• Water for future
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• v.21 no.1
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• pp.77-86
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• 1988

The main objective of this paper is to study the application of runs to the analysis of hydrologic data. The stochastic structure of annual hydrologic data is investigated using the statistical properties of run-length for various truncation levels. Observed relative frequencies of run-length at each station are copared with the calculated and approched to the calculated. Also, it can be shown to estimate the durations of wet and dry years by the probabilities of run-length for a given truncation level. Annual precipitation data were obtained from the stations where have relatively long records, and stream flow data were generated by Markov model. The results of hypothesis test with run-lengths show independence of annual hydrologic series and Markov model can be applied to generate annual stream flow at Hyunpung, Waekwan and Gyuam.

• 한국해양학회지
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• v.30 no.5
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• pp.403-412
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• 1995

The present study was performed to determine th growth and production of Mactra veneriformis on the Songdo tidal flat off Inchon. west coast of Korea. Monthly samples were collected from Marc 1989 to September 1990. The size distributions of shell length showed unimodal patterns from March to August 1989. The binodal pattern after September 1989 indicated a recruitment of young clams during this period. The density fluctuated irregularly, but showed a decreasing pattern over time on the whole. The density of the year class 1989 increased markedly after February 1990. The growth in shell length showed three phases during a year, a fast growth phase in spring, a slow growth phase in summer and autumn, and a lag phase in winter. The annual increment in shell length reduced with age. The flesh dry weight showed a peak in late spring just before the spawning period, and another peak in autumn. The length of annuli and the back-calculated flesh dry weight were used to describe the annual growth. The growth in shell length fitted to the von Bertalanffy model and the flesh dry weight to the Gompertz model. The absolute growth rate of the shell length reduced gradually with age. The year class 1985 had the highest L, and the yeat class 1986 the lowest L. The annual growth in weight showed a typical sigmoid curve. The growth rate was maximum at the age of 2 to 3. Year classes of 1984 and 1985 had higher values of W and higher absolute growth rates than those of 1986 and 1987. Maximum absolute growth rates of 1986 and 1987 year classes were recorded at younger ages than 1984 and 1985 year classes. The annual relative growth rates of length and weight decreased exponentially with age. Biomass in flesh dry weight increased till spring and thereafter decreased progressively. Maximum biomass was 134.6g m/SUP -2/ in August 1990. The biomass of 1989 yeat class occupied highest proportion in total biomass. Annual production in flesh dry weight from March 1989 to March 1990 was 67.9 g m/SUP -2/ year/SUP -1/. Cumulative production of 1989 year class was highest among all year classes, and that of year class 1984 was lowest. The production is high in spring and autumn, and very low in summer and winter.

• Korean Journal of Organic Agriculture
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• v.7 no.2
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• pp.179-188
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• 1999

The effects of earthworm casts as a plant growth media on the growth of orchardgrass seedlings and the changes of physico-chemical properties in worm casts mixture soils were investigated during the growth period of 1998. Worm casts were mixtured with vermiculite, perlite and peat moss, and mixture ratios of worm casts with commercial recommended soil were 100:0(control), 75:25, 50:50, 25:75, and 0:100, respectively. The results were obtained as follows; 1. Plant length(PL) was increased in higher mixture ratios of worm casts and peat moss than those of other mixture ratios of commercial recommended soils. 2. Number of tillers(NT) were significantly increased in mixture ratios of worm casts and peat moss(50:50) and 100% of vermiculite. 3. Root length(RL) was significantly differences between mixture ratios at the worm casts, and the highest value was obtained at all mixture ratios of worm casts and perlite. 4. Dry weight of leaf(LW) was not significantly differences at mixture ratios of 50:50 in all treatments. Especially, between the mixture ratios of worm casts with peatmoss(25:75) and peat moss(75:25) were not significantly differences in dry weight of leaf(LW). The highest value of dry weight of leaf(LW) was obtained at mixture ratios of peat moss and worm casts. 5. Dry weight of tillers(SW) was not significantly differences at mixture ratios of 50:50 in all treatments, and peat moss(75:25) and vermiculite(75:25), respectively. 6. biological yield(BY) at all treatments were increased by yield components of dry weight of tillers(SW), dry weight of root(RW) and length of root(RL). 7. The biological yield of orchardgrass seedlings was greatly increased with mixture ratios of worm casts and peat moss over the 50%.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.1
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• pp.67-72
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• 1995

To select the highest yield soiling type forage, the yield performance of selected sorghum-sudangrass hybrids imported in 1992 have been evaluated at Chonnam region. The soiling type hybrids used in this experiment were TE-haygrazer, FP-5 Sudan, Sweet sioux V, and X -78050. Three different cuttings were done on July 6, August 6 and September 16 in 1992. This trial was arranged as a randomized complete block design with three replications under taken over a period 5 months from May to September in 1992. The results of this experiment were summarized as follows: The hybrids tested were not significantly different by plant height, leaf blade length, leaf blade width and stem diameter. In the first cutting, dry matter yield of FP-5 Sudan was the highest. In the second and third cutting, dry matter yield of Sweet sioux V was the highest among hybrids. The contents of crude protein, hemicellulose, relative feeding value(RFV), and amino acid were the highest by the first cutting, but NDF and ADF were shown the lowest.

