• 한국연초학회지
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• 제9권1호
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• pp.45-55
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• 1987

For some basic information in tobacco breeding, the modes of inheritance and heritabilities for the twelve agronomic and chemical characters were estimated in the study of eight varieties partial diallel set. Additive gene actions were significant for all characters except total nitrogen content and dominance gene effects were also significant for all characters. Yield, number of leaves per plant, leaf length and leaf shape index were inherited as partial dominance, and overdominance was detected for plant height, stem diameter, internode length, total alkaloid, total nitrogen and total sugar content. Dominant gene showed increasing effects in yield, plant height, stem diameter, internode length, leaf width and total sugar content, but showed decreasing effects in the other characters. The broad heritability was very high for all characters. and the narrow heritability was high in days to flower and yield, but low in internode length, total alkaloid, total nitrogen and total sugar content.

• Applied Microscopy
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• 제20권1호
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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.

• 한국자동차공학회논문집
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• 제3권1호
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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.

• 한국약용작물학회지
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• 제14권6호
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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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• 제21권3호
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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.

• 한국식물병리학회지
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• 제10권4호
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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.

• 한국군사과학기술학회지
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• 제18권4호
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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.

• 생물환경조절학회지
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• 제28권1호
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• pp.1-8
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• 2019

본 연구는 식물공장시스템의 발광다이오드와 UVA 광원에서 자란 시금치 생육 및 아스코르브산 함량을 구명하고자 하였다. 시금치 '수시로' 품종은 정식 후 28일간 NFT 수경시스템에서 형광등(FL)을 대조구로 하여 적색광(R), 청색광(B), 적색과 청색의 혼합광(2:1비율)(R:B), 백색광(W), 적색광+UVA(RUV), 청색광+UVA(BUV), R:B(2:1)+UVA(RBUV) 총 8 종류 광에서 같은 광도($130{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$)와 광주기(명/암 = 16/8h)로 재배되었다. R이 들어간 모든 광 처리구(R, RB, RUV, RBUV)에서 정식 21일 부터 잎 상편생장(leaf epinasty)이 나타났다. RUV 처리구에서 R에 비해 엽장과 엽병은 유의적으로 감소되고 엽폭은 유의적으로 증가되어 엽형지수가 낮은 결과를 보였다. 하지만, BUV 처리구에서 B에 비해 엽장과 엽병의 길이가 유의적으로 증가되었고 엽폭은 유의적 차이가 없었으며 엽수는 유의적으로 많았다. RBUV 처리구에서는 다른 처리구보다 엽장이 가장 짧았으며 RB 처리구와 비교하여 생체중, 건물중 및 엽면적 유의차는 없었다. 정식 후 28일 째에 측정된 지상부 건물중은 R, RUV 및 BUV 처리구에서 유의적으로 높았고 W와 FL에서 유의적으로 낮았다. 엽면적은 BUV 처리구에서 유의적으로 가장 높았다. 정식 28일째에 시금치 아스코르브산 함량은 B 처리구에서 유의적으로 가장 높았고 그 다음으로 BUV에서 높았으며 FL과 R에서 유의적으로 낮았다. 따라서 식물공장에서 시금치 재배 시 생육과 품질적인 측면에서 BUV광이 가장 적합한 것으로 보인다.

• 한국연초학회지
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• 제3권1호
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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).

• 농촌계획
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• 제23권3호
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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.