• Korean Journal of Plant Taxonomy
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• v.48 no.3
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• pp.153-162
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• 2018

Lespedeza maximowiczii C. K. Schneid. (Fabaceae) is a deciduous shrub which is known to be distributed in the temperate forests of China, Korea and on Tsushima Island of Japan. Due to severe morphological variations within species, numerous examinations have been conducted for Korean L. maximowiczii. However, the morphology of Chinese plants has not been studied as thoroughly, despite doubts about their taxonomy. To clarify this taxonomic issue, we investigated morphological characters and undertook a Bayesian clustering analysis with microsatellite markers. The morphological and genetic traits of Chinese individuals varied considerably from those of typical L. maximowiczii growing in Korea. For example, petals of the former had a different shape and bore long claws, while the calyx lobes were diverged above the middle and the upper surface of the leaflet was pubescent. Their terete buds and spirally arranged bud scales were distinct from those within the series/section Heterolespedeza, which includes L. maximowiczii. Our Bayesian clustering analysis additionally included L. buergeri as an outgroup. Those results indicated that the Chinese samples clustered into a lineage separated from L. maximowiczii (optimum cluster, K = 2), despite the fact that the latter is grouped into the same lineage with L. buergeri. Therefore, we treat those Chinese plants as a new species with the name L. pseudomaximowiczii.

• Structural Engineering and Mechanics
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• v.28 no.1
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• pp.19-38
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• 2008

A general solution to the field equations of homogeneous isotropic generalized thermoelastic diffusion with two relaxation times (Green and Lindsay theory) has been obtained using the Fourier transform. Assuming the disturbances to be harmonically time.dependent, the transformed solution is obtained in the frequency domain. The application of a time harmonic concentrated and distributed loads have been considered to show the utility of the solution obtained. The transformed components of displacement, stress, temperature distribution and chemical potential distribution are inverted numerically, using a numerical inversion technique. Effect of diffusion on the resulting expressions have been depicted graphically for Green and Lindsay (G-L) and coupled (C-T) theories of thermoelasticity.

• Journal of Ocean Engineering and Technology
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• v.9 no.2
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• pp.71-74
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• 1995

A numerical model capable of simulating a 2-D airfoil flying over in the vicinity of the waves is discussed. Instead of treating the problem as a heaving oscillation one above the rigid flat wall, sources are distributed on the prescribed wave profile. The wave deformation due to the airfoil is assumed to be negligible and treated as a rigid undulated wall. The source and vortex are distributed on the surface of the foil. It is found that the variation of $C_L$ with wave steepness in severe and that the lift variation due to waves decreases as the wing height above the water surface increases.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.277-278
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• 2006

This paper presents circuit models and control algorithms of distributed generation system(DGS) which consists of Z-type converter and PWM inverter Z-type converter which employs both the L and C passive components and shoot-through zero vectors instead of the conventional DC/DC converter in order to step up DC-link voltage. Discrete time sliding mode control with the asymptotic observer is used for current control.

• Electronics and Telecommunications Trends
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• v.30 no.3
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• pp.105-114
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• 2015

다양한 규모와 형태의 클라우드 인프라를 보다 쉽게 구축하고 관리할 수 있는 공개 소프트웨어 기반의 클라우드 운영체제인 OpenStack은 Icehouse 배포판 이후부터 새로운 기능의 추가 못지 않게 안정성 확보에 주력하면서 엔터프라이즈 클라우드를 위한 기본 기능이 성숙 단계에 진입하고 있는 것으로 판단된다. 다만, 클라우드 네트워킹을 담당하는 Neutron의 경우 네트워크 기능 가상화(NFV: Network Functions Virtualisation) 기술의 출현으로 더욱 많은 관심을 받고 있으나 아직 기술의 복잡성, 성능 및 고가용성 등에 대한 우려 등으로 폭넓게 활용되지 못하고 있다. 이에 따라 Neutron 프로젝트에서는 분산 라우터(DVR : Distributed Virtual Router) 기술과 L3(Layer 3) 고가용성 기술 등을 새롭게 선보이게 되었다. 본고에서는 지난 10월, 10번째로 발표된 Juno 배포판의 특징을 간략히 살펴본 다음, Neutron 프로젝트에서 꾸준히 요구되어 왔던 분산 라우터(DVR) 기술에 대한 개발 현황과 특징 그리고 동작 방식에 대해 정리한다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.20-20
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• 2019

Sedge family is second largest family in the Korean flora with more than 240 taxa, following Aster family (about 300 taxa). Although high species diversity, a very limited number of taxa has been utilized for ethnobotanical usages. In the study, previous researches on Cyperaceae ethnobotanical information are documented and analyzed for future research directions on the taxa. A total number of seven taxa has been used for medicinal, food, and material purposes: Carex boottiana Hook. & Arn., Cyperus amuricus Maxim., Cyperus esculentus L., Cyperus exaltatus Retz., Cyperus rotundus L., Eleocharis kuroguwai Ohwi, and Bolboschoenus maritimus (L.) Palla. Underground parts such as tubers are used with medicinal purpose, and aboveground portions such as leaves and stems provide materials for various tools and foods for people and animals. They are all native to Korea, except C. esculentus, which is introduced from Mediterranean areas for anti-erosion materials. The ethnobotanical value of C. esculentus has been well recognized from ancient times, for example, starch grains in USA (excavations at the Mashantucket Pequot Reservation) and Tiger nut milk (Horchata de chufa in Spain). Among material sources, C. exaltatus has a long history in the Korean peninsula from Three Kingdoms of Korea (57 BC~668 AD). C. rotundus is distributed widely in Asia, Africa, Europe, and America, and utilized for medicines, food, and materials. In addition, Eleocharis kuroguwai is only one taxon utilized for ethnobotanical uses among fifteen Eleocharis Korean native species. The number of species with ethnobotanical uses is small in sedge family, but the family has long been utilized accompanying long human history. Cyperus papyrus L., the source of papyrus paper (Egypt in the Nile Delta), is also a member of sedge family. Sedge family has contributed to human societies in various aspects but, the cultural, botanical, ecological values of family members have been underestimated.

