• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.977-986
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• 1996

The uncertainty of rains at the onset of wet season (WS) and the drought risk involved hinder growing more than one rainfed lwoland rice crop per year. Establishing transplanted rice well into the WS leaves insufficient moisture in the soil for subsequent crop. Rice establishment early in the season gives the farmer better opportunities to grow a crop after rice. An experiment was conducted startign in 1993 to evaluate dry seeding of rice through slit soil seeding. It is done utilizing the vertical metering slit seeder for conserving soil moisture coming from the first rains in the early WS to sustain germination and establishment of the seeding at least until the succeeding rains under therainfed lowland (RL) environment. The treatment consisted of slit-seeding the PSBRc 14 into the tilled and nontilled plots at 100kg/ha and at depths of <10 mm (shallow seeding) and 60-70m (deep seeding). The control treatment was broadcast seeded on tilled soil and harrow to cover the seeds The superior crop establishment observed in 1995 WS experiment on nontilled, slit-seeded plots confirmed the results observed in 1993 WS and 1994 WS experiments. Emergence in deep seeding was not significantly different from shallow seeding in nontilled plots giving an average yield of 2.1 t/ha in all slit-seeded plots. This offers an advantage of reduced energy in put in nontilled shallow seeding. However, heavy weed infestation has to be addressed at the early stage of rice in nontilled soil to get the full advantage from slit seeding. The consistently better crop establishment observed in slit seeding over that of broadcast seeding in the WS of 1993, 1994 and 1995 also demonstrates that the slit seeding technology can be adopted with confidence in the rainfed lowland field condition to reduce the risks involved in broadcast seeding.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.5 s.182
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• pp.143-148
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• 2006

It is still very difficult to generate a geometry model and finite element model, which has complex and many free surface, even though 3D CAD solutions are applied. Furthermore, in the medical field, which is a big growth area of recent years, there is no drawing. For these reasons, making a geometry model, which is used in finite element analysis, is very difficult. To resolve these problems and satisfy the requests of the need to create a 3D digital file for an object where none had existed before, new technologies are appeared recently. Among the recent technologies, there is a growing interest in the availability of fast, affordable optical range laser scanning. The development of 3D laser scan technology to obtain 3D point cloud data, made it possible to generate 3D model of complex object. To generate CAD and finite element model using point cloud data from 3D scanning, surface reconstruction applications have widely used. In the early stage, these applications have many difficulties, such as data handling, model creation time and so on. Recently developed point-based surface generation applications partly resolve these difficulties. However there are still many problems. In case of large and complex object scanning, generation of CAD and finite element model has a significant amount of working time and effort. Hence, we concerned developing a good direct finite element model generation method using point cloud's location coordinate value to save working time and obtain accurate finite element model.

• Research in Plant Disease
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• v.7 no.3
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• pp.134-139
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• 2001

Effects of tomato-juice and KH$_2$PO$_4$ as exogenous nutrients on the infection of Botrytis cinerea LVF12 and pathogenicity to tomato were investigated. B. cinerea LVF12, which was previously reported as a casual agent of the gray mold rot of perilla, was used for pathogenesis on tomato leaves. No infection was induced, and no lesion developed on tomato leaves by the conidial suspension of LVF12 when the inoculum was prepared in sterilized water. However, when the conidial suspensions of LVF12 added with various concentrations and conditions of tomato-juice were inoculated on whole tomato plants, the disease was induced readily, Among them, 20% tomato juice with 0.1M KH$_2$PO$_4$ appeared to be the most suitable nutrient to promote high disease incidence on tomato. For the pathogenicity test according to the growing stage of tomato, the mature leaves were more susceptible than seedlings. Symptoms on the infected plants were initial small gray spots at the inoculated area. Later the whole leaves, petioles and stems became gray and eventually fell off, Under high humidity conditions, the diseased leaves and stems were covered with gray hyphae and conidia. All symptoms of infected plants were identical to those in the field conditions.

