• The Journal of the Korean dental association
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• v.12 no.2
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• pp.107-111
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• 1974

In order to collect some necessary data to promote correcting the toothbrushing technic on the Korean public, the author had examined the number of present teeth on which had cervical abrasion and the most basic home dental care in 2,000 Korean male and female adults from 19 to 52 years in the age. Then, the cervical abrasion experience rate and the cervical abrasion experience teeth rate were calculated and evaluated. The obtained results were as follows: 1. Cervical abrasion experience rate was 32.45% 2. Cervical abrasion experience rate was gradually increased by ageing. 3. Cervical abrasion experience rate in male adults was higher than that in female adults. 4. Cervical abrasion experience rate in the lower jaw was higher than that in the upper jaw. 5. Cervical abrasion experience rate of the teeth at the right side was higher than that of the teeth at the left side. 6. Cervical abrasion experience teeth rate was 3.82%. 7. Cervical abrasion experience rate was highest on the first bicuspid, and followed in the sequence of the second bicuspid, canine, first molar, incisors, and 2nd and 3rd molars.

• Journal of the Korean Home Economics Association
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• v.49 no.8
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• pp.37-46
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• 2011

Using the 1987-2008 quarterly aggregated data of the Household Income and Expenditure Survey, this study investigated the factors influencing household saving rate. The independent variables in the AR regression model were the GDP growth rate, shares of the total household expenditure allocated to tax & social insurance, and education, the variables reflecting the conditions of the asset market including interest rate, stock market index, and real estate price index, and the variables representing the social economic conditions including the index of aging and income inequality. Among the independent variables interest rate, stock market index, and income inequality were found to be significantly associated with the household saving rate. These results suggested that the redistribution and financial market policies favorable to savers may be effective for raising the household saving rate.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.3
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• pp.125-130
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• 2020

At the end of 1997, the volatility of the exchange rate intensified as the nation's exchange rate system was converted into a free-floating exchange rate system. As a result, managing the exchange rate is becoming a very important task, and the need for forecasting the exchange rate is growing. The exchange rate prediction model using the existing exchange rate prediction method, statistical technique, cannot find a nonlinear pattern of the time series variable, and it is difficult to analyze the time series with the variability cluster phenomenon. And as the number of variables to be analyzed increases, the number of parameters to be estimated increases, and it is not easy to interpret the meaning of the estimated coefficients. Accordingly, the exchange rate prediction model using artificial neural network, rather than statistical technique, is presented. Using DNN, which is the basis of deep learning among artificial neural networks, and LSTM, a recurrent neural network model, the number of hidden layers, neurons, and activation function changes of each model found the optimal exchange rate prediction model. The study found that although there were model differences, LSTM models performed better than DNN models and performed best when the activation function was Tanh.

• International Commerce and Information Review
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• v.7 no.3
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• pp.269-286
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• 2005

The exchange rate volatility has been increased since the time when the floating exchange rate system was introduced in Korea. As a result, the increase of the exchange rate volatility raised the risk in international trades in Korea. The purpose of this study in to study the feature of exchange rate volatility and the main sources of its increase and to confirm whether the exchange rate volatility influence export volume and price of Korea. In the first place, I measured exchange rate volatility with two methods. The one is descriptive statistic method such as the width of daily exchange rate fluctuation and the rate of exchange rate devaluation. The other is the time varying conditional variance of exchange rate. Then, I studied the sources of exchange rate volatility. In the second place, I defined the exchange rate volatility as the time varying conditional variance and estimated it by using elastic a approach model which shows exchange rate is affected by itself and its conditional variance, I estimated its effects on export volumes and prices of electric home appliances, information & communication equal and semi-conductor. The result of this study is as follows. With presumed result EU and Korea because is not the goods which is to substantial competition relationship, The effect where the relative value change of presumed result expression anger and the dollar of import and export function goes mad to the import and export of Korea the income compared to is to export and it is appearing a lot. The EU goods is sold more expensively the Korean goods than from about length being caused by American market of the dollar and the balance of trade of Korea is visible like being visible the improvement of single breadth. Because the relationship of competition is weak but substantially there is to a short term and expression - the effect where the dollar rate fluctuation is big in Korean trade there is a possibility of saying that widely known it is not.

