• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1992년도 봄 학술발표회 논문집 깊은 기초의 연구와 실무(RESEARCH AND PRACTICE OF DEEP FOUNDATIONS)
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• pp.1-12
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• 1992

In recent years, active developments have taken place in Southeast Asia in various aspects of deep foundations. Some of these developments are reviewed in this Paper. These include techniques of behaviourial analysis such as Chin's Plot and Balasubramaniam's Pull-out Test. Also included are recent advances in small size piles, large bored piles and caisson foundations. The performance of and the experience gained in some of these foundations are highlighted.

• 한국전기전자재료학회논문지
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• 제13권12호
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• pp.977-982
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• 2000

Conventional transistors which have vertical structure show increased parasitic capacitance characteristics in accordance with the increase of non-active base area and collector area. These consequently have disadvantage for high speed switching performance. In this paper, a lateral structure transistor which has minimized parasitic capacitance by using SDB(Silicon Direct Bonding) wafer and oxide sidewall isolation utilizing silicon trench technology is presented. Its structural characteristics are designed by ATHENA(SUPREM4), the process simulator from SILVACO International, and its performance is proven by ATLAS, the device simulator from SILVACO International. The performance of the proposed lateral structure transistor is certified through the V$\_$CE/-I$\_$C/ characteristics curve, h$\_$FE/-I$\_$C/ characteristics, and GP-plot. Cutoff Frequency is 13.7㎓.

• 한국운동역학회지
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• 제20권2호
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• pp.183-189
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• 2010

The balanced performance of dominant and non-dominant leg is very important to Taekwondo sparring. The purpose of this study was to investigate whether elite Taekwondo athletes would have balanced biomechanical performance and intra-limb coordination in executing different types of Taekwondo kicks. Twelve athletes(more than 10 year practice experience) participated in this study and performed six basic kicks(i.e., the front, roundhouse, side, back, thrashing, and turning-back kick). Results indicated no statistical difference on response time, peak kicking velocity, single limb vertical jump height, and angle-angle plot between dominant leg and non-dominant leg(p>.05). In conclusion, elite Taekwondo athletes had equivalent ability between dominant leg and non-dominant leg in performing Taekwondo kicks. This might be an advantage to elite athletes for Taekwondo sparring because they could use both leg without any restriction.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.759-762
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• 2000

Present transistors which have vertical structure show increased parasitic capacitance characteristics in accordance with the increase of non-active base area and collector area, consequently have disadvantage for high speed switching performance. In this paper, a horizontal structure transistor which has minimized parasitic capacitance in virtue of SDB(Silicon Direct Bonding) wafer and oxide sidewall isolation utilizing silicon trench technology is presented. Its structural characteristics were designed by ATHENA(SUPREM4), the process simulator from SILVACO International, and its performance was proven by ATLAS, the device simulator from SILVACO International. The performance of the proposed horizontal structure transistor was certified through the VCE-lC characteristics curve, $h_{FE}$ -IC characteristics, and GP-plot.

• Journal of Biosystems Engineering
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• 제6권1호
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• pp.39-47
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• 1981

본(本) 연구(硏究)는 써레작업(作業) 후(後) 경과일수(經科日數)와 경심(耕深)에 따른 수도이앙기(水稻移秧機)의 작업상태(作業狀態)를 조사(調査)하여 적정포장조건(適正圃場條件)을 구명(究明)하고저 1980년(年) 4월(月)부터 1980년(年) 5월(月)까지 진주시(晋州市) 칠암동(七岩洞)에서 시험(試驗)을 실시(實施)하였으며 그 결과(結果)를 종합(綜合)하면 다음과 같다. 1. 소요동력(所要動力)은 써레(作業) 후(後) 경과일수(經過日數) 0.5일(日), 경심(耕深) 18cm구(區)에서 0.8ps로 가강 높게 나다났으며 엔진 탑재마력(搭載馬力)에 (2.5-3.5ps) 충분한 여유(餘裕)가 있어 이앙작업시(移秧作業時) 포장조건(圃場條件)에는 크게 지장(支障)이 없을 것으로 사료(思料)되었다. 2. 슬립율은 써레작업(作業) 후(後) 경과일수(經過日數) 0.5일(日), 경심(耕深) 18cm구(區)에서 42.5%로 가장 높았으나 써레작업(作業) 후(後) 경과일수(經過日數)와 경심(耕深)에 따라 점차(漸次) 낮아져 써레작업(作業) 후(後) 경과일수(經過日數) 2일(日), 경심(耕深) 12cm구(區)에서 슬립율이 26.3%로 가장 낮았다. 3. 주간간격(株間間隔)은 써레작업(作業) 후(後) 경과일수(經過日數) 2일(日), 심경(深耕) 12cm구(區)에서 13.9cm로 나타나 적정주간간격(適正株間間隔) 14cm에 가장 접근(接近)하였다. 4. 결주율(缺株率)은 써레작업(作業) 후(後) 경과일수(經過日數) 0.5일(日)에 이앙(移秧)한 구(區)에서는 인접(隣接)줄에 흙이 밀려 매몰묘(埋沒苗)가 많이 발생(發生)하였고 점차감소(漸次減少)하여 써레작업(作業) 후(後) 경과일수(經過日數) 2일(日)의 경심(耕深) 12cm구(區)에서 이앙작업시(移秧作業時) 결주율(缺株率) 1.5%로 가장 낮게 나타났다. 5. 식부심(稙付深)은 써레작업(作業) 후(後) 경과일수(經過日數) 2일(日), 경심(耕深) 15cm구(區)에서 2.95cm로 적정식부심(適正植付深) 3cm에 가장 접근(接近)하였다. 6. 식부자세(植付姿勢)는 써레작업(作業) 후(後) 경과일수(經過日數) 2일(日), 경심(耕深) 12cm구(區)에서 $89^{\circ}$로 적정식부심자세(適正植付深姿勢) $90^{\circ}$에 가장 접근(接近)하였다. 전체적(全體的)으로 식부자세(植付姿勢)는 80% 이상(以上) 바르게 심어진 상태(狀態)이므로 생육(生育)에는 크게 지장(支障)이 없을 것으로 사료(思料)되었다. 7. 식진성(植進成)은 써레작업(作業) 후(後) 경과일수(經過日數) 2일(日). 경심(耕深) 12cm구(區)에서 이탈거리(離脫距離)가 적게 나타나 직진상태(直進狀態)가 양호(良好)였다. 8. 이상(以上)의 시험결과(試驗結果)를 종합(綜合)하면 써레작업(作業) 후(後) 경과일수(經過日數) 2일(日) 경심(耕深) 12cm구(區)에서 이앙작업(移秧作業)을 실시(實施)하는 것이 바람직하다고 본다.

