• Structural Engineering and Mechanics
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• v.82 no.4
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• pp.445-458
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• 2022

Some of the control systems used in engineering structures that use sensors and decision systems have some time delay reducing efficiency of the control system or even might make it unstable. In this research, in addition to considering the effect of the time delay in vibration control process, predictive control is used to compensate the time delay. A semi-active vibration control approach with the help of magneto-rheological dampers is implemented. In addition to using fuzzy inference system to determine the appropriate control voltage for MR damper, structural behavior prediction system and specifying future responses are also used such that the time delays occurring within control process are overcome. For this purpose, determination of prediction horizon is conducted for one, five, and ten steps ahead for single degree of freedom structures with periods ranging from 0.1 to 4 seconds, subjected to twenty earthquake excitations. The amount of time delay applied to the control system is 0.1 seconds. The obtained results indicate that for 0.1 second time delay, average prediction error values compared to the case without time delay is 3.47 percent. Having 0.1 second time delay in a semi-active control system reduces its efficiency by 11.46 percent; while after providing the control system with structure behavior prediction, the difference in the results for the control system without time delay is just 1.35 percent on average; indicating a 10.11 percent performance improvement for the control system.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.8 no.1
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• pp.31-36
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• 2008

This paper presents adaptive learning data of evolvable neural networks (ENNs) for time series prediction of nonlinear dynamic systems. ENNs are a special class of neural networks that adopt the concept of biological evolution as a mechanism of adaptation or learning. ENNs can adapt to an environment as well as changes in the enviromuent. ENNs used in this paper are L-system and DNA coding based ENNs. The ENNs adopt the evolution of simultaneous network architecture and weights using indirect encoding. In general just previous data are used for training the predictor that predicts future data. However the characteristics of data and appropriate size of learning data are usually unknown. Therefore we propose adaptive change of learning data size to predict the future data effectively. In order to verify the effectiveness of our scheme, we apply it to chaotic time series predictions of Mackey-Glass data.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.920-924
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• 2005

This paper presents adaptive learning data of evolvable neural networks (ENNs) for time series prediction of nonlinear dynamic systems. ENNs are a special class of neural networks that adopt the concept of biological evolution as a mechanism of adaptation or learning. ENNs can adapt to an environment as well as changes in the environment. ENNs used in this paper are L-system and DNA coding based ENNs. The ENNs adopt the evolution of simultaneous network architecture and weights using indirect encoding. In general just previous data are used for training the predictor that predicts future data. However the characteristics of data and appropriate size of learning data are usually unknown. Therefore we propose adaptive change of learning data size to predict the future data effectively. In order to verify the effectiveness of our scheme, we apply it to chaotic time series predictions of Mackey-Glass data.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.230-233
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• 2001

Revision of KS, Korean Standards, is currently actively discussed. It is just the time for a new world class standards under the new system with WTO, World Trade Organization. This paper is a part of "Researches on the Standards in the Building Acoustic Field", as one of KS revision projects. The aim of this study is to define the requirements for measuring the reverberation time of rooms with reference to other acoustical parameters. In the former KS, there is no items matched with this purpose. Therefore measuring reverberation time and other room acoustical parameters with confidential test procedure was impossible. On these basis, a new part of KS is proposed, and some problems remained and further discussions in the proposed draft are described in this study.

• The Journal of the Korean dental association
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• v.53 no.10
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• pp.696-704
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• 2015

The coverage of the National Health Insurance for the elderly is expanding to denture and implants. Although the National Long-Term Care Insurance was just being settled, Oral health service was not provided to the Elderly in Long-Term Care Facilities. The long-term care facilities had part-time facility doctors. However, there is no dentist in the long-term care facility because of lack of long-term care insurance-related legislations. The amendments of long-term care insurance-related legislations for the introduction of part-time facility dentists are needed because the elderly in long-term care facility are vulnerable to oral health. For the substantial management of the National Long-Term Care Insurance, the development of oral health service model for the elderly and education materials for the dental team will be needed. Also, adequate dental service fee of the National longterm care insurance will be needed.

• Women's Health Nursing
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• v.7 no.1
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• pp.30-43
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• 2001

