• The Plant Pathology Journal
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• v.17 no.3
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• pp.159-163
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• 2001

Influence of soil temperature [accumulated degree-day for the base temperature $5^{\circ}$($\textrm{DD}_5$)] on the development of Meloidogyne arenaria were studied in a winter grown oriental melon greenhouse in Seongju, Korea. Egg masses were first observed on roots at the accumulation of 565 $\textrm{DD}_5$(40 days after transplanting), suggesting that the nematode has completed the first generation in 40 days. Second-stage juveniles (J2) densities were lowest at 863 $\textrm{DD}_5$ in April, first increased at 1,334 $\textrm{DD}_5$ in May, peaked at 2,951 $\textrm{DD}_5$ in July, and decliner thereafter. Development of egg masses and J2 density in soil revealed that M. arenaria could develop in 7-8 generations in a year in the greenhouse. Degree-day monitoring, therefore, could aid to predict nematode development in soil and can be valuable tool a to develop root-knot nematode control strategies.

• Mycobiology
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• v.28 no.3
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• pp.115-118
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• 2000

To determine the degree of variability among the host plant species in their abilities to become colonized by arbuscular mycorrhizal fungi (AMF), the inoculum for AMF was collected from the various sites in Korea and was inoculated to the three horticultural plants; Tagetes patula, Torenia fournieri, and Salvia splendens. After 4-month growth under greenhouse, mycorrhizal root colonization rates and spore density were measured. The roots of T. patula showed higher colonization rate than both plants of T. fournieri and Salvia splendens. The mycorrhizal root colonization was influenced by both of the AM fungal inoculum and the host species or their interactions. The combination of the host and fungal species was suggested to be important for the application of AMF to horticultural crops.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.147-154
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• 1999

This paper presents a procedure for the frequency-domain analysis of a non-proportionally damped structure subjected to stationary seismic loads and for the finding of proper damper locations through simple analysis procedure without iteration. The shear areas of the dampers are decided in proportion to the magnitude of the components of the primary mode shape vector and to the root mean square values of the story drifts, The root-mean-squear responses are obtained using a power spectral density function for the ground acceleration. the results are compared with those obtained from damper placement decided in sequency based on the maximum story drift. According to the results the reliability of the proposed method turns out to be satisfactory compared to the methods which required iteration.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.317-320
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• 2015

Documenting work-in-progress on construction sites using images captured with smartphones, point-and-shoot cameras, and Unmanned Aerial Vehicles (UAVs) has gained significant popularity among practitioners. The spatial and temporal density of these large-scale site image collections and the availability of 4D Building Information Models (BIM) provide a unique opportunity to develop BIM-driven visual analytics that can quickly and easily detect and visualize construction progress deviations. Building on these emerging sources of information this paper presents a pipeline for model-driven visual analytics of construction progress. It particularly focuses on the following key steps: 1) capturing, transferring, and storing images; 2) BIM-driven analytics to identify performance deviations, and 3) visualizations that enable root-cause assessments on performance deviations. The information requirements, and the challenges and opportunities for improvements in data collection, plan preparations, progress deviation analysis particularly under limited visibility, and transforming identified deviations into performance metrics to enable root-cause assessments are discussed using several real world case studies.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.5
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• pp.77-87
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• 2018

Traffic Density is the most important of the three primary macroscopic traffic stream parameters, because it is most directly related to traffic demand(Traffic Engineering, 2004). It is defined as the number of existing vehicles within a given distance at a certain time. However, due to weather, road conditions, and cost issues, collecting density directly on the field is difficult. This makes studies of density less actively than those of traffic volume or velocity. For these reasons, there is insufficient attempts on divers collecting methods or researches on the accuracy of measured values. In this paper, we used the 'Density Measuring System' based on the synthesise technology of several camera images as a method to measure density. The collected density value by the 'Density Mesuring System' is selected as the true value based on the density define, and this value was compared with the density calculated by the traditional measurement methods. As a result of the comparison, the density value using the fundamental equation method is the closest to the true value as RMSE shows 1.8 to 2.5. In addition, we investigated some issues that can be overlooked easily such as the collecting interval to be considered on collecting density directly by calculating the moment density and the average density. Despite the actual traffic situation of the experiment site is LOS B, it is difficult to judge the real traffic situation because the moment density values per second are observed max 16.0 (veh/km) to min 2.0 (veh/km). However, the average density measured for 15 minutes at 30-second intervals was 8.3-7.9 (veh/km) and it indicates precisely LOS B.

