• 제목/요약/키워드: history of natural number

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Ab-Anbar, the Ancient Underground Water Houses of Iran

  • Yazdi, J. Tababaee;Han, Moo-Young
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.1438-1441
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    • 2008
  • Throughout the history, the people of Iran have battled the dryness by innovations to preserve every drop of water that lands from the rare clouds, or from a stream flowing out of distant springs. Water is precious and held with highest respect, whether stored for drinking at an Ab-Anbar, or for washing and farming at the Houz in the middle of their oasis homes and orchards, or sourced at a Qanat spring or Jooy under ground. How it is that drinking water as cold as a mountain fall is found in desert of Iran? Ab-Anbar is an ancient means of water preservation and cooling through anunderground building structure. These underground structures have been present in Khorasan and other desert provinces of Iran as public or private water storage facilities, widely used before the installation of public plumbing systems in the late 1950s. Although many of these structures are still functional, most have been protected by government for restoration or viewing by the public as historical heritage. Khorasan natural dry climate and the massive surrounding deserts have been a breeding ground for many designs of Ab-Anbars. Today the existing number of such facilities stands in the province of Khorasan. Usually these structures were built in populated areas, also there are some forms of such structures on old trade routes and roadways leading to and from populated towns. This paper considers the history of Ab-Anbars in Khorasan as well as other relevant aspects such as types, components, construction methods and materials, filling and withdrawal systems.

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The Life - History of Radix auricularia coreana under Different Laboratory Condition (사육조건에 따른 물달팽이 ( Radix auricularia coreana ) 의 실험실 생태조사)

  • 조신형;이정길
    • The Korean Journal of Malacology
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    • v.12 no.1
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    • pp.47-51
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    • 1996
  • Radix auricularia coreana, the intermediate host of Fasciola gigantica, is the most common pulmonate snail in Korea, This species is often found intermingled with Austropeplea ollula, the intermediate host of F. hepatica, in their natural habitats. In the present study. the life history of Radix auricularia coreana was examined under three different laboratory conditions. Egg-masses were taken from the field-collected adult R. auricularia coreana and incubated in the temperature ramges of 22-26$^{\circ}C$. The hatching began after 11 days from spawned eggs, and complete hatching took about 12 days. The hatching rate was about 88%. The juvenile snails were cultured at three different laboratory conditions. When the juvenile snails were cultured in the aquarium fed on lettuce leaves at 22-26$^{\circ}C$, the snails reached 20 mm in shell length at 86 days after hatching. The bottom of each aquarium was filled up with washed sand(1.5 cm) and decomposing ark shells were put on the sand. The aquarium was then filled with four litres of distilled water and continuously aerated. Most of snails (93%) survived until the experimenta period. The dggs are laid in 40 days after hatching; the averge number of eggs per egg-mass was 40.8.

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Effects of Host plant, Nectar plant and Vegetation types on Butterfly Communities (먹이식물·흡밀식물·식생이 나비 군집에 미치는 영향)

  • Kim, Do Sung;Cho, Young Bok;Jeong, Jong Chul
    • Korean journal of applied entomology
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    • v.51 no.4
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    • pp.331-342
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    • 2012
  • The effects of number of host plants and nectar plants on the number and diversity of butterflies were monitored and analyzed by simple and multiple regression from May 2008 to Sep 2009 in the Bubjusa region (Mt. Sokri, Boeun-gun, Chungcheongbuk-do), which was divided into four regions. The results demonstrate that the number of butterflies has a positive correlation with the number of host plant species, the number of nectar plant species, and the number of host plants multiple regression analysis. The number of butterflies also increased habitat area. However, the butterfly species number and diversity index showed lower correlation with the number of host plants and the area size of the divided region, respectively, when analyzed by simple regression. In addition, increased species diversity in a region with more diverse plant flora. These results suggest that the composite distribution of host and nectar plants with diverse plant flora is required for butterfly diversity and population preservation. Additionally, it also suggest that vegetation types complementarity all factors.

Fatty acid analysis as a tool to infer the diet in Illinois river otters (Lontra canadensis)

  • Satterthwaite-Phillips, Damian;Novakofski, Jan;Mateus-Pinilla, Nohra
    • Journal of Animal Science and Technology
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    • v.56 no.5
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    • pp.16.1-16.9
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    • 2014
  • Fatty acids (FA) have recently been used in several studies to infer the diet in a number of species. While these studies have been largely successful, most have dealt with predators that have a fairly specialized diet. In this paper, we used FA analysis as a tool to infer the diet of the nearctic river otter (Lontra canadensis). The river otter is an opportunistic predator known to subsist on a wide variety of prey including, fishes, crayfish, molluscs, reptiles and amphibians, among others. We analyzed the principle components of 60 FA from otters and 25 potential prey species in Illinois, USA. Prey species came from 4 major taxonomic divisions: fishes, crayfish, molluscs and amphibians. Within each division, most, but not all, species had significantly different profiles. Using quantitative FA signature analysis, our results suggest that, by mass, fish species are the most significant component of Illinois River otters' diet ($37.7{\pm}1.0%$). Molluscs ranked second ($32.0{\pm}0.8%$), followed by amphibians ($27.3{\pm}4.3%$), and finally, crayfish ($3.0{\pm}0.6%$). Our analysis indicates that molluscs make up a larger portion of the otter diet than previously reported. Throughout much of the Midwest there have been numerous otter reintroduction efforts, many of which appear to be successful. In regions where mollusc species are endangered, these data are essential for management agencies to better understand the potential impact of otters on these species. Our analysis further suggests that quantitative FA signature analysis can be used to infer diet even when prey species are diverse, to the extent that their FA profiles differ. Better understanding of the otter's metabolism of FA would improve inferences of diet from FA analysis.

