• Ocean Systems Engineering
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• v.4 no.4
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• pp.293-308
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• 2014

Unlike the traditional displacement type vessels, the high speed planing crafts are supported by the lift forces which are highly non-linear. This non-linear phenomenon causes their motions in an irregular seaway to be non-Gaussian. In general, it may not be possible to express the probability distribution of such processes by an analytical formula. Also the process might not be stationary or ergodic in which case the statistical behavior of the motion to be constantly changing with time. Therefore the extreme values of such a process can no longer be calculated using the analytical formulae applicable to Gaussian processes. Since closed form analytical solutions do not exist, recourse is taken to fitting a distribution to the data and estimating the statistical properties of the process from this fitted probability distribution. The peaks over threshold analysis and fitting of the Generalized Pareto Distribution are explored in this paper as an alternative to Weibull, Generalized Gamma and Rayleigh distributions in predicting the short term extreme value of a random process.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1998.10b
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• pp.27-36
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• 1998

This paper presents a brief outline of dynamic stability of damaged ship in rough, beam wind and waves. The one degree-of-freedom, linear roll equation is adopted with the effects of damage fluid and external forces, but without the effect of sloshing. We evaluate the dynamic stability in terms of capizing probability based on energy balance mechanics and risk analysis , the method of which was proposed by Umeda [2] to the high speed crafts. As a result, we can predict the dynamic stability quantitatively according to sea state , operating and damage conditions.

• Journal of Korean Society of Rural Planning
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• v.18 no.4
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• pp.141-152
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• 2012

Recently the package design for agricultural product of farm stay is great interests for increasing the income of farmers and villages as it may fulfill the sensible needs of consumers who experience rural culture and farm stay. This paper presents the status of the package design for agricultural product of farm stay and proposed improvements to the package design as following; 1)to diversify the packaging capacity, 2)to develop the cultural products to applicate the traditional crafts technique, 3)to provide institutional strategies for presenting the identity of farm or village, 4)to develop the education program about package design. We sampled fifty pilot farms or villages, analyse the package design of them and questionnaire surveyed farmers and managers in order to find problems and suggest improvements.

• Applied Biological Chemistry
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• v.35 no.6
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• pp.470-474
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• 1992

For the further development of thelepin analog as antibiotic agents, we undertook the synthesis of spirobenzopyranone derivative ${\underline{5}}$ as thelepin analog by oxidative phenol coupling. The spirobenzopyranone analog ${\underline{5}}$ showed high activity against Bacillus subtilis (IFO 3108) in $5\;{\mu}g/disc$.

• Advances in nano research
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• v.9 no.2
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• pp.69-82
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• 2020

In this paper, a new explicit analytical formula is derived for the critical buckling load of Double Walled Carbon Nanotubes (DWCNTs) embedded in Winkler elastic medium without taking into account the effects of the nonlocal parameter, which indicates the effects of the surrounding elastic matrix combined with the intertube Van der Waals (VdW) forces. Furthermore, we present a model which predicts that the critical axial buckling load embedded in Winkler, Pasternak or Kerr elastic medium under axial compression using the nonlocal Donnell shell theory, this model takes into account the effects of internal small length scale and the VdW interactions between the inner and outer nanotubes. The present model predicts that the critical axial buckling load of embedded DWCNTs is greater than that without medium under identical conditions and parameters. We can conclude that the embedded DWCNTs are less susceptible to axial buckling than those without medium.

• Computers and Concrete
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• v.26 no.1
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• pp.53-62
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• 2020

Concrete is the most widely used substance in construction industry, so it's been required to improve its quality using new technologies. Nowadays, nanotechnology offers new frontiers for improving construction materials. In this paper, we study the stability analysis of the Single Walled Carbon Nanotubes (SWCNT) reinforced concrete cylindrical shell embedded in elastic foundation using the Donnell cylindrical shell theory. In this regard, we propose a new explicit analytical formula of the critical buckling load which takes into account the distribution of SWCNT reinforcement through the thickness of the concrete shell using the U, X, O and V forms and the elastic foundation using Winkler and Pasternak models. The rule of mixture is used to calculate the effective properties of the reinforced concrete cylindrical shell. The influence of diverse parameters on the stability behavior of the reinforced concrete shell is also discussed.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.5
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• pp.534-541
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• 2007

This paper suggests the mathematical method for the estimation of the required engine output for WIG crafts. The engine size of a WIG craft Is a key parameter in the design stage, because WIGs should overcome the hump drag during the take-off. Therefore, it is very important for a WIG designer to estimate required power and state change during take-off. The mathematical method was developed based on the steady planing state model of a planing boat. Through numerical calculations on various take-off states, it was found that the suggested method could give reasonable estimation of required power and state change during take-off.

• Journal of the Korea Furniture Society
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• v.23 no.4
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• pp.425-434
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• 2012

The concept of humanity is considered as the common issue of various areas in the $21^{st}$ century. The diverse issues such as social design, social enterprise, and ethical consumption, etc., actually involves in the humanity. The unique aspect is that they focus on the disadvantaged group and want to do something for their severe situation in spite of the economic recession all the world faced. This paper shows how the social design appeared as a paradigm of the $21^{st}$ century design on the historical consideration, and tries to prove that the social design is not a new trend but the subtle movement that begun from $19^{th}$ century.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.441-443
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• 2003

The Bamboo stands, which had been planted for agricultural uses, have been spreading from fields to hills and mountains beyond farmers’ expectation over the last 50 years. Bamboo stands yield bamboo shoots to be served as a vegetable dish (‘takenoko in Japanese’) every spring, and supply materials for bamboo crafts in various ways. Now, as bamboo products have lost their social demand, bamboo stands has been gradually abandoned. This has resulted in the wild and unfavorable spread of bamboo stands in many regions over the western half of Japan. This paper illustrates the unfavorable spread of bamboo stands regionally in the southern Kyoto from 1985 to 1999 and the Yamashiro area from 1948 to 2000 through the observation of satellite images and aerial photographs.

• Korean Journal of Heritage: History & Science
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• v.33
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• pp.136-161
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• 2000

This paper is a study on the design of the gilt-bronze sarira caskets discovered in 1959 and 1996, from a east and a west three-story stone pagodas in Gameunsa Temple site which was built in 682. One of the most interesting discoveries is the ceiling with Bokdu(覆斗) design which can be seen in Dun-Huang grotto of China, reflected upon the ceiling structure of the cover (outer casket) and the square box (inner casket). The structure of these sarira caskets, as art crafts, directly represents architectural structure of Dun-Huang grotto that was made during the early T'ang period of China. Moreover, the sarira caskets are decorated with ornate designs and these designs also can be seen on the murals of Dun-Huang grotto. Accordingly, those sarira caskets tell us creative ability and international taste of Silla's craftsmen. By tracing the origin of structure and design pattern of the sarira caskets to Central Asian and Chinese architectures, it is able to understand international style of the sarira caskets of Gameunsa Temple site.