• Title/Summary/Keyword: evenness

Search Result 472, Processing Time 0.026 seconds

Variation in abundance and species composition of fishes in eelgrass (Zostera marina) bed and around Geomundo (거문도 연안 잘피밭과 주변해역의 어류 종조성 및 양적변동)

  • SIN, Kyung-Soo;HAN, Kyung-Ho;BAEK, Jeong-Ik;LEE, Sung-Hoon;LEE, Won-Kyo
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.51 no.4
    • /
    • pp.484-492
    • /
    • 2015
  • The purpose of this study is to compare the ichthyofauna between the eelgrass bed waters located in the open sea and the nearby sea free of eelgrass, and this study collected a total of 26 species. Comparing the fish collected on the eelgrass bed (St.2) of Geomun-do coast with the fish collected on the coastal waters (St.1) void of the nearby eelgrass bed, the fish collected from the eelgrass bed included 19 species, 413 individual with 16,110.6g in weight while the fish collected from the coastal waters void of the eelgrass bed included 19 species, 290 individuals with 12,961.5g in weight. Accordingly, it was found that the population size and biomass of the fish collected from the eelgrass bed were higher than the coastal waters void of the eelgrass. This study could identify that diversity, richness, evenness index except dominance were also much higher even in the result of cluster analysis.

Analysis of Some Desert Ecosystems Vegetation in Abu Dhabi Emirate, United Arab Emirates. Effect of Land Use

  • Mousa, Mohamed Taher;Ksiksi, Taoufik Salah
    • Journal of Forest and Environmental Science
    • /
    • v.25 no.1
    • /
    • pp.49-55
    • /
    • 2009
  • The present study analyses the effect of land use on the vegetation of some desert ecosystems in Abu Dhabi, United Arab Emirates (UAE). Three sites were selected to represent different types of land use, inside Umm Al-Banadeq forest, outside the forest and along Abu Dhabi-Al Ain Trucks Road. In total, fifty-two stands were examined; including a matrix of 14 species ${\times}$ 52 stands. Based on species cover data, stands were classified using TWINSPAN and ordinated using DCA. Four vegetation groups were generated at level three of classification. Zygophyllum mandavillei was dominant in most vegetation groups; Heliotropium bacciferum dominated vegetation groups inhabited the forest. Species richness, species turnover, relative evenness and relative concentration of dominance of forest vegetation groups were 2.8, 5.7, 0.7, and 2.0, respectively. The differences were attributed to both natural variability and forestry-induced changes, including change in land use, drainage and ploughing and shading by trees. Vegetation group inhabited Abu Dhabi-Al Ain Trucks Road, that were dominated by Haloxylon salicornicum and Zygophyllum mandavillei have high total cover (8.8 m per $m^{-1}$). Most community and vegetation attributes were significantly higher inside the forest than outside. Human interventions and environmental factors affected species diversity and abundance of these communities.

  • PDF

The Secondary Vegeation and Sucession of the Forest Fire Area of Nae-Hak Dong, Mt. Palgong (팔공산 내학동일대의 산화적지의 이차식생과 천이)

  • Cho, Young Ho
    • The Korean Journal of Ecology
    • /
    • v.6 no.1
    • /
    • pp.22-32
    • /
    • 1983
  • The paper is investigation of the secondary vegeation and succession at the forest fire area in Mt. Palgong. The survey was carried out from April, 1981 to Stempter, 1982. The floristic compositions were as follows: 50 families, 116 genera, 127 species, 15 varieties and 3 formae(145 kinds). Among them, the floristic composition of the pine floor vegetation of the unburned area was 43 families, 80 genera, 88 species, 10 varieties and 1 forma(99 kinds), and that of the secondary vegetatiion after forest fire was 46 families, 106 genera, 120 species, 14 varieties and 3 formae(137 kinds). Index of similarity between the burned and unburned area was 0.77. The biological type succeeded in $H-D_1-R_5$type, and the erect form(s) was prevailed. Carex humilis var. nana, Miscanthus sinensis var. purpurascens, and lespedeza cyrtobotrya were dominant species in the $ B_1; and; B_2$ area of the seventh year after forest fire. In the degree of succession, species diversity, and evenness index, DS, H, and e of the $B_1$ area were higher than those of the $B_2$ area. In the soil properties, it assumed that pH, total nitrogen, and available phosphores of the burned area were nearly recovered to those of the unburned area.