• Journal of Mushroom
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• v.21 no.1
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• pp.8-14
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• 2023

This study aimed to verify the whitening effect of Cordyceps militaris, which is distributed in several countries worldwide, including Korea, Japan, and China, and has various medical effects. To screen the efficacy of C. militaris, the inhibitory activity of tyrosinase, which was 66% at a concentration of 1 mg/mL, was measured. Thereafter, the survival rate of melanoma cells was measured, and cell experiments were conducted at a concentration of 90% or more in which C. militaris was not toxic to cells. After measuring the inhibitory effect of TRP-1, TRP-2, tyrosinase protein, and mRNA expression, which are factors influencing melanin synthesis, C. militaris was found to decrease in all factors, with an expression level that was significantly lower compared to quercetin. This confirmed that C. militaris stimulated with LED has excellent whitening activity and can be used as a functional whitening cosmetics material.

• Journal of Life Science
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• v.29 no.2
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• pp.209-214
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• 2019

Sargassum horneri (Turner) C. Agardh is a marine brown algae widely distributed in the North Pacific Ocean. It is known for its anti-inflammatory and anti-atopic effects. In this study, we determined the effects of ethanol extract of Sargassum horneri (Turner) C. Agardh (EESH) on anti-obesity activities in 3T3-L1 preadipocytes. Our results indicated that treatment with EESH decreased the differentiation of 3T3-L1 preadipocytes in a dose-dependent manner, as confirmed by a decrease in lipid droplet content observed by oil red O staining. The concentrations of cellular triglycerides were also reduced in 3T3-L1 cells after treatment with EESH. Triglyceride content was inhibited by 13%, 16%, and 23% after treatment with 250, 500, and $1,000{\mu}g/ml$ of EESH in 3T3-L1 cells, respectively. Western blotting analysis showed that EESH suppressed adipogenic transcription factor expression in a dose dependent manner. Specifically, it suppressed cytidine-cytidine-adinosine-adenosine-thymidine (CCAAT) /enhancer binding proteins $(C/EBP){\alpha}$, $C/EBP{\beta}$ and peroxisome proliferator-activated receptor $(PPAR){\gamma}$. This indicated that EESH could control the expression of adipogenic transcription factors and inhibit the differentiation of adipocytes. Taken together, these findings demonstrated that EESH showed anti-obesity effects and could have potential uses in the field of nutraceuticals.

• Journal of Species Research
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• v.3 no.1
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• pp.7-16
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• 2014

Many species of Lymantria are important forestry pests, including L. dispar which is well known distributed from Asia to North America as an invasive species. Like of most other genera of moths, the systematic of this genus is still in dispute, especially on the monophyly and the relationship within this genus due to the fact that genus is very large and varied. This genus was morphologically defined only by a single aphomorphy. To clarify the monophyly of the genus Lymantria, to reveal the phylogenetic relationship among the Indonesian species, and to establish the genetic characters of Indonesian Lymantria, we analyzed 9 species of Indonesian Lymantria involving 33 other species distributed around the world based on nucleotide sequence variation across a 516-bp region in the CO I gene. The results showed that the base composition of this region was a high A+T biased (C: 0.3333). The results also showed that the monophyly of Lymantria was not supported by bootstrap tests at any tree building methods. Indonesian species was distributed into four different groups but the relationship among them was still in dispute. It indicates that relationships among the basal nodes (groups) proposed here were least valid due to the fact that the number of species may not be enough to represent the real number of species in the nature. Moreover CO I gene sequences alone were not able to resolve their relationships at the basal nodes. More investigations were needed by including more species and other genes that the more conserved.

• Journal of Environmental Science International
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• v.26 no.11
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• pp.1285-1295
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• 2017

Chrysanthemum boreale Makino is widely distributed in Korea, China, Japan and Southeast Asian countries. C. boreale is one of the herbs used for treating various inflammatory diseases in oriental medicine. The present study was conducted to identify biologically active compounds from the leaves and stems of C. boreale. We isolated two sesquiterpene sactones from the leaves and stems of C. boreale using silica gel column chromatography and recyclic high perfomance liquid chromatography. The lactones were characterized by their spectroscopic data (NMR, IR, MASS). These compounds were subjected to Farnesyl Protein Transferase (FPTase) inhibition, Nitric Oxide (NO) release inhibition and apoptosis inhibition. The structur of the following isolated compound were elucidated 8,10-${\small{O}$-Acetyl-2-methoxy-10-hydroxy-3,11(13)-guaiadiene-12,6-olide and 4,10-dihydroxy-8-${\small{O}$-Acetyl-2,11(13)-guaiadiene-12,6-olide. In the NO release inhibition assay, compound 2 showed strong activities, with an $IC_{50}$ value of $7{\mu}g/mL$, whereas compound 1 did not exhibit significant activity with an $IC_{50}$ value of over $14{\mu}g/mL$ against murine macrophage.