• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.3 no.3
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• pp.189-196
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• 1999

The community structure, phytomass, and primary productivity in Thuja orientalis stands on a limestone area located in Maepo-up, Chungbuk province in Korea were estimated quantitatively. Seven species including a small proportion of Quercus dentata were identified in the tree layer, 26 species including Ulmus macrocarpa in the shrub layer, and 79 species including Carex lnceolata in the herb layer of the Thuja stands. The vertical distribution of the fine root phytomass exhibited a power functional decrease relative to the soil depth. The seasonal changes in the fine root phytomass at a soil depth of 5 cm were closely related to the pecipitation in the study area. The productivity of the stand of stems, branches, leaves, and roots were 10.72, 0.82, 0.45 and 6.46 ton DM. $ha^{-1}$ .$yr^{-1}$, respectively. The Thuja stand had a high foliage(25%) and low rate of production per unit of foliage. The annual turnover rate of the fine roots int he Thuja stand was 6.71 $yr^{-1}$. The net primary production of the overstory including the understory was estimated at 19.48 ton DM.$ha^{-1}$.$yr^{-1}$ including an underground section of 6.46 ton DM.$ha^{-1}$.$yr^{-1}$(33%). The allocation ratio of net production to root was lower in the limestone Thuja communities than at the nearby non-limestone ones, whereas the production efficiency to leaf weight was higher in the limestone communities. These results would seem to indicate that the limited production capacity is due to the calcium toxicity and low availability of iron and phosphorus in a limestone soil with a high pH, calcium, and bicarbonate content with a strategy for survival in a hostile habitat.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.518-518
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• 2016

Agriculture is the lifeblood of the economy in Ghana, employs about 42% of the population work force and accounts for 30% of the Gross Domestic Product (GDP). Corn (maize) is the major cereal crop grown as staple food under rain fed conditions, covers over 92% of the total agricultural area, and contributes 54% of the caloric intake. Issues of hunger and food insecurity for the entire nation are associated with corn scarcity and low production. The climate changes are expected to affect corn production in Ghana. This study evaluated variations of corn yields based on different climate conditions of rain-fed area in the Dangbe East District of Ghana. AquaCrop model has been used to simulate corn growing cycles in study area for this purpose. The main goal for this study was to predict yield of corn using selected climatic parameters from 1992 to 2013 using different climate scenarios. The Model was calibrated and validated using observed field data, and the simulated grain yields matched well with observed values for the season under production giving an R squared (R2)of 0.93 and Nash-Sutcliff Error(NSE) of 0.21. Study results showed that rainfall reduction in the range of -5% to -20% would reduce the yield from 1.315ton/ha to 0.421ton/ha (-21. 3%) whereas increasing temperature from 1% to 7% would result in the maximum yield reduction of -20.6% (1.315 to 1.09 ton/ha.). On the other hand, increasing rainfall from 5-20% resulted in yield increment of 68% (1.315-2.209 ton/ha) and decreasing temperature produce 7% increase in yield ( 1.315 to 1.401ton/ha). These results provide useful information to adopt strategies by the Government of Ghana and farmers for improving national food security under climate change.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.705-708
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• 2009

For the Gas hydrate Research and Development in Korea, the prospect area I & II was surveyed and drilled during the first phase. At the result, we succeeded to discovering gas hydrate real sample at BSR reflection and vent structure. This expedition processing contributes to developing the offshore seismic survey technologies and data processing of Korea. But Korean gas hydrate test production research, in spite of activating test production at other countries, is such a limitation about technician, GH production technologies and E&P processing. First of all, there is no exist in Korea to application site for the their production research results. In this paper, we have studied the gas hydrate reservoir selection technics of the DOE & BPXA for the ANS test production. And this result will helpful to preparation of gas hydrate test production in Korea.

• Journal of the Korea Safety Management & Science
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• v.11 no.4
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• pp.193-199
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• 2009

Recently, an industrial production-distribution planning problem has been widely investigated in Supply Chain Management(SCM). One of the key issues in the current SCM research area is reverse logistics network. This study have developed a simulation model for the reverse logistics network. The simulation model analysis reverse logistics network issues such as inventory policy, manufacturing policy, transportation mode, warehouse assignment, supplier assignment. Computational experiments using commercial simulation tool ARENA show that the real problems. The model can be used to decide an appropriate production-distribution planning problem in the research area.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.223-226
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• 2005