  • PDF

Changes in the Macrobenthic Community in Sihwa Tidal Flat After Operation of the Tidal Power Plant (조력발전소 가동 후 시화갯벌의 대형저서동물군집 변화)

  • Kim, Minkyu;Koo, Bon Joo
    • Ocean and Polar Research
    • /
    • v.38 no.4
    • /
    • pp.315-324
    • /
    • 2016
  • In this study, we investigated changes in the macrobenthic community in Sihwa tidal flat before and after the operation of a Tidal Power Plant (TPP). In order to investigate changes in the macrobenthic community structure, field surveys were conducted at eighteen stations in 4 transect lines every September from 2011 to 2015. Mean density of macrobenthos decreased to $116ind./m^2$ in 2015 from $1,602ind./m^2$ in 2011. While the mean density of macrobenthos has decreased, species richness and biomass have gradually increased. The species diversity and SEP (Shannon-wiener Evenness Proportion) have also gradually increased over time since the operation of the TPP. The macrobenthic community in Sihwa tidal flat was divided into 4 groups on a yearly base. Before the operation of TPP, opportunistic species such as Neanthes succina and Polydora cornuta largely contributed to the structure of the macrobenthic community, while equilibrium species such as Periserrula leucophryna and Scopimera globosa contributed after the operation. With the operation of TPP, the macrobenthic community has rapidly recovered and this might be related to improvement in the quality of water and sedimentary environments as a result of an increase in water mass volume exchanged through the TPP gate.

Bio-polishing and Silket Treatment of Cotton Yarns (면사의 효소가공 및 실켓 가공)

  • Bae, Young-Hwan;Lee, Ji-Wan;Son, Young-A;Kim, Ju-Hae;Kwon, Mi-Yeon;Kim, Eui-Hwa;Lee, Seung-Goo
    • Textile Coloration and Finishing
    • /
    • v.20 no.4
    • /
    • pp.15-20
    • /
    • 2008
  • The cotton yarn was subjected to bio-polishing treatment with three commercial enzymes(Cellusoft L, Denimax-991L and Denimax-acid) to remove the fuzz on the cotton yarn. Also, enzyme treated cotton yarns were compared with singeing cotton yarns. Experimental variables of enzyme treated cotton yarn were as follow: concentration of enzyme solution and NaOH, dipping time, and processing temperature. The enzymatic treatments were evaluated by analyzing the effect on yarn count, twist contraction, evenness and tenacity. As the results, enzymatic treatment on cotton yarn induced same effects as the traditional singeing treatment. Also, silket treatment of cotton yarn after bio-polishing enhanced the tensile properties of the cotton yarn.

Characteristic Analysis of Planetary Gear Set of Hydromechanical Transmission System of Agricultural Tractors

  • Park, Young-Jun;Kim, Jeong-Gil;Lee, Geun-Ho
    • Journal of Biosystems Engineering
    • /
    • v.41 no.3
    • /
    • pp.145-152
    • /
    • 2016
  • Purpose: This study aims to establish the effect of pinhole position errors in the planet carrier of a planetary gear set (PGS) on load sharing among the planet gears in the hydromechanical transmission (HMT) system of an agricultural tractor. Methods: A simulation model of a PGS with five planet gears was developed to analyze load sharing among the planet gears. The simulation model was verified by comparing i ts r esults w ith those of a model developed in a previous s tudy. The verified simulation model was used to analyze the load-sharing characteristics of the planet gears with respect to the pinhole position error and the input torque to the PGS. Results: Both simulation models had identical load magnitude sequences for the five planet gears. However, the load magnitudes on the corresponding planet gears differed between the models because of the different stiffnesses of the PGS components and the input torques to the PGS. The verified simulation model demonstrated that the evenness of load sharing among the planet gears increases with decreasing pinhole position error and increasing input torque. Conclusions: The geometrical tolerance of the pinhole position should be properly considered during the design of the planet carrier to improve the service life of the PGS and load sharing among the planet gears.

