• Korean journal of applied entomology
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• v.12 no.4 s.17
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• pp.139-142
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• 1973

Experiment was conducted to study resistance of rice varieties and lines originated from Korea and IRRI-sources to the white-backed planthopper, Sogatella furcifera Horvath. The nature of varietal resistance to the insects was evaluated from the viewpoints of nymphal period and adult emergence. The varieties Colombia, Muthumanikam and Pankhari-203 were resistant, the varieties CO-22, Mudgo and Vellailangalayan moderately susceptible, the other varieties all susceptible. Nymphal period and rate of adult emergence were significantly different according to the degree of resistance of the rice varieties. Nymphal period was short (about 10 days) in the susceptible varieties and long (about 14-16 days) in the resistant varieties. The .ate of adult emergence was significantly lower in the resistant varieties than in the susceptible varieties. The lower rate of adult emergence in the resistant varieties may be due to the fact that the insects were suffered higher nymphal mortality in the resistant than in the susceptible varieties.

• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.124-129
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• 2001

Crotalaria sessiflora is one of a few medicinal herbs among the legumes used as antitumor herb medicine but has lower seed germination and afterward seedling emergence. This study was carried out to elucidate the effects of cold stratification as presown treatment as well as $GA_3$, $KNO_3$ and acetone on its seed germination and seedling emergence. Cold stratification, $GA_3$, $KNO_3$ and acetone treatments were performed with different concentrations and period levels. Cold treatment was done under 14 hour red light illumination a day or darkness and the two others under darkness. On the basis of the best germination rate of each treatment, $GA_3$ and cold stratification treatments showed the highest germination rates at 0.1 mM but 12 hours and 2 week periods under darkness, respectively. $KNO_3$ and acetone treatments came out at 400 mM and 200 mM lasted for, respectively. The best germination rates from $KNO_3$ and acetone were comparatively higher than those from the former $GA_3$ and cold treatments. In evaluation of seedling emergence using the last two treatments, $KNO_3$ treated seeds were better performed than acetone treated seeds showed somewhat higher germination rate, implying that presown seed treatments must be evaluated by the combination with indoor and field tests.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.126-131
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• 1997

This experiment was conducted to obtain the basic information on ability of germination at low temperature with 26 cultivars of Korea including USA cultivars and to identify the optimal sowing depth in dry-direct seeded rice. Varietal difference in germination rate and days to emergence at low temperature($13^{\circ}C$) was observed. Average germination was 81.2% and range of germination rate showed 64.3 to 94.8%. In days to germination there was varietal difference. Average days to germination was 17.4 days and those range showed 14 to 24days. Negative high correlation was observed between the ability of germination and days to germination. Considering germination and days to germination. Jakwangdo, Nagdongbyeo, Cheongmeongbyeo, Calom, Anjungbyeo, Gyehwabyeo, Daegwanbyeo, Dongjinbyeo and Seohaebyeo were selected as a adaptable cultivar. High correlation was observed among the lodging index and sowing depth, stem diameter, height of central gravity, breaking strength. Seedling emergence was increased and days to emergence was shortened at the seeding depth of 1 and 3cm. Lodging index was decreased as seeding depth was deep and so the reasonable seeding depth would be around 3cm in direct seeded rice.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.4
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• pp.158-166
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• 2008