Effect of 17β-estradiol on Life History Parameters and Morphological Deformities in Tigriopus japonicus sensu lato: A Two-generation Studies (17β-estradiol에 노출된 저서성 요각류 Tigriopus japonicus s.l.의 세대간 생활사 및 형태학적 변이 연구)

  • Bang, Hyun-Woo;Lim, Dong-Hyun;Lee, Won-Choel
    • Ocean and Polar Research
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    • v.32 no.4
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    • pp.369-377
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    • 2010
  • To characterize ecotoxicological responses to a natural estrogen, $17{\beta}$-estradiol, we evaluated the life-history of the parental ($F_0$) and first generation ($F_1$) of the harpacticoid copepod, Tigriopus japonicus sensu lato. We evaluated the survival of nauplii and copepodites, the number of days until the emergence of copepodites and adult males, the sex ratio, brooding success, and the first brooding day of adult females. No significant differences in the survival rate were noted in response to treatments with different concentrations of $17{\beta}$-estradiol. However, $17{\beta}$-estradiol induced developmental delay and skewed the sex ratio toward males. Copepod development was delayed significantly in the 0.1 and $1\;{\mu}g\;l^{-1}$ $17{\beta}$-estradiol treatment groups relative to the control group, with a more pronounced delay in the $F_1$ group. Body length and biomass were significantly smaller in the $17{\beta}$-estradiol treated groups than in the controls. The male emergence of T. japonicus s.l. was very high in the 10 and $30\;{\mu}g\;l^{-1}$ $17{\beta}$-estradiol treatment group. Furthermore, exposure to $17{\beta}$-estradiol resulted in morphological deformities such as shrinking and swelling of the urosome, twisted setae of the caudal rami, setal loss of swimming legs, abnormal segmentation of antennules, and dwarfism.

A Faunistic Study of Moths (Insecta, Lepidoptera) on Is. Aphae-do, Sinan-gun, Jeollanam-do, Korea (전남 신안군 압해도의 나방상)

  • Lim, Jin-Taek;Kim, Seok-Yee;Kim, Byoung-Woon;Choi, Sei-Woong
    • Korean Journal of Environmental Biology
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    • v.25 no.2
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    • pp.178-189
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    • 2007
  • We surveyed the moth fauna on Is. Aphae-do, Sinan-gun, Jeollanam-do from March to September 2006 to investigate moth diversity and basic faunal data for ecosystem change on the Island. Three hundred thirty-nine moth species, which comprised 16 families and 241 genera, were recognized. The most dominant species was a pyralid moth, Endotricha olivacealis (116 indivs.). Common species included Chiasmia hebesata, Agnidra scabiosa, and Sophta ruficeps. Two hundred-one species (59.2%) were collected only once during investigation period. The family Noctuidae with 129 species was dominant in the area followed by Geometridae (81 species) and Pyralidae (38 species). Based on number of collected individuals, Geometridae was highest and followed by Noctuidae, Pyralidae and Sphingidae.

The Effects of the Breeding site of the Egrets and Herons by Road Construction, Palhyun-ri, Daegu, Korea (대구광역시 팔현리 지역 도로공사가 백로류 번식지에 미치는 영향)

  • Cha, Jae-Seok;Kim, Jae-Woong;Park, Hee-Cheon
    • Korean Journal of Environment and Ecology
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    • v.22 no.2
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    • pp.152-158
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    • 2008
  • This survey was conducted to analyze the effect of road construction near the group breeding places of the egrets and herons located at Palhyun-ri, Daegu, on their breeding during four years from 2003 to 2006. With the number of the individuals of the whole egrets and herons have been decreased due to the three-year road construction work(2003-2005). When the road construction was temporally stopped in 2006, the number of individuals of egrets and herons except Cattle egret Bubulcus ibis increased and partocilarly, the Gray heron Ardea cinerea was found to have been influenced the most by this construction in comparison with other egrets and herons. The number od individuals of large egrets, little egrets and herons was found to decrease during the construction period. After cutting off the nest trees and removing some parts of the breeding site, the herons and egrets tended to move their nesting place from roadsides to the inside of the breeding area. Trees for the nests decreased due to the increase in fellen trees caused by bird nests per tree increased gradually. As for the formation ratio of trees for the nests, the ratio of pine trees lowered yearly while that of acacia and oak trees was increasing during the survey.

