http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Retinal Nerve Fiber Layer Thickness is Decreased in Patients With Hematologic Malignancy
Han, Jinu,Kim, Ji Hyun,Yoo, Hanna,Han, Sueng-Han,Hong, Samin,Seong, Gong Je,Kim, Chan Yun Wolters Kluwer Health, Inc. All rights reserved. 2016 Journal of glaucoma Vol.25 No.3
<P>Purpose: To investigate whether retinal nerve fiber layer (RNFL) thickness is decreased in patients with hematologic malignancy using optical coherence tomography (OCT). Patients and Methods: This prospective, observational cross-sectional study included 65 eyes from 34 patients with hematologic malignancy and 72 healthy control eyes. OCT-measured RNFL thickness parameters (average, 4 quadrants, and 12 clock-hour thickness) and RNFL defect in red-free photo were compared between patients with hematologic malignancy and controls. Results: Among average, quadrant, and clock-hour map, the only 11-o'clock RNFL in patients with hematologic malignancy was statistically thinner than in controls (P=0.021). The RNFL defect was detected in 21/65 (32.3%) patients with hematologic malignancy and in 5/72 (6.9%) controls (P<0.001). In patients with hematologic malignancy, the mean RNFL thickness was significantly lower in the severe and moderate anemia groups compared with the mild anemia group (P=0.011). In the generalized estimating equations model, the mean hemoglobin level was associated with RNFL thickness while correcting for inter-eye correlation, age, and refraction error (coefficient=3.685, P=0.006). Conclusions: The RNFL defect was frequently observed, and the RNFL was thinner in severe anemic patients with hematologic malignancy. These results suggest that chronic anemia may be a factor of RNFL loss.</P>
Han, Je-Chan,Lee, Jai-Yong The Korea Institute of Information and Commucation 2008 韓國通信學會論文誌 Vol.33 No.11B
The reverse acknowledgment (RA) scheme supports a fast loss recovery for negative acknowledgment (NAK)-based selective repeat automatic repeat request (SR-ARQ) by detecting a retransmission failure quickly before a retransmission timer expires. In this paper, we evaluate the performance of a NAK-based SR-ARQ protocol with the RA scheme and compare it with the conventional NAK-based SR-ARQ protocol. Particularly, we propose a simple analysis model for the transport delay of the NAK-based SR-ARQ protocol considering the traffic condition, the retransmission persistence, the timer-based retransmissions and the RA scheme's behavior. Both NAK-based SR-ARQ protocols with and without the RA scheme are implemented by using the OPNET simulator. We verified the analysis model's accuracy through the simulation results. Also, we evaluate the performance of the NAK-based SR-ARQ protocol with the RA scheme based on analysis and simulation results.
군집 별 표준곡선 매개변수를 이용한 치밀오일 생산성 예측 순환신경망 모델
한동권(Dong-kwon Han),김민수(Min-soo Kim),권순일(Sun-il Kwon) 한국정보통신학회 2021 한국정보통신학회 종합학술대회 논문집 Vol.25 No.2
치밀오일 미래 생산성 예측은 잔류오일 회수량 및 저류층 거동 분석을 위해 중요한 작업이다. 일반적으로 석유공학적 관점에서 감퇴곡선법을 이용하여 생산성 예측이 이루어지는데, 최근에는 데이터기반의 머신러닝 기법을 이용한 연구도 수행되고 있다. 본 연구에서는 딥러닝 기반 순환신경망과 LSTM, GRU 알고리즘을 이용하여 미래 생산량 예측을 위한 효과적인 모델을 제안하고자 한다. 입력변수로는 치밀오일 생산 시 산출되는 오일, 가스, 물과 이와 더불어 다양한 군집분석을 통해 산출된 표준곡선이 주요 매개변수이고, 출력변수는 월별 오일 생산량이다. 기존의 경험적 모델인 감퇴곡선법과 순환신경망 모델들을 비교하였으며, 모델의 예측성능을 향상시키기 위해 하이퍼파라미터 튜닝을 통해 최적 모델을 도출하였다. Predicting future productivity of tight oil is an important task for analyzing residual oil recovery and reservoir behavior. In general, productivity prediction is made using the decline curve analysis(DCA). In this study, we intend to propose an effective model for predicting future production using deep learning-based recurrent neural networks(RNN). LSTM, and GRU algorithms. As input variables, the main parameters are oil, gas, water, which are calculated during the production of tight oil, and the type curve calculated through various cluster analyzes. the output variable is the monthly oil production. Existing empirical models, the DCA and RNN models, were compared, and an optimal model was derived through hyperparameter tuning to improve the predictive performance of the model.
