• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.2
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• pp.81-95
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• 2014

In the present study, the statistical analysis on the storm waves in the East Sea have been carried out, and the several storm waves were reproduced by the modified WAM as a first step for the accurate and prompt forecasting and warning against the swell waves in East Sea. According to the present study, the occurrences of the storm waves from the North were the most probable, while the waves from the Northeast were most frequently observed. It was found that the significant wave heights of storm waves from the North and Northern northeast were larger than those of storm waves from the Northeast. But due to long fetch distance, the significant wave periods of storm waves from the Northesast were longer than those of North and Northern northeast. In addition to the wave analysis, the numerical experiments for the storm waves in East Sea were carried out using the modified WAM, and three periods of storm waves in 2013 were calculated. The numerical results were well agreed with wave measurements. However the numerical simulation results in shallow water region showed lower accuracies compared to deep water, which might be due to lower resolution of wind field and bottom topography caused by large grid size, 5 minute, adopted in the present study. Overall computational efficiency of the modified WAM found to be excellent compared to original WAM. It is because the modified WAM adopted the implicit scheme, thereby the present model performed 10 time faster than original WAM in computation time.

• The Journal of Engineering Geology
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• v.9 no.2
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• pp.119-134
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• 1999

Joints developed around the Moryang fault were investigated by traverse and inventory methods in order to characterize their orientation, spacing and density. The results of the traverse method show that the orientation of the dominant joint sets of the study area is NNE and EW, and that joint spacing distribution is a negative exponential distribution to the center of the fault and a log-normal distribution to the margin of the fault. The results of the inventory method show that the orientation of the dominant joint sets on joint map is NW and NE, and that joint density tends to increase toward the center of the fault. Fractal dimension was determined by using Box-counting method and Cantor's dust method to quantify the distribution of joint network and to evaluate the dimension around the fault. The dimension determined by Box-counting method ranges from 1.31 to 1.70 and shows the tendency of increasing value toward the center of the fault. Comparing fractal dimension by Box-counting method with joint density, fractal dimension is directly proportional to joint density. Nevertheless, fractal dimension could be varied due to the different distribution patterns of the joints with same density. The dimensions determined by Cantor's dust method show different values with respect to the orientation of scan lines. This results form the anisotropy of joint distribution.

• The Journal of the Petrological Society of Korea
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• v.26 no.3
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• pp.167-181
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• 2017

Cheongryangsan area ($49.51km^2$) has been designated as the Provincial Park in 1982, because it has magnificent aspect and seasonally spectacular landscapes. Especially, Cheongryangsa sitey ($4.09km^2$) has been designated as Noted Scenery No. 23 in 2007, because it has the same topographical landscape as rock cliffs, rock peaks and caves. The most spectacular landscapes are exhibited in the Cheongryangsan Conglomerate and Osipbong Basalt. There are twelve rock peaks on the ridges of the two strata, and many rock cliffs in the several valleys of strata, in which a few caves are formed by differential weathering and erosion. The valleys, in which flow Cheongryang, Bukgok and Cheonae streams, are classified as fault valleys along WNW-ESE faults. The rock cliffs were generated from vertical joints parallel to WNW-ESE faults in the two strata, and the caves were formed by differential weathering and erosion along bedding of sandstones and shales intercalated in the conglomerates. The rock peaks are landscapes formed by differential erosion along crossed vertical joints in the ridges. The vertical joints are developed subparallel to two WNW-ESE faults and a NNE-WWS fault. Therefore the topographical features are caused by existence of the faults and Lithologic difference in the Cheongryangsan Conglomerate and Osipbong Basalt, and by differential weathering and erosion along them.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.4
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• pp.233-257
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• 2023