• The Plant Pathology Journal
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• v.36 no.1
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• pp.54-66
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• 2020

This study was conducted to evaluate usefulness of numerical weather prediction data generated by the Unified Model (UM) for plant disease forecast. Using the UM06- and UM18-predicted weather data, which were released at 0600 and 1800 Universal Time Coordinated (UTC), respectively, by the Korea Meteorological Administration (KMA), disease forecast on bacterial grain rot (BGR) of rice was examined as compared with the model output based on the automated weather stations (AWS)-observed weather data. We analyzed performance of BGRcast based on the UM-predicted and the AWS-observed daily minimum temperature and average relative humidity in 2014 and 2015 from 29 locations representing major rice growing areas in Korea using regression analysis and two-way contingency table analysis. Temporal changes in weather conduciveness at two locations in 2014 were also analyzed with regard to daily weather conduciveness (C_i) and the 20-day and 7-day moving averages of C_i for the inoculum build-up phase (C_inc) prior to the panicle emergence of rice plants and the infection phase (C_inf) during the heading stage of rice plants, respectively. Based on C_inc and C_inf, we were able to obtain the same disease warnings at all locations regardless of the sources of weather data. In conclusion, the numerical weather prediction data from KMA could be reliable to apply as input data for plant disease forecast models. Weather prediction data would facilitate applications of weather-driven disease models for better disease management. Crop growers would have better options for disease control including both protective and curative measures when weather prediction data are used for disease warning.

• Korean Journal of Medicinal Crop Science
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• v.11 no.2
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• pp.122-126
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• 2003

This study was conducted to investigate plant growth characteristics and anatomical studies of Korean mistel (Viscum album var. coloratum (Kom.) Ohwi). Parasite position was upper part that has a plenty of sunshine area 5 to 10m apart from the ground, regardless host tree. Stem developed two branch stems from the each basal stem, leaf was grown from the end stems as opposite. Fruit has a light yellow color and berry size was 7 to 8 mm long diameter and it contains seed. Floral bud differentiation initiated with forming rounded dome and arch-shaped floral apex at the beginning stage, and produced heart-shaped sepal following the differentiation of leaf primordia. Floral bud formation processed centeral part first and following bilateral sides were developed in order. Leaf was thick and stoma and guard cell were observed from the two or three inner layers from the epidermis. Mistletoe penetrated cork cambium of host plant and was growing by rooting on xylem. Korean mistel connected to host plant through parasitic organ, haustorium structurally and physiologically.

• Korean Journal of Medicinal Crop Science
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• v.26 no.3
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• pp.205-213
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• 2018

Background: Since the revised Ginseng Industrial Act was passed, ginseng sprouts have become a new medicinal vegetable for which there is high consumer demand. However, the existing amount of research and data on ginseng production has not kept pace with this changed reality. Methods and Results: In this study we analyzed the changes in the amounts of ginsenosides in different parts of growing ginseng sprouts during the period from when organic seedlings were planted in nursery soil until 8 weeks of cultivation had elapsed, which was when the leaves hardened. In the leaves, ginsenoside content increased 1.62 times with the panaxadiol (PD) system and 1.31 - 1.56 times with the panaxatriol (PT) system from 7 to 56 days after transplantation. During the same period, the total ginsenoside content of the stems decreased by 0.66 - 0.91 times, and those of the roots increased until the $21^{st}$ day, and then underwent steep declines. The effect of fermented press cake extract (FPCE) and tap water (TP) on the total amount of ginsenoside per plant were similar, and could be represented with the equations $y=1.4330+0.2262x-0.0008x^2$ and $y=0.9555+0.2997x-0.0031x^2$ in which y = ginsenoside content x = amount of and on the total amounts of FPCE or TP, respectively after 26.4 days, however, the difference between ginsenoside content with FPCE and TP widened. Conclusions: These results suggested that the amounts of ginsenosides in different parts of ginseng varied with the cultivation period and nutrient supply. These findings also provide fundamental data on the distribution of ginsenosides among plant parts for 2-year-old ginseng plants in the early-growth stage.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.7 no.4
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• pp.12-18
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• 2011

