• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.3
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• pp.363-372
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• 2020

Anionic radionuclides pose one of the highest risks to the long-term safety assessments of disposal repositories. Therefore, techniques to immobilize and separate such anionic radionuclides are of crucial importance from the viewpoints of safety and waste volume reduction. The main objective of this study is to design a separator with minimum pressure disturbance, based on the concept of a conventional cyclone separator. We hypothesize that the anionic radionuclides can be immobilized onto a nanomaterial-based substrate and that the particles generated in the process can flow via water. These particles are denser than water; hence, they can be trapped within the cyclone-type separator because of its design. We conducted particle tracking analysis using computational fluid dynamics (CFD) for the conventional cyclone separator and studied the effects due to the morphology of the separator. The proposed sandglass-like design of the separator shows promising results (i.e., only one out of 10,000 particles escaped to the outlet from the separation zone). To validate the design, we manufactured a laboratory-scale prototype separator and tested it for iron particles; the efficiency was ca. 99%. Furthermore, using an additional magnetic effect with the separator, we could effectively separate particles with ~100% efficiency. The proposed sandglass-like separator can thus be used for effective separation and recovery of immobilized anionic radionuclides.

• Nuclear Engineering and Technology
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• v.48 no.2
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• pp.360-367
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• 2016

A windowless spallation target can provide a neutron source and maintain neutron chain reaction for a subcritical reactor, and is a key component of China's nuclear waste transmutation of coupling accelerator and subcritical reactor. The main issue of the windowless target design is to form a stable and controllable free surface that can ensure that energy spectrum distribution is acquired for the neutron physical design when the high energy proton beam beats the lead-bismuth eutectic in the spallation target area. In this study, morphology and flow characteristics of the free surface of the windowless target were analyzed through the volume of fluid model using computational fluid dynamics simulation, and the results show that the outlet cross section size of the target is the key to form a stable and controllable free surface, as well as the outlet with an arc transition. The optimization parameter of the target design, in which the radius of outlet cross section is $60{\pm}1mm$, is verified to form a stable and controllable free surface and to reduce the formation of air bubbles. This work can function as a reference for carrying out engineering design of windowless target and for verification experiments.

• Journal of Korea Foundry Society
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• v.12 no.3
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• pp.220-229
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• 1992

The degree of purification and the macrostructure of high purity aluminium were studied through the alternate stirring method in order to improve the nonuniformity of solute concentration in the unidirectional stirring method. The $2^3$ factorial design was done to examine the effects of experimental factors more qualitatively. In the relatively low stirring speed of 1500 rpm with alternate stirring mode, the uniform solute profile and refined grain structure were obtained due to strong washing effect and turbulent fluid flow. It was induced by the transition of the momentum boundary layer by alternation of the stirrer. It was concluded from this study that the alternate stirring mode was more effective to obtain the uniformity of solute even in the stirring speed of 1500 rpm. But the degree of purification decreased below the critical alternating period. When 2N(99.8wt.%) aluminium was used as the starting material the morphology of solid-liquid showed the cellular shape and the columnar grains were inclined to the direction of rotation. This inclined grain growth resulted from the difference of relative velocities of solid and liquid. The inclined angle was increased as the stirring speed increased and solidification proceeded. In the case of 4N aluminium, there was no inclined grain growth and it was confirmed from the macrostructure and SEM work that the morphology of solid-liquid interface was planar. From the factorial design, it was found that the alternate stirring mode showed poorer purification effect than that of unidirectional stirring mode at low speed(500 rpm). In addition, the factor that had the most significant effect on the degree of purification was the stirring speed.

• Journal of Computational Design and Engineering
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• v.3 no.3
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• pp.191-197
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• 2016

Since 3D measurement technologies have been widely used in manufacturing industries edge detection in a depth image plays an important role in computer vision applications. In this paper, we have proposed an edge detection process in a depth image based on the image based smoothing and morphological operations. In this method we have used the principle of Median filtering, which has a renowned feature for edge preservation properties. The edge detection was done based on Canny Edge detection principle and was improvised with morphological operations, which are represented as combinations of erosion and dilation. Later, we compared our results with some existing methods and exhibited that this method produced better results. However, this method works in multiframe applications with effective framerates. Thus this technique will aid to detect edges robustly from depth images and contribute to promote applications in depth images such as object detection, object segmentation, etc.

