• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2003.11a
• /
• pp.111-116
• /
• 2003

Recently, power-electronics equipments or machine that microprocessor is included and computers have been installed continuously in industrial process or region of electronics customer. So concern for power quality, especially sags has been increased. Because those equipments are very sensitive to sags. The sag is phenomenon that magnitude of load voltage temporarily decreases because of power system fault. If a certain equipment in industrial process have any trouble result from sag, it can cause utility to be charged for enormous economics loss. Therefore it need to analyze the characteristic of sag and then mitigation method for sags in distribution system in oder to increase reliability. This paper gives an overview of sags characteristic due to short circuit fault in distribution system and after a general discussion of the various forms mitigation, gives a sags mitigation method with concentrating on mitigation-device interface method, especially FCL that is Fault Current Limiter.

• Proceedings of the KIEE Conference
• /
• 1995.07a
• /
• pp.394-396
• /
• 1995

This paper present fuzzy control technique for the control of output voltage and improvement of UPS wave forms. General UPS has the harmonics in carrier because of output of PWM signal using analog circuit. Output voltage is controlled by selecting PWM data to improve these problems, PWM signal discreted is written on ROM and analog circuit is removed at the system and output voltage is controlled by selecting PWM data by fuzzy controller.

• Communications for Statistical Applications and Methods
• /
• v.17 no.2
• /
• pp.255-261
• /
• 2010

A class of threshold-asymmetric GRACH(TGARCH, hereafter) models has been useful for explaining asymmetric volatilities in the field of financial time series. The cumulative impulse response function of a conditionally heteroscedastic time series often measures a degree of unstability in volatilities. In this article, a general form of the cumulative impulse response function of the TGARCH model is discussed. In particular, We present formula in their closed forms for the first two lower order models, viz., TGARCH(1, 1) and TGARCH(2, 2).

• Journal of the Korean Society of Food Culture
• /
• v.11 no.1
• /
• pp.131-141
• /
• 1996

Food consumption patterns are predictors of nutritional status at all age levels and vary among and between different age groups. This study was designed to asses food habits and fast food eating patterns of college students in Ulsan area through questionnaries. Data from 330 useable forms was analyzed for percent differences, frequency of consumption, and statistical significance of differences between male and female students (T-test and chi square methods were utilized). Food habit score of female students was significantly higher than of male students. The reason for using fast food chain was 'convenience' or 'good taste'. The most preferred food by subjects was noodle or dumpling and least preferred food was pizza. In general, they had a higher satisfaction scores in taste and service of fast food and lower scores in amount and price of it. From this results it appears there is a need for developing domestic brand fast food to lower the price of fast food and giving the nutrition education for proper food selections and eating patterns.

• Communications of the Korean Mathematical Society
• /
• v.23 no.1
• /
• pp.81-93
• /
• 2008

In [3, 9], using the theory of noncommutative Dirichlet forms in the sense of Cipriani [6] and the symmetric embedding map, authors constructed the KMS-symmetric Markovian semigroup $\{S_t\}_{t{\geq}0}$ on a von Neumann algebra $\cal{M}$ with an admissible function f and an operator $x\;{\in}\;{\cal{M}}$. We give a sufficient and necessary condition for x so that the semigroup $\{S_t\}_{t{\geq}0}$ acts separately on diagonal and off-diagonal operators with respect to a basis and study some results.

• Bulletin of the Korean Chemical Society
• /
• v.3 no.3
• /
• pp.122-129
• /
• 1982

In order to extend our understanding on the multiple inhibition enzyme kinetics, a general equation of an enzyme reaction in the presence of two different reversible inhibitors was derived by what we call "match-box mechanism" under the combined assumption of steady-state and quasi-equilibrium for inhibitor binding. Graphical methods were proposed to analyze the multiple inhibition of an enzyme by any given sets of different inhibitors, i.e., competitive, noncompetitive, and uncompetitive inhibitors. This method not only gives an interaction factor $({\alpha})$ between two inhibitors, but also discerns ${\alpha}_1$ and ${\alpha}_2$ with and without substrate binding, respectively. The factors involved in the dissociation constants of inhibitors can also be evaluated by the present plot. It is also shown that the present kinetic approach can be extended to other forms of activators or hydrogen ions with some modification.

