• 전자통신동향분석
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• 제36권2호
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• pp.83-92
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• 2021

5G networks are rapidly expanding. Simultaneously, the need for a testbed-not a commercial network-is increasing to verify aspects such as 5G network security vulnerabilities. Open-source projects in 4G networks already exist and are implemented similarly in commercial networks. Due to the compatibilty between 5G and 4G networks, 5G networks are being developed and implemented as open-source projects on the basis of 4G networks. In this study, we review the development trends of 5G open-source projects and simulators that can be used for 5G research.

• 전자통신동향분석
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• 제37권3호
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• pp.1-10
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• 2022

Traditional centralized radio access network architecture used for 4G is based on Option 8, a functional split between PHY and RF. This option is commonly used with a fronthaul interface based on common public radio interface (CPRI) specifications; however, the increased data rates in 5G make this option impractical because of the fronthaul interface's high bandwidth requirement. Since CPRI specifications have many vendor-specific options, achieving multi-vendor interoperability becomes challenging. Open RAN (O-RAN) Alliance is developing novel open fronthaul interface specifications based on the functional split Option 7-2x, one of the intra-PHY split options, to relax the bandwidth requirement of the fronthaul interface and achieve multi-vendor interoperability. This article provides a brief overview of the various functional split options for 5G fronthaul that have been reported so far and existing fronthaul technologies. Further, the technological trends in the 5G open fronthaul interface is discussed, focusing on the O-RAN Alliance specifications under standardization.

• 기술혁신학회지
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• 제15권1호
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• pp.1-27
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• 2012

성공적인 개방형 혁신을 위해서는 조직 내부 기술 혹은 개발 전략과 함께 외부 자원을 동시에 고려하는 기술기획 도구가 필요하다. 본 연구는 개방형 혁신을 위한 조직 혹은 기업 내외부 자원 활용의 기획 수립과 수행을 위한 개방형 로드맵(open roadmap)을 제안한다. 개방형 로드맵은 내향적 그리고 외향적 개방형 혁신을 체계적으로 관리하고 계획하기 위해 사용된다. 또한 내향적, 외향적 혁신과 혁신 원천을 고려하여 여섯 가지 유형의 개방형 로드맵을 제시한다. 제안된 여섯 가지 유형의 개방형 로드맵은 P&G사의 혁신 성공 사례에 적용하여 개방형 로드맵의 유용성과 타당성에 대하여 검증하였다. 제안된 개방형 로드맵은 개방형 혁신을 지향하는 조직의 기술기획과 기술전략수립에 유용한 도구가 될 수 있을 것으로 기대된다.

• Kyungpook Mathematical Journal
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• 제56권3호
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• pp.745-754
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• 2016

In a graph G = (V, E), a non-empty set $S{\subseteq}V$ is said to be an open packing set if no two vertices of S have a common neighbour in G. The maximum cardinality of an open packing set is called the open packing number and is denoted by ${\rho}^{\circ}$. In this paper, we examine the effect of ${\rho}^{\circ}$ when G is modified by deleting a vertex.

• 충청수학회지
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• 제4권1호
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• pp.103-113
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• 1991

Some properties of a path space and the fundamental group ${\sigma}(X,x_0,G)$ of a topological transformation group (X, G, ${\pi}$) are described. It is shown that ${\sigma}(X,x_0,H)$ is a normal subgroup of ${\sigma}(X,x_0,G)$ if H is a normal subgroup of G ; Let (X, G, ${\pi}$) be a transformation group with the open action property. If every identification map $p:{\Sigma}(X,x,G)\;{\longrightarrow}\;{\sigma}(X,x,G)$ is open for each $x{\in}X$, then ${\lambda}$ induces a homeomorphism between the fundamental groups ${\sigma}(X,x_0,G)$ and ${\sigma}(X,y_0,G)$ where ${\lambda}$ is a path from $x_0$ to $y_0$ in X ; The space ${\sigma}(X,x_0,G)$ is an H-space if the identification map $p:{\Sigma}(X,x_0,G)\;{\longrightarrow}\;{\sigma}(X,x_0,G)$ is open in a topological transformation group (X, G, ${\pi}$).

• East Asian mathematical journal
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• 제23권2호
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• pp.213-227
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• 2007

In this paper the concept of fuzzy nearly C-compactness is introduced in Generalized fuzzy topological spaces. Several characterizations and some interesting properties of these spaces in Generalized fuzzy topological spaces are discussed. The properties of fuzzy almost continuous and fuzzy almost open functions in Generalized fuzzy topological spaces are also studied.

