• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.2
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• pp.173-177
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• 2001

We introduce cascade products, wreath products, sums and joins of TL-finite state machines and investigate their algebraic structures. Also we study the relations with other products of TL-finite state machines.

• Journal of the Korean Mathematical Society
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• v.35 no.1
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• pp.237-257
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• 1998

By introducing the notion of a generalized normal state space, we give a necessary and sufficient condition for that there exists a unital normal completely map from a von Neumann algebra into another, in terms of their generalized normal state spaces.

• Journal of Korean Academy of Nursing
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• v.13 no.1
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• pp.22-33
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• 1983

This study was done to research the relationship between State-Trait Anxiety and Sexual activity of pregnant women. The subjects for this study were 200 pregnant women from 2 hospitals located in a urban area. The data was collected through questionnaires which was developed by Spielberger, from to, 1982. The content of the questionnaire consist of following 2 categories of Anxiety and Sexual activity; (1) State Anxiety, (2) Trait Anxiety and (3) Sexual activity included sexual drive, number of sexual intercourse, and length of sexual intercourse. Analysis of data was done by use percentage, T-test, x$^2$-test, ANOVA and pearson correlation coefficiency. The findings of this study are as follows: 1. The mean score of state Anxiety and Trait Anxiety of respondents were 43.06, 44.19, therefore Trait Anxiety was higher than state Anxiety. 2. A significant state Anxiety and Trait Anxiety were not found among general characteristics with age, education level and religion 3. In the analysis of correlation among state Anxiety, Trait anxiety and Sexual activity, the Trait Anxiety was positively correlated with the State Anxiety. (r=.3877, p=.000) It was support the fact that the higher level of Trait anxiety, the greater was the State anxiety. 4. And the state anxiety was negatively correlated with number of sexual intercourse. (r=-1518, p=.016) Therefore, the higher the state anxiety, the lower sexual activity. Or the lower sexual activity, the higher the State Anxiety. 5. Also, in the analysis of factors affecting sexual activity, only the variable of age showed a significant correlation to number of sexual intercounse. That is the younger, the higher number of sexual intercounse. (r=. -. 1380, p=.026).

• The Transactions of the Korean Institute of Power Electronics
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• v.25 no.4
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• pp.303-310
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• 2020

Estimating the accurate internal state of lithium ion batteries to increase their safety and efficiency is crucial. Various algorithms are used to estimate the internal state of a lithium ion battery, such as the extended Kalman filter and sliding mode observer. A state-space model is essential in using algorithms to estimate the internal state of a battery. Two principal methods are used to express the state-space model, namely, continuous time and discrete time. In this work, the extended Kalman filter is employed to estimate the internal state of a battery. Moreover, this work presents and analyzes the estimation performance of algorithms consisting of a continuous time state-space model and a discrete time state-space model through static and dynamic profiles.

• The Bulletin of The Korean Astronomical Society
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• v.28 no.2
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• pp.57-57
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• 2003

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2020.10a
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• pp.96-96
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• 2020

• The Korean Journal of Ceramics
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• v.3 no.1
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• pp.18-20
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• 1997

The fabrication process of silicon-diamond(SOD) structure wafer were studied. Microwave plasma chemical vapor deposition (MWPCVD) and annealing technology were used to synthesize diamond film with high resistivity and thermal conductivity. Bonding and etchback silicon-on-diamond (BESOD) were utilized to form supporting substrate and single silicon thin layer of SOD wafer. At last, a SOD structure wafer with 0.3~1$\mu\textrm{m}$ silicon film and 2$\mu\textrm{m}$ diamond film was prepared. The characteristics of radiation for a CMOS integrated circuit (IC) fabricated by SOD wafer were studied.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.4
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• pp.339-347
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• 2022

This study proposes the mitigation method for overcurrent and oscillation motor current in an active short-circuit operation. This operation is attracting attention as the safe state of electric vehicle traction inverters. However, the active short-circuit operation generates oscillation and overcurrent of motor currents during a transient state. The proposed method uses two different safe states in PMSM, such as active short circuit and freewheeling. The active short circuit is used for safe state in a steady state. To reduce the overshoot and oscillation, a freewheeling state is injected between active short-circuit operation by comparing the motor phase current with an analytically calculated steady-state motor current. Freewheeling state is only used in a transient state. The performance is demonstrated through simulations and experimental results. The peak current of the motor was reduced from 52 A to 40 A, and oscillation time was reduced.

• Journal of applied mathematics & informatics
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• v.39 no.5_6
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• pp.805-811
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• 2021

Currently, batteries use commonly as energy sources for mobile electric devices. Due to the high density of energy, the energy storage state of a battery is very important information. To know the battery's energy storage state, it is necessary to find out the open state voltage of the battery. The open state voltage calculates with a mathematical model, but the computation of the real time state is complicated and requires many calculations. Therefore, the state observer designs to estimate in real time the battery open-circuit voltage as disturbance including model error. Using the estimated open voltage and applying it to the state estimation algorithm, we can estimate the charge. In this study, we first estimate the open-circuit voltage and design an estimation algorithm for estimating the state of battery charge. This includes errors in the system model and has a robust characteristic to noise. It is possible to increase the precision of the charge state estimation.

• Child Health Nursing Research
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• v.7 no.3
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• pp.298-307
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• 2001

This study assessed behavioral characteristics of 73 normal neonates in Daegu area using the NBAS. Being one of few studies on this topic, the study is to document and to accumulate data on the neonatal behaviors of Korean babies. Overall scores were at moderate levels in 6 behavioral clusters including Habituation, Social Interactive, Motor System, State Organization, and State Regulation. Autonomic Stability showed relative stableness. Scores of Orientation were higher in neonates of working mothers and rural mothers. Neonates of mothers with no abortion history have higher scores in Motor System and State Organization. Score of State Organization was higher in neonates of mothers with no habitual use of amenity during their pregnancy. Scores of Habituation and State Organization, as well as scores of Motor System with State Organization, State Regulation and Autonomic Stability were positively correlated. Scores of Habituation and State Organization indicate that babies are agreeable and even tameable that is advantageous for attachment to caregiver.