• Bulletin of the Korean Mathematical Society
• /
• v.56 no.5
• /
• pp.1159-1186
• /
• 2019

In this paper, we study plane curves of degree 6 with points whose multiplicities of the tangents are 5. We determine all the Weierstrass semigroups of ramification points on double covers of the plane curves when the genera of the covering curves are greater than 29 and the ramification points are on the points with multiplicity 5 of the tangent.

• Proceedings of the Korean Geotechical Society Conference
• /
• 1998.10a
• /
• pp.329-336
• /
• 1998

• Transactions of the Society of Information Storage Systems
• /
• v.2 no.3
• /
• pp.178-183
• /
• 2006

A Blu-ray disc, which has a more than 25GB optical capacity, has been known as a promising next-generation optical disc format. It commonly has a 1.1 mm thick substrate and a 0.1 mm thick cover layer for beam transmitting and the protection of the reflecting surface. The cover layer is generally formed by the spin coating process. However, in conventional spin coating, small bumps are formed along the rim of the disc, which results in the fatal reading error. Numerical simulation of the thin film flow behaviors during spin coating with the commercial solver and optimal spinning conditions was obtained. Thickness distribution of the cover layer according to the variation of substrate's edge shape could be calculated as well. By modifying the shape of the substrate edge shape, the bumps along the disc rim could be minimized, and it was proved that the chamfered edge, around $5{\sim}10$ degree, is the simplest and most effective way to minimize the bumps.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.36 no.3
• /
• pp.135-152
• /
• 2018

The purpose of this study is to propose an optimal fusion method of aerial multi - sensor data to improve the accuracy of land cover classification. Recently, in the fields of environmental impact assessment and land monitoring, high-resolution image data has been acquired for many regions for quantitative land management using aerial multi-sensor, but most of them are used only for the purpose of the project. Hyperspectral sensor data, which is mainly used for land cover classification, has the advantage of high classification accuracy, but it is difficult to classify the accurate land cover state because only the visible and near infrared wavelengths are acquired and of low spatial resolution. Therefore, there is a need for research that can improve the accuracy of land cover classification by fusing hyperspectral sensor data with multispectral sensor and aerial laser sensor data. As a fusion method of aerial multisensor, we proposed a pixel ratio adjustment method, a band accumulation method, and a spectral graph adjustment method. Fusion parameters such as fusion rate, band accumulation, spectral graph expansion ratio were selected according to the fusion method, and the fusion data generation and degree of land cover classification accuracy were calculated by applying incremental changes to the fusion variables. Optimal fusion variables for hyperspectral data, multispectral data and aerial laser data were derived by considering the correlation between land cover classification accuracy and fusion variables.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2010.05a
• /
• pp.5-7
• /
• 2010

Corrosion sensors were devised to develop a system whereby the depth of chloride permeation from concrete surfaces can be monitored in cover concrete of reinforced concrete structures. For making sensor which is similar to rebar author uses Screen printer machines, Ag paste and Fe powder. Appropriate portion of Ag and Fe is over 1:2. The resistance of sensors increased as the degree of corrosion increased. And according to cover depth author suggests sensor system which has a demanded cover depth. It was therefore confirmed that the corrosion sensor can monitor chloride permeation by change of resistance.

• Archives of design research
• /
• v.17 no.1
• /
• pp.329-338
• /
• 2004

This study did derive a characteristic of a cover design through considering a concept, a function and components of a cover design based on a literature study and through analyzing cases of the best-seller cover designs for the literature section from 1999 to 2002. In terms of a reader's preference for a cover design according to an age and sex of a reader, it tried to suggest a condition and a method of a book-cover design through a questionnaire survey and the image evaluation. In a survey of the preference for a cover design, there was the difference of interest degree in a kind of a book, a place to buy a book and a cover design according to an age and sex. In addition, it was shown that a woman prefers the stylish typography, and both a man and a woman prefer the cool color. However, except these two, the reason why there is no difference in preference for visual elements are that a cover design is an integrative image comprising several elements. Accordingly, through the Semantic Differential Method, it carried out the evaluation as to a cover design as an integrative image. As a result of that, an abstract image was shown to be difficult to convey a meaning because of its fall in clarity. Further, a cover design mainly comprising the stylish typography gained the high evaluation in unique and clarity. It is thought to be attributable to the easiness to achieve a goal of seeing and reading in a cover design in which an image and the typography are balanced, rather than the excessive visual. Even though the visual is excellent, there was difference from what having been excellent in conveying a meaning, which is a functional aspect. This study tried to examine, limiting it only to a visual element. It will be hereafter required to proceed with a study on the influence on a reader's preference according to material, bookbinding and a form of book which are elements comprising a cover design.