This was a pre-experimental study to confirm the breast-feeding ability and effect of follow up care on the breast-feeding rate and the breast-feeding method by the mother-infant breast-feeding assessment tool for the mothers who got the breast-feeding education. The subjects were 46 mothers who experienced normal delivery of infants at a college hospital in K-city, Kyungsangbuk-do, from July 1 to October 21, 2000. The instrument for data obtainment were The Mother-Infant Breast-Feeding Assessment Tool of Johnson et al. (1999), and The Breast- Feeding Method Measurement Tool of Jeong, Geum-hee(1997). This instrument was reliable, showing Cronbach $\alpha$.751. This study classified them into 3 groups: at high risk for breast-feeding failure, at risk for breast-feeding problems, and at low risk for breast-feeding failure by the mother-infant breast-feeding assessment tool on the day of discharge from the hospital after delivering individual breast-feeding education to the subjects. This study investigated the breast-feeding rate and the breast-feeding method through mail questionnaire at the four week after childbirth, and through the phone counselling and the home visit for follow up care at the first week and the second week after childbirth. The sixth week after childbirth, this study investigated the breast-feeding rate by phone. The data analyzed the hypothesizes by $x^2$-test, paired t-test, ANOVA, Wilcoxon signed rank test, Wilcoxon rank sum test and trend analysis using SPSS/PC+ WIN 10.0 program. The results were as follows : 1) Hypothesis 1-1, "there won't be any difference the breast-feeding rate of a group at risk for breast-feeding failure by the time elapsed" was supported through constant the breast-feeding rate, because changes in the breast-feeding rate by the time elapsed after childbirth wasn't statistically significant(t= -1.501, p=.270). Hypothesis 1-2, "there won't be any difference the breast-feeding rate of group at low risk for breast-feeding failure by the time elapsed" was supported through constant the breast-feeding rate, because changes in the breast-feeding rate by the time elapsed after childbirth wasn't statistically significant(t=-1.732, p=.225). 2) Hypothesis 2-1, "there won't be any difference between the breast-feeding method of group at risk for breast-feeding failure for four weeks after childbirth and just after childbirth” was rejected, because the mean point of post test appeared to be higher than that of pre test(t=-7.267, p=.000). Hypothesis 2-2, "there won't be any difference between the breast-feeding method of the group at low risk for breast-feeding failure for four weeks after childbirth and just after childbirth" was rejected, because the mean point of post test appeared to be higher than that of pre test(t=-2.501, p=.012). 3)The 3rd hypothesis, "there won't be any difference between breast-feeding method of groups at risk for breast-feeding problems and at low risk for breast-feeding failure at the 4th week after childbirth and just after childbirth" didn't show any difference between the breast-feeding method of groups at risk for breast-feeding problems and at low risk for breast-feeding failure in the advance test(t=-1.521, p=.130) but there was difference between them in post test (t=-2.012, p=.044). As a result, the 3rd hypothesis was supported by pre test, but it was rejected by post test. In conclusion, this study confirmed breast- feeding education and follow up care just after childbirth were effective for the breast-feeding rate and method. Accordingly, it is proposed that successful nursing intervention of breast-feeding to be necessary by continuously providing follow up care through the mother-infant breast-feeding assessment tool as well as to execute individual breast-feeding education to mothers just after childbirth.

• Journal of KIISE:Software and Applications
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• v.37 no.7
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• pp.584-589
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• 2010

The dynamic time warping algorithm generally used in time series pattern recognition spends most of the time in generating the correlation table, and it establishes the global path constraint to reduce the corresponding time complexity. However, the constraint restrains just in terms of the time axis, not considering the contents of input patterns. In this paper, we therefore propose an efficient branch and bound dynamic time warping algorithm which sets the global constraints by adaptively reflecting the patterns. The experimental results show that the proposed method outperforms conventional methods in terms of the speed and accuracy.

• Korean Journal of Construction Engineering and Management
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• v.2 no.1 s.5
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• pp.88-97
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• 2001

The Internet, the main issue of a new millennium, is being researched vitally for the progress of the construction industry, and the construction industry is considered to be led into a high-value added state-of-arts technology industry through CALS. Even if many construction companies gradually widen the use of the Internet for various purposes such as an electronic bidding system and an e-commerce system, the companies are still demanded to use the Internet more broadly and practically. Hence, the need for a tool for fast decision making and an effective construction management has risen. The PRIMA system has been developed specifically focused on meeting with those recent changes of the construction industry. This system is composed of three parts. Those are Just In Time(JIT) management, integrated application of man power${\cdot}$safety${\cdot}$work management and decision making process based on real-time information in the Internet. The usefulness of the PRIMA system has already been proved in a super-scale construction project. As the Internet environment get improved the use of the tool will be spread out gradually for many construction projects, regardless their size and location.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.37-39
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• 2009

In the research of speech recognition, locating the beginning and end of a speech utterance in a background of noise is of great importance. Since the background noise presenting to record will introduce disturbance while we just want to get the stationary parameters to represent the corresponding speech section, in particular, a major source of error in automatic recognition system of isolated words is the inaccurate detection of beginning and ending boundaries of test and reference templates, thus we must find potent method to remove the unnecessary regions of a speech signal. The conventional methods for speech endpoint detection are based on two simple time-domain measurements - short-time energy, and short-time zero-crossing rate, which couldn't guarantee the precise results if in the low signal-to-noise ratio environments. This paper proposes a novel approach that finds the Lyapunov exponent of time-domain waveform. This proposed method has no use for obtaining the frequency-domain parameters for endpoint detection process, e.g. Mel-Scale Features, which have been introduced in other paper. Comparing with the conventional methods based on short-time energy and short-time zero-crossing rate, the novel approach based on time-domain Lyapunov Exponents(LEs) is low complexity and suitable for Digital Isolated Word Recognition System.

• Journal of Biosystems Engineering
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• v.14 no.1
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• pp.8-15
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• 1989

Agricultural materials do not react in a purely elastic manner, and their responses when subjected to stress and strain are appeared from a combination of elastic and viscous behavior. Various researchers have studied the mechanical and rheological properties of the many agricultural materials, but those properties are available mostly foreign varieties of agricultural products. Rheological properties of rice seedlings become important to formulate the principles governing their mechanical behavior. The objectives of this study were to experimentally determine the stress relaxation properties of rice seedlings such as three Japonica-type and one Indica ${\times}$ Japonica hybrid in the transplanting age. The results of this study are summarized as follows; 1. The stress relaxation behavior could be described by the generalized Maxwell model. 2. The phenomenon of stress relaxation happened abruptly just after loading and this phenomenon weakened with the loading time lapsed. 3. With increase of the initial stress, the stress relaxation intensity and residual stress increased, while the relaxation time was constant with increased, while the relaxation time was constant with increase of the level of initial stress. 4. With increase of loading rate, the stress relaxation intensity increased, while the relaxation time and residual stress decreased.