• The KIPS Transactions:PartC
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• v.12C no.2 s.98
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• pp.281-288
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• 2005

It is generally accepted that self-similar (or fractal) Processes may provide better models for teletraffic in modem computer networks than Poisson processes. f this is not taken into account, it can lead to inaccurate conclusions about performance of computer networks. Thus, an important requirement for conducting simulation studies of telecommunication networks is the ability to generate long synthetic stochastic self-similar sequences. A generator of pseudo-random self similar sequences, based on the SRA (successive random addition) method, is implemented and analysed in this paper. Properties of this generator were experimentally studied in the sense of its statistical accuracy and the time required to produce sequences of a given (long) length. This generator shows acceptable level of accuracy of the output data (in the sense of relative accuracy of the Hurst parameter) and is fast. The theoretical algorithmic complexity is O(n).

• Journal of the Microelectronics and Packaging Society
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• v.25 no.2
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• pp.41-48
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• 2018

The quantitative interfacial adhesion energy measurement method of copper redistribution layer and WPR dielectric interface were investigated using $90^{\circ}$ peel test, 4-point bending test, double cantilever beam (DCB) measurement for FOWLP Applications. Measured interfacial adhesion energy values of all three methods were higher than $5J/m^2$, which is considered as a minimum criterion for reliable Cu/low-k integration with CMP processes without delamination. Measured energy values increase with increasing phase angle, that is, in order of DCB, 4-point bending test, and $90^{\circ}$ peel test due to increasing roughness-related shielding and plastic energy dissipation effects, which match well interfacial fracture mechanics theory. Considering adhesion specimen preparation process, phase angle, measurement accuracy and bonding energy levels, both DCB and 4-point bending test methods are recommended for quantitative adhesion energy measurement of RDL interface depending on the real application situations.

• The Journal of Art Theory & Practice
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• no.9
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• pp.59-91
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• 2010

The Bauhaus educational method gave the strong influences on Modern Japanese art and design education. In the 1920s and 1930s, Japan allied with Germany and Italy politically and tried to receive German system to be modernized. The reception of the Bauhaus and Moholy-Nagy's photographic theory was one of those activities at that time. Japanese intellectual class went to the Bauhaus and studied there; Ishimoto Kikuchi, Nakata Sadanosuke, Mijutani Takehiko, Yamawaki Iwao and Yamawaki Michiko(Yamawaki Iwao's wife). Especially, Yamawaki Iwao studied about the architecture at the Bauhaus, but his interest moved toward the photography and the photomontage based on Moholy-Nagy's theory. He studied at the photography workshop of the Bauhaus presented by Peterhans irregularly. Even though Yamawaki Iwao was an architect, he wanted to be admitted as an expert for the photomontage that he particularly studied at the Bauahus as a Bauhaus member. He had presented many articles about the photomontage at the photography magazines in Japan in order to introduce it to Japan since he returned in 1933. Thus, Yamawaki Iwao is the important person when we look back the Modern Japanese design and art history. In Japan, the art and design systems are managed by the Bauhaus educational system until now, and it has become a kind of cultural legacy in Modern Japan; The university of Tama and The university of Tsukuba are the representative educational systems which are based on the Bauhaus legacy. However, Yamawaki Iwao had been concealed as a photographer in Japanese design and photography history until the retrospective discuss named by 'Bauhaus syashin(Bauhaus Photographies)' at the photography magazine, Deja-vu in 1995 and the retrospective exhibition titled as 'Bauhaus syashin(bauahustofografie)' in 1997. This study rethinks of Yamawaki Iwao's historical position while looking at the term as 'Bauhaus Syashin(Bauhaus Photographies)' used in Japan. It is very important to bear in mind Moholy-Nagy's wide variety of approaches to photography at the Bauhaus, but it is impossible to name it 'Bauhaus style'. 'Bauhaus style' is the international style in architecture, but that was never a Bauhaus style in photography. Eugene J. Prakapas indicated that the vague term of 'Bauhaus Photographies' in his article in 1985 as well. This study considers the historical background for the mistake of the term of 'Bauhaus Syashin(Bauhaus Photographies)' in Modern Japanese history, while looking at Yamawaki Iwao's photomontage faintly entering on the historical stage again to discuss the reception of the photomontage from him. In particular, Some of Yamawaki Iwao's photomontage presented as the wall photography in Japan during the Second World War, that was related to the propaganda of Japanese government. It had not been known well in the modern Japanese art and design history because it was related to a declaration of the Second World War by Japan. However, the historical position of his photomontage is very important for Japanese history when we rethink of the reception of the Bauhaus and Moholy-Nagys' photographic theory to build up the Japanese modern history. In the result, this study wants to discuss that the mistake of the term of 'Bauhaus syashin(Bauhaus Photographies)' in Japan is related to the interpretation for the the historical position for Yamawaki Iwao's photomontage in the reception of Bauhaus and Moholy-Nagy's photography in Japan.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.40-51
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• 1991