• Journal of Life Science
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• v.11 no.2
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• pp.166-172
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• 2001

Various types of the seeding of bottle gourd widely used as a rootstock of watermelon has been required to satisfy the farmers need. The study was done to determine the effect of light quality of blue, red and far-red lights treated with light emitting diodes on growth and morphology of bottle goured seeding and chlorophyll content of its cotyledons. The lights were treated in the growth chamber for 7 days to the seeding elapsed 8 days after sowing under natural condition, and 64 hole trays with commercial bedsoil. Plant height, length and diameter of hypocotyl, leaf area of cotyledon and first true leaf, its leaf length, number of true leaves, fraction and total dry weight were measured. Red light shortened and slenderized the hypocotyl, which lengthened by far-red light and thickened by blue light. Plant height was declined in order of far-red light treatment, blue and red lights mainly due to difference of hypocotyl length, Area and length of the first true leaf became smaller and shorter under far-red light than under the other lights. However, blue light increased leaf area of cotyledons. Two cultivars cv. Yongjadaemok and cv. Kunghap had different response to the light treatments in total seedling dry weight(dw); far-red and red light treatments showed the greatest and the least dw of hypocotyl, respectively, while blue and red lights did the greatest dw of the other organs. Among the ratio of each organ dw to total dw, those of hypocotyl and true leaves were different between the light treatments; the highest ratio of hypocotyl dw to total dw was observed in far-red light treatment but the lowest was in red light treatment. Those of the true leaves were the lowest in far-red light and similar response in blue or red light treatment. Chlorophyll content of cotyledons was decreased in order of red light treatment, blue and far-red lights, meaning that short period light treatment may influence photosynthesis of seeding and afterward its growth.

• Wind and Structures
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• v.24 no.6
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• pp.579-611
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• 2017

Bora is a strong, usually dry temporally and spatially transient wind that is common at the eastern Adriatic Coast and many other dynamically similar regions around the world. One of the Bora main characteristics is its gustiness, when wind velocities can reach up to five times the mean velocity. Bora often creates significant problems to traffic, structures and human life in general. In this study, Bora velocity and near-ground turbulence are studied using the results of three-level high-frequency Bora field measurements carried out on a meteorological tower near the city of Split, Croatia. These measurements are analyzed for a period from April 2010 until June 2011. This rather long period allows for making quite robust and reliable conclusions. The focus is on mean Bora velocity, turbulence intensity, Reynolds shear stress and turbulence length scale profiles, as well as on Bora velocity power spectra and thermal stratification. The results are compared with commonly used empirical laws and recommendations provided in the ESDU 85020 wind engineering standard to question its applicability to Bora. The obtained results report some interesting findings. In particular, the empirical power- and logarithmic laws proved to fit mean Bora velocity profiles well. With decreasing Bora velocity there is an increase in the power-law exponent and aerodynamic surface roughness length, and simultaneously a decrease in friction velocity. This indicates an urban-like velocity profile for smaller wind velocities and a rural-like velocity profile for larger wind velocities. Bora proved to be near-neutral thermally stratified. Turbulence intensity and lateral component of turbulence length scales agree well with ESDU 85020 for this particular terrain type. Longitudinal and vertical turbulence length scales, Reynolds shear stress and velocity power spectra differ considerably from ESDU 85020. This may have significant implications on calculations of Bora wind loads on structures.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.3
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• pp.219-221
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• 1995

Data on productive and reporductive performance of native cows maintained at Savar Dairy Farm, Central Cattle Breeding Station (CCBS), Savar, Dhaka, were collected from the periods of 1980-1988. The mean calving to first breeding during the second parity was longer (p < 0.01) than the fourth and fifth parities (152 vs 105 and 96 days respectively). There was no difference on the parameters like first breeding to conception, service period, gestation length, number of services per conception and total milk yield over the parities. The mean calving interval during the second parity was longer (p < 0.05) than the fourth and fifth parities. The mean lactation length during the first parity was longer (p < 0.01) than those of second, third, fourth and fifth lactations (317 vs 237, 266, 250 and 247 days respectively). The mean per day milk yield during the first lactation was lower (p < 0.01) than those of second, third, fourth and fifth lactations (1.88 vs 2.55, 2.75, 2.54 and 2.57 kg respectively). The mean dry period was longer in first lactation (p < 0.05) compared to third and fifth lactations (209 vs 141 and 129 days respectively).

