• Journal of the speleological society of Korea
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• no.7
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• pp.15-24
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• 1998

Conservation is the optimum sustained use of natural resources; therefore, cave conservation must provide not only for the protection of the character, decoration and biota of caves, but also for the means whereby people might enjoy and understand the caves that are their heritage. A cave is a natural subterranean cavity into which a man can enter to a point where daylight cannot be seen. Caves are not only interesting physical entities that provide distinctive sensory and perceptual experiences and invoke a variety of responses, but they also provide unique opportunities for scientific study. Speleology is the study of caves, and in New Zealand it attracts workers from many disciplines of the universities and government research establishments.(omitted)

• Journal of the Speleological Society of Korea
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• no.78
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• pp.33-41
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• 2007

Alpine caves, subterranean passages, are extensively controlled by folds and faults. Caves of the regions demonstrate a significant dip of the passages due to the structural deformations. There are many vertical voids and shaft. Speleo-scapes in the internal caves are various. Calcite formations show the water table alternations which indicate the uplifting and erosional base level droppings during at least the Quaternary. Around cave entrenches there are remnants of the Fluvial terraces on the middle of the hills. These relationship between cave locations and terraces will generate a key to the Plestocene history of the south Korean peninsula. Hence, the Korean karst is turned as "the overburden alpine karst".

• Journal of the Korean Wood Science and Technology
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• v.46 no.2
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• pp.155-165
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• 2018

The objective of the research was to evaluate the effect of particle pre-treatment on physical, mechanical, and durability of jatropha fruit hulls (JFH) particleboard. The pre-treatments included were immersing in cold water, hot water, and acetic acid solution. After each treatment, the particles were dried up to 3% moisture content. Urea-formaldehyde (UF) resin was used to fabricate particleboards with board size, thickness and density target of 25 cm by 25 cm, 0.80 cm, and $0.70g/cm^3$, respectively. Board pressed at $130^{\circ}C$ for 10 minutes, and $25kg/cm^2$ pressure. The evaluation of particleboard followed the JIS A 5908-2003. Whilist their resistance to subterranean termite test (mass loss, mortality, antifeedant value and feeding rate) refers to the Indonesian standard (SNI 01.7207-2006). The physical and mechanical properties of particleboards showed that all pre-treatments decreased the pH of particles. Overall, all particle immersing treatments resulted of better physical and mechanical properties of particleboard than those of untreated ones. The acetic acid treatment resulted the best physical and mechanical properties of particleboard. Based on the mass loss of JFH particleboard, hot water and acetic acid treated particleboards were classified into weak resistance to subterranean attack. The other two treatments were classified into very weak resistance. Hot water treated particleboard provided the highest mortality and antifeedant as much as 87.40% and 34.20%, respectively. Based on antifeedant classification, hot water treated particleboards were classified into moderately strong resistance, while other treatments were categorized into weak resistance. The lowest feeding rate value ($45.30{\mu}g/termite/day$) was attained by hot water treatment.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.372-380
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• 2012

This study was conducted to determine the contents of astragalosides in Astragalus membranaceus. The total astragaloside content ($1701{\mu}g\;g^{-1}$) of 2 year-cultivated astragalus was the highest among the variously cultivated astragalus plants. Upon an increase in cultivation time, the average value of the total astragaloside content decreased (from $1650{\mu}g\;g^{-1}$ to $645{\mu}g\;g^{-1}$). Especially, the content of astragaloside decreased rapidly. Comparison between the top and subterranean parts of harvested astragalus plants showed that as the cultivation time increased, the astragaloside content of the top part decreased. On the other hand, the subterranean part demonstrated the opposite pattern. The astragaloside content of the top root increased compared to that in the lateral root (from $1.9{\mu}g\;g^{-1}$ to $33.4{\mu}g\;g^{-1}$). Further, the content of astragaloside increased in the top root as the cultivation time increased.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.199-210
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• 2012

In this study, a pull-out strength increasement of grasses was tested in field and the relationship between a weight of root and pull-out strength was established. The tested grasses were commmon reed, reed and sedge which were cultivated by mat-type like turf and used for revegetation of bank. The shear stress of soil at a section can be discribed as a function of root area and pull-out strength, therefore the result of this study will be used as a foundational data for reinforcing the shear stress of the revegetated bank. The heavier weight of root increased, the stronger shear stress was for all grasses. But the relationship between the weight and the shear stress were different by a kind of grass. The difference between common reed, sedge and reed is due to difference of growth and propagation. A reed propagates by subterranean stem and a root weight and pull-out strength are linearly increased by root and growth of subterranean stem.

