• Research in Plant Disease
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• v.23 no.2
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• pp.168-176
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• 2017

Root-dipping inoculation method has been widely used to determine the resistance of watermelon to Fusarium oxysporum f. sp. niveum causing Fusarium wilt. Although this method leads to the precise results of plant disease responses, more rapid and efficient assay methods have been still required because the root-dipping inoculation method is labor-intensive and time-consuming. In this study, we established a simple and effective bioassay method based on the comparison of various inoculation methods and growth conditions. To develop the system, the occurrence of Fusarium wilt on four resistant and susceptible cultivars was investigated by four different inoculation methods, root-dipping, scalpel, tip and soil-drenching methods. Of these inoculation methods, scalpel method resulted in clear plant disease resistance responses with the simplicity. With the use of scalpel method, we also explored the disease development of the cultivars depending on inoculum concentration, growth stage of seedlings, and incubation temperature after inoculation. Furthermore, we found that the resistance degrees of 23 cultivars derived by scalpel inoculation method were similar to the results by root-dipping method established previously.

• Research in Plant Disease
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• v.22 no.3
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• pp.152-157
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• 2016

Root-dipping inoculation method has been used to investigate resistance of radish plants to Fusarium wilt. However, the method requires a lot of labor and time because of complicate procedure. This study was conducted to establish a simple and effective mass-screening method for resistant radish to Fusarium wilt. Radish seedlings of susceptible and resistant cultivars were used to investigate wounding method by scalpel, inoculum concentration, and pathogen-inoculated growth stage of seedlings. We established an efficient mass-screening method based on our results as following: Roots of 14-day-old seedlings of radish are cut with a scalpel at a $90^{\circ}$ angle to a 2 cm-depth at a 1 cm-distance from main stem and then inoculated by pouring with a 10 ml-aliquot of a fungal spore suspension ($1.0{\times}10^7conidia/ml$) on soil. The inoculated plants are cultivated in a growth room at $25^{\circ}C$ for about 4 weeks with 12-hour light a day. The proposed screening method enables to effectively select resistant from mass radish plants cultivars to Fusarium wilt.

• Hwankyungkyoyuk
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• v.4 no.1
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• pp.89-211
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• 1993

The Korean government embarked upon ambitious economic development plans in the 1960's the goals of development policy at that time were the elimination of absolute poverty and the alleviation of unemployment. With scant natural resources, the government had to push for industrialization based upon borrowed foreign raw materials with surplus local labor. Preoccupation with the economic goals of industrialization and export expansion left little room for considering environmental protection. It is evident that Korea's exported industrialization strategy of the past three decades has been a success in terms of income, production, and other macroeconomic indicators, but it cannot be denied that a host of undesirable side-effects have been created. These include environmental problems. congestion in several large cities, poor wealth distribution, and regional disparities. The environmental problems were recognized even in the early stage of development, but preoccupation with the pending economic goals of industrialization and export expansion left little room for considering environment protection. The perceived and actual seriousness of the problems, however, has reached such a level that further negligence may imperil political stability and developmental problems facing the world arise from a world economic order characterized by ever expanding consumption and production, which exhausts and contaminates natural resources and creates and perpetuates gross inequalities between and within nations. It will be necessary to develop new culture and ethical values, transform economic structures, and reorient, our lifestyles. Changing lifestyles can not be promoted by government policy initiative alone but through self=generated educational efforts and mutual training by people themselves. The citizens group for environment (NGOs) should assume these educational and training responsibilities starting from grass-root level of people. It must be reawakened to the reality that the environmental preservation for better quality of life is based on the development of human relationships, creativity, spirituality, reverance for the natural world and celebration of life, and is not dependent upon increased consumption of non-basic material goods. To carry on such environment education social movements and NGOs should (1) provides educational methodologies, which focus on values clarification and moving beyond clarification and moving beyond blame to constructive action. (2) provide training for leaders of business and industry, government, union and others on consumption and production. (3) initiate and support the training and work of environmental counselor who encourage responsible consumption. (4) cooperative with media to initiate and strengthen educational programs on the social environmental programs on the social environmental impacts of consumption and production and to build awareness of consumer responsibility and potential. Economic and social development can be compatible with environment protection : both can be achieved simultaneously. Effective environmental management depends on the various factors : political will, institutional arrangements, appropriate legislation, and availability of the requistite financial and technological resources, which is possible with a strong public awareness of the importance of environmental preservation.