• Asian Journal of Turfgrass Science
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• v.4 no.2
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• pp.77-83
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• 1990

The effect of bio-fertilizer, which was manufactured poultry manure, on the fall performance of Korean lawngrass was determined on a clay loam soil. Plant length was characterized by increasing the amount of bio-fertilizer applied. This trend was also true in dry matter yield of tops during the experimental period from August 31 through October 30. Both tiller numbers and stolon length steadily increased with increasing amount of bio-fertilizer applied, and 40m/t application of bio-fertilizer was found to be most effective on both components. performance shown on November 5 was prominent for both green leaf and root weights when the increased amount of bio-fertilizer was applied. Korean lawngrass had three times as much green leaf weight with 40m/t application of bio-fertilizer as with other treatments. Several functions of increment of above- ground part components caused by increasing root weight, which is greatly affected by bio-fertilizer application, was discussed. Turf quality was much improved by applying bio-fertilizer, indicating that this fertilizer might play an improtant role in respect of soil structure, water retention etc.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.1
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• pp.91-99
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• 1996

About 7.7 million tons of straw dry matter are being rotten during the monsoon. The objective of this trial was to develop a technique to preserve straw under wet condition. To simulate the moisture content of wet straw, a dry straw was deeped overnight in water. After draining the excess water, the wet straw(668 g moisture $kg^{-1}$) was divided into twenty fractions and preserved with 0, 30, 50 ro 70 g urea $kg^{-1}$ dry matter for either of 30, 60, 90, 120 or 180 days in sealed plastic container. Considering the colour, smell, fungal infestation and pH, the wert straw was preserved excellently up to 180 days when 50 or 70 g of urea per kg DM was used. Urea preservation increased the crude protein contents of straw by 3.6 to 6.4 times (174 to $364g{\cdot}kg^{-1}$) over that of the dry straw ($48g{\cdot}kg^{-1}$). Although the NDF content of straw was not effected by the level of urea or by the length of the preservation period, but the ADF content increased (p > 0.05) by 0.086 to $0.889g{\cdot}kg^{-1}$ straw DM for each g increase in the urea level. At 48 hours, the DM degradability of dry straw was $350g{\cdot}kg^{-1}$, which increased to $633g{\cdot}kg^{-1}$ when preserved with 50 g urea $kg^{-1}$ for 180 days. For the same straw, both the rate(0.0388 vs. 0.0136 fraction $h^{-1}$), the extent(717 vs. $631g{\cdot}kg^{-1}$) of straw degradation and the estimated ME(9.55 vs. $6.51MJ{\cdot}kg^{-1}$ straw DM) were higher in the preserved than the dry straw.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.3
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• pp.176-182
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• 2022

The aim of this study was to investigate dry matter productivity and nitrate nitrogen content in the growth stages of barnyard millet (Echinochloa esculenta) cultivated for feed, which was treated with different nitrogen fertilization levels. An early variety of barnyard millet (cv. Shirohie) was used for the test, and the different treatments with nitrogen fertilizer were as follows: 50% (N-40 kg/ha, T1), 100% (N-80 kg/ha, reference amount, T2), 150% (N-120 kg/ha, T3), 200% (N- 160 kg/ha, T4), 250% (N-200 kg/ha, T5), and 300% (N-240 kg/ha, T6). Sowing was done on May 13, 2021 and plants were harvested for four stage; vegetative stage, elongation stage, heading stage, and milk stage. The length of the millet increased significantly as the amount of nitrogen fertilization increased during the harvest period (p<0.05), but the difference was insignificant during the milk stage (p>0.05). Moreover, barnyard millet dry matter yield increased significantly as the levels of nitrogen fertilization increased (p<0.05), but there was no significant difference in dry matter yield among nitrogen fertilization levels during the heading stage (p>0.05). Chlorophyll also was significantly higher in T5 (250%) at all harvesting times, whereas nitrate nitrogen content was highest at the vegetative stage, gradually decreased as growth progressed, and lowest at the milk stage. Finally, as the nitrogen fertilization levels increased, the nitrate nitrogen content was significantly higher in all treatment groups (p<0.05). Therefore, our results suggest that the most appropriate nitrogen fertilizer levels is between 150%-200%, considering the dry matter yield, feed ingredients and nitrate nitrogen content in barnyard millet for feed.