열 데이터(time-series data)이기 때문에 간단한 구조와 적은 계산량으로 빠른 수렴속도와 좋은 안정도를 가진 Radial Basis Function Neural Network's (RBF-NN) 를 이용하여 시계열 모델(time-series model)을 구현 하였다. 광학방사분광기(Optical Emission Spectroscopy: OES)로부터 나온 6개의 데이터 세트중에서 4개의 데이터 세트는 RBF-NN을 학습하는데 사용되고 2개의 데이터 세트는 모델의 성과를 시험해 보기 위하여 사용하였다. 학습을 위한 데이터들은 Matrix화 시켜서 목표값을 설정하여 학습시킨다. 실험한 결과 학습한 RBF-NN 모형이 식각 종료점(endpoint)를 정확하게 검출된다는 것을 보여준다.

• Advances in nano research
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• 제13권5호
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• pp.465-474
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• 2022

Based on the nonlocal strain gradient (NSG) theory and considering the influence of moment of inertia, the governing equations of motion of porous functionally graded (FG) nanoplates with four edges clamped are established; The Galerkin method is applied to eliminate the spatial variables of the partial differential equation, and the partial differential governing equation is transformed into an ordinary differential equation with time variables. By satisfying the boundary conditions and solving the characteristic equation, the dispersion relations of the porous FG strain gradient nanoplates with four edges fixed are obtained. It is found that when the wave number is very small, the influences of nonlocal parameters and strain gradient parameters on the dispersion relation is very small. However, when the wave number is large, it has a great influence on the group velocity and phase velocity. The nonlocal parameter represents the effect of stiffness softening, and the strain gradient parameter represents the effect of stiffness strengthening. In addition, we also study the influence of power law index parameter and porosity on guided wave propagation.

• 한국BIM학회 논문집
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• 제13권4호
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• pp.45-53
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• 2023

The educational benefits and potential of XR as a new medium are well recognized. However, there are still limitations in understanding the specific effects of XR compared to the more widely utilized representation of images on computer monitors. This study therefore aims to demonstrate the differences in effectiveness between the two technologies and to draw implications from a cognitive comparison of three-dimensional objects represented on a flat surface and virtually. The study was conducted a quantitative research method with an experiment involving two independent groups, and the results were tested using regression analysis. The results showed that for low-level, two-dimensional objects, the computer monitor method may be more effective, but above a certain level of complexity, the effectiveness of learning through the monitor tends to decrease rapidly. On the other hand, the group that used extended reality technology showed relatively high comprehension compared to the monitor group even as the complexity increased, and in particular, unlike the monitor group's rapidly decreasing comprehension level, the extended reality technology group showed a trend of decreasing comprehension with the level of complexity, suggesting the potential for compatibility and predictability in the use of technology.

• 대한한의진단학회지
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• 제11권1호
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• pp.1-24
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• 2007

Maek Kyoung(Mai Jing, 脈經) is the first chinese specialized book of diagnostics written by Wang Hee(Wang xi, 王熙) from Seo Jin(xi jin, 西晉). He assorted the contents with pulse and medical examination from Nae Kyoung(nei jing, 內經), Nan Kyoung(nan jing, 難經), Sang Han Ron(shang han lun, 傷寒論) and Jung Jang Kyoung(zhong cang jing, 中藏經). And united with his own research, he explains medical examination and the way of talking the pulse by classifying into entrance and class. Maek Kyoung(Mai Jing, 脈經) was imported Korea by Ji Chong(zhi cong, 知聰) AD 561, and he passed through Ko Ku Ryeo(gao gou li, 高句麗) with Nae Wei Jeon(nei wai dian, 內外典), Yak Seo(yao shu, 藥書), Myung Dang Do(ming tang tu, 明堂圖) and Maek Kyoung(Mai Jing, 脈經) to be naturalized in Japan. This treatise make a special study of the second volume of the Maek Kyoung. It consists of the four chapters: Pyoung Sam Kwan Eum Yang E Sip Sa Ki Maek Je II(平三關陰陽二十四氣脈第一), Pyoung In Young Sin Mun Ki Ku Jeon Hu Maek Je E(平人迎神門氣口前後脈第二), Pyoung Sam Kwan Byoung Hu Byoung Chi Eui Je Sam(平三關病侯幷治宜第三), and Pyoung Gi Kyoung Pal Maek Byoung Je Sa(平寄經八脈病第四). Bi Geup Choun Geum Yo Bang(備急千金要方) and Eui Hak Ip Mun(醫學入門) quoted from the contents in the second volume of Maek Kyoung, and Bin Ho Maek Hak(瀕湖脈學), Gi Kyoung Pal Maek Go(奇經八脈攷) and Maek Eo(脈語) extracted from contents in the second volume of the Maek Kyoung and requoted from this contents. Contents in the second volume of the Maek Kyoung have very valuable data like that, but the literature on this subject in the form of a treatise has not been yet in Korea. So I hope this study will be useful to develope Diagnostics by correcting translation and interpretation and fixing wrong translation.