Avifauna and Management of Breeding Season in Taeanhaean National Park (태안해안국립공원의 번식기 조류상과 관리)

  • Paik, In-Hwan;Jin, Seon-Deok;Yu, Jae-Pyoung;Paek, Woon-Kee
    • Korean Journal of Environment and Ecology
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    • v.24 no.2
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    • pp.139-146
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    • 2010
  • The survey was done in order to find what kinds of birds visit Taeanhaean National Park during breeding season, where we fixed up 10 coastal areas and islands within the National Park. Three groups concurrently performed the field research from 5th to 9th of July in 2009. Total 58 species and 7,323 individuals were recorded in Taeanhaean National Park. 48 species including 6,187 individuals were observed in coastal areas and 33 species including 1,136 individuals in island areas. The most dominant species in the National Park are Larus crassirostris which accounts for 60% of the birds inhabiting there, and they seem to have been bred in the islands near the National Park. The birds observed only around the coastal areas include Anas poecilorhyncha, Fulica atra, Egretta intermedia and the others which consist of 25 species and amount to 318 individuals, and the birds found exclusively in island areas include Phalacrocorax filamentosus, Apus pacificus¸ Locustella pleskei and other birds, which consist of 10 species and the number of those individuals observed was 308. The inhabited islands areas such as Gauido were characterized by high ratio of waterbird population, which seems to be correlated with the factors such as the extent of island, the richness of water resources, and the diversity of habitats. Based on the data collected during the research and other data from the previous observations, the kinds of dominant species remain nearly unchanged. And in spite of the oil spill accident in 2007, the increase in the number of waterbirds compared to 2004 may be the evidence that the area is recovering from the environmental pollution. At present, the tidal power plants are being built or scheduled to be built and large-scale reclamation is also under way. What is worse, those areas are seeing the increase of pension construction, which is likely to be the potential cause of damage and disturbance against some key habitats for the waterbirds. Therefore, it is a major priority that we build the bird information system to efficiently manage the knowledge-based asset collected from bird-watching groups and to better monitor the areas that need enhanced database through which the National Park can be appropriately administered.

Spectral element method in the analysis of vibrations of overhead transmission line in damping environment

  • Dutkiewicz, Maciej;Machado, Marcela
    • Structural Engineering and Mechanics
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    • v.71 no.3
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    • pp.291-303
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    • 2019
  • In the paper the analysis of natural vibrations of the transmission line with use of spectral elements and the laboratory experiments is performed. The purpose of the investigation is to analyze the natural vibrations of the transmission line and compare with the results obtained in the numerical simulations. Particular attention is paid to the hysteretic and aerodynamic damping analysis. Sensitivity of the wave number is performed for changing of the tension force, as well as for the different damping parameters. The numerical model is made using the Spectral Element Method. In the spectral model, for various parameters of stiffness, damping and tension force, the system response is checked and compared with the results of the accelerations obtained in the measurements. A frequency response functions (FRF) are calculated. The credibility of the model is assessed through a validation process carried out by comparing graphical plots of FRF and time history analysis and numerical values expressing differences in acceleration amplitude (MSG), phase angle differences (PSG) and differences in acceleration and phase angle total (CSG) values. The next aspect constituting the purpose of this paper is to present the wide possibilities of modelling and simulation of slender conductors using the Spectral Element Method. The obtained results show good accuracy in the range of both experimental measurements as well as simulation analysis. The paper emphasizes the ease with which the sensitivity of the conductor and its response to changes in density of spectral mesh division, tensile strength or material damping can be studied.

A Study on typhoon damage prevention measures about the facility of the rural areas - Focused on Jeollabuk-do area - (농촌지역 시설물의 태풍피해 예방 및 대책에 관한 연구 - 전북지역을 중심으로 -)

  • Lee, Deog-Yong;Kim, Il-Jung
    • Journal of the Korean Institute of Rural Architecture
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    • v.14 no.4
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    • pp.117-124
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    • 2012
  • The purpose of this study is the impact of the typhoon damage to housing and facilities in rural areas. House of damage, as well as the only including damage of facilities in rural areas, particularly greenhouse(Glass greenhouse, Plastic greenhouse, Vinyl greenhouse) leads to damage of crops the scale of the damage increases. In this study, focused on Jeollabuk-do area, accompanying him, the number of gale damage and evaluate the extent of the damage to the typhoon. And aims to provide basic data for the rural areas of strong winds and typhoons preparedness and facility design based on the results. Judging from the results of the analysis of natural disasters caused by typhoons and strong winds, the city formed mainly in the area than in the plains or coastal rural areas compared to other areas more damage can appear. In recent years, many design maximum wind speed of 40m/s wind over because disaster type, even if the standard installation, preferably determined through a precise structural analysis to ensure the structural history of acting urgently.