• Bulletin of the Korean Mathematical Society
• /
• v.50 no.2
• /
• pp.667-674
• /
• 2013

Considering a special double-cover Q of the symmetric group of degree 3, we show that a proper non-regular approximate symmetry occurs from its quasigroup homogeneous space. The weak compatibility of any two elements of Q is completely characterized in any such quasigroup homogeneous space of degree 4.

• Journal of the Korea Concrete Institute
• /
• v.17 no.1 s.85
• /
• pp.157-166
• /
• 2005

This article involves architecting prototype-fuzzy expert system for designing the nominal cover thickness by means of fuzzy inference for quantitatively representing the environment affecting factor to reinforced concrete in chloride-induced corrosion environment. In this work, nominal cover thickness to reinforcement in concrete was determined by the sum of minimum cover thickness and tolerance to that defined from skill level, constructability and the significance of member. Several variables defining the quality of concrete and environment affecting factor (EAF) including relative humidity, temperature, cyclic wet and dry, and the distance from coast were treated as fuzzy variables. To qualify EAF the environment conditions of cycle degree of wet-dry, relative humidity, distance from coast and temperature were used as input variables. To determine the nominal cover thickness a qualified EAF, concrete grade, and water-cement ratio were used. The membership functions of each fuzzy variable were generated from the engineering knowledge and intuition based on some references as well as some international codes of practice.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.24 no.8
• /
• pp.599-604
• /
• 2012

Most air pollution and smog are a result of the burning of fossil fuels. The use of fossil fuels also causes acid rain and global warming. So the need for solar energy utilization is increased. It is essentially important to make efforts to reduce usage of fossil energy resources. In this study, we analyzed the correlation between climatic elements(Cloud cover, Duration of sunshine, Temperature) and the photovoltaic power generation. Cloud cover of the correlation coefficient was 0.87. And duration of sunshine of the correlation coefficient was 0.93. The order of the correlation coefficient was duration of sunshine, cloud cover, temperature. To accurately analyze of the degree of correlation for the photovoltaic power generation, additional research about climatic elements that show a high correlation is needed.

• ALGAE
• /
• v.23 no.2
• /
• pp.141-150
• /
• 2008

Populations of Codium amplivesiculatum were found in association with rhodolith beds. We present population trends of C. amplivesiculatum from surveys conducted in the southwestern Gulf of California based on monthly sampling from June 1999 to August 2000. Surveys were conducted at 2 sites in the San Lorenzo Channel at depths of 8 - 12 m. The parameters measured were percent cover, biomass and structure in relation to size of the thalli. From each thallus the following measurements were taken: length and diameter, proportion of each thallus with reproductive structures and the degree of fragmentation (measured as number of small thalli). Mean biomass and cover varied seasonally with the maximum (1036.6 gm$^{-2}$ and 100% cover) present in June 2000 and the minimum in winter (0 gm$^{-2}$ and 0% cover). The longest fronds (3 m) occurred during July 1999 and August 2000, while the maximum diameters of 1.0 cm were present during October and November 1999. There were no significant linear relationships between length and diameter of the fronds, suggesting independent growth. Reproductive structures were common in June and July 1999 with monoic and dioic thalli present. Most fronds were monoic, and this is the first record of this feature for this species. Fragmentation occurred in September, and may be associated with stress from early gametangial reproduction and the combination of high temperatures and low nutrients. A hypothetical life cycle for the species is presented.