• Korean Journal of Medicinal Crop Science
• /
• v.14 no.3
• /
• pp.153-157
• /
• 2006

Floret flowering of Orostachys japonicus, a monocarpic and short day plant, should be controlled to continue cultivating. The study was done to examine the effect of transplanted seedling size (large, 18 leaves; medium, 13 leaves; small, 8 leaves) on growth, morphological characters, and flowering. Night-break treatment of 2 hours at midnight were done on August 25 and afterward samples were taken every 2 weeks. Growth, morphological and flowering related characters were measured from each sample. With larger seedling transplanted, plant height, inflorescence length, number of leaves including bracts and stem diameter were increased. Leaves and bracts, stem, root, shoot and total dry weights were increased as transplanted seedlings became larger. Although formed florets were inclined with larger transplanted seedling, they were not flowered because of the night-break treatment, meaning that the larger transplanted seedlings, the more economic yield.

• Korean Journal of Medicinal Crop Science
• /
• v.15 no.4
• /
• pp.251-255
• /
• 2007

Floret flowering of a monocarpic plant Orostachys japonicus should be controlled to change its harvest time. The study was done to clarify the effect of pinching time of inflorescence with many florets (Aug. 25, Sept. 8 and 22, Oct. 4) on its growth, morphological characters, and flowering. Night-break treatment of 2 hours at midnight were done since Aug. 25 when afterward samples were taken every 2 weeks to Nov. 4. Growth, morphological and flowering related characters were measured from each sample. Plant height, inflorescence length and number of leaves including bracts showed significant difference between the treatments because they were sharply increased until each pinching time. Stem diameter did nearly same. Leaf and bract, floret, shoot and total dry weights had similar response to the plant height, but stem and root dry ones did similar response to the stem diameter. Most florets were removed by the pinching treatments after formed ones were increased until each pinching time. Few florets were left after the treatment, meaning that night-break treatment after that could be skipped.

• Korean Journal of Medicinal Crop Science
• /
• v.15 no.4
• /
• pp.256-260
• /
• 2007

Year-round cultivation of a monocarpic plant Orostachys japonicus should be possible in case to controlling floret flowering. To give some information on its year-round cultivation, this study was carried out to examine the effect of night-break treatment time (June 10, Aug. 25) on its growth, morphological characters, and flowering. Night-break treatment of 2 hours at midnight were done since Aug. 25 and heating were made under $20^{\circ}C$ Samples were taken every 4 weeks from Aug. 25. Growth, morphological and flowering related characters were measured from each sample until March 9. Plant height, inflorescence length, number of leaves including bracts and stem diameter were greater in the earlier treatment than in the later one. Leaves and bracts, floret, stem, root, shoot and total dry weights showed the same response as plant height did to the night-break treatment time. Florets were more formed in the earlier treatment than in the later treatment in which they were flowered only on March 9, meaning that its year-round cultivation should be possible under night-break treatment before bolting and heating during winter season.

• Korean Journal of Medicinal Crop Science
• /
• v.16 no.1
• /
• pp.16-19
• /
• 2008

Shoot parts of a monocarpic and short day plant Orostachys japonicus have been used as a herbal medicine. The study was carried out to examine the effect of transplanting time (May 30, June 30, July 30) of its seedlings on its growth, morphological characters, and flowering. Two hours night-break treatment at midnight was done since Aug. 25 when samples were taken afterward every 4 weeks. Growth, morphological and flowering related characters were measured from each sample. Plant height and inflorescence length became longer with delayed transplanting time. Number of leaves including bracts and stem diameter were more and thicker when transplanted on June 30 than two other treatments. Leaves and bracts, stem, root, shoot and total dry weights showed nearly the same result to the number of leaves although floret dry weight were increased as transplanting time was delayed. Although florets were most formed when transplanted on June 30, they were not flowered because of the night-break treatment, meaning that the transplanting time had little effect on its growth and anthesis of the florets.

