• Title/Summary/Keyword: Unit weight by area

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Effects of Deep Seawater on the Growth of a Green Alga, Ulva sp.(Ulvophyceae, Chlorophyta)

  • Matsuyama, Kazuyo;Serisawa, Yukihiko;Nakashima, Toshimitsu
    • ALGAE
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    • v.18 no.2
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    • pp.129-134
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    • 2003
  • In order to examine the effects of deep seawater (mesopelagic water in the broad sense) on the growth of macroalgae, the growth and nutrient uptake (nitrate and phosphate) of Ulva sp. (Ulvophyceae, Chlorophyta) were investigated by cultivation in deep seawater (taken from 687 m depth at Yaizu, central Japan, in August 2001), surface seawater (taken from 24 m depth), and a combination of the two. Culture experiments were carried out in a continuous water supply system and an intermittent water supply system, in which aerated 500-mL flasks with 4 discs of Ulva sp. (cut sections of ca. 2 $cm_2$) were cultured at 20$^{\circ}C$ water temperature, 100 $\mu$mol photons $m^{-2}{\cdot}s^{-1}$ light intensity, and a 14:10 light:dark cycle. Nutrient uptake by Ulva sp. was high in all seawater media in both culture systems. The frond area, dry weight, chlorophyll a content, dry weight per unit area, and chlorophyll a content per unit area of Ulva sp. at the end of the experimental period were the highest in deep seawater and the lowest in surface seawater in both culture systems. These values, except for dry weight per unit area and chlorophyll a content per unit area, for each seawater media in the intermittent water supply system were higher than those in the continuous water supply system. We conclude that not only deep seawater as the culture medium but also the seawater supply system is important for effective cultivation of macroalgae.

Assessment of agricultural Organic Matter Flow in a Rural Area (농촌지역에서의 농업 유기물 흐름의 평가)

  • 김진수
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.5
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    • pp.114-124
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    • 2000
  • The method to estimate agricultural organic matter flow on the regional scale was established and applied to a rural area in Chongwon-gun, Chungbok in 1996. The study area is of about 67$\textrm{km}^2$ and its population is about 7,000. The stocks and flows of organic matter are represented in dry weight per unit area and dry weight per unit area per year, respectively. the amount of inflow of organic matter indicates a possibility to cause environmental pollution. the amount of animal waste 767 kg/ha/yr account for 42 percent of total amount of organic waste 1,834 kg/ha/yr and therefore the environment in study area is greatly influenced by livestock. The decrease in recycling rate of animal waste form 100% to 70% has greatly increased the amount of disposal waste nearly twice, i.e., from 267 kg/ha/yr to 497kg/ha/yr . The results of this study demonstrate that appropriate animal population, increase in recycling of animal waste and preservation of agricultural land are necessary for environmental conservation of the study area.

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Comparison Between the Dynamic Properties and Noise Isolation Performances for a Floor Impact Isolation Pad (바닥충격음 완충재의 동적특성과 소음저감 성능 비교)

  • Yang, Soo-Young;Lee, Dong-Hoon;Hong, Boung-Kuk;Song, Hwa-Young;Lee, Joo-Wone
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.275-278
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    • 2005
  • In this study, the dynamic properties of a floor impact sound isolation pad expressed in terms of the natural frequency, the dynamic stiffness per unit area and the loss factor are measured by the resonant method. By using the measured dynamic properties, the vibration transmissibility diagram is obtained for each isolation pad, which is compared with the values tested by the impact sound sources at the room in an apartment. From the comparative results, it is found that the noise reduction Performances. of isolation pads are closely connected with the natural frequency and the dynamic stiffness per unit area.