The pumpkin fruit fly, Bactrocera depressa (Tephritidae: Diptera), is one of the most important pests in Cucurbitaceae plants. This study was conducted to investigate the basic ecology of B. depressa, and to develop a forecasting model for predicting the time of adult emergence in early season. In green pumpkin producing farms, the oviposition punctures caused by the oviposition of B. depressa occurred first between mid- and late July, peaked in late August, and then decreased in mid-September followed by disappearance of the symptoms in late September, during which oviposition activity of B. depressa is considered active. In full-ripened pumpkin producing farms, damaged fruits abruptly increased from early Auguest, because the decay of pumpkins caused by larval development began from that time. B. depressa produced a mean oviposition puncture of 2.2 per fruit and total 28.8-29.8 eggs per fruit. Adult emergence from overwintering pupae, which was monitored using a ground emergence trap, was first observed between mid- and late May, and peaked during late May to early June. The development times from overwintering pupae to adult emergence decreased with increasing temperature: 59.0 days at $15^{\circ}C$, 39.3 days at $20^{\circ}C$, 25.8 days at$25^{\circ}C$ and 21.4 days at $30^{\circ}C$. The pupae did not develop to adult at $35^{\circ}C$. The lower developmental threshold temperature was calculated as $6.8^{\circ}C$ by linear regression. The thermal constant was 482.3 degree-days. The non-linear model of Gaussian equation well explained the relationship between the development rate and temperature. The Weibull function provided a good fit for the distribution of development times of overwintering pupae. The predicted date of 50% adult emergence by a degree-day model showed one day deviation from the observed actual date. Also, the output estimated by rate summation model, which was consisted of the developmental model and the Weibull function, well pursued the actual pattern of cumulative frequency curve of B. depressa adult emergence. Consequently, it is expected that the present results could be used to establish the management strategy of B. depressa.

• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.99-107
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• 2001

Germination of Codonopsis pilosula seeds and afterward their seedling emergence have been occasionally very poor due to their dormancy and structural defects. The study was done to determine the treatment effects of priming, $GA_3$, agitation and washing during and after priming, drying and water imbibition after drying on germination of its seeds and then of the successive three combined treatment after priming on the its seedling emergence to model its presown seed treatment. While agitation at the speed of 10 rpm was made or not, priming using $Ca(NO_3)_2$ and $GA_3$ under their different concentrations and light quality illuminated for 12 hours a day were done separately. Then their two best results were compared to determine the better one. Using the above determined best result, washing was done 3 minutes in the tap water or not, and drying of washed seeds was made under 4 different lights, and water imbibition of the dried seeds with differed period were successively done to deduce its presown seed treatment. In the comparison of the best germination rate of priming and $GA_3$, the former showed considerably higher rate than the latter; the priming treatment was done at agitated $Ca(NO_3)_2$ 150 mM solution under darkness or 12 hour red light illumination a day for 2 days. Washing after priming enhanced the rate compared to no-washing. Drying was the best way at which seeds washed were desiccated under $35^{\circ}C$ and 4 hour red light illumination. Water imbibition immediately before sowing must be made for 2 days. Seedling emergence rate was the highest at the seeds from successive 4 treatments, priming, washing, drying and water imbibition before sowing of two others, the priming and washing, or the priming, washing and water imbibition, meaning that its presown seed treatment must follow the procedure of the above 4 successive ones.

• International journal of advanced smart convergence
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• v.11 no.2
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• pp.1-6
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• 2022

With the emergence of the new era of the 4th industrial revolution, compute-bound workloads with large memory footprint like big data processing increase dramatically. Even in such compute-bound workloads, however, we observe bulky I/Os while loading big data from storage to memory. Although file I/O cache plays a role of accelerating the performance of storage I/O, we found out that the cache hit rate in such environments is not improved even though we increase the file I/O cache capacity because of some special I/O references generated by compute-bound workloads. To cope with this situation, we propose a new file I/O cache management policy that improves the cache hit rate for compute-bound workloads significantly. Trace-driven simulations by replaying file I/O reference logs of compute-bound workloads show that the proposed cache management policy improves the cache hit rate compared to the well-acknowledged CLOCK algorithm by a large margin.

• Journal of Environmental Science International
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• v.25 no.4
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• pp.557-566
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• 2016

In nine commercial watermelon cultivars, the effects of osmotic seed priming were evaluated for seed viability and seedling growth at different germination temperatures and field conditions. Generally, primed seeds showed improved germination rate and reduced time for emergence at different germination temperatures, as compared to untreated seeds. In particular, priming effect on seed germination was significantly high at $15^{\circ}C$, which is an environment normally resulting in poor germination. Depending on the watermelon cultivar, germination rate under low temperature ($15^{\circ}C$) was improved by up to 15~66% in primed seeds, as compared to untreated seeds. However, priming effect on germination was gradually reduced as the temperature reached to its optimum level for seed germination. Seed priming tended to improve the viability, fresh weight, and dry weight of watermelon seedlings, but its effect on seedling stage was not large, as compared to untreated seeds. Primed watermelon seeds showed improved emergence rate and facilitated germination in the field, but their seedling growth after 30 days from germination was not significantly affected. Our results indicated that seed priming can greatly improve the seed germination at poor temperature conditions in the watermelon.

