• The Korean Journal of Mycology
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• v.29 no.1
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• pp.72-74
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• 2001

A destructive collar rot of water cress (Oenanthe javanicav) occurred in the commerical farm at Karye-myon, Uiryong-gun, Kyongsangnam-do in 2000. The causal fungus caused stem rot, crown rot, wilt or blight of water cress and the disease incidence in 3 fields ranged from 28.6 to 42.8%. White mycelia spread over tissues near the soil surface or stems, and sclerotia developed on the lesions at late season. The fungus grew well on PDA at $20^{\circ}C$ and the typical clamp connection was formed on its tough white mycelia $4.1{\sim}10.3{\mu}m$. The fungus also formed white mycelia mats and sclerotia at $20^{\circ}C$ on PDA. The sclerotia were globoid and sized $1.0{\sim}6.3{\times}1.0{\sim}5.2mm$ (av. $2.4{\sim}2.2mm$). The causal fungus of collar rot disease was identified as Sclerotium rolfsii on the basis of mycological characteristics and pathogenicity test, This is the first report on the collar rot of water cress caused by Sclerotium rolfsii in Korea.

• The Korean Journal of Mycology
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• v.32 no.1
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• pp.54-56
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• 2004

Rust disease was occurred on blackberry lily (Belamcanda chinensis) in several farmer's fields located in Heohwa-myon, Goseong-gun, Gyeongnam province in Korea. The typical symptoms of the disease appeared as small, yellowish spot on leaves at first. The spots then turned brown, their edges rised slightly, and powdery mass of yellow or yellowish green spores appeared on the lesions. Severely infected leaves were blighted and eventually died. Urediniospores were yellow or yellowish brown in color, globoid to ovoid in shape and $21{\sim}46{\times}18{\sim}38\;{\mu}m$ in size. Teliospores were brown in color, oblong or clavate in shape and $32{\sim}64{\times}12{\sim}26\;{\mu}m$ in size. The causal fungus was identified as Puccinia belamcandae based on morphological characteristics and host specificity. This is the first report on the rust of B. chinensis caused by P. belamcandae in Korea.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.26-34
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• 2008

This study focus on segmentation process that classifies road surfaces into 5 different categories, dry, wet water, icy, and snowy surfaces by analyzing asphalt-paved road images taken in daylight. By using the polarization coefficients, the proportions of horizontally polarized components to vertically polarized components, regions with over 1.3 polarization coefficients are classified as wet surfaces. Except for wet surfaces, the decision process a lies time-frequency analysis to other parts by using the third order wavelet packet transform. In addition, by using the average frequency characteristics of dry and icy surfaces from image templates, decide which is closer to a test image, and finally identify dry and icy surfaces. It is confirmed that the reposed estimation and segmentation of recognition on various images. This can be interpreted as an indication that image-only mad surface condition supervision is probable.

• Radiation Oncology Journal
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• v.6 no.2
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• pp.263-268
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• 1988

This paper presents dose distributions in water around Fletcher-Suit colpostat containing $^{137}Cs$ tube, and shielding effect of Internal lead shield. Using ready packed film, author measured dose distribution in water around the colpostat containing cesium source. Nine sheets of films on one side of the colpostat are packed with acryl frames cut out so as to fill water, and irradiated in water by cesium source in the colpostat. Dose distributions on transverse plane and upper plane 0.5cm from upper surface of the colpostat were measured. Shielding effect was greater in upper medial direction than in lower medial direction. And that was the greatest around $30^{\circ}$ from the axis of the colpostat on upper side and around $50^{\circ}$on lower side. In the region 7cm from the center of the colpostat, shielding efficiency was 0.23 to 0.35 on the lower $50^{\circ}$ and 0.26 to 0.42 on the upper $30^{\circ}$, and decreased with increase of distance.