A Propeller design method using the newly developed blade section(KH18), which behaves better cavitation characteristics, is presented. Experimental results for two-dimensional foil sections show that the lift-drag curve and the cavitation-free bucket diagram of the new blade section are wider comparing to those of the existion NACA sections. This characteristic of the new section is particularly important for marine propeller applications since angle of attack variation of the propeller blade operating behind a non-uniform ship's wake is relatively large. A lifting surface theory is used for the design of a propeller with the developed section for a 2700 TEU container ship. Since the most suitable chordwise loading shape is not known a priori, chordwise loading shape is chosen as a design parameter. Five propellers with different chordwise loading shapes and different foil sections are designed and tested in the towing tank and cavitation tunnel at KRISO. It is observed by a series of extensive model tsets that the propeller(KP197) having the chordwise loading shape, which has less leading edge loading at the inner radii and more leading edge loading at the outer radii of 0.7 radius, has higher propulsive efficiency and better cavitation characteristics. The KP197 propeller shows 1% higher efficiency, 30% cavitation volume reduction and 9% reduction of fluctuating pressure level comparing to the propeller with an NACA section. More appreciable efficiency gain for the new blade section propeller would be expected by reduction of expanded blade area considering the better cavitation characteristics of the new blade section.

• Journal of the Korea Convergence Society
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• v.9 no.2
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• pp.359-369
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• 2018

This study tried to illustrate the process of the experiences of university student athletes in campus who are engaged in study and sports. it is aimed to interpret and describe the everyday life of athlete students, and establishing a desirable human talent and to set the right necessary direction for the education of athlete students. For this, it selected 10 research participants as student athletes in J University located in Chungcheongnam-do and collected data through an in-depth interview. As for the data analysis, concepts were derived according to the grounded theory analysis method suggested by [10] and the research results composing the coding paradigm to clarify the relations between concepts are as following. First, 120 concepts, 17 subcategories, and 10 upper categories were deducted in the open coding. Second, the contextual factors of the campus life motive were "participation in sports" and "participation in study" and the central phenomena were regarded as "the significance of campus life in which study and sports run parallel. The conditions of arbitration were summarized as 'formation of my relations" and "ability improvement" in sports and study, and the operation/interaction strategy were categorized as "importance of study" and "negative thinking." As for the last result, "reflecting campus life", "my own identity", and "planning future" were categorized, and it is judged that the application of the policy to improve the ability of student athletes that comprehend all study and sports.