• Bulletin of the Korean Chemical Society
• /
• v.10 no.6
• /
• pp.529-535
• /
• 1989

A general perturbation series solution of the Smoluchowski equation is applied to investigate the rate of recombination and the remaining probability of a pair of particles in liquids. The radiative boundary condition is employed and the convergence of the perturbation series is analyzed in terms of a convergene factor in time domain. The upper bound to the error introduced by the n-th order perturbation scheme is also evaluated. The long time behaviors of the rate of recombination and the remaining probability are found to be expressed in closed forms if the perturbation series is convergent. A new and efficient method of purely numerical integration of the Smoluchowski equation is proposed and its results are compared with those obtained by the perturbation method. For the two cases where the interaction between the particles is given by (i) the Coulomb potential and (ii) the shielded Coulomb potential, the agreement between the two results is found to be excellent.

• Bulletin of the Korean Chemical Society
• /
• v.12 no.5
• /
• pp.583-588
• /
• 1991

A series of dimesogenic compounds having two identical, terminal Schiff base type mesogens and a central polymethylene spacer were prepared and their properties were compared with those of the corresponding monomesogenic compounds. The mesomorphic properties of the compounds were studied by differential scanning calorimetry and on a hot-stage of a polarizing microscope. All of the dimesogenic compounds formed mesophases enantiotropically with the exception of pentamethylene-1,5-bis(4-oxybenzylidene 4-n-butylaniline). This compound was monotropic and formed only a nematic phase on heating the solid, whereas it formed nematic as well as smectic A phases on cooling the isotropic liquid. Those compounds containing longer (octamethylene and decamethylene) spacers favored the formation of nematic phase whereas those having shorter (dimethylene and tetramethylene) spacers formed smectic phases. In general, the variety of mesophase forms exhibited by the dimesogenic compounds was significantly less than that shown by the corresponding monomesogenic compounds.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.16 no.5
• /
• pp.215-223
• /
• 2021

3D data can be categorized into two parts : Euclidean data and non-Euclidean data. In general, 3D data exists in the form of non-Euclidean data. Due to irregularities in non-Euclidean data such as mesh and point cloud, early 3D deep learning studies transformed these data into regular forms of Euclidean data to utilize them. This approach, however, cannot use memory efficiently and causes loses of essential information on objects. Thus, various approaches that can directly apply deep learning architecture to non-Euclidean 3D data have emerged. In this survey, we introduce various deep learning methods for mesh and point cloud data. After analyzing the operating principles of these methods designed for irregular data, we compare the performance of existing methods for shape classification and segmentation tasks.

• Journal of English Language & Literature
• /
• v.60 no.2
• /
• pp.269-293
• /
• 2014

Written as her last collaboration with the Provincetown Players, Susan Glaspell's The Verge is an exceptional play in that its formal experiment and modernist theme are clear of her general modernist ambivalence which combines a uniquely American and feminist expression of the modernist spirit with rather conventional forms. Following critics' brief and generalizing comments on the play's protagonist embodying modernist formalism and alienation, this paper offers a full and concrete survey detailing the tenets and the slogans of Modernism inlaid in the play. Its main argument is that Glaspell strategically deployed the metaphysics of egoism, anarchic hostility to the collectiveness of bourgeois society, and formalist preoccupation in Modernism in representing a female egoist's longing for a new order of society, illustrating an intersection between Modernism and feminism. It concludes that The Verge is an extremely rare case of modernist literature where a play, allegedly the least modernist genre of all according to Christopher Innes, exemplifies the "eloquent critical acts entangled in the creative work" which Michael Levenson lists as a distinct feature of modernist texts.