• Korean journal of applied entomology
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• v.60 no.3
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• pp.315-322
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• 2021

This study investigated the acaricidal and repellent activities of various plant extracts and Cnidium officinale-derived materials against Haemaphysalis longicornis. Among the 24 methanolic plant extracts, C. officinale showed the highest acaricidal activity (93.3%) against H. longicornis. Platycodon grandiflorus, Phytolacca americana, Magnolia denudata, Houttuynia cordata, C. officinale, and Pueraria montana showed significant differences in their repellent activity. Consequently, the activity of solvent-fractionated materials and the derived material of the C. officinale, was investigated and a 90% acaricidal effect was observed three days after hexane fraction treatment, indicating that the repellent response was statistically significant. Butylidenephthalide, which is a C. officinale-derived compound, showed 90% acaricidal activity seven days after treatment. Additionally, all H. longicornis moved to the untreated area in the t-tube olfactometer experiment, confirming the repellent activity of butylidenephthalide. Therefore, the results of this study suggest the use of C. officinale crude extract and butylidenephthalide as potent acaricidals and repellents against H. longicornis, respectively.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.70-70
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• 2019

본 연구는 인천시 강화군 퇴모산(338m) 일원을 중심으로 식물상을 조사하였다. 관속식물은 76과 210속 268종 3아종 27변종 3품종으로 총 301분류군으로 조사되었다. 분류군별로 양치식물이 4과 5분류군, 나자식물 2과 4분류군, 쌍자엽식물이 61과 226분류군, 단자엽식물이 9과 66분류군이 확인되었다. 주요 식물로 특산식물은 할미밀망(Clematis trichotoma), 백운산원추리(Hemerocallis hakuunensis), 늦둥굴레(Polygonatum infundiflorum)로 3분류군, 희귀식물은 관심대상종(Least Concern)인 두루미천남성(Arisaema heterophyllum), 정보부족종(Data Deficient)인 늦둥굴레(Polygonatum infundiflorum)로 2분류군이 확인되었다. 침입 외래식물은 돼지풀(Ambrosia artemisiifolia), 미국자리공(Phytolacca americana), 좀명아주(Chenopodium ficifolium), 달맞이꽃(Oenothera biennis L.), 털별꽃아재비(Galinsoga ciliata (Raf.) S.F.Blake) 등 10과 20분류군이 조사되었다. 유용식물로는 용도를 모르는 49분류군(16.3%)을 제외하면 252분류군(83.7%)이 자원식물로 이용가치가 있는 것으로 나타났다. 이들을 용도에 따라 구분해보면 식용 130분류군(29.4%), 섬유용 3분류군(0.7%), 약용 106분류군(24.0%), 관상용 34분류군(7.7%), 사료용 141분류군(31.9%), 산업용 3분류군(0.7%), 염료용 10분류군(2.3%), 목재용 15분류군(3.4%)으로 조사되었다.

• Korean Journal of Plant Resources
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• v.34 no.1
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• pp.103-113
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• 2021

This study was investigated to find out the distribution of flora and remarkable plants and factors and management measures for influx of wild disturbed plants in the Damyang area of Mudeungsan National Park. The field survey was carried out 8 times from May 2019 to October 2020. First of all, in the Damyang area of Mudeungsan National Park, a total of 603 taxa in 107 families, 349 genera, 531 species, 57 varieties, 5 subspecies and 10 forms. This result was found to be about 12.33% of the total 4,881 taxa of vascular plants in Korea. In addition, Rare plants were classified as 15 taxa. Floristic special and Korean endemic plants were identified as 85 taxa and 13 taxa, respectively. Lastly, the naturalized plants that appeared in the Damyang area of Mudeungsan National Park were observed in 45 taxa with 45 species of 16 families and 36 genera. Moreover the naturalization rate was 7.46% and the urbanization index was calculated to be 14.01%. The wild disturbed plants were found in a total of 4 taxa. Especially, a sheep sorrel(Rumex acetosella) was focused on managing for physica and biological control at Sinseondae Eoksaepyungjeon.

• Korean Journal of Environment and Ecology
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• v.35 no.1
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• pp.1-23
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• 2021

This study conducted a survey on flora at Mt. susdolbon(508m), Mt. seongjubong (625.3m), and Mt. sulibong(596.2m), located in Yanggu-gun, Gangwon-do. A total of 403 taxa, including 6 forms, 43 varieties, 4 subspecies, 350 species, 255 genera, and 84 families, were surveyed in the three mountain areas. 18 taxa from 5 families of ferns, 3 taxa from 1 family of gymnosperms, and the dicotyledonous plants as 302 taxa from 69 families of the dicotyledonous plants were identified. The remarkable plants included 11 taxa of the Korean endemic plants, such as Populus tomentiglandulosa, Salix koriyanagi, Cimicifuga heracleifolia, Aconitum pseudolaeve, Clematis trichotoma, Echinosophora koreensis, Vicia chosenensis, Salvia chanryoenica, and Hemerocallis hakuunensis. The rare plants designated by the Korea Forest Service were 4 taxa, including Echinosophora koreensis as endangered species (EC), Cimicifuga heracleifolia, Epimedium koreanum, and Lilium cernuum. The Least Concern species (LC) were 13 taxa, including Persicaria orientalis, Exochorda serratifolia, Viola diamantiaca, Lithospermum erythrorhizon, and Trigonotis icumae. The invasive alien plants were 28 taxa, including Persicaria orientalis, Rumex crispus, Phytolacca americana, Cerastium glomeratum, Chenopodium album, Chenopodium ficifolium, Amorpha fruticosa, Robinia pseudoacacia, Trifolium pratense, Trifolium repens, Oxalis dillenii, Euphorbia supina, and Oenothera biennis, accounting for 6.9 percent of the 403 taxa of the surveyed plants.