• Journal of the Korean Institute of Navigation
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• v.18 no.3
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• pp.31-49
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• 1994

In the meantime Korean Insurance Industry has been developed a steady growth under government's political protection. But insurance market seems to be opened unavoidably owing to the liberalization of international trade by the Agreements of UR and the bloc of economy by EC Integration and the Organization of NAFTA. By the above reason, especially, in case of hull insurance, the rate of hull insurance is being instituted as a problem. Accordingly the recognition for the problem like this, in thsi study, explained the major objectives of rate making and described the basic rate making methods that are used in property and liability insurance, and searched the rate making schemes of hull insurance rate of the major nations by comparing method. And as a conclusion, the writer presented several schemes including new rate making scheme of hull insurance rate and the security of statistical data about loss ratio, and the establishment of Korean Hull Insurance Association.

• International Journal of Advanced Culture Technology
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• v.7 no.1
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• pp.84-88
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• 2019

This paper examines whether the exchange rate respond differently to monetary policy shocks in Korea using regression model. We find an asymmetric response of the monetary policy shocks to the monetary policy shocks in the context of Korea. Over the whole period sample, we do not find the effect of an actual interest rate on exchange rate. But we find that the estimated coefficient on the expected and unexpected change in the policy rate are negative and statistically significant. In the period of monetary policy easing, the estimated coefficient on the expected and unexpected change in the policy rate are negative but not statistically significant. In contrast, the period of monetary policy tightening, the estimated coefficient on the expected and unexpected change in the policy rate are negative and statistically significant.

• Phonetics and Speech Sciences
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• v.6 no.3
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• pp.73-77
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• 2014

The purpose of this study is to investigate the differences of the speech rate according to the area in the perceptual and acoustic analysis. This study examines regional variation in overall speech rate and articulation rate across speaking situations (picture description, free conversation and story retelling) with 14 normal adult (7 in Gyeongnam and 7 in Honam area). The result of an experimental investigation shows that the perceptual speech rate differs significantly between two regional varieties of Koreans with a picture description examined here. A group of Honam speakers spoke significantly faster than a group of Gyeongnam speakers. However, the result of the acoustic analysis shows that the speech rate of the two groups did not differ. And there were significant regional differences in the overall speech rate and articulation rate on the other two speaking situation, free conversation and story retelling. It suggest that we have to study perceptual evaluation with regard to the free conversation and story retelling in future research, and based on the results of this study, a variety of researches on the speech rate will be needed on the various conditions, including various area and SLPs who have wider background and experiences. It is necessary for SLPs to train and experience more to assess patients properly and reliably.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.1044-1047
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• 2013

Wireless Mesh Network (WMN) provides effective Internet Service accesses to users by utilizing multi-rate and multi-channel. In multi-rate networks, the Rate Anomaly (RA) problem occurs, the problem that low-rate link degrades the performance of high-rate link. In this paper we propose Rate Gap Minimum Channel Assignment (RGM-CA) protocol that select the minimal rate gap parent node and assign the channel in order to mitigates the rate anomaly problem. RDM-CA protocol is efficient because it consider rate anomaly, channel diversity and node connectivity.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.45 no.2
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• pp.77-84
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• 2009

This paper is to investigate the effect of the immersion time in the traditional hairtail hand line for developing the fishing methods and the fishing gear in the coast of jeju. The operating of 32 times was made with each different immersion time of hairtail hand line, and the relations between the catch and the immersion time were examined. As the result, targeted species rate was over 98% of total catch. From about 800 seconds after casting, the hooking rate was decreased and the bite loss rate was increased, it seems to be made by the decreasing factors of predators including the cutting of branch lines etc. In addition, it was supposed that the hooking rate and the bait loss rate had a deep connection with feeding time zone. The level of the correlation coefficient of the bait loss rate according to the immersion time was 0.54 at $p{\leq}0.01$, in the case of the hooking rate, 0.59 was chosen after about 800 seconds. The hooking rate and the bait loss rate according to the hook number were not irrelevant to the fish school layer. Additionally, it was assumed that the bait loss rate was related to the depth of water.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.941-946
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• 2005

In this paper an active random noise control using adaptive learning rate neural networks is presented. The adaptive learning rate strategy increases the learning rate by a small constant if the current partial derivative of the objective function with respect to the weight and the exponential average of the previous derivatives have the same sign, otherwise the learning rate is decreased by a proportion of its value. The use of an adaptive learning rate attempts to keep the learning step size as large as possible without leading to oscillation. It is expected that a cost function minimize rapidly and training time is decreased. Numerical simulations and experiments of active random noise control with the transfer function of the error path will be performed, to validate the convergence properties of the adaptive learning rate Neural Networks. Control results show that adaptive learning rate Neural Networks control structure can outperform linear controllers and conventional neural network controller for the active random noise control.