• Title/Summary/Keyword: size diversity

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Response of a Miscanthus sinensis Grassland in an Early Successional Old-Field to Fertilization

  • Song, Jong-Suk
    • Journal of Plant Biology
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    • v.37 no.1
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    • pp.1-8
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    • 1994
  • The effects of fetilization on the structure and function of an early successional Miscanthus sinensis grassland were investigated in an old-field ecosystem at Honjo city, Saitama Prefecture, Japan from 1981 to 1982. Compared to control plot, life form composition of treatment plot was characterized by a decrease of phanerophytes and an increase of hemicryptophytes. Fertilization had a beneficial effect on the growth in aboveground phytomass of M. sinensis, the dominant species. However, it did not cause a change in the total number of stems of M. sinensis. Annual increment of patch diameter of M. sinensis was estimated to be 6-8 cm on an average and there was no significant differecne in the growth rate of patch size between fertilized and nonfertilized plots. To estimate the aboveground phytomass of M. sinensis, several non-destructive parameters were examined. As a result, the patch size showed a high correlation with aboveground phytomass. Thus the patch size was suggested to be most applicable to its estimation. Diversity indices based on phytomass data of component species were increased slightly by fertilizatin, because relative dominance of some other species, especially of Artemisia princeps increased, while that of M. sinensis decreased. Fertilizer application resulted in a decrease in the total number of species.

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First Record of Three Loxodes Ciliates (Ciliophora: Loxodida: Loxodidae) from Korea

  • Kim, Ji-Hye;Kwon, Choon-Bong;Yoon, Jae-Sool;Shin, Mann-Kyoon
    • Animal Systematics, Evolution and Diversity
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    • v.25 no.3
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    • pp.301-308
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    • 2009
  • Three Loxodes ciliates collected from estuarine littoral, wetland and small pond in Korea, were identified as Loxodes kahli Dragesco and Njin$acute{e}$, 1971, L. magnus Stokes, 1887 and L. vorax Stokes, 1885. The descriptions for these species based on living and protargol impregnated specimens were given. Morphometry, illustrations and microphotographs were also provided. Diagnoses of three species are as follows. Loxodes kahli; size in vivo $160-300{\times}40-70\;{\mu}m$; oral area with reddish to brownish pigments; 6-11 macronuclei arranged linearly; 5-9 micronuclei located near macronuclei; 4-12 M$\ddot{u}$ller's vesicles; somatic kineties on right 18-20 and left 2 in number. L. magnus: size in vivo $250-470{\times}87-15\;{\mu}m$; body colored dark brown; 5-13 macronuclei; 8-13 micronuclei; 8-18 M$\ddot{u}$ller's vesicles; somatic kineties on right 23-26 and left 2 in number. L. vorax: size in vivo $70-160{\times}20-35\;{\mu}m$; oral area with brownish pigments; 2 macronuclei; 1 micronucleus located between macronuclei; 2-4 M$\ddot{u}$ller's vesicles; somatic kineties on right 18-20 and left 2 in number.

Grain Growth Behavior of (K0.5Na0.5)NbO3 Ceramics Doped with Alkaline Earth Metal Ions

  • Il-Ryeol Yoo;Seong-Hui Choi;Kyung-Hoon Cho
    • Korean Journal of Materials Research
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    • v.33 no.4
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    • pp.135-141
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    • 2023
  • The volatilization of alkali ions in (K,Na)NbO3 (KNN) ceramics was inhibited by doping them with alkaline earth metal ions. In addition, the grain growth behavior changed significantly as the sintering duration (ts) increased. At 1,100 ℃, the volatilization of alkali ions in KNN ceramics was more suppressed when doped with alkaline earth metal ions with smaller ionic size. A Ca2+-doped KNN specimen with the least alkali ion volatilization exhibited a microstructure in which grain growth was completely suppressed, even under long-term sintering for ts = 30 h. The grain growth in Sr2+-doped and Ba2+-doped KNN specimens was suppressed until ts = 10 h. However, at ts = 30 h, a heterogeneous microstructure with abnormal grains and small-sized matrix grains was observed. The size and number of abnormal grains and size distribution of matrix grains were considerably different between the Sr2+-doped and Ba2+-doped specimens. This microstructural diversity in KNN ceramics could be explained in terms of the crystal growth driving force required for two-dimensional nucleation, which was directly related to the number of vacancies in the material.

