• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.233-241
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• 1997

New UBV Photometric observations for a close binary RZ Cas were obtained at the Chungbuk National University Observatory for 42 nights from October 1991 to March 1993, and standardized UBV light curves were constructed. From the primary light curves, the eight minimum times were determined by using a new light element. We confirmed the primary minimum was totality and derived the average duration was 18.1 minutes corresponding to $0.^{p}01$. The photometric and spectroscopic solutions were calculated with the obtained light curves and the radial velocity curves of Duerbeck & Hanel(1979) by using Wilson-Devinney method. From these values, the absolute dimensions of this binary system were estimated.

• Economic and Environmental Geology
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• v.5 no.2
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• pp.77-86
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• 1972

The system NaAlSiO_4-KAlSiO_4-SiO_2-H_2O, Bowen's "Petrogeny's Residua System" of course is extremely important in understanding the phase relationships of igneous and metamorphic rock in the continental crust. The phase relationships in this system, however, have not been completely established in the P-T range above the Mohorovicic discontinuity. They need to be established. In this study, the most probable sequence of P-T curves around a quaternary invariant point(~5Kb/${\sim}635^{\circ}C$) in the system using Schreinemakers' rule, is deduced, essentially on the basis of Morse's(1969a and b) experimental data. Possible modifications of the sequence of the P-T curves considering likely changes of the invariant chemogram are also considered. It is concluded that the sequence of P-T curves around the invariant point (~5Kb/${\sim}635^{\circ}C$) is (L), (Anl), (Or), (V), (Ne) and (Ab) on the P-T projection, where the P-T curve (L) is extended towards lower P-T regions, and the (Anl) curve is extended towards a region of higher temperature and lower pressure from the invariant point respectively.

• Korean Journal of Acupuncture
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• v.27 no.1
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• pp.13-22
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• 2010

Objectives: The information on the depth where pulse wave appears is as important as pulse waveform. The aim of this study was to classify pulse pattern using pressure-height(P-H) volume-curve by 5 applied pressure levels to find out the information on the depth of pulse and interpret the floating & sinking pulse in oriental medical pulse diagnosis. Methods: We used 3 dimensional pulse imaging analyser (DMP-3000, DAEYOMEDI Co., Korea), which measures radial pulse waveforms noninvasively by way of tonometric method at 5 applied pressure levels, and shows P-H volume-curves by applied pressure. 448 subjects were enrolled, pulse waveforms were measured and the P-H volume-curves were gained on the three locations of Chon, Kwan, and Cheok. Results: Gained P-H volume curves were classified into 3 types ; increase type, decrease type, and increase-decrease type. Increase-decrease type appeared more often on Chon and Kwan, while increase type appeared more often on Cheok. In a few cases, decrease-type appeared on Chon and Kawn, however it never appeared on Cheok. Conclusions: Through the classification of pulse by P-H volume-curve, we gained the information on the depth of pulse. We speculate the decrease type as floating pulse, the increase-decrease type as middle pulse, and the increase type as sinking pulse in oriental medical pulse diagnosis. After more researches on P-H volume-curve by applied pressure, the P-H volume-curve may be used as an important factor for pulse diagnosis.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.4
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• pp.1051-1061
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• 1995

In order perform leak-before-break design of nuclear piping systems and integrity evaluation of reactor vessels, full stress-strain (.sigma. - .epsilon.) curves and fracture resistance (J-R) curves are required. However it is time-consuming and expensive to obtain J-R curves experimentally. The objective of this paper is to develop two methods for J-R curve prediction. In the first method, elastic-plastic finite element analyses for a series of crack length / specimen width ratio were performed. Accordingly the load versus load line displacement (P .delta.) curve corresponding to the fracture strain is obtained and the J-R curve based on the generalized locus method is obtained. In the second method, the correlation between .sigma.-.epsilon. curves and J-R curves was statistically analyzed and an empirical equation to predict the J-R curve from the .sigma.-.epsilon. test result is proposed. A good correlation between the predicted results based on the proposed methods and the experimental ones is obtained.

• Steel and Composite Structures
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• v.25 no.5
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• pp.557-569
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• 2017

Moment-thrust-curvatures ($M-P-{\Phi}$ curves) are fundamental quantities for detailed descriptions of basic properties such as stiffness and strength of a section under axial loads required for accurate computation of the deformations of reinforced concrete or composite columns. Currently, the finite-element-based methods adopting small fibers for analyzing a section are commonly used for generating the $M-P-{\Phi}$ curves and they require large amounts of computational time and effort. Further, the conventional numerical procedure using the force-control method might encounter divergence problems under high compression or tension. Therefore, this paper proposes a divergence-free approach, combining the use of the displacement-control and the Quasi-Newton scheme in the incremental-iterative procedure, for generating the $M-P-{\Phi}$ curves of arbitrary sections. An efficient method for computing the strength from concrete components is employed, where the stress integration is executed by layer-based algorithms. For easy modeling of residual stress, cross sections of structural steel components are meshed into fibers for strength resultants. The numerical procedure is elaborated in detail with flowcharts. Finally, extensive validating examples from previously published research are given for verifying the accuracy of the proposed method.