A Study on the Standardization of Fineness Measurement for the Thermal Insulator of Military Textiles (방한용 화섬솜의 섬도 측정방법의 표준화에 관한 연구)

  • Hong, Seong-don;Kim, Byung-soon
    • Journal of Korean Society for Quality Management
    • /
    • v.43 no.3
    • /
    • pp.253-272
    • /
    • 2015
  • Purpose: The purpose of this study is to enhance the reliability of quality inspection by standardize the fineness test method of the thermal insulator of military textiles Methods: We have measured the thermal insulator of military textiles by microscope with three different ways and the effectiveness of their difference were analyzed by one-way layout design. Results: We have suggest the standardized the fineness test method of the thermal insulator of military textiles through advanced research. As a result we have verified hollow ratio of heat insulating fiber affect fineness test methods. The fineness test method for the thermal insulator applied with different methods following hollow ratio. We have verified that when the hollow ratio over 90%, the fineness of the thermal insulator measured from fiber-length, if it has over 80%, the cross-section length of hollow and if it has less 80%, the cross-section area of hollow is applied, respectively. Conclusion: This study indicated that the test method of fineness shows high reliability. Heat insulating fibers which have high evenness shows narrow variations(5/% or less, only CV 25%) irrespectively under different testing equipment or institute. Based ons the results, we have suggest the standardization of test methods for fineness by microscope method and produced the registration of Group Standard in Korean Standards Association.

Effect of High Solid Coating and Water Absorption Uniformity of Base Paper on Print Mottle - Evaluation of print mottle with PEA module - (고농도 도공과 원지의 흡수특성이 인쇄모틀에 미치는 영향 - PEA Module를 이용한 인쇄모틀 평가 -)

  • Yoo, Sung-Jong;Cho, Byoung-Uk;Kim, Yong-Sik;Lee, Yong-Kyu;Lee, Se-Hyun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.39 no.2 s.120
    • /
    • pp.17-24
    • /
    • 2007
  • PEA(Print Evenness Analyzer) Module can be utilized as a tool to evaluate print mottle. The tester is de-signed to measure the uniformity of liquid penetration into paper at very short contact time. To evaluate effects of base paper properties on print mottle, the experiments were performed with 3 types of base pa-per whose sizing degree, roughness and porosity were varied. Coated papers were produced with high solid coating color (70%) and low solid coating color (67%). Uniformity of water absorption into base paper and coated paper was measured with PEA. It was found that, in order to minimize print mottle, base paper shall be produced with a high sizing degree and low roughness and the concentration of coating color shall be kept as high as possible, providing that it has proper rheology properties for coating process.

Seasonal Variation in Seaweed Community Structure in the Subtidal Zone of the Southern Part of the East Coast of Korea (동해 남부 해역 조하대 해조류 군집구조의 계절적 변화)

  • Han, Su Jin;Hwang, Youg Hun;Son, Min Ho;Choi, Han Gil;Jang, Jae Gil
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.51 no.5
    • /
    • pp.571-578
    • /
    • 2018
  • Seasonal variability in algal community structure of the subtidal zone was examined at four study sites on the southeastern coast of Korea from February to November 2016. A total of 81 species of algae (8 green, 12 brown, and 61 red) were indentified. During the study period, the greatest number of species was observed at Sinamri (57 species) followed by Daesongri (50 species), Dongbaekri (47 species) and Gangyangri (42 species). Of the six functional seaweed forms, the coarsely-branched form was the most dominant, accounting for about 43% of the total species at Daesongri. The annual average biomass in wet weight varied from $700.59g/m^2$ at Sinamri to $1,712.45g/m^2$ at Daesongri. The parameters of seaweed community structures were as follows: dominance index (DI), 0.30-0.54; richness index (R), 4.92-7.05; evenness index (J'), 0.54-0.72; and diversity index (H'), 2.05-2.91.

Characterizing Yarn Thickness Variation by Correlograms

  • Huh You;Kim Jong S.;Kim Sung H.;Suh M. W.
    • Fibers and Polymers
    • /
    • v.6 no.1
    • /
    • pp.66-71
    • /
    • 2005
  • The surface evenness and texture are closely related with the irregularity of yam thickness. Besides, yam thickness variation has an important role to influence the yam performance and the textile process efficiency. Thus, the information not only on the yam thickness, but also on the short- term irregular characteristics that have not been known before is required for enhancing the qualities of textile products. This paper reports the results of a study about the yam thickness and its variation for various types of yam on the basis of a new measurement system applying a laser slit beam as a light source. The new method delivers effective information on the irregularity. The analysis of the measured signal confirms that the visual shade created by the yam doubling and twisting can be measured and the yam thickness characteristics can be represented by corre­lograms. Depending on yam types, correlograms have different shapes and can be approximated to an exponentially decaying function with or without fluctuating magnitude. In addition, the effective information on the yam irregularity can be influ­enced by the sampling length interval of the measuring device used for tests.