• Journal of Korean Society of Forest Science
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• v.95 no.2
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• pp.174-176
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• 2006

The experiments were conducted by supplying hosts with natural food(chestnut, peach, Quince). The developmental difference of peach pyralid moth, Dichocrocis punctiferalis was examined in the laboratory under three different natural food regime. The periods of egg, larva and pupa were $6.01{\pm}0.07$, $12.23{\pm}0.03$ and $13.32{\pm}0.01$ days on the chestnut fruit, $6.21{\pm}0.01$, $18.69{\pm}0.02$ and $13.38{\pm}0.03$ days on the peach fruit and $7.02{\pm}0.04$, $22.62{\pm}0.04$ and $13.44{\pm}0.14$ days on the quince fruit, respectively. The growth of D. punctiferalis larva was better chestnut fruit than other tested fruits. The rates(%) of hatching, pupation and emergence were 94.0, 57.0 and 63.3 on the chestnut fruit, 89.2, 77.8 and 85.7 on the peach fruit and 79.6, 52.6 and 70.7 on the quince fruit, respectively. The survival rate(%) of D. punctiferalis from hatching to emergence were 31.0 on the chestnut fruit, 4.8 on the peach fruit and 14.3 on the quince fruit, respectively. The sex ratio (female: male) of all pupae obtained on the tested natural food fruits were 52.7 : 47.3. The sex ratio of D. punctiferalis reared on three difference food fruits were no significantly. It can be used a as the basic research for the study of D. punctiferalis.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.123.2-123.2
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• 2012

We investigate the solar flare occurrence rate and daily flare probability in terms of the sunspot classification supplemented with sunspot area and its changes. For this we use the NOAA active region data and GOES solar flare data for 15 years (from January 1996 to December 2010). We consider the most flare-productive eleven sunspot classes in the McIntosh sunspot group classification. Sunspot area and its changes can be a proxy of magnetic flux and its emergence/cancellation, respectively. We classify each sunspot group into two sub-groups by its area: "Large" and "Small". In addition, for each group, we classify it into three sub-groups according to sunspot area changes: "Decrease", "Steady", and "Increase". As a result, in the case of compact groups, their flare occurrence rates and daily flare probabilities noticeably increase with sunspot group area. We also find that the flare occurrence rates and daily flare probabilities for the "Increase" sub-groups are noticeably higher than those for the other sub-groups. In case of the (M+X)-class flares in the 'Dkc' group, the flare occurrence rate of the "Increase" sub-group is three times higher than that of the "Steady" sub-group. Our results statistically demonstrate that magnetic flux and its emergence enhance the occurrence of major solar flares.

• Korean Journal of Medicinal Crop Science
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• v.18 no.2
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• pp.93-97
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• 2010

Cultural practices of Asparagus cochinchinensis in highland area were performed for a potential medicinal crop. These studies were examined to propagation methods, planting densities, nitrogen treatments, and cropping years. The results are summarized as follows. The adequate number of buds per tuberous root was 4 for vegetative propagation because the number of tuberous root harvested was 16.8 and the yield was also the highest, exhibiting 1,060 kg/10a. The suitable planting time for vegetative propagation was later than early April. If the earlier tuberous roots were planted, the less they emerged. The highest emergence rate was obtained from the planting density of $30{\times}20cm$ as 97.2% while the yield was highest in the $30{\times}15cm$ density, exhibiting 1,883 kg/10a with emergence rate at 94.9. It seemed that the higher planting density promoted plant height growth and yield in Asparagus cochinchinensis. The highest fresh weight was recorded at 6 kg/10a of nitrogen fertilizer into the sandy loam soil compared to the level of 0, 3, 9 kg/10a. The yield was increased with cropping years. However, the proper harvesting time was the second year of cultivation because the rate of weight increase was maximized in the 2-year-old tuberous root. The yield in the third year was decreased as compared to that of the second year.