For $CO_2-free$ hydrogen production and better utilization of the produced carbon, catalytic decomposition of methane over rubber-grade carbon blacks manufactured from coal tar was carried out. The catalytic activities of several domestic carbon blacks were compared. A pelletized carbon black exhibited considerably lower activity and activation energy than the fluffy( loose) carbon black of the same grade. This difference is considered due to the binder that was added during pelletization. For pelletized carbon blacks, a tendency was observed that the activity per unit mass of catalyst increased with the specific surface area of the carbon black. Another tendency was also observed that the activation energy increased with the primary particle size or decrease of the specific surface area.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2003.05a
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• pp.192-195
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• 2003

Digital art brought about first in 19s6s by Laposky Ben and became a area of new art. Also, digital art gives new possibility to systematize concept and actions in whole art and to invent some media which can carry the sense experience with space. However, reason that has often cynical meaning is appearing in preconception which technology falls off humanity. Because of digital technology, space production can become dreary, so it is necessary to sensuous production that connects digital with space which contains meaning of interior space. The purpose of this study is to find out spare which can be communicated from viewpoint of interaction through spatial substitution and characteristics of various expression production which have been involved newly in digital art area.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.1
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• pp.26-32
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• 2001

An ecpert system for rotationally symmetric deep drawing products has been developed. The application for non-axisymmetric components, however, has not been reported yet. This study construsctus and expert system for non-axisymmetric motor frame which shape is classified into ellipse in deep draqing process and investigates process sequence design with elliptical shape. The developed system consists of four modules. The first is recognition of calculate surface area for non-axisymmetric products. The third is blank design module the creates an oval-shaped blank with the same surface area. The fourth is a processplanning module based on production rules that play the best important roles in an expert system for manufacturing .The production rules are generated and upgraded by interviewing field engineers. Especially, drawing coefficient, punch and die radii for elliptical shape products are considered as main design parameters. The constructed system for elliptical deep drawing product would be very useful to reduce lead time and improve accuracy for products.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.73-76
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• 2005

Recently, the demand for the Floating, Production, Storage, and Offloading facility (FPSO) which has some economic and technical advantages, has increased in offshore oil production areas. FPSO vessel dose not have self-propulsion system, but has additional facilities for oil production and positioning system. Main noise sources such as gas turbines, compressors, and pumps, are located on top of the hull (Topside area). In general, the noise regulation for the offshore structure is severer than that of the cargo ship and acceptable noise limit of cabin is specified as 45 dB(A). This paper describes the noise characteristics and the countermeasures for FPSO Topside area through investigation of noise analysis and site measurement results. Proper countermeasures, considering the characteristics of sources and receiver spaces, were applied from the noise prediction and various measurement results. Finally, this ship was successfully delivered with excellent noise properties.

• Carbon letters
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• v.13 no.1
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• pp.48-50
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• 2012

Mass production of graphene-based materials, which have high specific surface area, is of importance for industrial applications. Herein, we report on a facile approach to produce thermally modified graphene oxide (TMG) in large quantities. We performed this experiment with a hot plate under environments that have relatively low temperature and no using inert gas. TMG materials showed a high specific surface area (430 $m^2g^{-1}$). Successful reduction was confirmed by elemental analysis, X-ray photoelectron spectroscopy, thermogravimetic analysis, and X-ray diffraction. The resulting materials might be useful for various applications such as in rechargeable batteries, as hydrogen storage materials, as nano-fillers in composites, in ultracapacitors, and in chemical/bio sensors.

• Nano
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• v.13 no.12
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• pp.1850143.1-1850143.9
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• 2018

Natural biotemplates - such as bacteria, fungi and viruses - are used in nanostructured metal oxide production. The pollen can be found abundantly in nature, and their microcapsules can be easily isolated from the pollen by chemical treatments. To date, pollen microcapsules are mostly used as drug carriers and catalytic agent templates. In the present study, nanoporous-structured nickel oxide is produced using Pistachio pollen microcapsules. The raw pollen, chemically treated pollen and metal-coated pollen were characterized using scanning electron microscopy, Brunauer-Emmett-Teller (BET) surface area analysis, thermogravimetric analysis (TGA), differential thermal analysis (DTA) and X-ray diffraction (XRD) techniques. The natural Pistachio pollen which were procured from Gaziantep, Turkey, are spherical, with a diameter of approximately $23{\mu}m$. The maximum surface area obtained for nickel oxide-coated microcapsules is $228.82m^2/g$. This result shows that Pistachio pollen are an excellent candidate for the production of porous nanostructured materials for supercapacitor electrodes.