Morphological Description of Three Anaerobic Ciliates Unrecorded in Korea

  • Quoc Dung Nguyen;Novia Cahyani;Mann Kyoon Shin
    • Animal Systematics, Evolution and Diversity
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    • v.40 no.3
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    • pp.211-220
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    • 2024
  • During the surveys of ciliates from hypoxic habitats, three marine anaerobic species were found: Metopus spiculatus, M. vestitus, and Muranothrix felix. These species have not been previously recorded in South Korea and belong to the taxonomic classes Armophorea and Muranotrichea. The morphology of these species was examined by both microscopic observations of live specimens, and stained cells using protargol impregnations. Metopus spiculatus has the following characteristics: body size 80-110×25-35 ㎛ in vivo, beak-like structure at the end of preoral dome, ectosymbiotic bacteria covering cell surface, intracytoplasmic needle-shaped structures and the conspicuous tail end. Metopus vestitus has the following distinguishing characteristics: body size 95-130×25-45 ㎛ in vivo, a cone-shaped body, a covering of ectosymbiotic bacteria on its cell surface, intracytoplasmic needleshaped structures, somatic kineties arranged in 26-28 longitudinal rows, and a posterior part tapered into a tail. Muranothrix felix has the following characteristics: body size 100-130×20-30 ㎛ in vivo, elongated body with twisted neck region, bristle-like cilia protruding perpendicular to the cell margin, ectosymbiotic bacteria covering the cell surface, about 10 macronuclear nodules, and a long, stiffened caudal cilium.

Small Internal Antenna Using Multiband, Wideband, and High-Isolation MIMO Techniques

  • Kim, Sang-Hyeong;Jin, Zhe-Jun;Chae, Yoon-Byung;Yun, Tae-Yeoul
    • ETRI Journal
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    • v.35 no.1
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    • pp.51-57
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    • 2013
  • In this paper, a small internal antenna for a mobile handset is presented using multiband, wideband, and high-isolation multiple-input multiple-output techniques. The proposed antenna consists of three planar inverted-F antennas (PIFAs) that operate in the global system for mobile communication (GSM900), the digital communication system (DCS), the personal communication system (PCS), the universal mobile telecommunication system (UMTS), and wireless local area network (WLAN) bands with a physical size of $40mm{\times}10mm{\times}10mm$. A resonator attached to the folded PIFA creates dual resonances, achieving a wide bandwidth of approximately 460 MHz, covering the DCS, PCS, and UMTS bands; a meander shorting line is used to improve impedance matching. Additionally, a modified neutralization link is embedded between diversity antennas to enhance isolation, which results in a 6-dB improvement in the isolation and less than 0.1 in the envelope correlation coefficient evaluated from the far-field radiation patterns. Simulation and measurements demonstrate very similar results for S-parameters and radiation patterns. Peak gains show 3.73 dBi, 3.77 dBi, 3.28 dBi, 2.15 dBi, and 5.86 dBi, and antenna efficiencies show 56.15%, 72.15%, 68.59%, 52.92%, and 82.93% for GSM900, DCS, PCS, UMTS, and WLAN bands, respectively.

Community Size Structure of Zooplankton Assemblages in 29 Lentic Ecosystems on the Youngsan-Seomjin River Basin (2010~2011) (영산강, 섬진강 유역권내 29개 정수생태계의 동물플랑크톤 군집 크기 구조(2010~2011))

  • Kim, Hyun-Woo;La, Geung-Hwan;Park, Jong-Hwan;Song, Hyo-Jeong;Hwang, Kyung-Sub;Lim, Byung-Jin;Lee, Hak-Young
    • Korean Journal of Environmental Biology
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    • v.30 no.1
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    • pp.64-70
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    • 2012
  • This study compares the abundance and community structure of zooplankton organisms from the littoral and pelagic regions, and considers particularly trophic levels vs. zooplankton abundances. Zooplankton samples, collected every 3 months over a year from 2010 to 2011 at 29 temperate lakes and reservoirs, which belong to two different river basins (Youngsan and Seomjin River). The spatial pattern of rotifers was similar to that of total zooplankton abundance. This reflected the fact that rotifers strongly dominated the zooplankton community. There were considerable spatial variations in total zooplankton abundance (ANOVA, p<0.01), while there were no significant differences both in littoral and pelagic regions in abundance of zooplankton (ANOVA, p=0.205). The mean abundance of zooplankton in eutrophic systems was much higher than that of mesotrophic systems, while significant difference in number of species and diversity index were not shown in both trophic systems.

