• Title/Summary/Keyword: Cover

Search Result 7,138, Processing Time 0.033 seconds

A Study on Modeling of Spatial Land-Cover Prediction (공간적 토지피복 예측을 위한 모형에 관한 연구)

  • 김의홍
    • Spatial Information Research
    • /
    • v.2 no.1
    • /
    • pp.47-51
    • /
    • 1994
  • The purpose of the study is to establ ish models of land Cover (use) prediction system for development and management of land resources using remotely sensed data as well as ancillary data in the context of multi-dis¬ciplinary approach in the application to CheJoo Island. The model adopts multi-date processing techniques and is a spatial/temporal land-Cover projection strategy emerged as a synthesis of the probability tra-nsition model and the discrimnant-analys is model. A discriminant modelis applied to all pixels in CheJoo landscape plane to predict the most likely change in land Cover. The probability transition model provides the number of these pixels that will convert to different land Cover in a given future time increment. The syntheric model predicts the future change in land Cover and its volume of pixels in the landscape plane.

  • PDF

Runoff Curve Number Estimation for Cover and Treatment Classification of Satellite Image(I): - CN Estimation - (위성영상 피복분류에 대한 CN값 산정(I): - CN값 산정 -)

  • Bae, Deg-Hyo;Lee, Byong-Ju;Jeong, Il-Won
    • Journal of Korea Water Resources Association
    • /
    • v.36 no.6
    • /
    • pp.985-997
    • /
    • 2003
  • The objective of this study is to propose Runoff Curve Numbers(CNs) for land cover and treatment classification of satellite image. For this purpose, land cover classifications by using satellite image in addition to the exiting SCS's land cover and treatment classifications studies and land cover classifications suggested by Ministry of Environment are selected to provide CNs depending on the classifications. CNs estimation method is statistical approach that is suggested by Hjelmfelt(1991). Result of this study may contribute to use efficiently for the estimation of CNs in using satellite image.

A Study on the Recent Changes of Level of Club Cover in P & I Insurance (P & I 보험의 보상한도에 관한 고찰 - 최근의 변화 및 쟁점을 중심으로 -)

  • Shin, Gun-Hoon
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.22
    • /
    • pp.201-226
    • /
    • 2004
  • P & I Clubs are mutual and non-profit making insurers which offer shipowners cover for the contractual and third-party liabilities. Whereas most shipowners obtain P & I insurance to cover for their legal liabilities, they also obtain hull insurance to cover against damages to the hull of their vessels from commercial hull insurers. P & I insurance was distinguished from hull insurance in respect that it offered non-limited cover to shipowner member, but there was a serious debate between P & I Clubs in respect of the non-limited cover. A compromise by International Group of P & I Clubs eventually emerged under which, with effect from 20 February 1997, a financial cap was placed on the obligation of each shipowner to pay catasrophe calls to his club(20% of each ship's property limitation fund under 1976 Limitation Convention). Nevertheless many shipowners felt that this new cap on their potential catastrophe call had been set still too high, while others resisted any reduction in the figure established by the compromise. In the Meantime, the European Commission issued a Statement of Objections in June 1997, in which it indicated its objections with a compulsory single limit common th all the Group clubs as high as the 1997 compromise. Eventually the board of all the Group clubs decided that the figure of 20% of the Limitation Convention per ship property funds should be dropped down to 2.5% from 20 February 1999.

  • PDF

Self-terminated carbonation model as an useful support for durable concrete structure designing

  • Woyciechowski, Piotr P.;Sokolowska, Joanna J.
    • Structural Engineering and Mechanics
    • /
    • v.63 no.1
    • /
    • pp.55-64
    • /
    • 2017
  • The paper concerns concrete carbonation, the phenomena that occurs in every type of climate, especially in urban-industrial areas. In European Standards, including Eurocode (EC) for concrete structures the demanded durability of construction located in the conditions of the carbonation threat is mainly assured by the selection of suitable thickness of reinforcement cover. According to EC0 and EC2, the thickness of the cover in the particular class of exposure depends on the structural class/category and concrete compressive strength class which is determined by cement content and water-cement ratio (thus the quantitative composition) but it is not differentiated for various cements, nor additives (i.e., qualitative composition), nor technological types of concrete. As a consequence the selected thickness of concrete cover is in fact a far estimation - sometimes too exaggerated (too safe or too risky). The paper presents the elaborated "self-terminated carbonation model" that includes abovementioned factors and enables to indicate the maximal possible depth of carbonation. This is possible because presented model is a hyperbolic function of carbonation depth in time (the other models published in the literature use the parabolic function that theoretically assume the infinite increase of carbonation depth value). The paper discusses the presented model in comparison to other models published in the literature, moreover it contains the algorithm of concrete cover design with use of the model as well as an example of calculation of the cover thickness.

