• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 춘계학술대회 논문집
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• pp.247-253
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• 2004

As a large scale port development in coastal waters proceeds step by step and populations in the vicinity of port are getting increased, the issue on "how to dispose the treated municipal water and wastewater in harbor" brings peoples′ concern. The submarine outfall system discharges the primary or secondary treated effluent at the coastline or in deep water, or between these two. The effluent, which has a density similar to that of fresh water, rises to the sea surface forming plume or jet, together with entraining the surrounding sea water and becomes very dilute. We intended in this paper to investigate the impact on dilution of effluent and the behavior of flume under the conditions of the seasonal and spatial temperature variations, which have not been noticeable in designing effective marine outfall system. To predict and analyze the behaviour and dilution characteristics of plume not just with the effluent temperature, but also with the seasonal variation of temperature of surround water and tidal changes, CORMIX(Cornell Mixing Zone Expert System)-GI have been applied. The results should be used with caution in evaluation the mixing zone characteristics of discharged water. We hope to help for the effective operation of outfall system, probable outfall design, protection of water quality, and warm water discharges from a power plant, etc.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.104-104
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• 2010

With the advent of nano-particle fillers in insulating materials, the insulating materials of superior quality have come to fore. In the recent past, nanocomposite LDPE/XLPE (Low Density Polyethylene/Cross Linked Polyethylene) power cable dielectrics have been synthesized. A preliminary evaluation of these new class of materials seem to show that, addition of small amounts of sub-micron inorganic fillers improved the dielectric properties of the composite, in particular, the volume resistivity, and the DC breakdown strength. The thermal behaviour, for example, the stability of composites against decomposition and ensuing electrical failure, do not seem to have been addressed. In a conventional XLPE insulated cable, the average thermal breakdown strength and maximum temperature at the onset of breakdown were seen to be markedly lower than the corresponding intrinsic breakdown strength and decomposition temperature. In this page, analysis of DC Breakdown of nano-composite insulating material for HVDC Cable is introduced.

• Earthquakes and Structures
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• 제3권6호
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• pp.889-910
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• 2012

Because of the heavy demand of confining steel to restore the column ductility in seismic regions, it is more efficient to confine these columns by hollow steel tube to form concrete-filled-steel-tube (CFST) column. Compared with transverse reinforcing steel, steel tube provides a stronger and more uniform confining pressure to the concrete core, and reduces the steel congestion problem for better concrete placing quality. However, a major shortcoming of CFST columns is the imperfect steel-concrete interface bonding occurred at the elastic stage as steel dilates more than concrete in compression. This adversely affects the confining effect and decrease the elastic modulus. To resolve the problem, it is proposed in this study to use external steel confinement in the forms of rings and ties to restrict the dilation of steel tube. For verification, a series of uni-axial compression test was performed on some CFST columns with external steel rings and ties. From the results, it was found that: (1) Both rings and ties improved the stiffness of the CFST columns and (2) the rings improve significantly the axial strength of the CFST columns while the ties did not improve the axial strength. Lastly, a theoretical model for predicting the axial strength of confined CFST columns will be developed.

• 아동학회지
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• 제35권4호
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• pp.123-143
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• 2014

This research was based on achievement goal theory which categorizes young children's motivation into three types: mastery, the performance-approach, and performance-avoidance motivation. The participants consisted of forty-eight pairs of children aged 3-4 and their mothers. The participants completed two tasks in order to indentify their motivational types. The short form of the Child Behaviour Questionnaire(CBQ-SF), modified scales from Kim and Kim(2001), and the GIPEPS were also employed. The major findings of the research are as follows: First, in terms of the motivational types of the given sample, performance-approach motivation was ranked first followed by mastery motivation. Second, it was found that the temperament of young children was not related with their motivational types. Third, there were some differences in mother-child interaction between groups based on the frequency of feedback, questions, and the percentage of commands. Fourth, the mood of the relationship appeared to be the only factor of maternal interaction quality which related to children's mastery motivation.

• 대한전기학회논문지:전력기술부문A
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• 제48권2호
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• pp.107-114
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• 1999

This paper presents an application of artificial neural networks(ANN) to assess the dynamic security of power systems. The basic role of ANN is to provide assessment of the system's stability based on training samples from off-line analysi. The critical clearing time(CCT) is an attribute which provides significant information about the quality of the post-fault system behaviour. The function of ANN is a mapping of the pre-fault, fault-on, and post-fault system conditions into the CCT's. In previous work, a feed forward neural network is used to learn this mapping by using the generation outputs during the fault as the input data. However, it takes significant calculation time to make the input data through the network reduction at a fault as the input data. However, it takes significant calculation time to make the input data through the network reduction at a fault considered. In order to enhance the speed of security assessment, the bus data and line powers are used as the input data of the ANN in thil paper. Test results show that the proposed neural networks have the reasonable accuracy and can be used in on-line security assenssment efficiently.