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Effects of Methanol Extract of Ma-huang on Adipocyte of Epidiymal Fat in Rat Fed High Fat Diet (고지방 식이를 섭취한 흰쥐에서 마황의 메탄올 추출물이 체지방조직 세포에 미치는 영향)

  • 임경아;박용구;조여원
    • The Journal of Korean Medicine
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    • v.22 no.3
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    • pp.74-80
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    • 2001
  • Objectives : Ma-huang is a traditional Chinese medicinal herb, derived from Ephedra sinica Stapf and other Ephedra species, used to treat asthma, nose and lung congestion, and fever with anhidrosis. It contains 0.5-2.5% by weight of total alkaloids, of which ephedrine accounts for 30 to 90%. Recently, Ma-huang has been used as a source of ephedrine in many dietary supplements formulated for the treatment of obesity, since ephedrine has been found to be effective in inducing weight loss in the obese. In this study the effects of the methanol extract of Ma-huang on the adipocyte of epididymal and brown fat pads in rats fed a high fat diet for six weeks were studied. Methods : Male Sprague Dawley rats weighing an average 94g (4 weeks old) were fed either a regular diet (RE) or a high fat diet (HF), and the HF group was subdivided into a Ma-huang methanol extract (30mg/100g body weight) group (HF+MH). The weight of epididymal fat pad and brown adipose tissue were measured. The cell size and cell number per unit area of epididymal fat pad were investigated. Results : The yield weight of methanol extract of Ma-huang was 3.63mg per l00g of Ma-huang. The body weight gain of the HF group was similar with that of the HF+ MH but higher than that of the RE. The weights of the epididymal fat pads and brown adipose tissue of the RE group were lower than those of HF and HF+MH groups. The cell sizes and numbers per unit area of epididymal fat pads of the RE and HF+MH groups were larger than those of HF group. The cell numbers per unit area size of epididymal fat pads were the smallest in the RE group. Conclusions : It could be concluded that the Ma-huang extract has no effect on the epididymal fat pads in rats fed a high fat diet and the clinical application of Ma-huang for the treatment of obesity should be re-considered.

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Correlation, Regression, and Path Analysis between Yield and its Components in Tobacco (Nicotiana tabacum L.) (담배의 수량과 수량구성요소의 상관, 회귀 및 경로분석)

  • 김용암;유점호
    • Journal of the Korean Society of Tobacco Science
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    • v.3 no.2
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    • pp.115-122
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    • 1981
  • Data for this study were obtained from Burley 21 (Nicotiana tabacum L.) grown under various densities on the field in 1978 and 1979 at the Jeonju Experiment Station, Korea Ginseng & Tobacco Research Institute. Interrelations between yield and its components were statistically studied by correlation, regression, and pathway analysis. Correlation of yield with plant population was significant and positive. Quadratic functions for yield vs. plant population and the length of the largest leaf were fitted to the data. Multiple recession equation between yield and its components (leaf number ($X_1$), a leaf area ($X_5$), weight per unit leaf area ($X_9$), plant population ($X_14$)), was significant at the 5% level. Measuring the relative importance of its components on yield, plant population was 49.5%, weight per unit leaf area 25.3%, a leaf 15.6%, and leaf number 9.8%.

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Growth Response of Korean Lawngrass (Zoysia Japonica Steud.) Imposed by Different Plant Densities (재식밀도를 달리한 한국 잔디의 생장반응)

  • 심재성
    • Asian Journal of Turfgrass Science
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    • v.3 no.1
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    • pp.5-12
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    • 1989
  • Tiller numbers per Unit area were increased as plant density heightened followed by little difference in tiller number in 110 days after transplanting(ll0DAT), this being caused by the immediate increment of tiller since' 90DAT During the growth period, the greatest number of green leaves per unit area was attained in 90DAT of both 160-density and 200-density plots, and in l00DAT of 40-, 80-, and I 20-density plots. Thus, the period to reach the maximum green leaf number with the high plant density was earlier than with the' low plant density. The increment of plant density increased the DM weight of ahoveground part and, with 40-densitytreatment. DNI weight was increased 6.1 times as much up to 110DAT as up to 7ODAT but 2 to 2.9 times with other ehe'nsity treatments. The' rate of increase in stolon length was greatest at the period between 80 and 90DAT when DM weight of stolon showed a large increment. Meanwhile, the average number of stolon was 1.7 at 70DAT but was increased up to 10 at 110DAT probably due to accelerative appeance of Ist stolon branch since 8.0DAT. DM weight of stolon was found to exceeded that of root after 90DAT Thus it was concluded that, when turfs is estahlished from sprig. it may be desirable for first mowing practice to be made at least within l00 days after planting.