• Research in Plant Disease
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• v.21 no.4
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• pp.268-272
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• 2015

Bacterial leaf blight caused by Pseudomonas syringae pv. porri is one of the major bacterial diseases of garlic (Allium sativum). In South Korea, the disease has only been observed in garlic-growing regions of Jeju island. The spatial distribution pattern of the disease was analyzed by binary power law, in which the natural logarithm of the observed variance is regressed on the natural logarithm of the binomial variance. The estimated slope (b=1.361) of the regression was greater than 1 which meant that the diseased plants were aggregated. The sequential sampling plans were developed for estimating the mean incidence rate ($p_m$) and classifying the mean incidence as being below or above the critical incidence rate ($p_t$). These results could be used on more efficient and higher precisive sampling for bacterial blight of garlic compared to fixed sample sized sampling.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.3
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• pp.133-139
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• 1979

In order to evaluate the effect of developed Nk compound fertilizers, 17-0-17 granular and powder, and 17-0-14 granules in comparison with single fertilizers, urea and potassium on rice (Oryzae sativa) ; cultivar, Milyang 23, (Orizae Sativa), a field experiment was carried out. Results obtained are as follows : 1. The top dressing of NK compound fertilizers tended to produce higher paddy yield than that of single fertilizers; urea and patasstum muriate. 2. The absorption of potassium and nitrogen by rice plant from the plot of NK granular compound fertilizer, 17-0-17, was greater than from the plots the absorption of those elements received other types of ferilizers and application method The absorded K/Ca+Mg ratio in milli equivalent basis in plant was also appeared to be in same order as the absorption of nitrogen and potassium. 3. From the results of present study it seemed necessary to evaluate the NK compound fertilizer for the top dressing at effective tillering stage of rice as well.

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.2
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• pp.53-57
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• 1972

In order to obtain some informations on the improvement of fertility of poor red yellow soils widely distributed in hilly lands of Korean peninsula, a pot culture study was made with a hill land soil in comparison with a fertile soil commonly used for vegetables. The results are as follows; 1. In addition to the normal application of phosphate, the mixing of a large dose of fused phosphate with whole soil increased the yeild of chinese cabbage remarkably, having the promotion particulary of the available phosphate level in the acidic low fertility soil. At the sometime the mixing seemed to short down the period of soil maturing to fertile for good crop. It is, however, considered that such effect of fused phosphate must also be evaluated economically through a long term experiment. 2. A relatively close relationship between the soil phosphate soluble in dilute acid and chinese cabbage growth was observed.

• Korean Journal of Medicinal Crop Science
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• v.7 no.2
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• pp.89-93
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• 1999

This study was carried out to investigate the effects of planting density, time and frequency of pinching on growth and yield of Lycium chinese Miller cultivated in vinyl house. This experiment was conducted at the experimental field of Cheong-yang Agriculture High School, Cheong-yang, Chung-nam province, in 1997 to 1998. The number of flowers, fruit setting number and dry weight of fruits per branch were increased as the spacings were wider, but the fruit yield per unit area was decreased up to the narrowest spacing plot of $60\;{\times}\;20cm$. The good results of growth status and fruit yield was obtained at the early pinching in May 5. As the more frequent pinching were treated, the more number of flowers and fruits per branch were produced, showing increase of fresh and dry yield, because of much more branches per plot.

• Korean Journal of Construction Engineering and Management
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• v.6 no.4 s.26
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• pp.172-180
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• 2005

The purpose of this study is to suggest a new SRC(Steel Ready mixed Concrete) lining board. The research method of this study includes problem analysis of existing lining boards a constant load test and a fatigue test. The results of this study are as follow : 1) the suggested new lining board improves the function and reduce slipperiness than existing lining boards. 2) the strength of the new SRC lining board is analyzed as superior than existing lining boards from the results of constant load test and fatigue test.

• Research in Plant Disease
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• v.17 no.2
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• pp.225-227
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• 2011

The stem rot of Chrysanthemum zawadskii var. latilobum occurred in the landscape field of Sanggwan-myeon, Wanju-gun, Jeonbuk, Korea in September 2009. The typical symptoms of the disease were water-soaking and dark brown rot on the stem, wilting and blighting. Most infected plants died of the disease. White mycelial mats were spread over lesions and brown sclerotia were formed on stems and near soil surface. The sclerotia were spherical or irregular, 0.8-3.5 (mean 1.8) mm in size on potato dextrose agar, brown in color. The optimal temperature range of hyphal growth was $25-30^{\circ}C$ and the hyphal diameter was 4-9 ${\mu}m$. Clamp connections were observed in the hyphae of the fungus grown on potato dextrose agar. Pathogenicity of the casual organism was provided on C. zawadskii according to Koch's postulate. The fungus was identified as Sclerotium rolfsii on the basis of mycologiclal characteristics and pathogenicity test to host plants. This is the first report on the stem rot of C. zawadskii caused by S. rolfsii in Korea.