• Smart Structures and Systems
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• v.8 no.1
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• pp.1-15
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• 2011

Cerebral aneurysm is common lesion among adult population. Current methods for treating the disease have several limitations. Inspired by fern leaves, we have developed a new stent, called leaf stent, which can provide a tailored coverage at the neck of an aneurysm and thus prevent the blood from entering the aneurysm. It alone can be used to treat the cerebral aneurysm and therefore overcomes problems existing in current treating methods. The paper focuses on the numerical simulation of the leaf stents. The mechanical behaviour of the stent in various designs has been investigated using the finite element method. It has been found that certain designs provide adequate radial force and have excellent longitudinal flexibility. The performance of certain leaf stents is comparable and even superior to those of the commercially available cerebral stents such as the Neuroform stent and the Enterprise stent, commonly used for stent assisted coiling, while at the same time, providing sufficient coverage to isolate the aneurysm without using coils.

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.76-86
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• 2018

Turfgrass species were evaluated for their rooting and foliar characteristics, and their interaction with the soil. The rooting system was divided into three compartments, one above another, such that the top and bottom compartments of the root system could be supplied with a nutrient deprived solution. Exposure of parts of the roots to nitrate deprivation caused a localised retardation of root initiation and extension, compared with zones receiving the full supply of nutrients. This resulted in considerable modification to root form, coupled with a significant depression in foliar growth. The extension of roots was the least affected by the deprivation of potassium. Phosphate and calcium deprivations gave rise to similar responses in root and foliar formation. Results from this study showed that external concentrations of nitrogen, phosphorus, potassium and calcium are required by the root system in varying amounts for optimal growth of roots. Turfgrass coverage and turf quality ratings further reinforced these findings. No significant difference was observed between the different grasses examined here. All three species responded similarly to the deprivation of the various nutrients. Results from this study confirmed that targeted fertilization programs are beneficial and can help reduce cost, chemical usage and prevent leachate and contamination.

• Journal of the Microelectronics and Packaging Society
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• v.20 no.4
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• pp.69-74
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• 2013

In this paper, the impact of integrating large number of I/O (Input-Output) and Core power Delivery Network (PDN) on a 6 layers Flip-Chip Ball Grid Array (FCBGA) package is investigated. The impact of core induced supply noise on high-speed I/O interfaces, and high-speed I/O interface's supply noise coupling to adjacent high-speed I/O interfaces' jitter impact are studied. Concurrent stress validation software is used to induce SSO noise on each individual I/O interfaces; and at the same time; periodic noise is introduced from Core PDN into the I/O PDN domain. In order to have the maximum coupling impact, a prototype package is designed to merge the I/O and Core PDN as one while impact on jitter on each I/O interfaces are investigated. In order to understand the impact of the Core to I/O and I/O to I/O noise, the on-die noise measurements were measured and results were compared with the original PDN where each I/O and Core PDN are standalone and isolated are used as a benchmark.

• Journal of Ecology and Environment
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• v.37 no.2
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• pp.61-67
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• 2014

Mankyua chejuense is a native endangered plant distributed only in Gotzawal, a forested wetland, in Jeju Province, Korea. In order to determine the optimal environmental conditions for the growth and development of M. chejuense, we investigated the above- and below-ground growth responses and survival rate to various soil texture (sand and clay), water regimes (flooding and non-flooding), and $CO_2+T$ (ambient and elevated) conditions. All of the treatments had significant effects on aboveground growth parameters, while only the water regime and $CO_2+T$ treatments influenced belowground growth. The survival rate of M. chejuense was about twice higher under the sand, non-flooding and elevated $CO_2+T$ conditions than clay, flooding and ambient $CO_2+T$ conditions. These results indicate that M. chejuense grows in well-drained sandy soil conditions and elevated $CO_2$ concentration and temperature situations. Thus, there is a need to maintain M. chejuense under constant non-flooding soil conditions by implementing appropriate soil drainage strategies.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.374-380
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• 2006

With the aim of inducing mutation in fern Cyrtomium caryoptideum var. coreanum, rhizome segments of In vitro-grown cultures were treated with chemical mutagens such as EMS, NMU and colchicine. Based on regeneration ratios, sensitivities for each treatments were assessed and also optimum treatment condition of each mutagens was explored. Optimum concentration for EMS treatment was considered to be 20 to 50mM and for NMU 5 to 10mM. NMU was found to be more effective in inducing chlorophyll and morphological variations than EMS. The RAPD were performed to check the genetic modification of phenotypical variants. As a result, polymorphic DNA band patterns between wild type and variants were observed by two 10-mer primers.

