• Journal of Hydrogen and New Energy
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• v.32 no.5
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• pp.324-330
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• 2021

In recent years, polymer electrolyte membrane fuel cell (PEMFC) based cogeneration system has received more and more attention from energy researchers because beside electricity, the system also meets the residential thermal demand. However, the low-quality heat exited from PEMFC should be increased temperature before direct use or storage. This study proposes a method to utilize the heat exhausted from a 10 kW PEMFC by coupling a heat pump. Two different configuration using heat pump and a reference layout with heater are analyzed in term of thermal and total efficiency. The system coefficient of performance (COP) increases from 0.87 in layout with heaters to 1.26 and 1.29 in configuration with heat pump and cascade heat pump, respectively. Lastly, based on system performance result, another study in economics point of view is proposed.

• Spatial Information Research
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• v.20 no.2
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• pp.59-70
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• 2012

Advances in science and technology, especially the increasing popularity of smart phone has opened up infinite possibilities for the information retrieval. And the augmented reality technology which has started getting attention to various fields has allowed us to get an information in an innovative way by providing additional information to a real world before our eyes. The purpose of this study is to suggest and to construct mobile application service which give history-tourism information efficiently based on augmented reality technology. As a result of study, we suggest that it is needed to find the view point that the most accurate information can be provided to the users according to each contents such as maps, pictures, drawings etc. and to provide the function to the users which shows the view points information efficiently. The purpose of this study is to investigate the possibility whether the technology studied in private sector by using augmented reality based on smart phone can also be applied in public sector for the service of history tourism information. We expect that this study can be the basis for providing the more advanced augmented reality service in the near future.

• Journal of the Korean Society of Costume
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• v.14
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• pp.167-183
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• 1990

As an attempt to view Chason costume from a aesthetic perspective, the aesthetic values of the Choson people, as expressed through the aesthetic characteristics of costumes, are pursued in this study. To appreciate the beauty of the traditional Korean costume, the following aesthetic characteristics of Choson costumes are investigated: form, color, pattern, material and ornament. From the view point of aesthetics, this study shows that Choson costume had comfortable and voluminous forms with beautiful curved lines and rhythm. The most favored colors were white and natural colors of materials. However unusual combination of colors such as the contrast of black and white, the harmony of the primary and rainbow colors were often used. Patterns revealed two aspects : while subdued patterns generally prevail, at times the unexpected beauty of primary colored patterns draws our attention. Smooth natural materials were preferred. Ornaments both for practical and decorative purposes were used together with certain colors and patterens, indicating wearer's status and warding off the evil's spirits. The aesthetic values in costumes as expressed through the aesthetic characteristics can be classified into the following categories: the beauty of nature, the beauty of personality, the aesthetics of evil's eye and the beauty of tradition. The beauty of nature, as appreciated by the Chason people through their prevailing nature, the "Pung-rew Spirit" and through their Worship of Heaven, produced aesthetic characteristics in harmony with nature. The beauty of personality influenced by the ethical standard of Confucianism produced aesthetic characteristics in costumes, through which the appropriate personality was shown for the appropriate social status. On the other hand, the aesthetics of evil's eye, rooted deeply in Folk religion and Shamanism, contributed to various aesthetic characteristics, which strongly inclined to sorcery and symbolism through choice of patterns, colors and ornaments. Finally, the beauty of tradition, which was based on the ethics of Confucianism and the Choson people's conservative tendencies, demonstrated the strong tendency to adhere to the external characteristics of the Choson costume. These aesthetic values were the yardsticks of the aesthetic judgment of the Choson people. These values influenced Chason people in designing costumes and in appreciating the beauty of costumes. The aesthetic experience and attitudes of the Chason people, which were based on these aesthetic values, represented their aesthetic consciousness and desires.

• Journal of the Korean Society of Costume
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• v.58 no.2
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• pp.134-148
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• 2008

Methods of delivering products to consumers do not act as less important factor than creative activities to create new product designs. Mobilizing various psychological elements based on human instinct and desire, fashion industry presents a product as an object of envy, gaining viewers' attention. Here, the viewer does not simply take the product as an object to view, but also imagine transformation it will bring. The study of the cause and effects of the interaction, which is found in the relationship between "the viewer" and "what is viewed" is an important factor that needs to be identified in the phase of creation as well as in the aspect of delivery. The relationship between the perceiver and what is perceived features in designs, product advertisements, related articles, and fashion shows in modern fashion, serving as a medium that enables the humans, who must inevitably exist between the two poles such as mind and body, the subject and the object, the ego and non-ego, and the reality and an ideal, to communicate between the poles. Humans cannot do arbitrary acts or make arbitrary selections only as they access to foreign things through instinct, desire, or experienced perception, and they are sometimes positioned passive by things. In the background, as there are human dual characteristics in which they are expressed as the ego and another ego who exists inside of the ego, they not only view an object, but also become an object to be viewed. Many products in modern fashion, as the objects of reciprocal transposition, grow giving illusions to humans. Having a desire for such objects is human's instinct and normal act to keep the life balanced between the reality and an ideal, which is based on the activation of reality function. Furthermore, freely acting rather than ignoring or overcoming the desire may be the act of retrieving one's ownership to the ego.