• KDI Journal of Economic Policy
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• v.14 no.2
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• pp.155-187
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• 1992

The Korean economy has sustained high growth rate for almost three decades, that have been associated with the rapid expansion of manufacturing industries. In the beginning stage of development, the high growth of the Korean economy has been based on improvements in productivity obtained by the economies of scale. In that period, the improvements in productivity could be secured by the economies of scale in the export-oriented industries which are the labor- and material-intensive industries. In the latter half of the 1980s, the Korean economy went through rapid transition. Now Korea is at another juncture in its development process, where economic restructuring is critical to sustain high growth. However, economic restructuring in the 1990s call for much more concerted effort than before, since changes in internal and external conditions have profoundly altered the environment for economic development. If Korea is to sustain high growth in the 1990s, it has to promote balanced economic and social development in coordination with the smooth facilitation of industrial restructuring. There are no inherent conflicts among the issues involved, so they can be resolved by restructuring the economy to facilitate, in a global context, the development of knowledge- and technology-intensive activities and to ensure that the benefts of growth are reflected of qualitative improvements in national living standards. In this paper, we examined a scenario of structural changes using a mid- and long-term multisector model, in order to understand the conditions needed for realizing the growth potential. This examination explains the important features of the development course and policy directions that will help sustain high growth in the 1990s.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.699-705
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• 1997

This experiment was conducted to find out an optimum direct seeding date for rice in the southern alpine area of Korea as direct seeding method being considered as the most labor-saving method. A cultivar which was sprouted, Keumobyeo, was sown on the surface of flooded paddy from April 25 to May 15 with 5-day interval. The growth characters such plant height, tiller numbers, yield and its components as well as air temperatures were observed. Earlier sowing showed longer plant height and greater tillers than later sowing. Accumulated temperatures in the different growth stages varied from 1,010 to 1,052$^{\circ}C$ during the period from seeding date to maximum tillering stage, and from 1,785 to 1,846$^{\circ}C$ during the period from seeding to heading dates. The growth of rice sown up to May 5 showed comparatively good when compared to that of machine-transplanted rice, even though the grain yield was not competitive to that of machine-transplanted rice. Highly negative correlation coefficients were found between accumulated temperature during the period of first 30 days after seeding dates and the number of panicles, the number of spikelets per square meter, and grain yield. Regression equation between direct seeding date(X) and yield(Y;MT /ha) was $\hat{Y}$ =3.80990＋0.06207X-0.00174 $X^2$($R^2$=0.704), from which optimum seeding date for direct seeding method in alpine area was estimated to be on April 25 to May 1.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.3
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• pp.205-209
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• 2021

Barnyard millet (Echinochloa esculenta) can be processed through soiling, hay, and silage, depending on the weather conditions during harvesting. However, research on barnyard millet is insufficient, and standards for cultivar, seeding density, and fertilizers have not been established. This study was conducted to examine the effects of seeding density and seeding methods on dry matter yields. For this, we used the early-maturing (Shirohie millet) variety of the barnyard millet. The experimental design included different seeding density (10 kg/ha, 15 kg/ha, 20 kg/ha (standard seeding density), 25 kg/ha and 30 kg/ha), and different methods of seeding (drill seeding and broadcast seeding). The seeding date was May 13, 2021, and the harvest date was July 13, 2021. Harvesting was carried out when the heading reached 40 %. Lodging occurred at 5, 9 and 7 at 20, 25 and 30 kg/ha densities in the broadcast seeding, but not in the drill seeding. With decreasing density of seeding, tillage number showed an increasing trend in both drill seeding and broadcast seeding (p>0.05). The plant heights were comparable in both drill seeding and broadcast seeding (p>0.05). The heading stage of barnyard millet was checked July 7 for drill seeding, and, on July 8 for broadcast seeding. It took 62 days, i.e., till July 13 for the heading to reach 40 % of the output. The dry matter yield of barnyard millet was significantly higher at the seeding density of 30 kg/ha, for both the methods of seeding (p<0.05). There was no difference in the chemical composition of grain, based on the seeding method and seeding density. However, as the seeding density increased, the CP, NDF, ADF, and TDN contents increased in both drill seeding and broadcast seeding. We found that, the dry matter content was the highest at the seeding density of 30 kg/ha for both the methods of seeding, but this was only 1.3 times higher than that of 10 kg/ha. Considering the seed price and labor force involved in seeding, it is advisable to have a seeding density of 15-20 kg/ha.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.5
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• pp.32-39
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• 2021

