• The KIPS Transactions:PartD
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• v.12D no.6 s.102
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• pp.921-930
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• 2005

In this paper, a general purpose molecular simulation system which has been developed by the author, are described. One of the most advantageous features is that the molecular simulation system can handle a coarse-grained model as well as an all-atom mode. Therefore, we can simulate mesoscopic phenomena as well as microscopic phenomena with the help of Langevin dynamics simulation and dissipative particle dynamics simulation techniques. Thus we could study anesthesia, protein folding, biopolymer flow in microchannel with single framework, which spans from microscopic to mesoscopic scales. We expect that we can also simulate many other bio/nano systems of technological importance which are not feasible by means of molecular dynamics simulation technique. Finally, performance data are shown and a bottleneck is identified for future optimization.

• Asian Journal of Atmospheric Environment
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• v.4 no.2
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• pp.80-88
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• 2010

In order to offer a better understanding of air pollution of China as well as East Asia we attempted to characterize the chemical properties of the raw coal materials mined in China and their combusted bottom ashes generated from coal fired power plant. To this end, we measured the chemical characteristics of individual bottom ashes and feed coal fragments collected at a coal fired power generator which was operated with the raw coal dug at a coal mine in China. The chemical properties of these two sample types were determined by a synchrotron radiation X-ray fluorescence (SR-XRF) microprobe method. Through an application of such technique, it was possible to draw the 2D elemental maps in and/or on raw coal fragments and fired bottom ashes. The pulverized fine pieces of feed coal mainly consisted of mineral components such as Fe, Ca, Ti, Ca, and Si, while Fe was detected as overwhelming majority. The elemental mass of combusted bottom ash shows strong enrichment of many elements that exist naturally in coal. There were significant variations in chemical properties of ash-to-ash and fragment-to-fragment. Although we were not able to clearly distinguish As and Pb peaks because of the folding in their X-ray energies, these two elements can be used as tracers of coal fire origin.

• Journal of the Korea Furniture Society
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• v.25 no.1
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• pp.19-27
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• 2014

This paper studied the materials of the furniture which the noble men used in Goryeo, based on the furniture material category of solid wood furniture, lacquerware inlaid with mother-of-pearl and hardware. As for the solid wood furniture, the wood and furniture types are inferred based on the documents. The trees used for the wood furniture were zelkova, korean willow, pine, royal paulownia, maidenhair tree, korean pine, chinese juniper and elm. The furniture types were table, chair, wooden bench, small portable table, writing table, and folding screen. As to the types of lacquerware inlaid with mother-of-pearl, most of them were hams with top, which were made of abalone shells. The features of the lacquerware inlaid with mother-of-pearl were in detail and elaborate like the pattern of the full bloomed chrysanthemum. Writing tables were also made of lacquerware as pieces of furniture. Distinctively, the mother-of-pearl furniture material was popular enough to be used even in a horse saddle. Regarding the metal feldspar used as both a practical use and decoration, there are drop handle, hinge, the front basis, and lock seen in the artifacts, which were made of cast iron, bronze, and brass. Their manufacture techniques were eojamoon, bratticing and sheet metal. Through this study of the furniture materials used in Goryeo, it seems that Goryeo furniture focused on the functions rather than on the decorations, and in turn the forms were simple and basic. The technique of mother-of-pearl, a bit elaborate one, was used in the props furniture like kitchen wares, hams, or writing talbes. Probably, the solid wood is inferred to be used in a low wooden bench, a chair, and a table based on the documents.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.4
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• pp.425-435
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• 2016