• Journal of the Korean Magnetics Society
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• v.10 no.5
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• pp.196-202
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• 2000

Top synthetic spin valves with structure Ta/NiFe/CoFe/Cu/CoFe(P1)/Ru/CoFe(P2)/FeMn/Ta on Si(100) substrate with natural oxide were prepared by dc magnetron sputtering system, and investigated on the magnetoresistance properties and effective exchange bias field. As the thickness of FeMn increased above 150 $\AA$, MR ratio was decreased due to the current shunting effect. As the thickness of free layer decreased below 40$\AA$, MR ratio was reduced rapidly. In case of 40 $\AA$ thick of free layer, spin valve film with a structure Si(100)/Ta(50 $\AA$)/NiFe(27 $\AA$)/CoFe(13 $\AA$)/Cu(26 $\AA$)/CoFe(30 $\AA$)/Ru(7 $\AA$)/CoFe(15 $\AA$)/FeMn(100 $\AA$)/Ta(50 $\AA$) exhibited maximum MR ratio of 7.5 % and an effective exchange bias field of 600 Oe, respectively. Thickness difference dependence in this synthetic spin valve structure on effective exchange field was investigated and interpreted by the analytical method. It should be noted that thickness increase of CoFe(P 1) and decrease of CoFe(P2) in synthetic antiferromagnet leaded to the decrease in effective exchange bias field by experimentally and analytically.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.2
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• pp.75-82
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• 2010

The economical efficiency and easy ship building have enabled to spread FRP ships in the shipbuilding field. As waste FRP ships have been thrown away at a river or within a harbour, this matter has become issues. For the improvement of this matter, the melting technique and system of waste FRP ships was developed. But, Decision making was required for a location plan of the melting system of waste FRP ships. It's recognized that the location decision of this system is difficult due to the dependence on technical, economical, environmental factors. In this paper, we survey the primary factors of location-economic, life-environment, infrastructure and make up a question for the experts. We also calculate the important weight and related weight using Fuzzy AHP, Limiting probability method and discuss on the calculation results on the proposed sites.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.2
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• pp.48-59
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• 1992

In this paper, the effects of a skirt deformation on the responses of an Air Cushion Vehicle in waves are investigated. The air in the bag and in the plenum chamber is assumed to be compressible and to have a uniform instantaneous pressure distribution in each volume. The free surface deformation is determined in the framework of linear potential theory by replacing the cushion pressure with the pressure patch moving uniformly with an oscillating strength. And the bag-finger skirt is assumed to be deformed due to the pressure disturbance while its surface area remained constant. The restoring force and moment due to the deformation of bag-finger skirt from the equilibrium shape is included in the equations of hearse and pitch motions. The numerical results of motion responses due to various ratios of the bag and cushion pressure or bag-to-finger depth ratios are shown.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.72-75
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• 1984

The prime cause of yield reduction of sesame is the lodging-induced damage, so a study of analyzing the products of sesame and frequency of a strong wind with the relation was implemented. The regression significance between the maximum velocity of wind during growing period of sesame and products was the highest in the Mokpo, Hampyung, Haenam, and Kohung district of coast but inland districts of Kwangju was non-significant. Estimated degrees of lodging-induced damage by a strong wind was shown as generally 31-41%, but a exceptional degree was observed as high as 80.5% at Mokpo district.

• Journal of Korea Society of Industrial Information Systems
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• v.24 no.2
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• pp.57-63
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• 2019

In order to facilitate the supply of gradually increasing power demand, it is also necessary to increase the number of power cables for power transmission as well as generation facilities. However, the expansion of electric power cables for supplying power to most urban areas requires a space for installation of additional cables, and the space for installing cables in domestic downtown areas is insufficient at present. The superconducting power cable, which can transmit more power with the same size, has emerged as an alternative to overcome the insufficient cable installation space. However, superconducting power cables, which have the advantage of large power transmission, have some losses in the AC (Alternating Current) system. Therefore, the design and analysis of AC losses are essential to introduce superconducting power cables in AC power transmission systems. In this paper, we analyze the AC loss of various superconducting power cables and consider the actual superconducting power cables and their application to the system. Although there is a theoretical calculation method of AC loss for single superconducting wire, it is not easy to calculate AC loss of superconducting power cable with large number. Therefore, the authors intend to analyze various kinds of superconducting power cable AC loss by using electromagnetic finite element analysis considering E-J (Electric field-Current density) characteristics of superconductivity. The analysis of the AC loss characteristics of the superconducting power cable will be an important factor in the design and development of the superconducting power cable to be applied to the actual system.