Asbestos minerals are found at rocks and soils of the Hongseong and Bibong serpentine mines, western part of Chungnam. The area consists of and metasediment, and Mesozoic igneous intrusives with minor age-known gneiss complexes and Mesozoic sediments. With detailed geological investigations, rock samples for the serpentinite and amphibolite areas are collected at sites containing asbestos. Representative asbestos and rock samples are analysed by PLM, XRD, SEM and EPMA. Serpentinites are found as steeply dipping faults with adjacent gneiss complex to the NNE direction. Repeated alteration, including serpenitization and talcification, is found at the emplacement direction for the serpentinite body. Amphibollites occur as intrusives and stratiforms within the Precambrian gneiss complex. Serpentinite and amphibolite (or amphibole schist) contain amphiboles either as asbestiform or non-asbestiform. Varying amounts of asbestos minerals, including chrysotile, tremolite asbestos and actinolite asbestos, are found within the serpentinites. The asbestos minerals are found near the cracks or fractures and along the bedding plane. They occur as cross fiber, slip fiber and mass fiber types. Varying amounts of amphibole asbestos minerals, such as tremolite and actinolite asbestos, are found within amphibolites and as a mass fiber type. Overall results suggest that rocks of the serpentine mines contain serpentine and amphibole type asbestos minerals originated from the hydrothermal alteration. Considering construction nearby the mines and environmental risks by the asbestos, additional land management plans are required.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.4
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• pp.378-384
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• 2015

Indoor localization is becoming one of the most important technologies for smart mobile applications with different requirements from conventional outdoor location estimation algorithms. Fingerprinting location estimation techniques based on neural networks have gained increasing attention from academia due to their good generalization properties. In this paper, we propose a novel location estimation algorithm based on an ensemble of multiple neural networks. The neural network ensemble has drawn much attention in various areas where one neural network fails to resolve and classify the given data due to its' inaccuracy, incompleteness, and ambiguity. To the best of our knowledge, this work is the first to enhance the location estimation accuracy in indoor wireless environments based on a neural network ensemble using fingerprinting training data. To evaluate the effectiveness of our proposed location estimation method, we conduct the numerical experiments using the TGn channel model that was developed by the 802.11n task group for evaluating high capacity WLAN technologies in indoor environments with multiple transmit and multiple receive antennas. The numerical results show that the proposed method based on the NNE technique outperforms the conventional methods and achieves very accurate estimation results even in environments with a low number of APs.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.6
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• pp.99-121
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• 2002

Es ist eine $h\"{a}ufige$ Erscheinung, class das Verbreitungsgebiet einer Sprache mehrere $selbst\"{a}ndige$ Staaten umfasst, die an die verschiedene Gesellschafts- und Wirtschaftsszsteme angeschlossen werden und als die voneinander getrennte Kommunikationsgemeinschaften funktionieren. Aus diesem Aspekt kann die Frage gestellt werden, ob es in den versch:edenen deutschsprachigen Staaten zur Ausbildung von nationalen Varianten des Deutschen $k\"{a}me$. Aber um von nationalen Varianten gesprochen werden zu $k\"{o}nnen$, rechen nationale $Souveranit\"{a}t$, abweichendes Gesellschaftssystem und wenige lexikalische Besonderheiten jedenfalls nicht aus. $Daf\"{u}r\;m\"{u}sste$ ein Kriteriurn eines sprachlichen Normsystem noch erfullt werden. Es wird relativ leicht widerlegen lassen, dass die sprachlichen Besonderheiten in den deutschsprachigen Staaten zur Ausbildung einer nationalen Variante $f\"{u}hren$ sollten. Die Enteicklungstendenen des Deutschen $k\"{o}nne$ ein Vorbild $f\"{u}r$ die Betrachtung $\"{u}ber$ die Divergenz des Koreanischen sein. Aber systematische Analysen der nationalen Varianten im Koreanischen stehen leider noch aus. Somit muss intuitiv und $unvollst\"{a{ndig$ bleiben, was sich $\"{u}ber$ Besonderheiten der nationalen Varianten im Koreanischen sagen $l\"{a}sst$. Das ist noch eine zu $l\"{o}sende$ Aufgabe.

• Journal of the Korean earth science society
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• v.29 no.5
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• pp.437-445
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• 2008

We analyzed fault plane solutions of the recent twenty-two earthquakes which occurred from 2004 to 2006 in the central part of the Korean Peninsula by using P- and S-wave polarities along with SH/P amplitude ratios. The fault plane solution shows that strike-slip fault is dominant here, especially for the events with local magnitude equal to or greater than 3.0. However, some events with local magnitude less than 3.0 show normal fault or strike-slip fault with normal components. In the case of strike-slip fault, its orientation is almost in the direction of NNE-SSW to NE-SW almost parallel to the general trend of faults, while the compressional axis of the stress field trends ENE to E-W. The result is almost consistent with the stress field in and around the Korean peninsula, as reported previously. We cannot give any appropriate explanations to the normal faulting events along the western offshore and inland areas whether it is related to the local stress changes or tectonically unidentified extensional structures. Thus, an extension of investigations is desirable to clarify the cause of such phenomena.