This paper describes a spread-spectrum clock generation method by utilizing a ${\Delta}{\Sigma}$ digital PLL (DPLL) which is solely based on binary phase detection and does not require a linear time-to-digital converter (TDC) or other linear digital-to-time converter (DTC) circuitry. A 1-bit high-order ${\Delta}{\Sigma}$ modulator and a hybrid finite-impulse response (FIR) filter are employed to mitigate the phase-folding problem caused by the nonlinearity of the bang-bang phase detector (BBPD). The ${\Delta}{\Sigma}$ DPLL employs a two-point modulation technique to further enhance linearity at the turning point of a triangular modulation profile. We also show that the two-point modulation is useful for the BBPLL to improve the spread-spectrum performance by suppressing the frequency deviation at the input of the BBPD, thus reducing the peak phase deviation. Based on the proposed architecture, a 3.2 GHz spread-spectrum clock generator (SSCG) is implemented in 65 nm CMOS. Experimental results show that the proposed SSCG achieves peak power reductions of 18.5 dB and 11 dB with 10 kHz and 100 kHz resolution bandwidths respectively, consuming 6.34 mW from a 1 V supply.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.5 s.120
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• pp.503-510
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• 2007

This paper proposes the design scheme of internal triple band antenna intended for using in GSM900, DCS1800, and PCS1900 bands. The suggested folding metal plates of the two branches are mounted on a dielectric coated ground plane for size miniaturization and durability. Return losses are overlapped when length of metal branches are controlled. This is important technique for wide band operation. For the suggested antenna geometry its return loss was calculated by HFSS 9 simulator, and was shown to be -10 [dB] less within the required band. Also, gain and radiation pattern of antenna were measured using far field measurement system in an anechoic chamber. The measured peak gain is more than 3.0 [dBi], and the average gain is over -1.0 [dBi] for the triple band, which is regarded as satisfactory for the internal antenna application. Also, the radiation pattern for two frequencies shows a similar shape each other within the required band.

• Korean Institute of Interior Design Journal
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• v.17 no.3
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• pp.86-93
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• 2008

The purpose of this study is to find out how the otherness philosophy reveals itself in the principle of F.O.A construction space creation. The traditional philosophy of totality is self-centered and thoughts are based on the subject. It couldn't escape from the world associated with the self, and has subordinated the other to the main body. But the philosophy of otherness transcends the subject, to the open, creative way of thinking which acknowledges deconstruction, decentralization, and non-hierarchy. This is very similar to contemporary architecture, which pursuits change, and also to the current state of society. In construction by the construction group F.O.A, which is doing notable activity this generation, there is an attempt to transcend the fixed subject which is seen in the otherness discussion, and realize recategorization by overcoming the boundaries of subject and object. First, by the realization of landscape architecture using a topographical folding technique, boundaries of the subject and object are demolished in the relationship of the landscape construction, and recategorization. Second, by breaking up the meaning of the surface which is a visual and physical boundary for both the internal and external, recategorization is being done. Third, by making the boundary between the interior and exterior indistinct, cognitive threshold is dissolved, and the relationship between the subject and object is being recategorization. In conclusion, we can see that the many recategorization phenomenons that are happening in the F.O.A construction show the otherness that escapes from the conventional and stationary relationship, and recognizes each other at the same time, forming new relationships.

• Journal of Fashion Business
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• v.18 no.3
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• pp.73-90
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• 2014

Paper, once known and used only as a medium for printing or handicrafts, is now being used in new fields including artistic clothing, and an environment-friendly material for fashion, while the functionality of its formative characteristics and esthetics have been newly highlighted. On this basis, this study performed a content analysis of paper couture and categorization of types of paper modeling techniques based on 904 paper couture submitted to paper fashion shows, exhibitions and contest exhibits from 2001 to 2013. Analysis results showed that paper textile types were most common at 86.64%, while techniques using laminating, bonding, overlapping or paper as-is represented 62.17%. Expressive techniques in which paper was cut or torn and attached to paper clothing was 11.62%, paper folding was 5.75%, drawing and coloring 4.65%, and finally, paper cutting was 2.65%. Meanwhile, among paper modeling techniques using paper yarn textiles, a paper weaving technique was 6.75%. Moreover, other techniques in which paper modeling techniques or subsidiary clothing was blended were 3.65%, and Dak peeling textiles were 1.33%. Paper paste moulding textiles types represented 1.44%, above all papier $m{\hat{a}}ch{\acute{e}}$ techniques of 0.55% and creasing and holding techniques were 0.88%. Paper is sufficient to express the artists' creativity as well as having qualities as an artistic medium, such as variability through combined use with other materials, variation in form, suitability for reuse of waste paper, and environmental friendliness. Also, various paper modeling techniques can be blended with textiles for a generalized technology that overcomes the limits of paper and textiles.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.134-143
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• 2002