• Korean Journal of Environment and Ecology
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• v.37 no.1
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• pp.35-58
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• 2023

In this study, we conducted a flora survey at Mt.Bakdal (363m) and Mt. Myeongbong (245.3m) in Paju-si, Gyeonggi-do. A total of 405 taxa, including 2 forms, 32 varieties, 8 subspecies, 363 species, 261 genera, and 87 families, were surveyed in the two mountain areas. The ferns were identified as 12 taxa from 6 families, the gymnosperms as 6 taxa from 2 families, the dicotyledonous plants as 290 taxa from 70 families, and the monocotyledonous plants as 97 taxa from 9 families. The remarkable plants included 8 taxa of the Korean endemic plants, which were Populus tomentiglandulosa, Salix koriyanagi, Clematis brachyura, Viola seoulensis, Forsythia koreana, Paulownia coreana, Weigela subsessilis, and Hemerocallis hakuunensis, and 3 taxa of the rare and endangered plants as designated by the Korea Forest Service, including Tylophora floribunda as Vulnerable (VU) species, and Viola albida and Chionanthus retusus as Least Concern (LC) species. The invasive alien plants were 35 taxa, including Rumex crispus, Phytolacca americana, Cerastium glomeratum, Chenopodium album, Chenopodium ficifolium, Lepidium virginicum, Amorpha fruticosa, Robinia pseudoacacia, and Trifolium repens, accounting for 8.5 percent of the 405 taxa of the surveyed plants. We intend to further identify plants through the studies on unsurveyed areas in the western part of the DMZ, identify the native habitats of rare and specialty plants, and use them as basic data for managing ecosystem-disturbing plants.

• The Journal of Engineering Geology
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• v.12 no.1
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• pp.95-109
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• 2002

A significant question is what role does newly-formed expansive mineral growth play in the premature deterioration of concrete. These minerals formed in cement paste as a result of chemical reactions involving cement paste and coarse/fine aggregate. Petrographic observations and SEM/EDAX analysis were conducted in order to determine chemical and mineralogical changes in the aggregate and cement paste of samples taken from lowa concrete highways that showed premature deterioration. Formation and expansive mechanisms involved in deterioration were Investigated. Brucite, Mg(OH)$_2$, is potentially expansive mineral that farms in cement paste of concretes containing reactive dolomite aggregate as a result of partial dedolomitization of the aggregate. No cracking was observed to be spatially associated with brucite, but most brucite was microscopic in size and widely disseminated in the cement paste of less durable concretes. Expansion stresses associated with its growth at innumerable microlocations may be retrieved by cracking at weaker locations in the concrete. Ettringite, 3CaO.Al$_2$O$_3$.3CaSO$_4$.32$H_2O$, completely fills many small voids and occurs as rims lining the margin of larger voids. Microscopic ettringite is common disseminated throughout the paste in many samples. Severe cracking of cement paste causing premature deterioration is often closely associated with ettringite locations, and strongly suggests that ettringite contributed to deterioration. Pyrite, FeS2, is commonly present in coarse/fine aggregates, and its oxidation products is observed in many concrete samples. Pyrite oxidation provides sulfate ions for ettringite formation.

• The Korean Journal of Pesticide Science
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• v.8 no.3
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• pp.220-230
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• 2004

This study was conducted of Korean native plants to screen herbicidal activity which could be used for the development of new natural herbicides. Ninety-eight plants were collected from Wan Island, Chollanamdo in Korea and their methanol extracts were obtained. Herbicidal activities of the methanol extracts were determined by seed bioassay using canola (Brassica napus L.) seedlings. Among ninety-eight species, twenty plants were highly herbicidal ($GR_{50}<1,000\;{\mu}g\;g^{-1}$): Abies holophylla MAXIM., Ailanthus altissima (MILL.) SWINGLE, Anthemis nobilis L., Aralia elata SEEM., Artemisia iwayomogi KITAMURA, Asarum sieboldii MIQ., Brassica campestris subsp. napus var. nippo-oleifera MAKINO, Clematis terniflora DC., Crataegus scabrida SARG., Gnaphalium affine D. DON, Jasminum nudiflorum LINDL., Kalopanax pictus (THUNE.) NAKAI, Machilus japonica S. et Z., Myrica rubra S. et Z., Osmunda japonica THUNB., Phytolacca esculenta V. Houtte, Platanus occidentalis L., Quisqualis indica L., Rubus hirsutus THUNB., Yucca smalliana FERN. Fifty plants were shown moderate herbicidal activity $(1,000\;{\mu}g\;g^{-1}, however, twenty-eight plants were not shown any herbicidal activity.