• Proceedings of the Mineralogical Society of Korea Conference
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• 2002.10a
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• pp.17-30
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• 2002

삼척-도계지역 일대에 분포하는 조선누층군의 풍촌층 석회석은 품위 및 암상에따라 상부고품위대와 하부석회암대로 분대가 가능한데, 이는 삼척-태백간을 북북동으로 흐르는 오십천을 경계로 서쪽에 분포하는 풍촌층과 비교할 때 다소간의 암상차이를 보인다. 즉, 풍촌층의 특징중에 하나인 중부백운암대가 본 역 일대에서는 백운암화가 미약하여 비교적 소폭으로 확인되며, 상부백색대 역시, 발달정도가 미약한 특징을 보인다. 시추탐사결과 확인된 삼척-도계지역의 풍촌층 상부고품위대는 일반적으로 상부백색대$(\pm15m)$ - 백운암대$(\pm5m)$ - 암회색대$(\pm50m)$로 구분되는 것으로 나타났다. 각각의 품위는 상부백색대 : CaO $53_4\~55.6\%$, 백운암대 : MgO $3.0\~18.4\%$, 암회색대 : CaO $50.4\~54.2\%$로 나타나 제철용으로의 사용이 가능하나 백운암대에 대한 선별채광이 부분적으로 요망된다. 이들 석회석은 오십천대단층의 수반단층인 수조의 NNE계열 정단층들에 의해 빈번히 단절되어 있으며 일부지역에서는 EW향의 역단층에 의해 규제되기도 한다. 상기 제단층들은 석회암층을 단절시킬 뿐만 아니라 단층각력, 단층점토, 암맥 등의 불순대를 수반하므로 개발에 장애요소가 되고 있다. 상부고품위대 부존표고는 지역에 따라 다소 차이가 있으나 200ML 내외에서 대부분 확인이 가능하며 지표노출 규모는 작은 편이나 $10^{\circ}$이하의 완경사로 화절층 하부에 부존되어 있어 갱도 채광에 적합한 형태를 이루고 있다.

• Speech Sciences
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• v.8 no.2
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• pp.39-48
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• 2001

The purpose of this study was to examine changes in acoustic characteristics after drinking alcoholic beverages and singing in order to establish guidelines for vocal hygiene of both singers and non-singers. 21 university students (10 males and 11 females) vocalized /a/ before drinking, after drinking and after singing. Changes in vocal range and acoustic characteristics were analyzed by Dr. Speech 4.0 (Tigers Electronics). No significant difference was observed in vocal range following drinking. However, there was statistically significant changes in vocal range after singing. We may infer that appropriate amount of singing functioning as vocal warm-up, rather than drinking alone, resulted in improvement in their abilities to lengthen vocal folds. This is directly related to the ability to produce high-pitched sounds. Changes in jitter in female voices after singing was the only acoustic factor that was significant. Changes in Shimmer and NNE was not significant either after drinking nor singing. Subjects who were judged to perform better in singing were marked by minimum acoustic changes, which may due to their well-trained vocal fold function. The results of this study may address the necessity for vocal function exercises for the patients with neurogenic voice disorders including dysarthria. The need for more extensive research with a larger number of subjects including professional voice users is also addressed.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.516-518
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• 1999

This paper presents an feed-forward neural network design instead PI controller for the speed control of an Induction Motor. The design employs the training strategy with Neural Network Controller(NNC) and Neural Network Emulator(NNE). Emulator identifies the motor by simulating the input and output map. In order to update the weights of the Controller. Emulator supplies the error path to the output stage of the controller using backpropagation algorithm. and then Controller produces an adequate output to the system due to neural networks learning capability. Therefore it becomes adjustable to the system with changing characteristics caused by a load. The speed control based on neural networks for induction motor is implemented by a vector controlled induction motor. The simulation results demonstrate that actual motor speed with neural network system well follows the reference speed minimizing the error and is available to implement on the vector control theory.