• Journal of Wetlands Research
• /
• v.10 no.1
• /
• pp.39-47
• /
• 2008

An eco-washland is increasingly getting attentions as a new alternative plan for management of water resources because of role as flooding control and ecological park without social and ecological side effects. However, there is a lack of study regarding technological development and ecological guidelines to create eco-washland. This study was carried out to suggest ecological guidelines necessary for engineering process to create eco-washland. A study site was the lower reach of Seokjang stream connecting to Yimjin river, a candidate of new eco-washland, and Kumsa area in Namhan river was selected as a reference site. The analysis of ecological characteristics focused on vegetation, fishes, and birds. Major vegetation communities, composed of dominant species such as Salix koreensis, Salix gracylistyla, Miscanthus sacchariflorus, Phragmites communis, etc., formed physical conditions along with other land uses including open water, sandbar, cultivated land, etc. Dominant species of fishes were some species belonging to Cyprinidae and Acheilognathinae, and in case of birds Anser albifrons, Anas platyrhychos, Anas poecilorhyncha belonging to waterbirds and Paradoxornis webbinanus dependent to forest edge were dominantly distributed. The results showed that complex wetland types associated with partially deep water and upland was the optimal eco-hydrological condition of washland. Cyprinidae and Acheilognathinae in case of fish and Egretta spp. (spring season) and Anas spp. (winter season) in case of bird were selected as target species for the these wetland types. Finally, a detail planning criteria to create habitats of these target species were discussed in terms of spawning, breeding, feeding, resting, refuge, nesting, etc.

• Korean Journal of Medicinal Crop Science
• /
• v.13 no.4
• /
• pp.186-189
• /
• 2005

Plant flowering should be mainly affected by temperature and daylength. The study was carried out to measure the effect of temperature during winter on growth and floret flowering of Orostachys japonicus grown under 2 hour night break. Temperature was controlled above $10^{\circ}C$ and $20^{\circ}C$ as heating boilers were run below them to compare the natural temperature. Night-break treatment was done on August 25 and afterward samples were taken every 4 weeks to check growth, morphological and flowering related characters. Plant height, inflorescence length, number of leaves including bracts and stem diameter were increased in heating temperatures of > $10^{\circ}C$ compared to natural temperature although similar in the two heating ones. Leaves and bracts, florets, stem, root, shoot and total dry weights showed the same response as the above morphological and flowering related characters. Florets were more formed but less flowered with higher temperatures. Anthesis rates of individual plant were 100% in natural temperature, 25% in > $10^{\circ}C$ heating temperature but none in > $20^{\circ}C$ heating temperature.

• Journal of the Korean Geographical Society
• /
• v.45 no.1
• /
• pp.165-183
• /
• 2010

For the study of the development of Asia map made by european map makers, one should consider Gog and Magog which existed in the maps for more than 700 years. Gog and Magog are described as an apocalyptic people in the Bible and medieval literature, and they are important elements in medieval mappaemundi and early modem world maps. This study classified representation types of Gog and Magog in old western maps. Maps were classed in to six categories according to the location and ethnic groups which they represent, and they were discussed in cartographic context. The maps until the fourteenth century place Gog and Magog, shut up by Alexander, near Caspian Sea. In the fifteenth century, Gog and Magog were described as Closed Jews in maps. From the sixteenth century they appear in the far northeastern part of Asia and they are named as Amagog or Ung and Mongul. In the mid-seventeenth century, they are located in Eastern Siberia by French cartographers. But with the expansion of geographic knowledge, Gog and Magog disappeared completely in the eighteenth century. In general, God and Magog were represented on the basis of traditional lore rather than on the Bible, and they became one means of mapping others of European community.

