• Applied Microscopy
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• v.20 no.1
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• pp.120-127
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• 1990

The zoospores of Polymyxa graminis known as vector of barley yellow mosaic virus(BYMV) were found from the rootlets of diseased barley plants. The X-bodies in the lower epidermis of diseased leaf tissues were reddish under fluorescence microscopy. The shape of virus particles was flexuous rod and 300-1,000 nm in length. The pinwheel structures, cylindrical inclusion bodies, ring-form inclusion bodies, and crystalline lattice-like structure were found together with virus particles in the cytoplasm of diseased leaf tissues. Generally, intracellular organelles in the diseased barley leaf tissues infected with BYMV were either not well-developed or degenerated.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.1
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• pp.20-32
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• 1995

Springs for vehicle suspension control the vibration of a car and influence on the ridability, safety, and life of a car. In the paper, the computer aided design program has been developed, which design the leaf spring shape from the given specifications using basic theory and the expert's knowledge, and the design results are checked by the analysis theory in order to increase the accuracy, and feed back to the design input. For the purpose of easy use, this program consists of pull-down menu and interactive input mode. To prove the effectiveness of this program. two springs, of which one is symmetric, other asymmetric, are designed and analyzed, and the outputs are compared to the experiments. Considering the tolerance of the given specifications, the results are good.

• Korean Journal of Medicinal Crop Science
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• v.14 no.6
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• pp.342-346
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• 2006

Anatomical characters of the Bupleurum latissimum Nakai, an endemic species of Korea, were investigated to confirm its phylogenetic relationships. Compare to other species with anatomical characters, B. latissimum is very similar with B, euphorbioides and B, longeradiatum in point of lacking of pith in the stem, shape of involucres, number of vascular bundles in radical leaf and cauline leaf, and lacking stomata in adaxial leaf surface. The other hand, protruded pollen aperture character appears in B. latissimum and B. euphorbioides. On the based of anatomical characters, therefore, B. latissimum has closest relationships with B. euphorbioides and B. longeradiatum. It also needs molecular study including Asian species in order to confirm phylogenetic position and speciation process apparently.

• Journal of Biosystems Engineering
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• v.21 no.3
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• pp.315-324
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• 1996

This study was one of a series of studies on application of machine vision and image processing to extract the geometrical features of plants and to analyze plant growth. Several algorithms were developed to measure morphological properties of plants and describing the growth development of in-situ lettuce(Lactuca sativa L.). Canopy, centroid, leaf density and fractal dimension of plant were measured from a top viewed binary image. It was capable of identifying plants by a thinning top viewed image. Overlapping the thinning side viewed image with a side viewed binary image of plant was very effective to auto-detect meaningful nodes associated with canopy components such as stem, branch, petiole and leaf. And, plant height, stem diameter, number and angle of branches, and internode length and so on were analyzed by using meaningful nodes extracted from overlapped side viewed images. Canopy, leaf density and fractal dimension showed high relation with fresh weight or growth pattern of in-situ lettuces. It was concluded that machine vision system and image processing techniques are very useful in extracting geometrical features and monitoring plant growth, although interactive methods, for some applications, were required.

• Korean Journal Plant Pathology
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• v.10 no.4
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• pp.336-338
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• 1994

In 1991, the leaf brown spot of ivy-aureus (Scindapsus aureus) was found in Taejon and Seoul, Korea. The symptoms were appeared as dark-brown spots. The lesions were often surrounded by yellowish halos. These spots were enlarged to circular or elliptical in shape and dark-brown to black in color with slightly elevated in margin and sunken in center. The pathogenic bacteria were isolated from the diseased leaf of ivy-aureus were identified as Erwinia chrysanthemi on the basis of bacterial characteristics therefore, we would like to propose to the name of ivy-aureus disease caused by E. chrysanthemi as“bacterial brown rot of ivy-aureus”hereafter.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.4
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• pp.343-349
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• 2015

This is a study for the improvement of the fractured lug structure that connects the landing gear to the fuselage of the aircraft using the composite leaf spring landing gear. The lug surface was analyzed to find out the cause of fracture. The lug was destroyed by the crack initiation and propagation under the repeated stresses. The frictional wears of the lug structure were proceeded and that affected adversely to the crack. Also, the square protrusion of the lug has a weak shape to bring about stress concentration. The design changes were conducted and the test was performed to verify changed design results.

