• Journal of Ecology and Environment
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• v.42 no.4
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• pp.227-239
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• 2018

Background: Predicting the potential habitat of plants in arid regions, especially for medicinal ones, is very important. Although Pergularia tomentosa is a key species for medicinal purposes, it appears in very low density in the arid rangelands of Iran, needing an urgent ecological attention. In this study, we modeled and predicted the potential habitat of P. tomentosa using maximum entropy, and the effects of environmental factors (geology, geomorphology, altitude, and soil properties) on some characteristics of the species were determined. Results: The results showed that P. tomentosa was absent in igneous formation while it appeared in conglomerate formation. In addition, among geomorphological units, the best quantitative characteristics of P. tomentosa was belonged to the conglomerate formation-small hill area (plant aerial parts = 57.63 and root length = 30.68 cm) with the highest electrical conductivity, silt, and $CaCO_3$ content. Conversely, the species was not found in the mountainous area with igneous formation. Moreover, plant density, length of roots, and aerial parts of the species were negatively correlated with soil sand, while positive correlation was observed with $CaCO_3$, EC, potassium, and silt content. The maximum entropy was found to be a reliable method (ROC = 0.91) for predicting suitable habitats for P. tomentosa. Conclusion: These results suggest that in evaluating the plant's habitat suitability in arid regions, contrary to the importance of the topography, some environmental variables such as geomorphology and geology can play the main role in rangeland plants' habitat suitability.

• The Plant Pathology Journal
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• v.16 no.6
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• pp.312-317
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• 2000

The selected five plant growth-promoting rhizobacteria (PGPR) strains, WR8-3 (Pseudomonas fluorescens), WR8-6 (P. putida), WR9-9 (P. fluorescens), WR9-11 (Pseudomonas sp.), and WR9-16 (P. putida) isolated in the rhizosphere of watermelon plants were tested on their growth promotion and control effect against gummy stem rot of watermelon. Strains, WR8-3 and WR9-16 significantly increased stem length of watermelon, and there was a little increase in leaf area, fresh weight and root length when strains, WR8-3, WR9-9 and WR9-16 were treated. Generally, seed treatment was better for plant growth promotion than the soil drench, but there was no significant difference. Seed treatment and soil drench of each bacterial strain also significantly reduced the mean lesion area (MLA) by gummy stem rot, but there was no significant difference between the two treatments. At initial inoculum densities of each strain ranging from 10$^6\;to\;10^{15}$ cfu/g seed, approximately the same level of disease resistance was induced. But resistance induction was not induced at the initial inoculum density of 10$^3$ cfu/g seed. Resistance was induced by treating the strains, WR9-9, WR9-11 and WR9-16, on all of four watermelon varieties tested, and there was no significant difference in the decrease of gummy stem rot among varieties. Populations of the strains treated initially at log 9-10 cfu/g seed, followed with a rapid decrease from planting day to 1 week after planting, but the population density was maintained above log 5.0 cfu/g soil until 4 weeks after planting. Generally no or very weak in vitro antagonism was observed at the strains treated excepting WR9-11. Rifampicin-resistant bacteria which had been inoculated were not detected in the stems or leaves, which suggesting that the bacterium and the pathogens remained spatially separated during the experiment. This is the first report of rsistance induction in watermelon to gummy stem rot by PGPR strains.

• Korean Journal of Acupuncture
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• v.28 no.3
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• pp.53-62
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• 2011

Objectives : Burn is most common adverse events of moxibustion. Various kinds of components influence on the heat stimulation of commercial indirect moxa, but there are not enough investigation about the status. The purpose of this study is to investigate the 6 components to build a base data that is currently available to build a standard of an indirect moxibustion. Methods : The length and weight, density, thickness of the paper disk, diameter of the paper disk, and diameter in the paper disk hole were measured against 6 kinds of commercial indirect cautery. Results : 1. 'Seoam', 'Kihwang' and 'Taegeuk' shows uniform length than the other brands. 2. 'Dongbang', 'Kihwang' and 'Taegeuk' shows uniform weight than the other brands. 3. 'Dongbang', 'Kihwang' and 'Taegeuk' shows uniform density than the other brands. 4. 'Dongbang' and 'Kihwang' shows uniform thickness than the other brands. 5. 'Seoam', 'Dongbang' and 'Taegeuk' shows uniform diameter of disc hole than the other brands. Conclusions : As a result of investigation, 'Dongbang' and 'Kiwhang' indirect moxibustion was identified as a uniform product. This results are considered as an important base materials of the KS through commercial indirect moxibustion.