• Korean Journal of Food Science and Technology
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• v.13 no.3
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• pp.247-252
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• 1981

As a primary study for the improvement of yield and preference of soybean sprouts, the water absorption rates by soaking and the growing characteristics of sprouts were investigated. When the soybeans were soaked in subterranean water at $18^{\circ}C$ for 4 hours, water absorption rates by weight percent of soybeans were ranged $167.0{\sim}194.5%$, and it means that the absorption rates do not greatly influence its germination rates. The yield of soybean sprout whose common name is Guryetai and of the sprout treated with 1 ppm Gibberellin marked the highest value, 837% and 585%, respectively. In case of industrial cultivation of soybean sprout, it is supposed that sprinkling with subterranean water is good for prevention of deterioration by growth of microorganisms and respiratory heat.

• Korean Journal of Medicinal Crop Science
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• v.20 no.6
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• pp.447-453
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• 2012

This study was conducted to determine the contents of phenolic compounds and astragalosides in Astragalus membranaceus. Between the phenolic compound groups, flavonoids compounds (51.13%) had higher average concentrations than the phenolic acids groups. Among the 30 phenolic compounds, quercetin ($353.11{\mu}g\;g^{-1}$) provided the highest concentrations. According to different cultivation year, 3-year-cultivated Astragalus ($2612.57{\mu}g\;g^{-1}$) showed the highest concentrations of phenolic compounds. According to different harvest days, 6/5 harvesting Astragalus ($2615.80{\mu}g\;g^{-1}$) showed the highest concentrations of phenolic acids. Comparison between the top and subterranean parts of harvested Astragalus plants cultivated for 2 years, 3 years, and 5 years showed big difference of total phenolic compounds in concentrations. Further, the top part had higher amounts of the total phenolic compounds than the subterranean part among all Astragalus. This tendency was similar to those of the top root and lateral root. The concentration of the phenolic compounds in the top root was higher than that of the lateral root.

• Journal of architectural history
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• v.30 no.4
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• pp.67-78
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• 2021

This is a study on the structural changes of the tumulus and causes setting up a Sabangseok at the front of the tumulus at the royal tomb in the JoSeon dynasty, during the 17th~18th centuries. The Sabangseok was first used in the tumulus of Mongnueng(穆陵) in 1630. It is a multipurpose stone for boundary, foundation of the tumulus and blocking the sliding down of the tumulus. It was set up, when constructing a Yeongneung(寧陵) in 1673. But the vast spill of tumulus soil made it improve structure of the Sabangseok. Consequently, when the Yeongneung was re-constructed, the structure of the tumulus was fundamentally improved. The soil layer on the lime of the subterranean chamber became eliminated. Also the lime of the tumulus and the lime of the subterranean chamber became a united structure. The Sabangseok was still used until 1757 on account of precedents, although it would become unnecessary after structural improvement of the tumulus in 1673. In 1757, Yeongjo(The 21th monarch of the Joseon Dynasty) commanded repeal on the use of the Sabangseok, when constructing the Hongneung(tomb of Queen Jeongseong). The decision and discussions about abolition on the use of the Sabangseok was recorded in Gukjosangryebopyeon.

• Journal of the Korean Wood Science and Technology
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• v.52 no.1
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• pp.70-86
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• 2024

Termites are a serious threat to wood-based products in Indonesia. This study investigated the termite resistant property of glulam made from polystyrene-modified wood. Three tropical fast-growing wood species, namely mangium (Acacia mangium), manii (Maesopsis eminii), and rubberwood (Hevea brasiliensis), were prepared for flat-sawn laminae. After getting air-dried condition, the laminae were impregnated with polystyrene using potassium peroxydisulphate as a catalyst followed by polymerization at 80℃. Polystyrene-impregnated and control glued-laminated lumbers (glulams) were manufactured, and solid wood was provided. Three wood species and three wood products with six replicates were exposed in a field in Bogor, Indonesia, for four months, and before the tests, their density and moisture content were measured. At the end of the field tests, the weight loss and protection levels of each test sample were determined. A completely randomized factorial design was used for data analysis. The weight percentage gains for mangium, manii, and rubberwood were 22.30%, 18.22%, and 10.44%, respectively. The results showed that manii belonged to low-density wood, whereas the other two woods were medium-density wood, and the moisture content was the ambient moisture content, typical of the Bogor area. Regarding weight loss and protection level, mangium was the most durable against subterranean termite attacks, followed by rubberwood and manii. Among the wood products, the polystyrene-impregnated glulam presented the highest durability, followed by the control glulam and solid wood. Therefore, mangium and rubberwood polystyrene-impregnated glulams are recommended for future product development.

• Korean Institute of Interior Design Journal
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• no.10
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• pp.28-33
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• 1997

The primary purpose of this thesis is to offer users for the better surroundings in planning subway wall design through analyzing the Wall Environmental Design at Subway Statiov. As the urban circumstances were developed by the economic growth, the new city plan, re-development evoked the radical changes in the urban circumstances. In processing the industrialization and urban surroundings. This range has enlargened and provided the localism, the function, the purpose with the visual informations. The method of this paper was the spot survey simultaneously the photographing of the mould's size. theme, colour, material, compossitiov. In conclusion, concerning about the artificial and subterranean space, the Wall Environmental Design at Subway Station needs more practial approach in the using the space.