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Effects of Black Polyethylene Film Mulching and Planting Density on Growth and Yield of Rehmannia glutinosa Libosch. (흑색비닐 피복 및 재식밀도가 지황의 생육 및 수양에 미치는 영향)

  • 김인재;김민자;남상영;이철희;손석용;박상일
    • Korean Journal of Plant Resources
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    • v.16 no.2
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    • pp.118-122
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    • 2003
  • These studies were carried out to clarify the effects of black P.E. mulching and planting density on the growth and rhizome yield of Jihwang #1, a new high yielding Rehmannia glutinosa variety. Emergence ratio was higher 3.1% in mulching than in non-mulching, but was not affected by planting density. Plant height and fresh leaf weight per plant were increased by mulching and at lower planting density. However, the fresh leaf weight per unit area was increased at higher planting density. Dry rhizome weight was increased 28% in mulching than that of non-mulching. Dry rhizome weight per plant was increased, but that of per unit area was decreased at lower planting density.

Seasonal Species Composition and Fluctuation of Fishes by Beam Trawl in Yeoja Bay (빔트롤을 이용한 여자만 어류의 계절별 종조성과 변동)

  • Lee, Sun-Kil;Seo, Young-Il;Kim, Joo-Il;Kim, Hee-Yong;Choi, Mun-Sung
    • Korean Journal of Ichthyology
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    • v.23 no.3
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    • pp.206-216
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    • 2011
  • To investigate seasonal and yearly variation of fishes composition in Yeoja Bay of Korea, fisheries survey were carried out using beam trawl from 2006 to 2009. A total of 44 fish species were collected. The major dominant species were Pennahia argentatus, Thryssa adelae, Thryssa kammalensis and Cynoglossus joyneri, which were occupied over 63% total individuals, and 50% of wet weight. The diversity index (H') was about 1.62 (1.46~1.77) by seasons, and seasons of similarity by fishes were divided into two groups, which were March with December and June with September. ANOVA test showed that there were not significant difference between individuals and catch weight (kg) per unit area (km$^2$) by year and season, except for catch weight per unit area by season.

Effect of Seedling Characters on the Growth of Ginseng Plant on Field. .1. Relationship between Seedling Weight and the growth of ginseng plant on field. (묘삼의 소질이 본포에서의 생육에 미치는 영향 제 3보 황삼의 중량과 본포5.6연근의 인삼생육과의 관계)

  • 이성식;천성용;김오태;이창화
    • Journal of Ginseng Research
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    • v.8 no.1
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    • pp.57-64
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    • 1984
  • In order to clarify an effect of seedling weight on the growth pattern of ginseng, seedlings ranged from 0.4g plant to 1.8g plant were transplanted, and then the characters of 5- and 6-year-old ginseng were investigated. The characters of root and leaf, such as length and diameter of main root, root weight, leaf area, and leaf dry weight of 5- and 6-year-old ginseng originated from large seedlings were superior as compared with those from small seedlings, and percentage of missing plant was increased with the increase of seedling weight. There were, however, no significant difference in stem length, stem dry weight, number of seeds per plant and number of palmate leaves and leaflets per plant in 5- and 6-year-old ginseng and these characters were not affected by the weight of seedings transplanted. Root field per unit area was higher in seedings of above 0.6g/plant than in small seedlings.

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Development of Weight Type Snowfall Gauge and Observation (중량식 강설량계 개발과 관측)

  • Lee, Bu-Yong
    • Journal of Environmental Science International
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    • v.18 no.3
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    • pp.255-261
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    • 2009
  • We need water equivalent unit data of snowfall for the purpose of forecast and hydrology related research area. This study developed new method of automatic recording snowfall as weight unit. The instrument designed for measuring weight of snowfall by stain-gauge loadcell. Field test of instrument carried out at Daegwallyeong Obs. Station from 22 Jan. to 22 Feb. 2007. During observation period there is 15.3 cm snow depth and 16.0 mm of accumulated water equivalent depth at Daegwallyeong Obs. Station on 13 to 14 Feb. 2007. But the instrument of this study recorded 22.1 mm of water equivalent depth. It is not easy to explain difference between Daegwallyeong and this study. Because this study is only one case of comparison of snow measurement and there is very little amount of snow observation research. The density of snowfall calculated from 0.09 to $0.15g/cm^3$ from the observation data of 13 to 14 Feb. 2007. There is high relation between radar echo and snowfall amount measured by weight unit. It can supports forecast of snowfall and development of numerical model for forecast.