Methane Oxidation in Landfill Cover Soils: A Review

  • Abushammala, Mohammed F.M.;Basri, Noor Ezlin Ahmad;Irwan, Dani;Younes, Mohammad K.
    • Asian Journal of Atmospheric Environment
    • /
    • v.8 no.1
    • /
    • pp.1-14
    • /
    • 2014
  • Migration of methane ($CH_4$) gas from landfills to the surrounding environment negatively affects both humankind and the environment. It is therefore essential to develop management techniques to reduce $CH_4$ emissions from landfills to minimize global warming and to reduce the human risks associated with $CH_4$ gas migration. Oxidation of $CH_4$ in landfill cover soil is the most important strategy for $CH_4$ emissions mitigation. $CH_4$ oxidation occurs naturally in landfill cover soils due to the abundance of methanotrophic bacteria. However, the activities of these bacteria are influenced by several controlling factors. This study attempts to review the important issues associated with the $CH_4$ oxidation process in landfill cover soils. The $CH_4$ oxidation process is highly sensitive to environmental factors and cover soil properties. The comparison of various biotic system techniques indicated that each technique has unique advantages and disadvantages, and the choice of the best technique for a specific application depends on economic constraints, treatment efficiency and landfill operations.

Evaluation on the effect of Coal-ash as Landfill Cover Material of Mono-Layer Cover System through the Field Scale Test (현장 실험을 통한 단층형 매립복토시스템의 복토재로서 석탄회의 효과 검토)

  • Yu, Chan;Yun, Sung-Wook;Kang, Sin-Il;Jin, Hae-Geun
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2010.03a
    • /
    • pp.1018-1031
    • /
    • 2010
  • In order to investigate the applicability and suitability of the industrial by-products to landfill final cover, field pilot-scale lysimeter experiments were carried out. The mixture of loamy soil, bottom ash, and construction waste was placed as a cover material in lysimeter($2m{\times}6m{\times}1.2m$) which were constructed with cement brick, and then, volumetric water contents, pF value, and the quantity of runoff and seepage of treatment boxes filled with the mixture of loamy soil and the industrial by-products were monitored from July, 2007 to February, 2008. Among the cases tested, consequently, the case containing the mixture of bottom ash and loamy soil was most effective in engineering and hydrological properties and water retention ability.

  • PDF

A Study on the Flow Field Characteristics of Air Induction System for Reducing the Signal-to-Noise in the MAFS Output

  • Yoo, Seoung-Chool
    • Journal of ILASS-Korea
    • /
    • v.5 no.1
    • /
    • pp.49-57
    • /
    • 2000
  • This study presents the flow visualization results, velocity and turbulence intensity measurements made within an air filter cover and entry region of a mass air flow sensor (MAFS) which is used in an induction system of 3.8L engine. Flow structure in two air filter cover assemblies were examined. The first was a clear plastic replica of the production cover while the second was a modified clear plastic cover with a geometry configured to reduce fluctuations. High speed flow visualization and laser doppler velocimetry (LDV) systems were used to reveal and analyze the flow field characteristics encountered in the sensor design process under steady flow conditions. A 40-watt copper vapor laser was used as a light source. Its beam is focused down to a sheet of light approximately 1.5mm thick. The light scattered off the particles was recorded by a 16mm high speed rotating prism camera at 5000 frames per second. A comparison of the flow patterns and LDV measurements in the original and modified air filter covers is presented to illustrate the controlling effect of the cover design on the turbulence structure formation near the bypass and on the sensor output signal. In both axial and radial planes of the main passage it was found that the turbulence flow pattern is remarkably influenced by the air filter cover and main passage configuration.