Differences in the survival rates of older patients with colorectal cancers in 2003 and 2009
Je-Wook Shin,Byung Kwan Park,Min Jung Kim,Bun Kim,Byung Chang Kim,Sung Chan Park,Kyung Su Han,Dae Kyung Sohn,Jae Hwan Oh 대한외과학회 2017 Annals of Surgical Treatment and Research(ASRT) Vol.92 No.4
Purpose: The aim of this study was to investigate survival in patients aged ≥70 years who underwent colorectal cancer surgery in 2003 and 2009. In addition, we aimed to identify the factors that could affect survival in these patients. Methods: In a cross-sectional study, a retrospective review of the data for 878 patients ho underwent colorectal cancer surgery with curative intent in the years 2003 and 2009 was performed. The primary outcome was the 5-year overall survival rate (5-OSR), and he clinicopathologic factors that could affect overall survival were analyzed. Results: The 5-OSR was 77.8% and 84.9% in 2003 and 2009, respectively (P = 0.013). Age, American Society of Anesthesiologists physical status classification, stage, type of surgery, and length of hospital stay possibly affected survival per the univariate and multivariate analyses. In patients aged ≥70 years, the 5-OSR in 2009 was 75.9%, which showed improvement compared to 53.7% in 2003 (P = 0.027). The stage, type of surgery, and hospital stay were the variables that possibly affected survival in patients aged ≥70 years per the univariate analysis, whereas the stage (III; hazard ratio [HR], 2.188; P = 0.005) and length of hospital stay (>12 days; HR, 2.307; P = 0.004), were the variables that showed statistical significance on the multivariate analysis. Conclusion: We found that early stage and shortening the length of hospital stay could affect survival in older patients with colorectal cancers. Because of limited evidence on the influence of shortening the length of hospital stay on survival in older patients, further investigations are warranted.
Han, Chan Su,Park, Kyu Sik,Choi, Hong Je,Cho, Yong Soo American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.22
<P>High-quality piezoelectric thin films have recently, been in demand for mobile sensor applications. An investigation was conducted to understand the improvements in the piezoelectric and imprint characteristics of heavily Nb-doped lead zirconate titanate thin films with an extensive range of Nb content (up to 14 mol %) beyond the typical solid ORA solubility limit of Nb. The positive effects produ-ced by the unusual doping of Nb were realized by utilizing an in situ sputtering process that did not require a subsequent annealing and poling procedure. An enhanced piezoelectric coefficient, -e(31), of -12.87 C/m(2) and a stronger shift in the coercive field, E-c,E-shift, of similar to,20 kV/cm, which are ideally useful for mobile sensor applications, were obtained for the 12 mol % Nb-doped films deposited on nonconventional buffer electrodes of Ir/TiW. The reduced oxygen vacancy concentration and preferred domain, orientation with a stronger piezoresponse induced by the Nb donor doping contributed to the enhancement of the piezoelectric properties. Potential defect dipoles aligned by a residual stress gradient along columnar structures seemed to induce an internal electric field in the Nb-doped films, leading to the preferred domain orientation, as well as the strong imprint behavior due, to a clamping of domain walls.</P>
Han, Chan Su,Choi, Hong Rak,Choi, Hong Je,Cho, Yong Soo American Chemical Society 2017 Chemistry of materials Vol.29 No.14
<P>High dielectric constant thin films processable at nearly room temperature have been demanded for various flexible electronic devices. Here, we explore the origin of abnormal dielectric behavior of amorphous CaCu3Ti4O12 (CCTO) thin films having an exceptionally high dielectric constant, in conjunction with chemical states and unusual ferroelectricity in the amorphous state. As an optimal example, the amorphous CCTO film sputtered at room temperature under an oxygen partial pressure of 3.6 mTorr exhibits a dielectric constant of similar to 192 and a dielectric loss of <0.1 at 100 Hz. The promising dielectric characteristics are unexpectedly found to originate from the evolution of ferroelectric domains, even in the amorphous state. Strong dependence of oxygen partial pressure on chemical states, vacancy formation, and ferroelectric polarization is very critical for the unexpected dielectric behavior. This may be the very first example of exploring the origin of amorphous dielectric behavior for a material that possesses space charge polarization.</P>