• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.6 s.237
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• pp.737-746
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• 2005

The present study investigates heat/mass transfer and flow characteristics in a ribbed rotating passage with turning region. The duct has an aspect ratio (W/H) of 0.5 and a hydraulic diameter ($D_h$) of 26.67 mm. Rib turbulators are attached in the cross arrangement on the leading and trailing surfaces of the passage. The ribs have a rectangular cross section of $2\;mm\;(e){\times}\;mm\;(w)$ and an attack angle of $70^{\circ}$. The pitch-to-rib height ratio (p/e) is 7.5, and the rib height-to-hydraulic diameter ratio ($e/D_h$) is 0.075. The rotation number ranges from 0.0 to 0.20 while the Reynolds number is constant at 10,000. To verify the heat/mass transfer augmentation, internal flow structures are calculated for the same conditions using a commercial code FLUENT 6.1. The heat transfer data of the smooth duct for various Ro numbers agree well with not only the McAdams correlation but also the previous studies. The cross-rib turbulators significantly enhance heat/mass transfer in the passage by disturbing the main flow near the surfaces and generating one asymmetric cell of secondary flow skewing along the ribs. Because the secondary flow is induced in the first-pass and turning region, heat/mass transfer discrepancy is observed in the second-pass even for the stationary case. When the passage rotates, heat/mass transfer and flow phenomena change. Especially, the effect of rotation is more dominant than the effect of the ribs at the higher rotation number in the upstream of the second-pass.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.8 s.239
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• pp.911-920
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• 2005

The present study investigates heat/mass transfer and flow characteristics in a ribbed rotating passage with turning region. The duct has an aspect ratio (W/H) of 0.5 and a hydraulic diameter ($D_h$) of 26.67 mm. Rib turbulators are attached in the parallel arrangement on the leading and trailing surfaces of the passage. The ribs have a rectangular cross section of 2 m (e) $\times$ 3 m (w) and an attack angle of $70^{\circ}$. The pitch-to-rib height ratio (p/e) is 7.5, and the rib height-to-hydraulic diameter ratio (e/$D_h$) is 0.075. The rotation number ranges from 0.0 to 0.20 while the Reynolds number is constant at 10,000. To verify the heat/mass transfer augmentation, internal flow structures are calculated for the same conditions using a commercial code FLUENT 6.1. The results show that a pair of vortex cells are generated due to the symmetric geometry of the rib arrangement, and heat/mass transfer is augmented up to $Sh/Sh_0=2.9$ averagely, which is higher than that of the cross-ribbed case presented in the previous study for the stationary case. With the passage rotation, the main flow in the first-pass deflects toward the trailing surface and the heat transfer is enhanced on the trailing surface. In the second-pass, the flow enlarges the vortex cell close to the leading surface, and the small vortex cell on the trailing surface side contracts to disappear as the passage rotates faster. At the highest rotation number ($R_O=0.20$), the turn-induced single vortex cell becomes identical regardless of the rib configuration so that similar local heat/mass transfer distributions are observed in the fuming region for the cross- and parallel-ribbed case.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.6 no.4
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• pp.375-388
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• 1994

When conducting movable bed tests in a narrow wave tank, the hydrodynamics and morphology are assumed to be two-dimensional; hence, any three-dimensional patterns such as cross-tank variations of the profiles are neglected or averaged to represent the mean profiles at the measuring time. In this paper, six movable bed tests were carried out with a fairly fine sand to investigate (1) whether or not three-dimensional features can occur in relatively narrow wave tanks, and (2) various possible interrelationships and causes of the three-dimensionality. These movable bed studies suggested that there was a relatively slow feedback between the hydrodynamics and the morphology that led to initiation and growth of 3-D morphological features, resulting in cross-tank profile variations under certain stages of profile development, especially when the profile approached an equilibrium with overall stability.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.6
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• pp.205-212
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• 2004

In this paper the design of a 1-[KVA] fuel cell powered line-interactive UPS system employing modular (fuel cell & DC/DC converter) blocks is proposed. The proposed system employs the two fuel cell modules along with suitable DC/DC converters and these modules share the DC-Link of the DC/AC inverter. A supercapacitor module is also employed to compensate for the instantaneous power fluctuations and to overcome the slow dynamics of the fuel processor. The energy stored in the supercapacitor can also be utilized to handle the overload conditions for a short time period. Due to the absence of batteries, the system satisfies the demand for an environmentally friendly and dean source of the energy. A complete design example illustrating the amount of hydrogen storage required for 1hr power outage, and sizing of supercacpacitor for transient load demand is presented for a 1-[KVA] UPS.

• Journal of Korea Entertainment Industry Association
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• v.13 no.8
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• pp.117-130
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• 2019

After Marx, the issues regarding human labour have been the alienation towards production means and the distributive justice. Fourth industrial revolution and development of AI(Artificial Intelligence) opened the possibility of a independent production and economy system absolutely excluding against human nature and labour. Using robots and AI will deepen demarcation between living things and one not having life, separating the intelligence from the consciousness. At present, so called pre-stage of post human, seeking interests for life, new social relationship and new community will be increased as well. We can understand that interests for small community, self-sufficiency, dailiness, food and body in this context is increasing too. Representative trend towards this cultural phenomena is called as the 'Kinfolk culture.' Work-life balance, 'Aucalme', 'Hygge', 'So-Hwak-Haeng'(a small but reliable happiness) are the similar culture trends as. Vital capitalism, presented by O-Yong Lee, seeks focusing onto living things principles, e.g. 'topophilia', 'neophilia', and 'biophilia' as the dynamics looking for the history substructure, not class struggle and conflicts. He also argues the 'Vital Capitalism' be regarded as a new methodology to anticipate a social system after post human era. G. Deleuze said "arts is another expression method for existential philosophy. It gives a vitality onto philosophy and gives a role to letting abstract concept into definite image." We can find a lot cases arts' imagination overcomes critical point of scientific prediction power in the future prediction. This paper reviews ideas and issues of 'vital capitalism' in detail and explorers imaginating initial ideas of vital capitalism in the film 'Little Forest.'

