• Title/Summary/Keyword: $C^*$ 예측

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Predictive Factors of Major Adverse Cardiac Events after Drug-Eluting Balloon Angioplasty for In-Stent Restenosis Lesion (스텐트 내 재협착 병변에서 약물용출 풍선확장술 후 주요 심장사건 발생의 예측인자)

  • Lee, Doo Hwan;Kim, In Soo;Kong, Chang gi;Han, Jae Bok
    • Journal of the Korean Society of Radiology
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    • v.14 no.2
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    • pp.179-191
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    • 2020
  • The aim of this study was to investigate the predictors of major adverse cardiac events (MACE) in patients with drug-eluting balloon (DEB) for in-stent restenosis (ISR) lesion. Total of 257 patients who developed ISR on follow-up coronary angiography (66.1 ± 10.1years, 172 males) in Chonnam National University Hospital between October 2012 and January 2017 were enrolled. We divided the patients into two groups; group I (MACE group; n= 35) and group II (No MACE group; n= 222). A multivariate logistic regression analysis revealed that type IV ISR (HR=4.179, 95% C.I.=1.851-9.437 p= 0.001), lesion length > 25 mm (HR=8.773, 95% C.I.=1.898-40.546 p=0.005), number of ISR recurrence > 2 (HR=4.693, 95% C.I.=1.259-17.490 p= 0.021) were independent factors for MACE after DEB in ISR lesions.

ALGORITHMS FOR AGGREGATE INTERLOCK CONSTITUTIVE BEHAVIOR AT R/C CRACKS (철근콘크리트 균열에서의 골재맞물림 거동에 대한 해석연구)

  • 최기봉;황철성
    • Magazine of the Korea Concrete Institute
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    • v.1 no.2
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    • pp.113-120
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    • 1989
  • 이 논문에서는 철근콘크리트 균열에서의 활동전단변형에대해 골재맞물림에 따라 수반되는 저항응력을 예측할 수 있는 해석방법들이 개발되어졌다. 이러한 방법들은 거의 정확하게 실험결과들을 예측하였으며 초기 균열폭, 콘크리트 압축강도, 최대 골재크기, 그리고 균열틈에 따라 수반되는 구속력에 의해 영향을 받는 골재맞물림 거동에 대한 해석연구를 위해 사용되어졌다.

$C_a/C_c$ for Marine Clay at Southern Part of Korea by Laboratory Consolidation Tests (실내압밀시험에 의한 남해안 해성점토의 $C_a/C_c$)

  • 김규선;임형덕;이우진
    • Journal of the Korean Geotechnical Society
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    • v.15 no.6
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    • pp.87-98
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    • 1999
  • Consolidation settlements on soft clay are often greatly and potentially damaging to structures. Currently, large-scale projects are in planning or progressing in Korea. These structures will be constructed on both thick and soft clay layers, and so the accurate evaluation of magnitude of settlement is required at every step in design and construction. Especially, secondary compression may play an important role in consolidation settlements of soft clay. Generally, the magnitudes of secondary compression are evaluated by laboratory and in-situ consolidation tests. The empirical $C_a/C_c$ may be economical, fast and powerful tool in estimating secondary consolidation settlement. However, the databases of the $C_a/C_c$ at construction site in Korea are insufficient. The purpose of this study is to investigate the relationship of $C_a/C_c$ on marine clay near the southern sea in Korea. A series of incremental loading consolidation tests (measuring base pore water pressure) is peformed. It was found that the $C_a/C_c$ on undisturbed marine clay is 0.0397.

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Modeling of the Charge-discharge Behavior of a 12-V Automotive Lead-acid Battery (차량용 12-V 납축전지의 충·방전 모델링)

  • Kim, Ui Seong;Jeon, Sehoon;Jeon, Wonjin;Shin, Chee Burm;Chung, Seung Myun;Kim, Sung Tae
    • Korean Chemical Engineering Research
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    • v.45 no.3
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    • pp.242-248
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    • 2007
  • For an optimal design of automotive electric system, it is important to have a reliable modeling tool to predict the charge-discharge behaviors of the automotive battery. In this work, a two-dimensional modeling was carried out to predict the charge-discharge behaviors of a 12-V automotive lead-acid battery. The model accounted for electrochemical kinetics and ionic mass transfer in a battery cell. In order to validate the modeling, modeling results were compared with the experimental data of the charge-discharge behaviors of a lead-acid battery. The discharge behaviors were measured with three different discharge rates of C/5, C/10, and C/20 at operating temperature of $25^{\circ}C$. The batteries were charged with constant current of 30A until the charging voltage reached to a predetermined value of 14.24 V and then the charging voltage was kept constant. The discharge and charge curves from the measurements and modeling were in good agreement. Based on the modeling, the distributions of the electrical potentials of the solid and solution phases, the porosity of the electrodes, and the current density within the electrodes as well as the acid concentration can be predicted as a function of charge and discharge time.

Studies on the Prediction of the Shelf-life of Kochujang through the Physicochemical and Sensory Analyses during Storage (고추장 저장 중 이화학 및 관능적 특성에 의한 유통기간 예측에 대한 연구)

  • Lee, Ki-Young;Kim, Hyung-Suk;Lee, Hyeon-Gyu;Han, Ouk;Chang, Un-Jae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.4
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    • pp.588-594
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    • 1997
  • In this study, the shelf-life of Kochujang during storage was predicted through physicochemical and sensory analyses. Amino nitrogen, lightness, characteristics of surface color, pH and number of viable cell counts in Kochujang decreased during storage, while ammonia nitrogen, titratable acidity and viscosity increased. Among the physicochemical analyses, amino nitrogen content exhibited the highest correlation with sensory score. The marginal amounts of amino nitrogen was 170.6mg%. Degradation rate of amino nitrogen was a first order reaction. Q$_{10}$-value and the activation energy of Kochujang during storage were 1.80 and 8.6kca1/mol, respectively. The shelf-life Predicted of Kochujang at each storage temperature was calculated. The shelf-life predicted was 467 days at 1$0^{\circ}C$, 261 days at 2$0^{\circ}C$ and 133 days at 35$^{\circ}C$.

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Dynamic Correction of DES Model Constant for the Advanced Prediction of Supersonic Base Flow (초음속 기저유동의 우수한 예측을 위한 DES 모델상수의 동적 보정)

  • Shin, Jae-Ryul;Choi, Jeong-Yeol
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.38 no.2
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    • pp.99-110
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    • 2010
  • The DES analysis of strong compressibility flow, LES mode is intentionally performed in boundary layer with the conventional empirical constant $C_{DES}$ value of 0.65. In this study, an expression is suggested to determine the $C_{DES}$ value dynamically by using a distribution function of the ratio of turbulence length scale and wall distance which is used in S-A DDES model for RANS mode protection. The application of the dynamic $C_{DES}$ presents better prediction than previous results those used constant but different $C_{DES}$ values.