• Journal of the Korea Society of Computer and Information
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• v.6 no.4
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• pp.94-99
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• 2001

Recently a lot of informations is interchanged among many users through the network such as Internet. In this situation. multimedia data transfer has some problems. that are jitter, the difference of delay in arriving packets, and loss of data due to the various delay between sender and receiver. The arriving data packets are not synchronized because of those problems. Especially, an efficient method is needed to revise the sudden large changes of the delay, called spike-like delay. which is occured in explosive growth of networking. We propose efficient synchronization algorithm which controls synchronization interval and adjusts to sudden changes in networks. The algorithm, a receiver-driven adaptive synchronization method, is to synchronize the arriving data packets against spike-like delay and decrease the loss of them. In addition, another method is proposed in this paper. The method uses the probabilistic features of delay distribution appearing in general network. It is evaluated for the loss of data packets and the delay times.

• Journal of the Korea Society of Computer and Information
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• v.18 no.4
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• pp.19-26
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• 2013

Pseudo sample neural network (PSNN) is a variant of traditional neural network using pseudo samples to mitigate the local-optima-convergence problem when the size of training samples is small. PSNN can take advantage of the smoothed solution space through the use of pseudo samples. PSNN has a focus on the quantity problem in training, whereas, methods stressing the quality of training samples is presented in this paper to improve further the performance of PSNN. It is evident that typical samples and highly correlated features help in training. In this paper, therefore, kernel density estimation is used to select typical samples and correlation factor is introduced to select features, which can improve the performance of PSNN. Debris flow data set is used to demonstrate the usefulness of the proposed methods.

• The KIPS Transactions:PartD
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• v.8D no.2
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• pp.125-131
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• 2001

Various kind of disasters happens in our society. Most of them require immediate treatment to save life or to protect valuable products. When an accident happens in a place, it is reported to the headquarter of emergency measures system. According to the nature of accident several treatments orders are transmitted to the related authorities. In this paper, we introduce an intelligent emergency measures system that uses trigger mechanism of active databases. The system responds to various events spontaneously without intervention of mankind by triggering proper rules. The most important part of an action in the system is the capability of searching places to apply adequate treatments quickly. We have developed a new method for range queries and nearest neighbor queries which utilize the z-ordering technique to get fast responses. Those new methods are further extended to handle more realistic actual distance of road among positions.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.1
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• pp.62-72
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• 1996

The interface formation and reaction-product morphology between SiC and thin metal films were studied at temperatures between 550 and $1450^{\circ}C$ for various times. The typical reaction layer sequence was CoSi/CoSi+C/CoSi/CoSi+C/ $\cdots$ /SiC reaction at 1050 and $1250^{\circ}C$ for 2 h, while $Ni_2Si/Ni_2Si+C/Ni_2Si/Ni_2Si+C/ {\cdots} /SiC$ at 950 and 105$0^{\circ}C$ for 2 h. Carbon precipitated preferentially on the outer surface and crystallized as graphite above $1450^{\circ}C$ for SiC/Co reaction zone and $1250^{\circ}C$ for SiC/Ni. The mechanism of the periodic band structure formation with carbon precipitation behaviour was discussed in terms of thermodynamic considerations.

• International Area Studies Review
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• v.15 no.3
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• pp.55-76
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• 2011

In this paper, we estimate a model that incorporates key features of business cycles, co-movement among economic variables and switching between regimes of expansion and recession, to aggregate quarterly data for the NAFTA region. Two common factors reflecting the permanent and transitory components of the business cycle in the region, along with the turning points from one regime to the other, were extracted from the data by using the Kalman filter and maximum likelihood estimation approach of Kim (1994). Estimation results confirm that a typical aspect of business cycles are also observed (i.e., recessions are steeper and shorter than recoveries) in the region, and that both co-movement and that regime switching are found to be important features of the business cycle. The two common factors produce sensible representations of the trend and cycle, and the estimated turning points are in line with independently determined chronologies. It also turns out that the degree of synchronization between the NAFTA region and Korea, has significantly increased since the entry into force of the NAFTA.