• Korean journal of applied entomology
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• v.25 no.3 s.68
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• pp.183-189
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• 1986

Fifty three diseased root samples of Chinese cabbage and 22 soil samples were taken from six alpine areas in Kangwon province to examine the organisms causing root rot of Chinese cabbage. Among thirteen microorganisms detected from diseased roots samples, Pythium ultimum, Pythium echinocarpum and Rhizoctonia solani were detected frequently and were pathogenic to Chinese cabbage. Five to 100% of young Chinese cabbage plants grown in the sample soils taken from alpine cabbage fields were infected either alone or together with P. ultimum, P. echinocarpum and R. solani, depending upon the or gin of sample soils. When relative density of the three organsims in the sample soils was estimated based on the infection frequency on the plants grown in those sample soils, P. ultimum was prevalent only in Chahang-i-li area. P. echinocarpum was prevalent in Yongsan-il-li, Hoengwe-li, and Munmaek areas. R. solani was solely found in Maebongsan area where both P. ultimum and P. echinocarpum were not detected. In the three areas where both P. ultimum and P. echinocarpum were present, density of P. echinocarpum was generally greater than that of P. ultimum. Seedlings of thirty major Chinese cabbage varieties were inoculated independently with the three organisms in the greenhouse. Six varieties were resistant to P. ultimum. Three and two varieties were moderately resistant to P. ultimum and P. echinocarpum, respectively. All varieties were highly susceptible to R. solani.

• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.144-148
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• 2002

The overall objective of this study was to determine which variety of carrot-10 Japan varieties or 6 domestic varieties- produces the optimum quality, when cultivated on Jeju Island. Plant height, leaf number and leaf weight were observed to be more superior in the purebred variety ‘Jungang’than other varieties. further studies, however, skewed the crossing variety ‘Bureoun’was superior to all others. Furthermore, when comparing root diameter, root length and root weight, the ‘Bibary’was superior in both the purebred and crossing variety, When researching Japan varieties, the crossing variety, ‘Jung’showed an increase in underground root. The purebred variety ‘Donghae’also showed an increase in underground root. Marketable yields in domestic varieties were greatest in ‘Hapa’, while in Japan varieties, ‘Kaneko’was the most productive. The percentage of root cracked was 15％ greater in ‘Bureon’. In the purebred variety, Jungang, the percentage was only 10％. The percentage of roots branched was highest in ‘Hidomi’which showed a rate of 9%, The roots branched rate was 2% for ‘Jung’and 6％ for‘Donghae’. Considering the percentage of roots clacked or branched, the marketability of carrots was higher in Japan varieties in comparison with domestic varieties. Therefore we conclude that, in the cropping patterns of carrots, the domestic variety has an advantage over the Japan variety.

• Korean Journal of Medicinal Crop Science
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• v.5 no.1
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• pp.67-71
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• 1997

Bupleurum falcatum is one of the oldest medicinal crop spontaneously generated as well as cultivated by man and successfully grown during the summer season in Korea. This study was conducted to examine the effect of planting density in the row spacing and hill spacing system using machine seeder on major agronomic traits, yield and labor saving. In 1993 and 1994, a spilt plot design was used with row spacing as the main plot and hill spacing as subplot. Labor saving efficency of the machine seeder reduced 96% than the hand seeding in sowing time required. Number of seeding stand increased, but stem height and number of nodes did not affect with different density in each row and hill spacing. There were reduced with narrow hill spacing on stem diameter, number of branches, shoot weight and root traits. There was no significant interaction between row and hill spacing for any major traits studied except shoot weight. Yield was more increase at 20cm than at 30cm row spacing. For these studies the optiomum density appears to be between drilling or 5cm hill spacing with 20cm row spacing. A highly significant positive correlation was appeared between number of seedling stand and root yield.