• Archives of design research
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• v.16 no.3
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• pp.231-240
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• 2003

As all other cultures do, in the background of color of costume, view of life or spirit are contained in the nature or environment that the people lived in are applied. Marring is the ceremony to be socially recognized that both of sexes are unified, assist ancestor and bear future generation. Meaning and symbolism of color are appeared in beauty and organic composition of Lee dynasty. This paper tried to dear up five colors are dean, beautiful and philosophical colors rather than awkward composition of colors through surveying character of five colors appeared in Korean traditional wedding dress that has been succeeded in present age. This paper compared Korean traditional wedding dress and "Dan-chung" of Korea, Japan and China and surveyed theoretical background of Korean traditional color to find character of color appeared in Korean traditional wedding dress. As a result, Korean traditional color is meaningful symbolic color, its origin starts in yin-yang and the live elements of the Oriental cosmogony and it is related with Taoism of Confucianism and color of "Dan-chung." Five colors of yin-yang means everything under the sun and il is the color achieving beauty of balance due to correlation when it is linked to over one color. Further, it contains nature worship and human dignity, prays happiness and gives the significance of "Buksa", meaning of expelling an evil spirit. Formative beauty praying that all creatures are harmonized while human is happy and escapes from uncertainty is the beauty pursuing mental satisfaction as well as visual satisfaction. In future, the creational and characteristic designs that can appeal to world are required through right understanding and study of the beauty of traditional culture beauty of traditional culture

• Journal of Intelligence and Information Systems
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• v.19 no.1
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• pp.19-33
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• 2013

In this research, a proposed Dynamic Virtual Ontology using Tags (DyVOT) supports dynamic search of resources depending on user's requirements using tags from social web driven resources. It is general that the tags are defined by annotations of a series of described words by social users who usually tags social information resources such as web-page, images, u-tube, videos, etc. Therefore, tags are characterized and mirrored by information resources. Therefore, it is possible for tags as meta-data to match into some resources. Consequently, we can extract semantic relationships between tags owing to the dependency of relationships between tags as representatives of resources. However, to do this, there is limitation because there are allophonic synonym and homonym among tags that are usually marked by a series of words. Thus, research related to folksonomies using tags have been applied to classification of words by semantic-based allophonic synonym. In addition, some research are focusing on clustering and/or classification of resources by semantic-based relationships among tags. In spite of, there also is limitation of these research because these are focusing on semantic-based hyper/hypo relationships or clustering among tags without consideration of conceptual associative relationships between classified or clustered groups. It makes difficulty to effective searching resources depending on user requirements. In this research, the proposed DyVOT uses tags and constructs ontologyfor effective search. We assumed that tags are extracted from user requirements, which are used to construct multi sub-ontology as combinations of tags that are composed of a part of the tags or all. In addition, the proposed DyVOT constructs ontology which is based on hierarchical and associative relationships among tags for effective search of a solution. The ontology is composed of static- and dynamic-ontology. The static-ontology defines semantic-based hierarchical hyper/hypo relationships among tags as in (http://semanticcloud.sandra-siegel.de/) with a tree structure. From the static-ontology, the DyVOT extracts multi sub-ontology using multi sub-tag which are constructed by parts of tags. Finally, sub-ontology are constructed by hierarchy paths which contain the sub-tag. To create dynamic-ontology by the proposed DyVOT, it is necessary to define associative relationships among multi sub-ontology that are extracted from hierarchical relationships of static-ontology. The associative relationship is defined by shared resources between tags which are linked by multi sub-ontology. The association is measured by the degree of shared resources that are allocated into the tags of sub-ontology. If the value of association is larger than threshold value, then associative relationship among tags is newly created. The associative relationships are used to merge and construct new hierarchy the multi sub-ontology. To construct dynamic-ontology, it is essential to defined new class which is linked by two more sub-ontology, which is generated by merged tags which are highly associative by proving using shared resources. Thereby, the class is applied to generate new hierarchy with extracted multi sub-ontology to create a dynamic-ontology. The new class is settle down on the ontology. So, the newly created class needs to be belong to the dynamic-ontology. So, the class used to new hyper/hypo hierarchy relationship between the class and tags which are linked to multi sub-ontology. At last, DyVOT is developed by newly defined associative relationships which are extracted from hierarchical relationships among tags. Resources are matched into the DyVOT which narrows down search boundary and shrinks the search paths. Finally, we can create the DyVOT using the newly defined associative relationships. While static data catalog (Dean and Ghemawat, 2004; 2008) statically searches resources depending on user requirements, the proposed DyVOT dynamically searches resources using multi sub-ontology by parallel processing. In this light, the DyVOT supports improvement of correctness and agility of search and decreasing of search effort by reduction of search path.