• Journal of the Korean Wood Science and Technology
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• v.29 no.2
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• pp.69-75
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• 2001

This study was carried out to investigate the properties of woodceramics made from thinned logs of Cryptomeria japonica. In order to find the effect of steam injection time on the woodceramics fabricated with boards, boards were made with the non-steamed treatment and steamed treatment 1, 5, 10 min. at $250^{\circ}C$. The percentage of weight loss was proportional to the increased density of board The reducing rate of length and thickness, however, decreased with increasing density of board. The rate of weight loss, length and thickness reduction in non-steamed board were slightly higher than those of steamed board. When the resin impregnation rate increased, the bending strength and compressive strength of woodceramics had a tendency to increase. The bending strength and compressive strength of woodceramics in non-steamed board was higher than those of steamed board. But there was little difference between dimensional and strength properties of woodceramics and steam injection time of board.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.4
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• pp.259-273
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• 2021

We conducted a study to investigate the characteristics of the carbon cycle of two streams (located in Shig a Prefecture, Japan), having similar size, namely, the Adokawa stream (length: 52 km, area: 305 km², watershed population: 8,000) and the Yasukawa stream (length: 62 km, area: 380 km², watershed population: 120,000), but with different degree of human activity. Samples were collected from these two streams at 14 (Adokawa stream) and 23 (Yasukawa stream) stations in the flowing direction. The dissolved inorganic carbon (DIC) concentration and the stable carbon isotope ratio of DIC (δ¹³C-DIC) were measured in addition to the watershed features and the chemical variables of the stream water. The δ¹³C-DIC (-9.50 ± 2.54‰), DIC concentration (249 ± 76 µM), and electric conductivity (52 ± 13 µS/cm) in Adokawa stream showed small variations from upstream to downstream. However, the δ¹³C-DIC (-8.68 ± 2.3‰) upstream of Yasukawa stream was similar to that of Adokawa stream and decreased downstream (-12.13 ± 0.43‰). DIC concentration (upstream: 272 ± 89 µM, downstream: 690 ± 37 µM) and electric conductivity (upstream: 69 ± 17 µS/cm, downstream: 193 ± 37 µS/cm) were higher downstream than upstream of Yasukawa stream. The DIC concentration of Yasukawa stream was significantly correlated with watershed environmental variables, such as, watershed population density (r = 0.8581, p<0.0001, n = 23), and forest area percentage of the watershed (r = -0.9188, p<0.0001, n = 23). δ¹³C-DIC showed significant negative correlation with the DIC concentration (r = -0.7734, p<0.0001, n = 23), electric conductivity (r = -0.5396, p = 0.0079, n = 23), and watershed population density (r = -0.6836, p = 0.0003, n = 23). Our approach using a stable carbon isotope ratio suggests that DIC concentration and δ¹³C-DIC could be used as indicators for monitoring the health of stream ecosystems with different watershed characteristics.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.1
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• pp.91-99
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• 2007

The research was carried out to define the morphological and growth characteristics of Poa pratensis L. (Kentucky bluegrass) 'Pureundul' native to Korea. Poa pratensis 'Pureundul' was collected from the belt highway around Mt. Uam located in Naedeok-dong, Cheongju City, Chungcheongbuk-do Province on May 5, 1995. The morphological characteristics of 'Pureundul' were compared with those of 205 individuals of native Poa pratensis collected throughout the nation from June 11, 2000 to June 21, 2003. The findings were as follows : The height of plant was 28.2cm but increased to 40.0cm at the flowering time. The height of first node from the base was 6.8cm and the length and width of leaf were 17.3cm and 2.9mm, respectively. The length of a spike was 7.9cm. Based on these morphological characteristics, 'Pureundul' was defined medium type Kentucky bluegrass. Visual quality(1~9), visual color and visual density were measured. The visual quality, color and density of 'Pureundul' were not superior to those of introduced species but above the average other native species. The damages from the diseases during summer resulted in poorer visual quality of color of 'Pureundul'. But the spread of the diseases was slower in 'Pureundul' than other native species, and accordingly 'Pureundul' didn't suffer from more quality deterioration from July to September during which the diseases broke out. Entering fall, 'Pureundul' showed high quality comparable to that of the introduced species. If 'Pureundul' is put to breeding by implementing pest control in summer and introducing disease tolerant genes, it will be used to make greens of greater quality than now.