Genetic diversity in merozoite surface protein(MSP)-1 and MSP-2 genes of Plasmodium falciparum in a major endemic region of Iran

  • Heidari Aliehsan;Keshavarz Hossein;Rokni Mohammad B.;Jelinek Tomas
    • Parasites, Hosts and Diseases
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    • v.45 no.1 s.141
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    • pp.59-63
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    • 2007
  • Merozoite surface protein-1(MSP-1) and merozoite surface protein-2(MSP-2) were used to develop vaccines and to investigate the genetic diversity in Plasmodium falciparum malaria in Iran. Nested polymerase chain reaction amplification was used to determine polymorph isms of block 2 of the MSP-1 and the central domain of MSP-2 genes. A total of 67 microscopically positive P. falciparum infected individuals from a major endemic region, southeast Iran, were included in this trial. Nine alleles of MSP-1 and 11 alleles of MSP-2 were identified. The results showed that amplified product from these surface antigen genes varied in size and there was specific pattern for each isolate. Besides, regarding this pattern, 23 multiple infections with at least 2 alleles were observed. While the endemic regions of malaria in Iran is classified in low to moderate group, but extensive polymorphism was observed for each marker and the MSP-2 central repeat was the most diverse that could be considered in designing malaria vaccine.

The evaluation of the simultaneous flow rate for sizing the water supply piping in the office building (사무소 건물의 급수배관경 산정을 위한 동시사용유량에 관한 연구)

  • 이용화
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.4
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    • pp.511-517
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    • 1999
  • Determining the simultaneous flow rate in any particular section of piping is the important step in order to determine the size of water supply piping. Now we are using the diversity curve of common water closet in order to determine the simultaneous flow rate of water supply piping, but there is a difference between a determined flow rate of general water closet and that of water closet for water saving. This study aims to find out the fixture unit of a flush valve type water closet for water saving in office building, and to determine the correlation between the fixture units and peak flow rates on the basis of the probability theory. A flush valve type water closet for water saving that have a 7.5 second duration of flush operation with an average design flow rate 72 $\ell$/fin was considered. Simulation results indicate that the number 5 is shown to be reasonable to the fixture unit of water closet for water saving. And the design can be undersized considerably with the revised diversity curves using modified fixture unit.

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Plant Community Structure in the Sinhungsa - Wasondae Area, Soraksan National Park (설악산 국립공원 산림식생구조 - 신흥사~와선대지역 -)

  • 최송현;권전오;이경재
    • Korean Journal of Environment and Ecology
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    • v.10 no.2
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    • pp.270-282
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    • 1997
  • This investgation was performed to provide basic data for the management program of the Soraksan national park. Sixty plots were set up and surveyed in the Sinhungsa-Wasondae Area. The vegetation was divided into two communities, Pinus densiflora community and Quercus serrata community, according to the analysis of DCA ordination. It was found out that the succession of the Pinus densiflora comunity would proceed to Quercus serrata community of which components was dominant in understory layer and shrub layer. And it was found out that in the Quercus serrata community the Pinus densiflora being mainly big size in DBH would becomr dominant comtinuously. Shannon's diversity of both community were 1.2554 and 1.1134 respectively. The numbers of woody species per 100m$^{2}$ ranged 7 to 26, and the average number of woody species was 13.

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Effects of Shopping Value on Store Choice Behavior for Golf Wear (골프웨어 소비자들의 쇼핑가치가 의복선택기준과 점포선택행동에 미치는 영향에 관한 연구)

  • Park, Eun-Joo;Pyo, Hee-Soo
    • Fashion & Textile Research Journal
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    • v.8 no.5
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    • pp.545-551
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    • 2006
  • The purposes of this study were to examine the conceptual structure of shopping value, evaluative criteria of golf wear and store choice behavior, and to investigate the effect of shopping value and evaluative criteria of golf wear on store choice behavior. Data were obtained from 415 men and women aged 20-60 who had purchased golf wears living in Busan. The results of the study were as follows: Shopping value were composed of Hedonic shopping value and Utilitarian shopping value, and evaluative criteria of golf wear were consisted of Size/design.quality, Fitness/appropriateness of use, and Fashionability/brand. Stores choice behavior were composed of Atmosphere/salesperson, Diversity of product/service, Display/assortment, and convenience of location. Hedonic consumers tended to consider the price and display/assortment when they chose golf wear stores, and they were more likely to consider display/assortment mediated by fashionability/brand. But utilitarian consumers perceived less important diversity of product/service when they chose golf wear stores. Consumers who chose golf wear depending on fittness/design and quality patronaged stores offering diverse product/service.