• Asian Pacific Journal of Cancer Prevention
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• 제14권7호
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• pp.4261-4265
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• 2013

Increasing scientific evidence suggests that ribonucleotide reductase M1 (RRM1) may be a powerful predictor of survival in patients with pancreatic cancer treated with adjuvant gemcitabine-based chemotherapy after operative resection, but many existing studies have yielded inconclusive results. This meta-analysis aimed to assess the prognostic role of RRM1 in predicting survival in patients with pancreatic cancer treated with gemcitabine. An extensive literature search for relevant studies was conducted on PubMed, Embase, Web of Science, Cochrane Library, and CBM databases from their inception through May 1st, 2013. This meta-analysis was performed using the STATA 12.0 software and crude hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Eight clinical studies were included in this meta-analysis with a total of 665 pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy, including 373 patients in the high RRM1 expression group and 292 patients in the low RRM1 expression group. Our meta-analysis revealed that high RRM1 expression was associated with improved overall survival (OS) of pancreatic cancer patients (HR=1.56, 95%CI=0.95-2.17, P<0.001). High RRM1 expression also was linked to longer disease-free survival (DFS) than low RRM1 expression (HR=1.37, 95%CI=0.25-2.48, P=0.016). In conclusion, our meta-analysis suggests that high RRM1 expression may be associated with improved OS and DFS of pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy. Detection of RRM1 expression may be a promising biomarker for gemcitabine response and prognosis in pancreatic cancer patients.

• 원예과학기술지
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• 제33권4호
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• pp.535-541
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• 2015

'Taichung No. 2' is a new Asian pear cultivar developed in Taiwan with low chilling requirement; however, is likely to develop internal browning disorder under low temperature storage conditions. We investigated the impact of storage time on flesh browning disorder in pears harvested from 22 orchards in 2010 and 2011, and analyzed the levels of nutrients in different fruit parts such as the peel, flesh, and core. Calcium and potassium contents were higher in the flesh and peel, respectively, of more severely browned fruits, whereas a lower magnesium content was recorded in the peel and core of these fruits. Nitrogen and potassium contents in the peel, and calcium content in the flesh were positively correlated with browning disorder severity. By contrast, the magnesium content in the core was negatively correlated with browning disorder severity. However, the nutrient contents in fruits varied between the two sampling years considered. Only the K/Mg ratio was an effective predictor of the browning disorder severity and showed a positive linear correlation in the two years. We recommend that the K/Mg ratio should be lower than 10 to avoid severe browning disorder in pears.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.2399-2403
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• 2012

Objective: To compare expression level of serum tumor associated materials (TAM) with several conventional serum tumor biomarkers, eg., carcinoembryonic antigen (CEA), carbohydrate antigen19-9 (CA19-9), carbohydrate antigen 15-3 (CA15-3), alpha-fetoprotein(AFP), in selected solid tumors. Methods: Patients diagnosed histologically or cytologically with liver, breast, esophageal, gastric, colorectal or pancreatic cancers were enrolled into this study. After diagnosis, the level of TAM was determined by chemical colorimetry, and levels of conventional tumor markers was measured by chemiluminescence methods. Results: A total of 560 patients were enrolled into this study. No statistically significant difference was detected in TAM and the above mentioned tumor biomarkers in terms of their positivity and negativity ( P>0. 05). Conclusions: Detection of TAM in liver, breast, esophageal, gastric, colorectal, and pancreatic cancer patients demonstrates a good accordance with CEA, CA199, CA153, and AFP, thus suggesting that further study is warranted to verify whether TAM could be a surrogate for these conventional biomarkers.