• Korean Institute of Interior Design Journal
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• no.15
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• pp.39-48
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• 1998

This study has been peformed to investigate storage space types of old-fashioned traditional dwelling units where older couples maintain their traditional farming lives. In this study it is observed that residents of the traditional farm-houses are exposed to higher level of environmental and emotional pressures. However it is also observed that the older residents are generally manifesting a consistent subculture of the old-timers without noticeable complaints. The usage and morphology of storage spaces are as follows: (1) Storage space in the ceiling are under control of old couple and used for seasonally varied farm products and household equipment. (3) All the households use longterm storage space under wooden floor; the hidden ground is used for keeping miscellaneous tools and fermented foods for years. Overall in this stud it is observed that traditional farm houses are well modified for physically and emotionally frail elderly residents.

• Korean Institute of Interior Design Journal
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• v.13 no.1
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• pp.38-45
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• 2004

One of the prominent phenomena since 1960's is the diversity of concepts. It is to deny the standard of meta structure in judging value as a framework of truth understanding. M. Foucault says that we are living in a synchronous, parallel, and scattered epoch. In the architectural approach and interpretation of Ungers, such a phenomenon appears as multi-dimensional relations. The works of Ungers show the concrete manifestation of such thoughts since 1960's. He has exerted significant influence on German architecture through his book ‘Architecture as Theme’ and architectural works. His architecture has focuses on analogy and abstraction on the foundation of his well defined theory. As the features, it shows dialectic relations, mix of confrontation, interests in geometry and morphology. In this respects, the paper tries to find out the relationship between his architectural thoughts and the paintings of Rene Magritte in terms of the attributes of doubleness in the sense of a paradox. Ungers himself refers that he was directly influenced by Magritte.

• Korean Institute of Interior Design Journal
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• v.14 no.5 s.52
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• pp.262-270
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• 2005

The purpose of this study is to search for the characteristics of the theory of 'placeness' permeated through contemporary museum architecture in Korea, and hereby to prove the possibility of coping with the modernity in Korean architecture. In this study the theory of 'placeness' which is asserted by Christian Norberg Schultz has been adopted in debating contemporary architecture in Korea. Therefor the theory of 'placeness' has been researched to get an angle of vision on the proof of coping with the modernity in Korean architecture. Seven contemporary museum architecture which have been completed since 1990 have been examined in the view of morphology, topology, and typology which are the major factors of 'placeness'. Throughout this case study, the post-modernity in museum architecture in Korea has been proved, which establishes that the 'placeness' is one of the alternatives for contemporary architecture in Korea.

• Korean Institute of Interior Design Journal
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• v.14 no.1
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• pp.11-19
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• 2005

As the world becomes more globalized thanks to the fast development of the Internet, a national identity becomes more important than ever before. Based on this, the study searches for the identity of modern American architecture through exploring the influence of modem American fine arts on the contemporary architecture. It was found that the concepts and the attributes of modern American fine arts obviously transferred into the contemporary architecture. The main concept was elimination of any kind of illusion for maximization of reality, and it was rooted Into American culture, the way of life and thinking. With the concept, the attributes were divided into two extreme poles: materiality and morphology: the former was evolved from Abstract Expressionism and Post-Minimalism and transferred into Los Angeles Avant-Garde architecture; the latter was from Pop Art and transferred into Postmodern architecture and Pop Architecture.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.731-733
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• 1988

This paper describes a design of hardware system for real time automatic diagnosis of ECG arrhythmia based on pipeline processor consisting of the three microcomputer. ECG data is acquisited by 12 bit A/D converter with hardware QRS triggered detector. Four diagnostic parameters - heart rate, morphology, axis, and ST segment - are used for the classification and the diagnosis of arrhythmia. The functions of the main CPU were distributed and processed with three microcomputers. There-fore the effective data process and the real time process using microcomputer can be obtained. The interconnection structure consisting of two common memory units is designed to decrease the delay time caused by data transfer between processors and by which the delay time can be taken 1 % of one clock period.

• Korean Journal of Computational Design and Engineering
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• v.12 no.5
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• pp.354-365
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• 2007

We present novel methods to generate a sequence of shapes that represents the pattern of morphological development or transformation of Bezier curves. The presented methods utilize the intrinsic geometric structures of a Bezier curve that are derived from rib and fan decomposition (RFD). Morphological development based on RFD shows a characteristic pattern of structural growth of a Bezier curve, which is the direct consequence of development path defined by fans. Morphological transformation based RFD utilizes development patterns of source and target curves to mimic the theory of evolutionary developmental biology: although the source and target curves are quite different in shapes, we can easily find similarities in their younger shapes, which makes it easier to set up feature correspondences for blending them. We also show that further controls on base transformation for intensity of feature blending, and extrapolation can compensate the immaturity of blended curves. We demonstrate the experimental results where transformation patterns are smoother and have unique geometric style that cannot be generated using conventional methods based on multi-linear blending.