According to the result of the experiment, except that Oebal Hanji making, which does not consider the fiber orientation, has a smaller difference between its strength of width and length direction than of Ssangbal Hanii making, there is not a significant difference between Oebal Hanji making and Ssangbal Hanji making. In addition, even though Oebal Hanji making produced indigenous technique is generally felt sturdy because its absolute strength is enhanced by applying fine materials and overlaying several sheets of paper, its relative strength, which is expressed in an index, is not far beyond that of Ssangbal Hanji making Study on the effect of Dochim revealed that Dochim improves remarkably folding endurance and enhances breaking length and the burst strength. Especially, Dochim increase tensile strength. It was also revealed that, indigenous Oebal Hanji making, the higher the number of sheets of paper overlaid is, the higher the tear strength is the increase relatively higher than those of other types of strength. Consequently, Dochim treatment greatly reinforces the imperfect strength of indigenous Hanji. We consider that if we apply Dochim treatment to Ssangbal Hanji making it may bring about abnormal imbalance of strength. We can benefit from the characteristic strength of Oebal Hanji making only when performing paper making and Dochim considering fiber orientation.

• Steel and Composite Structures
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• v.46 no.3
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• pp.319-334
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• 2023

Localizing damages is an essential task to monitor the health of the structures since they may not be able to operate anymore. Among the damage detection techniques, non-destructive methods are considerably more preferred than destructive methods since damage can be located without affecting the structural integrity. However, these methods have several drawbacks in terms of detecting abilities, time consumption, cost, and hardware or software requirements. Employing artificial intelligence techniques could overcome such issues and could provide a powerful damage detection model if the technique is utilized correctly. In this study, the crack localization in flat and folded plate structures has been conducted by employing a Backpropagated Artificial Neural Network (BPANN). For this purpose, cracks with 18 different dimensions in thin, flat, and folded structures having 15⁰, 30⁰, 45⁰, and 60⁰ folding angle have been modeled and subjected to free vibration analysis by employing the Classical Plate Theory with Finite Element Method. A Four-nodded quadrilateral element having six degrees of freedom has been considered to represent those structures mathematically. The first ten natural frequencies have been obtained regarding healthy and cracked structures. To localize the crack, the ratios of the frequencies of the cracked flat and folded structures to those of healthy ones have been taken into account. Those ratios have been given to BPANN as the input variables, while the crack locations have been considered as the output variables. A total of 500 crack locations have been regarded within the dataset obtained from the results of the free vibration analysis. To build the best intelligent model, a feature search has been conducted for BAPNN regarding activation function, the number of hidden layers, and the number of hidden neurons. Regarding the analysis results, it is concluded that the BPANN is able to localize the cracks with an average accuracy of 95.12%.

• Journal of the Korean Society of Radiology
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• v.81 no.2
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• pp.442-447
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• 2020

Iatrogenic foreign bodies are a challenging complication to both the interventional radiologist and patient, resulting in impaired quality of life and substantial financial cost. The case report describes a successful percutaneous transhepatic removal of an intra-abdominal foreign body. A 72-year-old man underwent surgery for placement of a retrievable covered stent for refractory bile leakage after left hemihepatectomy. Three days after placement, stent folding and migration into a chronic biloma cavity occurred via the bile leakage site. By using a balloon catheter technique, the folded stent could be straightened and repositioned into the bile duct to minimize stent-strut injury during retrieval. The interventional approach could be a valid treatment option for intra-abdominal foreign bodies, as well as intravascular foreign bodies. A thorough understanding of devices and techniques can provide the interventional radiologist with valuable information regarding procedural planning and the management of iatrogenic foreign bodies.