• Bulletin of the Korean Mathematical Society
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• v.49 no.1
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• pp.155-163
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• 2012

Let E be an elliptic curve over $\mathbb{Q}$. Using Iwasawa theory, we give what seems to be the first general upper bound for the order of vanishing of the p-adic L-function at s = 0, and the $\mathbb{Z}_p$-corank of the Tate-Shafarevich group for all sufficiently large good ordinary primes p.

• Journal of Cardiovascular Imaging
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• v.31 no.4
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• pp.200-206
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• 2023

BACKGROUND: Right ventricular (RV) dysfunction is a significant risk of major adverse cardiac events in patients with acute heart failure (AHF). In this study, we evaluated RV-pulmonary artery (PA) coupling, assessed by tricuspid annular plane systolic excursion (TAPSE)/pulmonary artery systolic pressure (PASP) and assessed its prognostic significance, in AHF patients. METHODS: We measured the TAPSE/PASP ratio and analyzed its correlations with other echocardiographic parameters. Additionally, we assessed its prognostic role in AHF patients. RESULTS: A total of 1147 patients were included in the analysis (575 men, aged 70.81 ± 13.56 years). TAPSE/PASP ratio exhibited significant correlations with left ventricular (LV) ejection fraction(r = 0.243, p < 0.001), left atrial (LA) diameter(r = -0.320, p < 0.001), left atrial global longitudinal strain (LAGLS, r = 0.496, p < 0.001), mitral E/E' ratio(r = -0.337, p < 0.001), and right ventricular fractional area change (RVFAC, r = 0.496, p < 0.001). During the median follow-up duration of 29.0 months, a total of 387 patients (33.7%) died. In the univariate analysis, PASP, TAPSE, and TAPSE/PASP ratio were significant predictors of mortality. After the multivariate analysis, TAPSE/PASP ratio remained a statistically significant parameter for all-cause mortality (hazard ratio [HR], 0.453; p = 0.037) after adjusting for other parameters. In the receiver operating curve analysis, the optimal cut-off level of TAPSE/PASP ratio for predicting mortality was 0.33 (area under the curve = 0.576, p < 0.001), with a sensitivity of 65% and a specificity of 47%. TAPSE/PASP ratio < 0.33 was associated with an increased risk of mortality after adjusting for other variables (HR, 1.306; p = 0.025). CONCLUSIONS: In AHF patients, TAPSE/PASP ratio demonstrated significant associations with RVFAC, LA diameter and LAGLS. Moreover, a decreased TAPSE/PASP ratio < 0.33 was identified as a poor prognostic factor for mortality.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.357-367
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• 2010

In this study, several design and construction cases of the pile bent system for bridges were introduced. The lateral displacement of the pile bent system is larger than the displacement of pile cap system, due to the smaller bending stiffness and the longer unsupported length. So, the analysis of the lateral pile displacement is main factor for the design of pile bent system and superstructure. For the accurate estimation of the pile displacement, an iterative analysis method was developed. The superstructure was analyzed regarding the pile foundation as $6{\times}6$ spring and the substructure was analysed using non-linear load transfer curves (p-y, t-z, q-z curve). And, to verify this analysis method, the estimated displacements are compared with the results of lateral load test. This analysis method is expected to be a viable alternative approach for the design of bridge foundation hereafter.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1479-1484
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• 2010

Photosynthesis uses light energy to drive the oxidation of water at an oxygen-evolving catalytic site within photosystem II (PSII). Chlorophyll binding by the photosystem II subunit S protein, PsbS, was found to be necessary for energy-dependent quenching (qE), the major energy-dependent component of non-photochemical quenching (NPQ) in Arabidopsis thaliana. It is proposed that PsbS acts as a trigger of the conformational change that leads to the establishment of nonphotochemical quenching. However, the exact structure and function of PsbS in PSII are still unknown. Here, we clone and express the recombinant PsbS gene from Arabidopsis thaliana in E. coli and purify the resulting homogeneous protein. We used various biochemical and biophysical techniques to elucidate PsbS structure and function, including circular dichroism (CD), fluorescence, and DSC. The protein shows optimal stability at $4^{\circ}C$ and pH 7.5. The CD spectra of PsbS show that the conformational changes of the protein were strongly dependent on pH conditions. The CD curve for PsbS at pH 10.5 curve had the deepest negative peak and the peak of PsbS at pH 4.5 was the least negative. The fluorescence emission spectrum of the purified PsbS protein was also measured, and the ${\lambda}_{max}$ was found to be at 328 nm. PsbS revealed some structural changes under varying temperature and oxygen gas condition.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.134-136
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• 1993