• 한국정밀공학회지
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• 제18권8호
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• pp.96-106
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• 2001

As the drilling depth increases, the cutting torque increases and fluctuates, which can lead to the machine tool vibration, severe tool wear, and catastrophic tool breakage. Hence, cutting torque control is very important to improve productivity in drilling. In this paper, a PID controller was designed to control the drilling torque. The plant including the feed drive system, cutting process and spindle drive system was modeled for controller design. The Ziegler-Nichols method was used to determine the controller gain and control action times and the root locus plot was used to tune the controller gain for a certain cutting condition. Also, suggested was a simple method to obtain the tuned controller gain for an arbitrary cutting condition not using the Ziegler-Nichols method and the root locus plot. The performance of the designed controller and the effect of controller gain tuning were verified from experiments.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.106-108
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• 2008

This paper deals with the design for speed controller to drive PMSM by matrix converter without DC-link circuit as the power conversion system of AC servo motor drive. To design the speed controller of PMSM drive, the closed-loop transfer function of speed controller is calculated and then the frequency-domain response characteristics are analyzed by bode plot using Matlab. Based on the results by bode plot, the speed control gains are determined. As the real effects of controller designed in the frequency-domain display in the time-domain, the performance of speed controller is confirmed by the step response of speed controller. The design examples are shown and its validity of the design method mentioned in the paper is verified through PSIM simulation.

• 한국전기전자재료학회논문지
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• 제22권6호
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• pp.466-468
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• 2009

The metal-insulator-silicon (MIS) capacitors with $SiO_2$ and high-k dielectrics ($HfO_2$, $Al_2O_3$) were fabricated, and the current-voltage characteristics were investigated. Especially, an effective barrier height between metal gate and dielectric was extracted by using Fowler-Nordheim (FN) plot and Direct Tunneling (DT) plot of quantum mechanical(QM) modeling. The calculated barrier heights of thermal $SiO_2$, ALD $SiO_2$, $HfO_2$ and $Al_2O_3$ are 3.35 eV, 0.6 eV, 1.75 eV, and 2.65 eV, respectively. Therefore, the performance of non-volatile memory devices can be improved by using engineered tunnel barrier which is considered effective barrier height of high-k materials.

• Journal of Information Processing Systems
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• 제18권3호
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• pp.302-310
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• 2022

Efficient use of limited blood products is becoming very important in terms of socioeconomic status and patient recovery. To predict the appropriateness of patient-specific transfusions for the intensive care unit (ICU) patients who require real-time monitoring, we evaluated a model to predict the possibility of transfusion dynamically by using the Medical Information Mart for Intensive Care III (MIMIC-III), an ICU admission record at Harvard Medical School. In this study, we developed an explainable machine learning to predict the possibility of red blood cell transfusion for major medical diseases in the ICU. Target disease groups that received packed red blood cell transfusions at high frequency were selected and 16,222 patients were finally extracted. The prediction model achieved an area under the ROC curve of 0.9070 and an F1-score of 0.8166 (LightGBM). To explain the performance of the machine learning model, feature importance analysis and a partial dependence plot were used. The results of our study can be used as basic data for recommendations related to the adequacy of blood transfusions and are expected to ultimately contribute to the recovery of patients and prevention of excessive consumption of blood products.

• Korean Journal of Radiology
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• 제22권10호
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• pp.1697-1707
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• 2021

The recent introduction of various high-dimensional modeling methods, such as radiomics and deep learning, has created a much greater diversity in modeling approaches for survival prediction (or, more generally, time-to-event prediction). The newness of the recent modeling approaches and unfamiliarity with the model outputs may confuse some researchers and practitioners about the evaluation of the performance of such models. Methodological literacy to critically appraise the performance evaluation of the models and, ideally, the ability to conduct such an evaluation would be needed for those who want to develop models or apply them in practice. This article intends to provide intuitive, conceptual, and practical explanations of the statistical methods for evaluating the performance of survival prediction models with minimal usage of mathematical descriptions. It covers from conventional to deep learning methods, and emphasis has been placed on recent modeling approaches. This review article includes straightforward explanations of C indices (Harrell's C index, etc.), time-dependent receiver operating characteristic curve analysis, calibration plot, other methods for evaluating the calibration performance, and Brier score.