• Tuberculosis and Respiratory Diseases
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• v.42 no.2
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• pp.218-225
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• 1995

Background: Airway resistance(Raw) is measured with the body plethysmograph by displaying the relationship between airflow and alveolar pressure($V/P_A$). If the resistance curve on $V/P_A$ tracing is curved or looped, the estimation of Raw is difficult. This study was designed to examine wheather there is any correlation between the shape of resistance curve and the clinical status and the pulmonary function of patients. Methods: The 146 pulmonary disease patients with increased Raw were included in this study. The shapes of resistance curves on $V/P_A$ tracing with body plethysmograph during quiet breathing were analyzed and compared with pulmonary function. Results: The results were as follows ; 1) The shapes of resistance curves were summarized in 5 categories; type 1: linear, type 2: ovoid, type 3: sigmoid, type 4: scoop, type 5: paisley. The type 3 except 1 case, type 4 and type 5 were found to have loop mainly in expiratory phase. 2) Although the shapes of resistance curves were not typical for specific disease, the resistance curves of acute disease tended to belong to type 1 or 2 and those of chronic airflow obstruction tended to belong to type 3, 4 or 5. But resistance curves of bronchial asthma and destructive lung with tuberculosis showed all types in proportion to degree of airflow obstruction or destruction of parenchyme. 3) In the cases of resistance curves going to type 5 rather than type 1 and those with looping, airflow obstuction tended to be severe and airway resistance and residual volume tended to increase. Conclusions: Analysis of resistance curve on $V/P_A$ tracing measuring airway resistance is helpful for judging degree of airflow obstruction and air trapping. Although the shape of resistance curve is not typical for specific disease, there is a close association between looping and airway obstruction.

• Journal of KIISE:Software and Applications
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• v.27 no.1
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• pp.50-61
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• 2000

Recently the stereo vision based on conics has received much attention by many authors. Conics have many features such as their matrix expression, efficient correspondence checking, abundance of conical shapes in real world. Extensions to higher algebraic curves met with limited success. Although irreducible algebraic curves are rather rare in the real world, lines and conics are abundant whose products provide good examples of higher algebraic curves. We consider plane algebraic curves of an arbitrary degree $n{\geq}2$ with a fully calibrated stereo system. We present closed form solutions to both correspondence and reconstruction problems. Let $f_1,\;f_2,\;{\pi}$ be image curves and plane and $VC_P(g)$ the cone with generator (plane) curve g and vertex P. Then the relation $VC_{O1}(f_1)\;=\;VC_{O1}(VC_{O2}(f_2)\;∩\;{\pi})$ gives polynomial equations in the coefficient $d_1,\;d_2,\;d_3$ of the plane ${\pi}$. After some manipulations, we get an extremely simple polynomial equation in a single variable whose unique real positive root plays the key role. It is then followed by evaluating $O(n^2)$ polynomials of a single variable at the root. It is in contrast to the past works which usually involve a simultaneous system of multivariate polynomial equations. We checked our algorithm using synthetic as well as real world images.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.219-219
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• 2013

The effect of an electron blocking layer (EBL) on V-I curves in GaN/InGaN multiple quantum well is investigated. For the first time, we found that curves were intersected at 3.012 V and analyzed the reason for intersection. The forward voltage in LEDs with an p-AlGaN EBL is larger than without p-AlGaN EBL at low injection current because the Mg doping efficiency for p-GaN layer was higher than that of p-AlGaN layer. However, the forward voltage in LEDs with an p-AlGaN EBL is smaller than without p-AlGaN EBL at high injection current because the carriers overflow from the active layer when injection current increases in LEDs without p-AlGaN EBL and in case of LED with p-AlGaN EBL, the carriers are blocked by EBL.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.575-582
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• 2002

To find a lateral long term behavior of driven H-piles in embankment, inclinometer is installed at pile and measurement is done during a year. When behavior of measured slope angles is in accord with behavior of nonlinear p-y curves(Reese, Murchison and O'Neil, Matlock's p-y analysis), maximum displacement of pile head, maximum stresses and maximum bending of pile obtained from the numerical analysis are shown. As results, maximum lateral displacement at pile head, maximum stress and maximum bending moment of pile are shown linear behavior. And maximum lateral load, maximum lateral displacement, and maximum bending moment at pile head obtained from the numerical analysis are 8∼12.4tonf, 9∼10.1mm, and 10.39∼12.67tonf-m per pile according to the curves, respectively.

• Journal of applied mathematics & informatics
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• v.30 no.1_2
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• pp.101-109
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• 2012

In this paper, we present an algorithm for computing the number of points on the Jacobian varieties of one-dimensional family of genus 3 nonhyperelliptic curves over finite fields. We also provide the explicit formula of the characteristic polynomial of the Frobenius endomorphism of the Jacobian of $C:y^3=x^4+{\alpha}$ over a finite field $\mathbb{F}_p$ with $p{\equiv}1$ (mod 3) and $p{\neq}1$ (mod 4). Moreover, we give some implementation results using Gaudry-Schost method. A 162-bit order is computed in 97 s on a Pentium IV 2.13 GHz computer using our algorithm.