This paper presents a novel and efficient method to calculate the critical point of voltage collapse. Conjugate gradient and modified Newton-Raphson methods are employed to calculate two pairs of multiple load flow solutions for two operating conditions, i.e., both +mode and -mode voltages for two loading conditions respectively. Then these four voltage magnitude-load data sets of the bus which is most susceptible to voltage collapse, are fitted to third order polynomial using Lagrangian interpolation in order to represent approximate nose curve (P-V curve). This nose curve locates first estimate of the critical point of voltage collapse. The procedure described above is repeated near the critical point and the new estimate will be very close to the critical point. The proposed method is tested for the eleven bus Klos-Kerner system, with good accuracy and fast computation time.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.590-596
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• 1999

The effect of evaporative cooling in alleviating seasonal variations of dairy cows raised in AlMarai Dairy Farms in the Kingdom of Saudi Arabia were studied using milking record collected during the period of 1991 to 1996. The data included 13303 and 8137 records represented winter and summer calving seasons. Evaporative cooling system improved production for cows calved in summer. The least square means of milk yield were 9631 and 9556 liter for cows calved in winter and summer seasons but no significant differences (p<0.05) were observed between the yield of two seasons. No significant effect of season on calving under evaporative cooling on most of the biweekly points of the lactation curve. The farm, parity and milk level showed a significant effect on the shape of the curve. Functions of the lactation curve like initial yield, 305 MY, peak yield, time of peak and duration were estimated for each phase of the lactation curve.

• Wind and Structures
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• v.22 no.1
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• pp.65-87
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• 2016

The wind velocity profile over the height of a structure in high intensity wind (HIW) events, such as downbursts, differs from that associated with atmospheric boundary layer (ABL) winds. Current design codes for lattice transmission structures contain only limited advice on the treatment of HIW effects, and structural design is carried out using wind load profiles and response factors derived for ABL winds. The present study assesses the load-deformation curve (capacity curve) of a transmission tower under modeled downburst wind loading, and compares it with that obtained for an ABL wind loading profile. The analysis considers nonlinear inelastic response under simulated downburst wind fields. The capacity curve is represented using the relationship between the base shear and the maximum tip displacement. The results indicate that the capacity curve remains relatively consistent between different downburst scenarios and an ABL loading profile. The use of the capacity curve avoids the difficulty associated with defining a reference wind speed and corresponding wind profile that are adequate and applicable for downburst and ABL winds, thereby allowing a direct comparison of response under synoptic and downburst events. Uncertainty propagation analysis is carried out to evaluate the tower capacity by considering the uncertainty in material properties and geometric variables. The results indicated the coefficient of variation of the tower capacity is small compared to those associated with extreme wind speeds.

• YAKHAK HOEJI
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• v.37 no.5
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• pp.427-436
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• 1993

The pharmacokinetics and relationship between in vitro dissolution and in vivo fraction absorbed were investigated after intravenous(iv) injection of omeprazole(OMZ), oral administration of OMZ capsules and rectal administration of 8 types of suppositories. The plasma concentration of OMZ (C$_{p}$)-time (t) curve after iv. administration fitted a two-compartment open model and the equation which best fitted the pharmacokinetics of OMZ was $C_{p}$ = 13.936 $e^{-8.78t}$+2.973 $e^{-0.716t}$. The bioavailabilities of OMZ in Witepsol H15 base (Supp-2) and PEG 4000 base (Supp-6) suppositories were 40.7% and 33.4%, respectively, which are higher(p<0.001) than 13% of oral administration of capsule. The avoidance fractions of the first-pass metabolism for Supp-2 and Supp-6 suppositiories were 31.8% and 23.4%, respectively, suggesting that the rectal application of OMZ may be a more adequate route of administration than oral one.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.3
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• pp.553-563
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• 1994

The behavior of earth retaining structure was investigated by considering coupling between soil springs in elasto-plastic soil. For the computation of soil reaction, soil on both sides of walls was simplified as e1asto-plastic springs, and the required horizontal displacement to mobilize Terzaghi's active and passive state was applied to construct the p-y curve. Reliability on computer program developed is verified through the comparison between prediction and in-situ measurements. Based on the results obtained, it is found that the prediction by using coupling between soil springs simulates well the general trend observed by the in-situ measurements. It is also found that the horizontal displacement required for the active state gives a very small effect to the displacement of walls in the sandy soil.

• Journal of KIISE:Computer Systems and Theory
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• v.35 no.7
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• pp.327-331
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• 2008

Optimal Extension Fields (OEFs) are finite fields of a special form which are very useful for software implementation of elliptic curve cryptosystems. Bailey and Paar introduced efficient OEF arithmetic algorithms including the $p^ith$ powering operation, and an efficient algorithm to construct OEFs for cryptographic use. In this paper, we give a counterexample where their $p^ith$ powering algorithm does not work, and show that their OEF construction algorithm is faulty, i.e., it may produce some non-OEFs as output. We present improved algorithms which correct these problems, and give improved statistics for the number of OEFs.