Recently, necessities of steel form for reinforced concrete beam and girder have been emphasized in building structures for the reduction of the construction period and the labor cost. SY Beam was developed for the these purposes and is roll-formed using thin steel plate. On this research, we tried to evaluate and verify the performance and behavior of SY Beam under construction loading stage as like pouring in situ concrete. For the standard shape of SY beam, structural modelling with various steel thicknesses has carried out using MIDAS GEN program. From results of modelling, the width and height of SY Beam were determined 600mm and 400mm respectively. For 3 SY Beams, the loading experiment was performed to measure vertical and horizontal displacement under stacking sand, concrete block, and bundle of rebar. As a result, the vertical deflection showed a tendency to decrease as the thickness increased. In the horizontal displacement, the trend according to the thickness was not clearly observed. From the evaluation on the loading experiment, it is considered that the SY Beam can secure both workability and structural safety. In particular, the SY Beam(1.2mm) hardly generates horizontal displacement, so it has excellent load-bearing capacity. So, we judged that the SY Beam with 1.2mm steel plate has excellent performance and consider to be immediately commercially available.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.497-503
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• 2018

A strawberry variety 'Arihyang' was derived as an artificial cross between 'Tochiotome' and 'Seolhyang' in 2014. The seedling and line selections were conducted from 2014 to 2015. Preliminary and advanced yield trials of '14-5-5,' which was the final selected line, were conducted from 2015 to 2017. 'Arihyang' is suitable for forced cultivation and has strong plant vigor, uniformly large-sized fruit, and a high yield compared to those of the check variety, 'Seolhyang' and 'Maehyang.' Especially, vitamin C was at a significant level, which was approximately 15% higher than that of 'Seolhyang.' The average number of flowers per first flower cluster was 10.5, which could reduce the labor of thinning fruit. Its fruit has a conical shape, dark red color, and glossy skin. The fruit was of good quality but has recommendations for harvest at the fully ripened stage. 'Arihyang' has intermediate resistant to phytophthora crown rot, but is susceptible to powdery mildew, gray mold, anthracnose, and fusarium wilt. It is reguired to manage major diseases and pests using optimum cultivation techniques and chemical control.

• Journal of Popular Narrative
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• v.26 no.2
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• pp.221-247
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• 2020

This paper examines the meaning of Pyeongsari, the main stage of the novel 'Toji (Land )' and the original experience space engraved in the lives of the characters and suggests the direction of Pyeongsari as a 'Toji (Land )' content platform. Pyeongsa-ri, an imaginary space in the novel, starts from the background of the original work and turns into a representative tourist space for Ha Dong-gun. However, it is necessary to provide cultural experience-type contents that visitors can experience in person. In the original work, Pyeongsari is an ideal community and a symbol of the Korean modern history of suffering and pioneering. Therefore, taking advantage of this meaning, it is necessary to prepare a cultural experience space that shows Confucian culture, women's labor culture, and shamanic culture to draw on visitors' experiences. In addition, the app should be developed in connection with transformed works that have been the driving force behind the reorganization of Pyeongsari, and education and experience spaces using augmented reality are provided on the web. This interaction between digital and reality makes the meaning of the original or transformed works contemporaneous, while contributing to the visitor's own experience. In addition, through this, Pyeongsari can evolve into a cultural experience content platform that reflects the meaning of Korean culture and life. This paper is significant in that it suggests the direction of Pyeongsari's space planning for the 'geography of meaningful places'. In addition, while showing how the imaginary space of the original literary work has reorganized the space of reality, there are implications for the media content of the literary work and the terrain of the culture and arts industry.

• Korean Journal of Culture and Social Issue
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• v.28 no.3
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• pp.513-527
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• 2022

This study was conducted to examining the socio-cultural impact of the COVID-19 pandemic that swept the world around 2020, and the transformation of norms and social problems due to COVID-19. For this, the characteristics of changes in the socio-cultural norms of the 14th century European Black Death, a representative example of the pandemic, were derived, and based on this, the COVID-19 pandemic was analyzed. The Black Death served as an opportunity to change social norms based on the existing religious authority and the power of the feudal system to the Enlightenment. The population declination and labor shortage also promoted commercialization and mechanization. Printing, which spread during this period, led to the popularization of knowledge, which raised the level of thinking and led to epochal scientific development. This became the foundation of the Industrial Revolution. Like the recent Black Death, COVID-19 has triggered changes in social norms. The technological environment of metaverse, a mixture of virtual and reality, has changed the norm of a consistent identity into free and open identities exerting various potentials through alternate characters. In addition, meme, which are about people being friendly to those with the same worldview as him on the metaverse, weakened the sense of isolation in non-face-to-face situations. Artificial intelligence (AI), which developed during the COVID-19 pandemic, has entered the stage of being used for creative activities beyond the function of assisting humans. Discussions were held on what new social problems would be created by the social norms changed due to the COVID-19 pandemic.