• Journal of the Korean Society of Costume
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• v.56 no.8 s.108
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• pp.74-82
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• 2006

In ancient China, Su(綬) was the ornament of the full dress. It had originated from tying the jade or another thing before Jen(秦:Qin) dynasty and it tied the imperial jade seal and the chop from Han dynasty. Su of Han dynasty was different in the inscape, colour, length and density according to the grade. And the shape was the straight line. But these phenomena were changed after Han dynasty. This study showed how it changed. To studying used the comparison method of literature records, paintings and archeological relics. It mostly studied imperial Su. Su of Han dynasty of the high grade was formed by Yeok, the circle type jade and Su(Su moaned whole Su, at the same time moaned the part of Su, too). Afterward, Yeok was changed into Small Su[小綬] and Su was changed into Big Su(大綬). Originally the circle type jade was connecting Yeok to Su, but it was changed into tying Small Su only. Su of Han dynasty used the four kinds of colour, but from Su(隋: Sui) dynasty used the six kinds of colour. Originally Su was interlacing, but it was changed into the silk fabric from Song[宋] dynasty. According to using silk fabric's Su, it was likely to disappear the system distinguishing the grade by length. And it kept the method of interlacing the reticulation in the low part of silk fabric's Su. So, after using silk fabric's Su, the system of the density was not about the main body but about the reticulation. Su was been used woven with supplementary golden wefts, too. The circle type jade was chiseled the dragon and cloud from Geum[金:Jin] dynasty. These not the pattern of silk fabrics.

• Fire Science and Engineering
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• v.24 no.6
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• pp.170-175
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• 2010

The effect of carbon dioxide addition on soot formation was investigated in jet diffusion flames in coflow. Flame temperature were measured with R-type thermocouple and the boundary temperature between blue and yellow flame was confirmed. Light-extinction method was introduced for the relative soot density (1-I/$I_0$) in the in-flame region. He-Ne laser with wave length at 632.8 nm was used for the light source, and the signal attenuated by absorption and scattering was detected directly. Oxidizer velocity effect on soot formation was studied to know that the thermal influence for soot formation. The results showed that the temperature of both blue and yellow flame were decreased according to the dilution of carbon dioxide but boundary temperature was nearly constant. The relative soot density was lower when carbon dioxide was added in oxidizer stream and oxidizer velocity increased. These were caused by the reduction of flame temperature and shorter residence time for soot growth. Also carbon dioxide addition enhanced the instability of jet flames like flickering, so the flame length was a little longer than pure ethylene/air flame.

• Transactions of the Society of Information Storage Systems
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• v.1 no.2
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• pp.150-154
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• 2005

The effects of track format on the inter-track crosstalk of holographic ROM system are investigated. To quantify the effect of inter-track crosstalk for various track width and pitch, we defined Signal to Crosstalk noise Ratio(SCR) as a criterion. A numerical simulation is used to obtain the SCR as a function of track widths and pitches. We compared different 4 track widths having 0.3, 0.4, 0.5, and 0.6 ${\mu}m$ considering resolving power of lens and recording density. The simulation results show that the SCRs for each track width are maximized at the track pitch which has the value of 0.72, 0.72, 0.74, and 0.5 ${\mu}m$ respectively. Next, for the three sets with track width-pitch(0.4-0.72, 0.5-0.74, 0.6-0.8 ${\mu}m$) which showed the maximum SCR, we set a minimum pit length so that all sets have a DVD equivalent data density and compared RF signals passed from the slit. The simulation results show that when the track width, pitch, and minimum pit length have 0.5, 0.74, and 0.4 ${\mu}m$ respectively, the difference between the maximum and minimum value of the RF signal showed the greatest value. Also, we investigated RF signal in case of using an amplitude inversion mask, which transmitted regions are inversed against the conventional mask. The simulation results show that the better RF signal may be obtained by using an amplitude inversion mask.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.293-299
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• 2009

In manufacturing the crack-free carbonized boards using fiberboards, shrinking ratio, weight loss and density variation of carbonized boards at each carbonization temperature were investigated. Fiberboards with thickness of 3, 4.5, 6, and 18 mm were carbonized while pressed with pressure plates at different temperature from $400^{\circ}C$ to $1,000^{\circ}C$ using a ordinary laboratory furnace. Either of crack or twist was not observed in fiberboards by adapting the pressing carbonization method. The ratios of shrinkage of length, width, and thickness were 10~25%, 12~25%, and 28~48%, respectively, and shrinkage ratio of thickness was higher than those of length and width with increasing the carbonization temperature. Weight loss tended to increase with increasing the carbonization temperature, but low correlation between weight loss in thickness of fiberboards and carbonization temperature was observed. Density of 3 mm carbonized hardboard had the highest value and it tended to increase with increasing the carbonization temperature.