• Title/Summary/Keyword: $<_+$-stable

Search Result 22,032, Processing Time 0.05 seconds

Physical Disturbance Improvement Evaluation and Habitat Suitability Analysis by Stable Channel Design (안정하도 설계에 따른 물리적 교란개선 평가와 서식적합도 분석)

  • Lee, Woong Hee;Choi, Heung Sik
    • Ecology and Resilient Infrastructure
    • /
    • v.3 no.4
    • /
    • pp.285-293
    • /
    • 2016
  • This study conducted the evaluations of stable channel and physical disturbance improvement for optimal construction of river structures by focusing on Wonju River. A stable slope was analyzed sectionally for stable channel design, and in order to satisfy the stable slope, river structure improvement scenarios were deduced. Accordingly, through physical disturbance improvement evaluation for each scenario, the study extracted the optimal scenario for stable channel design and physical disturbance improvements. The changes in physical habitat were analyzed when river structure improvements were made for stable channel design and physical disturbance improvement. Zacco koreanus, an indicator fish of the soundness of the aquatic ecosystem, was selected as a restoration target species by investigating the community characteristics of fish fauna and river environments in the Wonju River. The habitat suitability was investigated by the PHABSIM model with the habitat suitability index of Zacco koreanus. The results of the prediction evaluation showed a slight decrease in habitat suitability and weighted usable area. However, it was not influenced by the improvements in the river structure. The study suggested river structure arrangement methods that can improve physical soundness and safety of Wonju River, and confirmed that there were no effects to the changes in the physical habitat.

Unveiling dietary lifestyle of a Joseon-era mummy by extracting isotopic information from hair and bone (조선시대 회곽묘 출토 미이라의 안정동위원소 분석으로 생애 주기에 따른 식생활 변화 추적)

  • Kang, Da Young;Shin, Ji Young
    • Analytical Science and Technology
    • /
    • v.25 no.5
    • /
    • pp.300-306
    • /
    • 2012
  • This study reports the stable carbon and nitrogen isotope of mummy, the preserved human time capsule from Joseon Dynasty. The stable isotopic composition of biological tissue is expected to be a direct and constant function of diet because the stable isotope ratios do not decay or change in abundance through time. Over the past three decades, stable carbon and nitrogen isotope analysis has been extensively applied for archaeological topics. However, this is the first case in Korean mummy to extract palaeodietary information using stable isotope analysis. We extracted isotopic information from bone collagen and hair keratin, which reflects the lifetime average diet and short-term diet, respectively. The average values of ${\delta}^{13}C$ and ${\delta}^{15}N$ values are -19.0‰ and 11.4‰ (bone collagen), and -21.3‰ and 14.3‰ (hair keratin). Stable carbon isotope shows a mainly $C_3$-based diet from cradle to grave. On the other hand, there is significant difference in stable nitrogen isotope which implies a relatively enriched diet before death. We expect this study opens up a potential to understand the palaeodietary lifestyle in Joseon Dynasty.

Stable Channel Design for the Gravel-bed River Considering Design Constraints (설계구속인자를 고려한 자갈하상 하천의 안정하도 설계)

  • Ji, Un;Jang, Eun-Kyung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.16 no.4
    • /
    • pp.2860-2867
    • /
    • 2015
  • Stable channel design is to determine the width, depth and slope for satisfying the condition that the upstream incoming sediment rate is equal to the sediment transport rate at the design channel. Therefore, the most sensitive variable when designing a stable channel is the selection of a sediment transport equation applied for the channel design. Especially if in the case of gravel beds the designer uses the equation developed by using the data of sand rivers, the calculation result of the stable channel section has large errors. In this study, the stable channel design has been applied to the gravel bed river using the previous stable channel design program with newly added the sediment transport equation for gravel beds; and the stable channel section considering design constraints has been produced by using the analytical method. As results, in the case of the application with the fixed width, the depth predicted by Ackers and White's equation was the shallowest and Meyer-Peter and $M\ddot{u}ller's$ equation was 0.8 m deeper than the current section of 2.4 m. In the case of the application with the fixed depth, the width predicted by Engelund and Hansen's equation was twice wider than the current section and by Meyer-Peter and $M\ddot{u}ller's$ equation was 20 m wider than the current section of 44 m.

Relationship Between Soil Water-Stable Aggregates and Physico-chemical Soil Properties (토양 내수성 입단과 토양특성과의 관계)

  • Hyun, Byung-Keun;Jung, Sug-Jae;Song, Kwan-Cheol;Sonn, Yeon-Kyo;Jung, Won-Kyo
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.40 no.1
    • /
    • pp.57-63
    • /
    • 2007
  • Soil aggregation has been considered as an important factor not only for increasing soil productivity and soil quality but also improving nutrient use availability and water use efficiency. However, the relationship between soil aggregation and soil properties hasn't well reported for Korean soils. Objective of this research was to identify the relationship among soil water-stable aggregate (WSA), soil properties and soil dispersion ratio. Soil samples were analyzed for water-stable aggregate, Middleton's dispersion ratio, and soil physical and chemical properties. Water-stable aggregate was significantly correlated to soil textural properties, soil organic matter, and exchangeable cations. Middleton's dispersion ratio was significantly correlated with water-stable aggregate ($r=-0.76^{***}$). Regression equation for water-stable aggregate was estimated by Middleton's dispersion ratio (Y=-0.79X + 96.49; $r^2=0.58^{**}$). In this research, we conclude that water-stable aggregate was significantly correlated with some soil properties and was able to be estimated by rapid and easily measurable Middleton's dispersion ratio.

STABILITY FOR INTEGRO-DELAY-DIFFERENTIAL EQUATIONS

  • Goo, Yoon-Hoe;Ryu, Hyun Sook
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.13 no.1
    • /
    • pp.45-51
    • /
    • 2000
  • We will investigate some properties of integro-delay-differential equations, $$x^{\prime}(t)=A(t)x(t-g_1(t,x_t))+{\int}_{t_0}^{t}B(t,s)x(s-g_2(s,x_s))ds,\;t_0{\geq}0,\\x(t_0)={\phi}$$,

  • PDF

A NOTE ON Z-IDEALS IN BCI-SEMIGROUPS

  • Ahn, Sun-Shin;Kim, Hee-Sik
    • Communications of the Korean Mathematical Society
    • /
    • v.11 no.4
    • /
    • pp.895-902
    • /
    • 1996
  • In this paper, we describe the ideal generated by non-empty stable set in a BCI-group as a simple form, and obtain an equivalent condition of prime Z-ideal.

  • PDF

An Unusually Stable S-Nitrosothiol from Glutathione

  • Park, Jeen-Woo;Means, Gary-E.
    • Archives of Pharmacal Research
    • /
    • v.12 no.4
    • /
    • pp.257-258
    • /
    • 1989
  • Glutathione was converted by $HNO_2$ into a S-nitrosothiol which was stable in solution and atypically so even as a solid. FAB/MS and IR data have been obtained for the confirmation of structure of S-nitrosogulathione in the crystalline state.

  • PDF

Driver electronics for commercialization of emerging display technologies

  • Wai-Yan, Stephen
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2006.08a
    • /
    • pp.298-302
    • /
    • 2006
  • Driver electronics for emerging display technologies are presented for OLED's, microdisplays, electrophoretic displays & bi-stable LCD's. Key factors for commercialization of these technologies are derived from the experience of the LCD's, including driver IC designs, wafer and assembly processes & applications.

  • PDF