• Korean Journal of Medicinal Crop Science
• /
• v.15 no.6
• /
• pp.429-433
• /
• 2007

Shoot weight of Orostachys japonicus should determine its profitability. The study was carried out to measure the effect of nitrogen (N) fertilization level (0, 5, 10, 20kg/10a) on its growth, morphological characters, and flowering. Night-break treatment of 2 hours at midnight were done since Aug. 25 when afterward samples were taken every 4 weeks to Nov. 16. Growth, morphological and flowering related characters were measured from each sample. Plant height, inflorescence length, number of leaves including bracts and stem diameter were decreased with increased N levels. Leaf and bract, floret, shoot and total dry weights as well as withering rate showed similar response to the above morphological characters. Florets were less formed with increased N levels but were not flowered due to the night-break treatment, meaning that N fertilization had little effect on its growth and anthesis of the florets.

• Korea Science and Art Forum
• /
• v.30
• /
• pp.251-261
• /
• 2017

Metal is a material that has exerted a lot of influence on the development of human cultures, and has closely connected with our life from the past to the present. Types of metal we have used from the prehistoric times are varied, and iron relics take the largest percentage of metal relics excavated in our country. The biggest threat to the existence of iron relics ranging from excavated relics to the ones that are transmitted is the process of corrosion, and physical removal has been used the most for removing corroded oxides. For details for removal of corrosion oxides, this thesis aimed to research on the chemical corrosion oxides remover that protects parent material of iron relics but treats corrosion oxides only. For safe and effective removal of corrosion oxides of iron relics, this study was conducted aiming at finding the possibility of and optimized composition for removal of iron relics corrosion oxides by manufacturing new acid, alkaline and neutral oxides removers and changing their composition variously, exploring the possibility by applying the agents to modern relics. The results of this study are as follows: First, the acid solution removed only some part of corrosive substance oxidized on the surface of metal specimen. Second, the application of each of alkaline and neutral solution resulted in remaining black-colored corrosive substance, but it was removed when the quantity of the solution and the duration of application are increased. Third, All the three solutions did not cause any damage to parent material in the course of application, and showed the result that they are capable of removing unstable oxide layer while protecting parent material and stable corrosive layer as the solutions would be able to deal with situation by a relic only through the control of concentration of solution and duration of application.

• The Korean Journal of Petroleum Geology
• /
• v.10 no.1_2 s.11
• /
• pp.10-17
• /
• 2004

The Doowoo-ri tidal flat in the southwestern Korean coast is a typical open-coast tidal flat which has no barriers in the offshore such as barrier island and sand bars. The difference of induced wave energy with seasons is affected directly on the distribution of surface sediment and the formation of sedimentary structures because the sedimentation by wind wave is relatively much important element in this open-coast tidal flat. This open-coast tidal flat can be classified into tidal beach, intertidal flat and lower mudflat according to the pattern of geomorphology and sediment type. The intertidal flat can be again divided into 3 types: sand flat, mixed flat and mud flat based on the primary sedimentary structure and sand/mud ratio. Doowoori tidal flat shows a seasonal change in the surface sedimentary facies based on sediment composition and primary sedimentary structure. The change is closely related to the direction and magnitude of monsoon wind and also to storm frequency. In winter and spring, when northwesterly wind is most dominant and strong and also storms are common, sand-flat facies is largely distributed on the intertidal flat, whereas mud-flat facies is most dominant during summer when weak southeasterly wind is common. In the fall season, mixed-flat facies is dominant on the flat. The Doowoori intertidal flat is covered by mud sediment which is ca. 20 cm in thickness in summer season. In winter season, surface sediment is changed from mud to sand because the summer mud is mostly eroded by strong wave action. Can-core peels in the intertidal flat show that parallel laminated mud or sand/mud and climbing ripple cross-laminated sandy silt are dominant on the upper intertidal flat $(0-1.3 {\cal}km)$ during summer season. On the other hand, on lower intertidal flat $(1.7-2.3 {\cal}km)$, dominant sedimentary facies is homogeneous mud. In winter, it is changed into parallel laminated and ripple cross-laminated sand facies.