• Journal of Bio-Environment Control
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• v.28 no.1
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• pp.1-8
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• 2019

The study aimed to determine effects of light emitting diode (LED) and the ultraviolet radiation (UVA) light of plant factory on plant growth and ascorbic acid content of spinach (Spinacia oleracea cv. Shusiro). Plants were grown in a NFT (Nutrient Film Technique) system for 28 days after transplanting with fluorescent light (FL, control), LEDs and UVA (Blue+UVA (BUV), Red and Blue (R:B(2:1)) + UVA (RBUV), Red+UVA (RUV), White LED (W), Red and Blue (R:B(2:1)), Blue (B), Red (R)) under the same light intensity ($130{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and photoperiod (16/8h = day/night). All the light sources containing the R (R, RB, RUV, and RBUV) showed leaf epinasty symptom at 21 days after transplanting (DAT). Under the RUV treatment, the lengths of leaf and leaf petiole were significantly reduced and the leaf width was increased, lowering the leaf shape index, compared to the R treatment. Under the BUV, however, the lengths of leaf and leaf petiole were increased significantly, and the leaf number was increased compared to B. Under the RBUV treatment, the leaf length was significantly shorter than other treatments, while no significant difference between the RBUV and RB for the fresh and dry weights and leaf area. Dry weights at 28 days after transplanting were significantly higher in the R, RUV and BUV treatments than those in the W and FL. The leaf area was significantly higher under the BUV treatment. The ascorbic acid content of the 28 day-old spinach under the B was significantly higher, followed by the BUV, and significantly lower in FL and R. All the integrated data suggest that the BUV light seems to be the most suitable for growth and quality of hydroponically grown spinach in a plant factory.

• Journal of the Korean Society of Tobacco Science
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• v.3 no.1
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• pp.58-65
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• 1981

This study was carried out to investigate the influence of distance of planting holes (51, 45, and 40 cm) and number of plants per a hole(4, 5, 6 plants) on agronomic characteristics, yield, and quality of an aromatic tobacco, Sohyang. The results are as follows: 1. Relative light intensity increased by widening the distance of holes. 2. Leaf area per a plant or per a leaf, and leaf length and width increased by widening the distance of holes and decreased by increasing the number of plants per a hole. But L. A. 1. increased by increasing the number of plants per a hole. Leaf shape index (Leaf length/Leaf width) showed little differences among treatments. 3. Dry weight of leaf, root, and stem per a plant decreased by increasing the number of plants per a hole. 4. Total nitrogen decreased by increasing number of plants per a hole and in the case of narrow distance of holes, but nicotine, reducing sugar, ether-extract and ash showed little differences. 5. Yield per 10a decreased by widening the distance of holes. 6. Quality(price per kg) was improved by increasing the number of plants per a hole at the Plot of 51m distance of holes. But there was no variation at the Plot of 45cm. And quality was decreased at the plot of 40cm distance of holes by increasing the number of Plants per a hole. 7. Price per 10a was highest in the plot of which plant spacing was $90\times$40cm and the number of plants per a hole was 4 (11112 plant/10a).

• Journal of Korean Society of Rural Planning
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• v.23 no.3
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• pp.53-60
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• 2017

In order to export Korean spray roses to the China, it is needed to analyse chinese preferences, rose attributes, and purchase intentions. The purpose of this study is to present the implications on the production and distribution of roses for export by analyzing the quality preference attributes and purchase intention of Korean rose for Chinese flower experts. A survey on the preference and purchase intention of Korean flower roses by Chinese flower experts was conducted through face - to - face interviews with flower show participants in China. Approximately 100 Chinese flower experts who participated in the Flower Show in 2016 received the questionnaire, and 86 survey results could be used for analysis. Survey data were analyzed using ordered probit and bivariate probit models. As a result of an analysis, it was found that Chinese flower experts were more likely to buy Korean roses than Chinese roses even if they consider flower color, leaf shape and size and color diversity. The probability of purchasing more than twice the price was higher than that of the color diversity considering the flower shape, leaf shape and size, but the bivariate order probit model was larger than that of flowers, leaves and size, and the order of probability size was changed. In order to increase the export of Korean spray roses to the Chinese market, We need to increase Chinese experts' preferences and satisfaction. For this purpose, it is very important to develop export varieties of roses with large flower buds and shape / coloring, and to apply the useful post-harvest technology that can extend freshness and distribution period of export roses.

• The Plant Pathology Journal
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• v.21 no.2
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• pp.164-166
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• 2005

Corynespora leaf spot occurred severely on balsam pear (Momordica charantia) at Changwon, Gyeongnam province in Korea in November and December 2003. The causal fungus isolated from infected leaves of the plants grew well on potato dextrose agar showing gray to brown color. Solitary or catenary conidia of the fungus were obclavate to cylindrical in shape, and pale olivaceous brown or brown in color. The number of isthmus pseudosepta ranged from 4 to 20 and measured 36~186${\times}$8~19 ${\mu}m$ in size. Conidiophores were pale to light brown in color and measured 94~648${\times}$3~8 ${\mu}m$ in size. Optimal temperature for mycelial growth was $30{\circ}C$. On the basis of mycological characteristics and pathogenicity, the fungus was identified as Corynespora cassiicola (Berk. & Curt.) Wei. This is the first report on the corynespora leaf spot of M. charantia caused by C. cassiicola in Korea.