• Ceramist
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• v.23 no.1
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• pp.16-26
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• 2020

Recently, polymer-metal composite (IPMC)-based ionic artificial muscle has been drawing a huge attention for its excellent soft actuator performance having outstanding soft actuator performance with efficient conversion of electrical energy to mechanical energy under low working voltage. In addition, light, flexible and soft nature of IPMC and high bending strain response enabled development of versatile sensor application in association with soft actuator. In this paper, current issues of IPMC were discussed including standardizing preparation steps, relaxation under DC bias, inhibiting solvent evaporation, and improving poor output force. Solutions for these drawbacks of IPMC have recently been suggested in recent studies. After following explanation of the IPMC working mechanism, we investigate the main factors that affect the operating performance of the IPMC. Then, we reviewed the optimized IPMC actuator fabrication conditions especially for the preparation process, additive selection for a thicker membrane, water content, solvent substitutes, encapsulation, etc. Lastly, we considered the pros and cons of IPMCs for sensor application in a theoretical and experimental point of view. The strategies discussed in this paper to overcome such deficiencies of IPMCs are highly expected to provide a scope for IPMC utilization in soft robotics application.

• KIEE International Transactions on Power Engineering
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• v.3A no.4
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• pp.214-221
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• 2003

In view of the fact that gas insulated switchgear (GIS) is an important piece of equipment in a substation, it is highly desirable to continuously monitor the state of equipment by measuring the partial discharge (PD) activity in a GIS, as PD is a symptom of an insulation weakness/breakdown. However, since the PD signal is relatively weak and the external noise makes detection of the PD signal difficult, it therefore requires careful attention in its detection. In this paper, the algorithm for detection of PD in the GIS using the wavelet transform (WT) is proposed. The WT provides a direct quantitative measure of the spectral content and dynamic spectrum in the time-frequency domain. The most appropriate mother wavelet for this application is the Daubechies 4 (db4) wavelet. 'db4', the most commonly applied mother wavelet in the power quality analysis, is very well suited to detecting high frequency signals of very short duration, such as those associated with the PD phenomenon. The proposed algorithm is based on utilizing the absolute sum value of coefficients, which are a combination of D1 (Detail 1) and D2 (Detail 2) in multiresolution signal decomposition (MSD) based on WT after noise elimination and normalization.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.810-815
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• 1988

This paper presents a mobile robot that travels employing visual information. The mobile robot is equipped solely with a TV camera as a sensor, and views from the TV camera are transferred to a separately installed micro computer through an image acquisition device. An acquired image of a view is processed there and the information necessary for travel is yielded. Instructions based on the information are then sent from the micro computer to the mobile robot, which causes the mobile robot next action. Among several application programs that have already been developed for the mobile robot other than the entire control program, this paper focuses its attention on the travelling control of the mobile robot in a model environment with obstructions as well as an overview of the whole system. The behaviour the present mobile robot takes when it travels among obstructions was investigated by an experiment, and satisfactory results were obtained.

• Journal of the Ergonomics Society of Korea
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• v.29 no.1
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• pp.145-153
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• 2010

Activity of lifting has been a major issue in many research area related in manual materials handling tasks. However, the opposite activity of lifting, lowering, has received much less attention. It is known that 52% of all box-handling tasks were lowering in nature. The difference in stress between lifting and lowering activity is not well understood. A simple assumption that these two activities are very similar has been established and widely used. However, this simple assumption may be questionable. The objective of this study was to compare a lifting activity and a lowering activity based on the three different ergonomic approaches; (1) biomechanical, (2) physiological, (3) psychophysical approach. It was found that the stress of lowering activity was from 65% to 93%, from 87% to 97%, and from 87% to 96% according to the biomechanical, physiological, and psychophysical point of view, respectively. It is concluded from the result of this study that the stress of lowering activity is lower than that of the lifting activity. The maximum compressive force on the lumbro-sacral joint (L5/S1) was 158% and 108% respectively, for lifting and lowering activity of which the work load is the 58% of Action Limit. It is suggested that the NIOSH AL and RWL and biomechanical criteria should be reconsidered especially for the low frequency of lifting activities.

• Journal of Information Processing Systems
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• v.9 no.4
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• pp.602-620
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• 2013

Many previous research studies on extractive text summarization consider a subset of words in a document as keywords and use a sentence ranking function that ranks sentences based on their similarities with the list of extracted keywords. But the use of key concepts in automatic text summarization task has received less attention in literature on summarization. The proposed work uses key concepts identified from a document for creating a summary of the document. We view single-word or multi-word keyphrases of a document as the important concepts that a document elaborates on. Our work is based on the hypothesis that an extract is an elaboration of the important concepts to some permissible extent and it is controlled by the given summary length restriction. In other words, our method of text summarization chooses a subset of sentences from a document that maximizes the important concepts in the final summary. To allow diverse information in the summary, for each important concept, we select one sentence that is the best possible elaboration of the concept. Accordingly, the most important concept will contribute first to the summary, then to the second best concept, and so on. To prove the effectiveness of our proposed summarization method, we have compared it to some state-of-the art summarization systems and the results show that the proposed method outperforms the existing systems to which it is compared.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.12
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• pp.5955-5977
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• 2018

Performance of the interpolation algorithm used in the technique of bi-dimensional empirical mode decomposition directly affects its popularization and application, so that the researchers pay more attention to the algorithm reasonable, accurate and fast. However, it has been a lack of an adaptive interpolation algorithm that is relatively satisfactory for the bi-dimensional empirical mode decomposition (BEMD) and is derived from the image characteristics. In view of this, this paper proposes an image interpolation algorithm based on the particle swarm and fractal. Its procedure includes: to analyze the given image by using the fractal brown function, to pick up the feature quantity from the image, and then to operate the adaptive image interpolation in terms of the obtained feature quantity. All parameters involved in the interpolation process are determined by using the particle swarm optimization algorithm. The presented interpolation algorithm can solve those problems of low efficiency and poor precision in the interpolation operation of bi-dimensional empirical mode decomposition and can also result in accurate and reliable bi-dimensional intrinsic modal functions with higher speed in the decomposition of the image. It lays the foundation for the further popularization and application of the bi-dimensional empirical mode decomposition algorithm.