• Korean Journal of Plant Taxonomy
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• v.46 no.3
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• pp.283-287
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• 2016

Field work conducted in Natma Taung National Park, Chin State, Myanmar, in 2015 to make a checklist of lycophytes and ferns resulted in the discovery of four fern species not previously recorded in the flora of Myanmar. All occur in other countries in southeastern Asia, and in other tropical areas. The species are as follows: Adiantum monochlamys (Adiantaceae), Ctenitis decurrentipinnata (Dryopteridaceae), Pteris tripartita, and Paragymnopteris vestita (Pteridaceae). These findings will enable us to update the checklist of ferns of Myanmar.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.6 no.2
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• pp.192-196
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• 2003

Angiodysplasia is the most common vascular abnormality of the gastrointestinal tract and probably the most frequent cause of recurrent lower intestinal bleeding in otherwise healthy elderly patients. Also, it is an important cause of hemorrhage in chronic renal failure observed in up to 19~32% of patients. Bleeding due to gastric angiodysplasia is treated by various endoscopic approaches, including argon and Nd : YAG laser photocoagulation, monopolar or bipolar electrocoagulation, heater probe, injection sclerotherapy, band ligation or hemoclipping. A 15-year-old boy, who had undergone hemodialysis for chronic renal failure for about 10 years, was admitted due to melena and progressive anemia. A gastroduodenoscopy revealed a cherry red and fern-like lesion with oozing on the posterior wall at junction of gastric body and fundus. Endoscopic hemoclipping therapy was performed. However, melena recurred four days later. Argon plasma coagulation and hemoclipping therapy were performed again. Since then, no recurrence of bleeding has been observed.

• The Journal of the Korea Contents Association
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• v.7 no.12
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• pp.322-332
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• 2007

We consider a deformation method suitable for fractal. In IFS fractal, the position of a point is characterized by its code as well as by its coordinates. Code has a meaning of address for fractal. If we move a point by changing its code, the resulting movement shows fractal behavior. We propose three deformation methods based on code information. For the deformation vector of a point in fractal, 1) we use the vector of a given vector field at the point obtained by code transformation, 2) we use the vector constructed by adding predefined displacement vectors according to the code information of the point. Both methods show a fractal-like character as well as an ordinary continuous deformation character. Also, 3) we can deform fern-fractal more naturally by restricting its deforming region using code form.

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.88-94
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• 2016

Vehicular traffic on turf results in loss of green cover due to direct tearing of shoots and indirect long-term soil compaction. Protection of turfgrass crowns from wear could increase the ability of turf to recover from heavy traffic. Plastic turfpavers have been installed in trafficked areas to reduce soil compaction and to protect turfgrass crowns from wear. The objectives of this study were to evaluate traffic performance of turfgrasses (Zoysia matrella and Axonopus compressus) and soil mixture (high, medium and low sand mix) combinations on turf-paver complex. The traffic performance of turf and recovery was evaluated based on percent green cover determined by digital image analysis and spectral reflectance responses by NDVI-meter. Bulk density cores indicated significant increase in soil compaction from medium and low sand mixtures compared to high sand mixture. Higher reduction of percent green cover was observed from A. compressus (30-40%) than Z. matrella (10-20%) across soil mixtures. Both turf species displayed higher wear tolerance when established on higher sand (>50% sand) than low sand mixture. Positive turf recovery was also supported by complementary spectral responses. Establishment of Zoysia matrella turf on turfpaver complex using high sand mixture will result in improved wear tolerance.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.565-571
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• 2008

In the course of execution for Inventories and Management of Plant Resources of Korea, We found new habitats of 4 plant species which distribution ranges are obscure and/or extremely restricted. A subtropical fern distributed in Jeju-do, Woodwardia japonica (L. f.) Sm., was found in Mt. Gambang-san of Hampyeong-gun, Jeollanam-do. A saprophytic orchid, Galeola septentrionalis Reichb., was found in Mt. Ggachi-bong of Boseong-gun, Jeollanam-do. Peristrophe japonica (Thunb.) Bremek., known in Jeollanam-do, was newly found in Mt. Mudeung-san of Gwangju-si. Viburnum furcatum Blume mainly distributed in Jeju-do and Ulleung-do was found in Mt. Jabyeong-san of Gangneung-si, Gangwon-do.