The renewed global interest in nuclear power has arisen from the need to reduce greenhouse gas emissions and to provide sufficient electricity for a growing global population. Many countries with nuclear power plants (NPPs) are still implementing license extensions of 10~20 years, and even consideration is being given to the concept of life-beyond-60, a further period of license extension from 60 to 80 years. To solve the materials aging problem is integral to its success. A foundation for effective aging management of nuclear power plants is that aging is properly taken into account at each stage of a plant's lifetime, i.e. in design, manufacture, construction and operation including long term operation and decommissioning. To evaluate the plant aging phenomena, a lot of background information such as materials and environment of the parts of the reactor and plant systems is needed by the experts. Information on degradation mechanisms is also used. In this paper, a regulation on the integrated materials aging management for nuclear facilities is proposed. The proposed regulation identifies key elements of effective aging management for nuclear power plants and provides the requirements on aging management for nuclear facilities throughout all stages of the lifetime of the plant.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.3 s.43
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• pp.233-242
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• 1992

This study primarily concentrates on the Fashion Style of the New Generation which has come into being in 1980 with reference to the contents of the newspaper and magazine in 1950's. . The New Generation has undergone the social and cultural change under the effect of mass communication, mass consumption brought by the economic development, sports boom promoted during the period of Asian Games and Seoul Olympic Games and the adoption of the policy for the autonomous school uniform. In the process of the social and cultural change, they have the common peculiarity such as sensitivity, anthoritarianism and polarity and they have taken an important part in the development of the 'Young Fashion' The characteristics of their fashion styles are divided into three periods as follows; 1. The rising period (1980-1982): The most important pecuriality of the first step can be sum up to the following point. The free fashion style replaced the formal one such as T-shirt or casual wear comes into as a everyday dress. Moreover, many people become interested in the New Fashion which is gradually diversified and high-qualified. As a natural consequence, the lively interest of the people has brought into the appearance and competition of the New Brand in fashion industry 2. The growing period (1983-1986): Mannish Look, so-called 'New Fashion' gained the summit of the fashion and change over conservatively. However, 'Mannish Look' have great effect on the Fashion Style until now on. Specially in Korea, 'Punk Style'and 'Androgynous Look' can be an example among many. 3. The diversifying period (1987-1989): The Fashion Style has developed variously even though the Reactionism takes the lead as the main current of the Korean Fashion. Moreover, it is noticeable that man comes into the stage as a new fashion group and the fashion market begins to dear in various lines of goods with moderate and low prices. These various aspects can be regarded as diversification in the Fashion Style as the needs in the times and society.

• Korean Journal of Environmental Agriculture
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• v.2 no.2
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• pp.103-107
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• 1983

The effect of photochemical oxidants on rice plants was measured by growing the rice plants Nihonbare in pot in charcoal-manganese oxide filtered atmosphere and non-filtered air. Visible injury on the leaf blades of rice plants were observed in plants grown under the unfiltered air chamber, but plants under filtered air chamber were free from any injury. Fresh weight of stem and root at maximum tillering stage in unfiltered chamber were 16.8 and 46.4% less than filtered air chamber, respectively. Grain yield in unfiltered air chamber was also reduced by 14.7% compared to that of filtered air chamber. And the reduced yield paralleled increase in concentration of oxidants in the atmosphere at the experimental site. ABA content in rice plants cultivated in unfiltered air chamber was higher than in filtered air chamber, but the root activity of rice plants in unfiltered air chamber was remarkably decreased.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.6
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• pp.71-85
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• 2011

In Okdong coal mine abandoned area, every year large amount of mine wastes have been swept away due to heavy rains in summer. Because pH of coal-mine waste is in the early 4, plant naturally does not grow there due to unfavorable condition for growing plant. This study had an experiment to grow plant for 6 months using Mycorrhizae which can be adapted well in acid soil. As a result of Experiment, In the infected experiment pot, 90% of the plants survived but in case of uninfected experiment pot, only 25% were alive. From Growth Experiment, it appeared that average stem length increase (cm/month), average fresh weight increase ($g^{fw}/month$), average dry weight increase ($g^{dw}/month$) were increased by 60%, 21%, 31% respectively. Especially, Mycorrhizae plays an important role in providing nutrients and water when seeding are established. Mycorrhizae prevents death caused by lack of nutrients and water and helps growth and development of plant when seeding are established in the early stage. This study proved that Mycorrhizae is comparatively effective in plant growth and prevention of erosion in coal-mine abandoned area.