• 한국분말재료학회지
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• 제14권6호
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• pp.362-366
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• 2007

Magnesium and magnesium alloys are promising materials for light weight and high strength applications. In order to obtain homogeneous and high quality products in powder compaction and powder forging processes, it is very important to control density and density distributions in powder compacts. In this study, a model for densification of metallic powder is proposed for pure magnesium. The mode] considers the effect of powder characteristics using a pressure-dependent critical density yield criterion. Also with the new model, it was possible to obtain reasonable physical properties of pure magnesium powder using cold iso-state pressing. The proposed densification model was implemented into the finite element method code. The finite element analysis was applied to simulating die compaction of pure magnesium powders in order to investigate the density and effective strain distributions at room temperature.

• 수산해양교육연구
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• 제28권4호
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• pp.1143-1151
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• 2016

To study the dispersion process and residence time of anthropogenic pollutant in Masan bay, a three-dimensional hydrodynamic model coupled to a particle tracking model, EFDC, is applied. Particle tracking model simulated the instantaneous release of particles emulating discharge from river and wastewater treatment plant to show the behaviour of pollutant in terms of water circulation and water exchange. Modelled outcomes for water circulation were in good agreement with tidal elevation and current data. The results of particle tracking model show that over half of particles released from northern Masan bay transport to out of area while the particles from Dukdong wastewater treatment plant transport to northern area. This meant pollution source from inside and outside of the northern area can affect water quality of northern Masan bay.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.92-96
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• 2004

The researches of the emotions are currently great interest in speech processing as well as in human-machine interaction domain. In the recent years, more and more of researches relating to emotion synthesis or emotion recognition are developed for the different purposes. Each approach uses its methods and its various parameters measured on the speech signal. In this paper, we proposed using a short-time parameter: MFCC coefficients (Mel­Frequency Cepstrum Coefficients) and a simple but efficient classifying method: Vector Quantification (VQ) for speaker-dependent emotion recognition. Many other features: energy, pitch, zero crossing, phonetic rate, LPC... and their derivatives are also tested and combined with MFCC coefficients in order to find the best combination. The other models: GMM and HMM (Discrete and Continuous Hidden Markov Model) are studied as well in the hope that the usage of continuous distribution and the temporal behaviour of this set of features will improve the quality of emotion recognition. The maximum accuracy recognizing five different emotions exceeds $88\%$ by using only MFCC coefficients with VQ model. This is a simple but efficient approach, the result is even much better than those obtained with the same database in human evaluation by listening and judging without returning permission nor comparison between sentences [8]; And this result is positively comparable with the other approaches.

• 복식
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• 제59권8호
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• pp.110-122
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• 2009

The objective of this study is to suggest a direction eco-friendly material based fashion products may pursue in the 21 st century in order to protect our environment. This is done by considering the knowledge of the products by housewives, the main consuming players in a household. 398 copies of the survey were collected amongst Korean and Japanese housewives in the 30s and 40s aged group sample and analysed using SPSS 12.0 statistic program. The analysis results are as follows. First, base material was highly knew by Koreans in contradiction with Japanese who were highly knowing the disposal process in regard to eco-friendly fashion products. Second, a higher ratio of Koreans tended to purchase the product with consideration of health issues, however quality of the material was considered more by Japanese buyers. Finally, the result showed that eco-friendly products buyers from both countries had more willingness to purchase eco-friendly material based fashion products than non-buyers in the future. Korean housewives showed more interest in environment, benefit to health and value from eco-friendly material based fashion products than Japanese. Koreans had a better understanding of information and knowledge of the product, as well as higher future purchase intention however, Koreans considered less durability, design and variety of products.

• 한국해안해양공학회지
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• 제5권1호
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• pp.19-24
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• 1993

슈퍼컴과 워크스테이션을 사용하여 해양과정의 모델링 결과를 고화질의 컴퓨터 영상으로 제시할 수 있게 되었다. 본 연구에서는 근년에 발생한 지진진파(쯔나미)에 대한 수치모형을 적용하여 산정된 수위를 3차원적으로 연속적인 동화로서 제시하였다. 이 결과 광원, 반사 및 음영을 나타내는 최신 렌더링 기법에 의한 사진과 같은 효과를 갖는 영상들을 구축하였다. 비디오동화에 의한 수치모형의 결과는 실제적인 쯔나미의 파급거동을 잘 제시하였다.