• 인간식물환경학회지
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• 제24권2호
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• pp.195-207
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• 2021

Background and objective: While response measures to particulate matters in rural areas are limited due to poor inventory record keeping in the agricultural sector, it is necessary to control agricultural waste vinyl and the emission of precursors released from open burning and the secondary generation of particulate matters. Currently, the open burning emission calculation method uses the definition prescribed in CAPSS by the National Institute of Environmental Research. Methods: This study presented an open burning emission calculation formula for agricultural waste vinyl, which is included as agricultural waste. As for activity data, the open burning ratio of agricultural waste vinyl, and the annual incineration volume provided in the Status Survey by the Ministry of Agriculture, Food, and Rural Affairs were applied. The emission factor was generated through incineration tests on three agricultural plastic film samples collected by the Korea Environment Corporation. Results: Among precursors, SOx and NOx were selected and their emission features were monitored with incineration experiment infrastructure based on the EPA 5G method. The highest emission concentration by agricultural waste type was concentrated in the first and second quarters. As for emission factor of SO₂, it was calculated at 98.25 g/kg for mulching-use LDPE, 52.31 g/kg for greenhouse-use LDPE, and 14.40 g/kg for HDPE. As for NOx, it was calculated at 18.21 g/kg for mulching-use LDPE, 16.49 g/kg for greenhouse-use LDPE, and 10.67 g/kg for HDPE. Conclusion: This test confirmed the incineration features of PE-based plastics, ascertained the SOx emission factor that had not been included in open burning in the past, and established that low NOx emission concentration is interfered by soil mixed with livestock excretions. The findings from this study are expected to contribute to improving the system for controlling air pollutants in rural environments.

• 한국컴퓨터정보학회논문지
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• 제10권6호
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• pp.219-226
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• 2005

본 논문은 4G 이동 네트워크 환경에서 재구성성을 제공하기 위한 방안으로 PARLAY X기만의 개방형 API에 관하여 서술하였다. 4C이동 네트워크 환경에서는 망 수준에서 문맥인식성, 적응성, 개인화 등과 같은 지능성이 요구된다. 그러나 기존의 PARLAY 기반 서비스 네트워크는 문맥인식성, 적응성, 개인화 등의 지능성에 대한 고려가 부족하다. 그러므로 본 논문의 목적은 4G이동 네트워크 환경에서 문맥인식성, 적응성, 개인화 등이 지원 가능한 개방형 APl를 개발하고자 하는 것이다. 본 논문에서 개방형 API는 사용자 주변에 변화하는 문맥 제약조건 및 사용자 각 개인의 선호도 정보을 파악하여, 변화하는 문맥 제약 조건 및 사용자의 선호도에 따라서 각 개인에게 적합한 적응성 있는 망 서비스를 제공하는 것을 의미하며, 개방형 API를 이용하는 예로 위치와 속도 등의 문맥정보와 사용자의 선호도 정보를 파악한 후에, 사용자에게 망에서 문맥정보 및 사용자 선호도에 따라서 각 개인에게 적합한 차별화된 QoS를 지원하는 경우를 보였다.

• 한국약용작물학회지
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• 제28권4호
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• pp.254-259
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• 2020

Background: Centella asiatica is a well-known medicinal plant having a wound healing effect. In this study, the growth, asiaticoside content, and antioxidant components and activity were investigated in C. asiatica resources under different cultivation and irrigation conditions. Methods and Results: The cultivation and irrigation methods were divided as greenhouse and open field, and sprinkler and sub irrigation. respectively. Growth characteristics were measured in aerial parts of C. asiatica. Asiaticoside content was analyzed using high performance liquid chromatography. Total polyphenol, total flavonoid and 2,2-diphenyl-1picryl hydrazyl (DPPH) radical scavenging activity were analyzed for antioxidant activities. Growth was higher under greenhouse and sub irrigation than open field and sprinkler conditions. In the leaves, asiaticoside content was 53.45 mg/g (open field) and 34.38 mg/g (sub irrigation), total polyphenol was 41.14 mg/g (open field) and 25.73 mg/g (sub-irrigation), and total flavonoid was 27.26 mg/g (open field) and 23.72 mg/g (sub-irrigation). DPPH radical scavenging activity in the leaves was 85.97 mg·ascorbic acid equivalent (AAE)/g (open field) and 54.83 mg·AAE/g (sub irrigation). Conclusions: Asiaticoside and antioxidant components and activity were not accompanied with high yield, although high growth was observed under greenhouse conditions. Therefore, cultural requirements of C. asiatica should be sufficiently considered to suit each purpose.

• Biomolecules & Therapeutics
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• 제16권2호
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• pp.118-125
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• 2008

Gardenia jasminoides (G. jasminoides) is traditionally used to treat insomnia, jaundice, emotional disorders, hepatic disease, and inflammatory disease. Previously, we found that geniposide and the water extract of G. jasminoides increased $Cl^-$ influx in neuroblastoma. Here we examined the sychopharmacological activities of G. jasminoides and its constituents. G. jasminoides extract was orally administered at 100 and 200 mg/kg, and genipin and geniposide were intraperitoneally injected at 2, 10, and 20 mg/kg. G. jasminoides extract (200 mg/kg) significantly decreased total open field activity but increased rearing activity in the center of the open field, suggesting an increase in exploratory activity. Genipin and geniposide did not change open field activity, but geniposide (20 mg/kg) increased rearing activity in the central area. The extract (200 mg/kg) significantly decreased rotarod and wire-balancing activity, but genipin and geniposide did not. No compounds influenced thiopental-induced sleeping or electroshock-induced seizures. The extract (200 mg/kg) significantly increased staying time in the open arms of the elevated plus maze and the entry ratio into the open arms, and geniposide (20 mg/kg) also increased open arm entry. Electroshock stress decreased open arm activity, but the extract and geniposide (20 mg/kg) significantly reversed that effect. This results indicate that G. jasminoides extract and geniposide alleviated anxiety with greater efficacy in stressed animals than normal animals.