• Weed & Turfgrass Science
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• v.5 no.1
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• pp.29-34
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• 2016

Large patch disease in Zoysia japonica Steud. is the most destructive disease in turfgrass. For large patch management, it has been dependent on chemical controls but pesticides are harmful to soil, water and biodiversity. In this study, we evaluated 4 Streptomyces spp. strains (S2, S5, S8 and S12) which were selected in previous studies using metagenome approaches. Root colonization of the strains, large patch suppressing effect and the pathogen density change in actual golf course were investigated to evaluate biological control potential of the strains. All strains exhibited reliable root colonization ability that strains populations were higher than $6log\;cfu\;g^{-1}$ in turfgrass rhizosphere. The pathogen density, with S8 treatment, was detected average of 0.7 after a week and average of 1.2 after 4 weeks. Disease control and suppressive the pathogen population by S8 strain showed higher efficiency than other strains. S8 was applied in an actual golf course for the large patch control and pathogen density. The pathogen density in S8 treatment plot was detected below 1.6 per toothpick and lower compared with untreated plot. The results indicated that pathogen density was suppressed by S8 and the stain has great potential as a biological control agent for the large patch.

• Korean Journal of Korean Medical Institute of Dermatology and Aesthetics
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• v.1 no.1
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• pp.127-144
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• 2005

This study compared the activity of the aerial part of P. japonicum with its root in order to examine the possibility of the medicinal use of the aerial part, which has not been used as medicine, in substitute for the root that has traditionally been used as medicine. For this purpose, the author measured the proliferation of Human $CD4^-$ T cells, which are related to immunity, the differentiation of HL-60 cells, and the contents of IL-6, IgE and $TNF-{\alpha}$ and compared their anti-cancer effect on Hep3B and A549 cells. The results of this study are as follows: 1. As for Human $CD4^-$ T cells, $1.0\;g/{\ell}$ methanol extract from the aerial part promoted the proliferation of the cells 1.8 times higher while $1.0\;g/{\ell}$ methanol extract from the root did by 1.76 times higher compared to the control group. 2. As for HL-60 cells, methanol extract and water extract from the aerial part showed differentiation 1.14 times higher and 1.12 times higher respectively while methanol extract and water extract from the root did 1.14 times higher and 1.07 times higher compared to tile control group. 3. Cell density was highest on Day 4 of culture in all samples, Methanol extracts from the aerial part and the root showed activities of $7.9{\times}10^3\;cells/m{\ell}$ and $7.5{\times}10^3\;cells/m{\ell}$ respectively, and water extracts from the aerial part and the root did activities of $5.3{\times}10^3\;cells/m{\ell}$ and $6.1{\times}10^3\;cells/m{\ell}$. 4. The secretion of IL-6 was highest on Day 4 of culture. Methanol extracts from the aerial part and the root showed secretions of $6.7{\times}10^{-3}\;pg/cells/m{\ell}$ and $7.2{\times}10^{-3}\;pg/cells/m{\ell}$ respectively, and water extracts from the aerial part and the root did secretions of as high as $7.0{\times}10^{-3}\;pg/cells/m{\ell}$ and $6.0{\times}10^{-3}\;pg/cells/m{\ell}$. 5. As for the production of IgE, water extract from the root effectively inhibited the product at $1,000\;{\mu}g/m{\ell}$, methanol extract from the root at $10\;{\mu}g/m{\ell}$ and $100\;{\mu}g/m{\ell}$, water extract from the aerial at $1,000\;{\mu}g/m{\ell}$, and methanol extract from the aerial part at $1,000\;{\mu}g/m{\ell}$. 6. According to the result of measuring the content of $TNF-{\alpha}$, methanol extracts from the root and the aerial part showed inhibition effect at $10\;{\mu}g/m{\ell}$, $100\;{\mu}g/m{\ell}$ and $1,000\;{\mu}g/m{\ell}$. 7. As for liver cancer cell Hep3B, $1.0\;g/{\ell}$ methanol extracts from the root and the aerial part showed inhibition effects of 78% and 70% respectively, and $1.0\;g/{\ell}$ water extracts from the root and the aerial part did inhibition effects of 56% and 59%. 8. As for lung cancer cell A549, $1.0\;g/{\ell}$ methanol extracts from the root and the aerial part showed inhibition effects of 75% and 70% respectively, and $1.0\;g/{\ell}$ water extracts from the root and the aerial part did inhibition effects of 48% and 45%. The results of this study presented above show that the aerial part of P. japonicum has immunizing and anti-cancer effects as high as its root, which has commonly been used as medicine. There should be more in-depth research on the aerial part of P. japonicum in the future.