• Cross-Cultural Studies
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• v.40
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• pp.61-90
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• 2015

The imagery of Ophelia appeared in Russian literature in the middle of the $19^{th}$ century. In contrast with Hamlet, whose name had been always in the center of the most intense debates through centuries, Ophelia had been understood relatively monotonously and simply associated with the images of a chaste maiden, a tragic heroine and a devoted lover. Only after the feminist literary criticism shed new light on the complicated inner world of the young girl, the imagery of Ophelia radically changed, and now it is not difficult to encounter various Ophelias on the contemporary stages and culture. In this paper we study the remarkable changes of the imagery of Ophelia in Russian modernism poetry, analysing A. Blok, A, Akhmatova, M. Tsvetaeva's Ophelia poems. Ophelia in Russian modernism, on the one hand, succeeding to the traditional view on Ophelia in $19^{th}$ century, assumes interesting new aspects, sometimes preempting feminist point of view.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.103-110
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• 2022

This paper attempted to systematize the settlement problem of Moroccan immigrants and the plan for Moroccan cooperation for various purposes by understanding Morocco's religious background and historical and cultural characteristics. Morocco is open to trade and typical in the social and cultural distance. It has been exchanging Western European culture, including Spain and France, but maintains a typical Muslim. In particular, Morocco was once a center of triangular trade, a diaspora and logistics hub, and advanced to North America. It will continue to serve as a bridgehead for the cultural spread of global square-traded. Now, Moroccan trade is formed around France and other European regions. This is encountered in Korea and other countries around the world due to the progress of opening and industrialization in the African region. Since COVID-19, soft power has been increasing women's accessibility. As a global triangular strategic location for business or service financing and regional access to Morocco, we demonstrate the local acceptance of cultural industries and services, the soft power of Korea.

• Journal of the Korea Organic Resources Recycling Association
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• v.3 no.2
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• pp.79-89
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• 1995

Changes of microbial activity and physicochemical environment during composting of papermill sludge(PMS) in the pilot plant equipped with an agitated bed reactor were monitored for establishing the efficient composting system. Microbial activity determined as the evolution of $CO_2$ increased for the first 10 days after introduction of PMS to the reactor and decreased thereafter. Population changes of microorganisms in the reactor-PMS were not typical as in windrow system. The ratio of thermophilic bacteria to mesophilic bacteria, however, increased slowly even 23 days after introduction. Temperature of PMS increased rapidly from the first day and reached $62^{\circ}C$ at 7 days after introduction and decreased slowly thereafter. The acidity of PMS was pH 6.8 initially, increased to pH 8.0 after 7 days and decreased to pH 7.4 after 23 days. Redox potential(Eh) of PMS was -320mV at the beginning of composting, but it was increased with time to reach -15mV after 23 days composting. However, Eh of PMS pre-sterilized before measurement was average 50mV, regardless of composting periods indicating the major role of microorganisms during composting process. Water content of PMS was 67% initially and decreased to about 50% after 23 days composting in the reactor. Less than 13 days-old compost inhibited growth of radish in the container mixture with bed soil. Based on statistical analysis of microbial and physicochemical parameters of PMS during composting, an equation was developed for determining compost maturity. A number of experiments using various organic wastes are required before application of the formular to the practical use.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.2
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• pp.82-88
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• 2005

A compensation scheme for a class of linearly parameterized systems is presented. The compensator consists of a typical linearizing control and an adaptive observer with integration type update law, which is based on Speed Gradient (SG) algorithm.. Instead of the intermediate functions of the compensation schemes suggested by other researchers, the proposed compensator is designed with some design functions which guarantee the growth, convexity, attainability, and pseudo gradient conditions in the update law. The scheme achieves the asymptotic stability of the tracking error and the boundedness of the estimation errors. A numerical example is given to demonstrate the validity of the proposed design.

• 한국해양학회지
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• v.11 no.1
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• pp.34-38
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• 1976

Monthly observation of phytoplankton were made from September, 1974 to June 1975 at three stations in the Masan Bay. Sixty three species of phytoplankton (diatoms), representing 25 genera were taken in this study. Of these Skeletonema costatum, Eucampis zoodiacus, Ditylum brightwellii, Chaetoceros debilis, Coscinosira polychorda, and Leptocylindrus danicus were the dominant species in this area. By the ecological division the neritic species occupied 85.71% of total diatom diversity and it showed the characteristics of emayment. Diversity index(H) were the lowest in January and May in surface, while the highest in October. Phytoplankton standing crop varied extensively by months; ranging from 3,780 to 7,642,798 cells/l. total phytoplankton standing crop showed three major peaks in September, December and May. After bloom diatom standing crop were decreased gradually and showed minimum in November and February.