• Journal of the Korean Geotechnical Society
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• v.37 no.8
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• pp.51-58
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• 2021

South Korea, as the 10th country to join the Artemis program led by NASA, is actively supporting various researches related to the lunar exploration. In particular, the utilization of water as a resource in the Moon has been focused since it was discovered that ice exists at the lunar pole as a form of frozen soil. Information on the thermal conductivity of lunar regolith can be used to estimate the existence for ice water extraction by thermal mining. In this study, the vacuum pressure effect on thermal conductivity of KLS-1 was investigated with a DTVC (Dusty Thermal Vacuum Chamber). The reliability of KLS-1 was reconfirmed through comparison with thermal conductivity of known standard lunar regolith simulants such as JSC-1A. An empirical equation to assess thermal conductivity considering dry unit weight and vacuum pressure was proposed. The results from this study can be implemented to simulate lunar cryogenic environment using the DTVC.

• The Korean Journal of Ecology
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• v.23 no.3
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• pp.223-229
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• 2000

To develop the restoration technique from urban planted forest to natural forest, sprout growth and its effects on vegetation composition in the early stage after lumbering, were studied, using only Populus albaglandulosa of the tree layer in Chungdam Park Chungdam-dong, Kangnam-gu, Seoul during the two years from 1997 to 1998. The results were as follow. After lumbering, the more basal areas of the parent stump, the more sprouts were generated. The basal area of parent stump was related more to biomass than to the number of sprouts. In the cutting area, biomasses of sprouts were 552.7 g?DW/㎡ in first year and 8.7 g?DW/㎡ in second year after lumbering. Therefore, cutting of sprouts in first year resulted in decrease of sprout production in second year. In the non-cutting area, biomass of sprouts was 657.4 g?DW/㎡ and more than that of the experiment. Especially, 2-year sprouts grew to a 304 cm height by the end of the growing season in the second year. The growing season of sprouts was from early April to early September and almost all the leaves of the sprouts remained at the end of the growing season. Specific leaf area decreased along with time elapse and plant height but the differences were not conspicuous. Therefore, it is thought that the reason why p. albaglandulosa sprouts grew fast was due to a long growing period and lower layer leaves which remained at the end of the growing season. In the cutting area of the P. albaglandulosa sprouts, there were no changes in the number of species in the shrub layer but an conspicuous increase in the herb layer. Coverage was no changes in the shrub layer but an increase in the herb layer. In the non-cutting area of P albaglandulosa sprouts, the number of species and the coverage changed a little, and the main species of the herb layer were Phytolacca americana, Eupatorium rugosum and Panicum dichotomiflorum, which are tall plant species.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.8 no.3
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• pp.85-96
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• 2013

Entrepreneurship courses and programs in Korean universities tend to increase steadily but seem to have some limitations. They are usually recognized as another domain of Business Administration. Entrepreneurship program is practical like Business Administration but should be much more interdisciplinary than that. Because Korean Entrepreneurship programs are in the early stage, they must be reinforced with factors such as education culture, faculties, curriculum and relationships with communities. This study aims to get some implications from Entrepreneurship programs have been run by universities in America in order to facilitate Entrepreneurship program in Korean universities. Based on 11 success factors found by our case universities' Entrepreneurship programs and Kauffman Campus, this study has drawn implications of critical success factors of Entrepreneurship programs as follow. First of all, because Entrepreneurship programs should focus on Entrepreneurship mind sets such as innovative idea generation and courage to overcome risk, it is more desirable that Entrepreneurship programs are introduced in all departments of universities such as Arts, Science and Engineering. These programs also need to take interdisciplinary approach and required to be opened from liberal arts course. In order to be sustained during all their academic careers, vision, mission and strategy for Entrepreneurship programs should be based on strong leadership and support of top leaders. Entrepreneurship culture of each university is also one of the most important success factors. Entrepreneurship programs not only as major programs but also as specific Entrepreneurship minors designed for departments such as Arts, Science and Engineering could be considered according to each university's situation. This study also suggest to make a motivation system for Entrepreneurship faculties, Ph d. programs for Entrepreneurship, communication network for Entrepreneurship programs and mentor system in community. To begin Entrepreneurship programs, it also needs to develop good education contents as many as possible. When it concerned with teaching method, project based 4 year program can be suggested to be effective and efficient. To introduce project based program that should be consistent till participants' graduation, university must prepare regulations to support team teaching, mentor and interdisciplinary cooperation. To dissipate the concept that Entrepreneurship is another version of management, this study support the idea that Entrepreneurship programs should be designed and run by independent and central-focused governance system, Entrepreneurship education center.