  • PDF

Consumer's Sensory Evaluation and Needs of Interior Fabrics for Seat Cover (시트커버용 인테리어 직물의 감성평가와 소비자 요구도)

  • Kim, Jeong-Hwa;Lee, Sun-Young;Lee, Jung-Soon
    • Korean Journal of Human Ecology
    • /
    • v.18 no.3
    • /
    • pp.749-756
    • /
    • 2009
  • Keeping abreast with the latest consumer's trends, industries are focusing on sensibility aspects of products to meet consumer's needs. The car(?) seat cover fabrics are more closely related to human senses than anything else. This study attempted to investigate which seat cover fabric can give good feeling to consumers and to analyze their characteristics. Twelve kinds of jacquard fabric used for seat cover were selected. The Kawabata Evaluation System was used to measure the mechanical properties of 12 jacquard fabrics, and tactile sensibility(TS), and preference(P) determined by subjective evaluation of 160 participants were also utilized. The stepwise regression analysis was made to select the most significant mechanical properties, and some models for predicting tactile sensibility and preference was developed. The results are briefly summarized as follows: the most important parameter to choose seat cover fabric is a "hygienic property" and the other parameters are 'materials with color fastness', 'compressive property', 'color', 'antibacterial property', 'easy-care property'. The LogSMD, LogB, LC, EM were selected as significant mechanical properties affecting tactile sensibility. Also, the LC, LogB, LogSMD, LogWC, LogMMD were selected as significant mechanical properties affecting preference.

Cover Layer Design and Temperature Analysis in Pseudo NFR System Using SIL Head (SIL 헤드유사 근접장 시스템 개발을 위한 보호막 설계 및 열해석)

  • Kim Kyungho;Kim Sookyung;Lee Sung-Q;Park Kang-Ho;Lee Seung-Yop
    • Transactions of the Society of Information Storage Systems
    • /
    • v.1 no.1
    • /
    • pp.58-66
    • /
    • 2005
  • Pseudo-Near Field Recording (Pseudo-NFR) system is proposed to prevent contamination and oxidation of media surface occurred in conventional NFR systems. To solve these critical problems of the NFR systems, we investigate the optimal thickness of cover layer for Pseudo NFR. This paper presents the theoretical analysis for cover layer thickness based on the measured length of dust particle and numerical simulation for the temperature distribution using Finite Difference Time Domain (FDTD) method and heat conduction equation. To verify the simulation results, we conduct and compare simulation results in case of far field MO recording and near field MO recording. A measured dust particle length in general environment was mostly less than $20{\mu}m$, and the optimal thickness of cover layer is $30{\mu}m$ in this case. Based on the designed optimal cover layer thickness, temperature distribution is simulated to have $800{\~}850^{\circ}C$.

  • PDF

An Experimental Study on the Thermal Performance of a Flat-Ship Heat Pipe with Inner Grooves and Screen Mesh Cover (내부에 그루브와 스크린 메쉬를 갖는 평판 스트립형 히트파이프의 열성능에 대한 실험적 연구)

  • Park Soo Yong;Boo Joon Hong
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.29 no.7 s.238
    • /
    • pp.805-813
    • /
    • 2005
  • The thermal performance of a flat-strip heat pipe with inner grooves and the screen mesh cover was investigated experimentally. The heat pipes were made of 2024 aluminum alloy of which the dimensions were 30 (W) $\times$ 4 (T) $\times$ 150 (L) mm. The cross sectional dimensions of inner groove were 0.4$\times$0.9 mm and the space between grooves was 0.6 mm. To enhance the capillary force, foe screen meshes were attached to cover the grooved inner surface. In the grooved heat pipes without screen mesh cover, the maximum thermal load of 180 W (12 W/$cm^2$) was achieved for operating temperature below $130^{\circ}C$ at horizontal position. The heat pipes with screen mesh cover showed the thermal resistances less than one third of those without screen mesh cover, and showed less fluctuation in the thermal resistance values. Furthermore, the thermal performance of the former exhibited less dependence on the tilt angle and the fill charge ratio.