• Korean Journal of Medicinal Crop Science
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• v.12 no.1
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• pp.17-23
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• 2004

This study was carried out to obtain the basic information on mating parents and selection for high yielding safflower breeding. Thirty nine world safflower lines, which had collected from 13 countries of origjn, were evaluated for major agronomic characters, correlation and path-coefficients. The results obtained were summarized as follows. Days to flowers ranged from 83 days to 100 days. Days to flower of most foreign lines were later than that of domestic lines. Plant height ranged from 75 cm to 162 cm. The plant height and stem diameter of most foreign lines were higher than those of domestic lines. The leaf number and size of domestic lines were much more than those of foreign lines. The total branch numbers of foreign lines were more than domestic lines. Particularly, the number of third branch ranged from 0 to 25 and there were none in domestic lines. The number of corolla of foreign lines was much more than that of domestic lines. The yield of foreign lines collected from Central Asia and United States of America were more than any others. Significantly positive correlations were observed between yield and days to flower, stem diameter, the number of branch and the number of corolla. In the analysis of path-coefficient, the highest direct effects on yield was the number of corolla followed by the number of total branch, whereas those of the number of second branch and stem diameter were negative.

• Proceedings of the KGS Conference
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• 2002.05a
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• pp.77-80
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• 2002

본 논문의 연구목적은, 우리나라 감자재배지역의 분포 특징과 그 중심지를 밝혀 보는데 있다. 이와 같은 목적을 위하여 감자가 외국에서 우리나라에 전파해온 경로와 한국 내에서 의 전파경로를 알아보고, 7개 지역의 감자재배지역의 특징, 우리나라 감자재배의 생산량, 재배면적, 재배농가, 각 시기별 감자 재배지의 중심지와 남한의 감자재배 중심지를 구하였다. 이와 같은 연구내용은 주어진 자연환경에 인간이 어떻게 적응해가면서 살아가는지를 공부하는 지리학의 전통적인 개념인 자연과 인간과의 관계를 이해하는데 도움을 줄 수 있을 뿐만 아니라, 초 중등학교 및 대학에서 공부하는 한국지리 교육과정의 학습자료로서 유용하게 쓰일 수 있을 것으로 기대한다. 연구방법은 문헌연구과 1970년부터 1995년까지의 전국의 시.군별 감자재배지역의 입지계수를 구하여 연구하였다. 그 결과를 요약하면 다음과 같다. 1. 감자가 한국에 처음으로 재배된 것은 1824년(조선조 순조24년) 인데, 전파과정을 살펴보면, 안데스산지의 페루(1500년대) $\longrightarrow$ 에스파냐(1532년) $\longrightarrow$ 중국(1650년) $\longrightarrow$ 한국(1824년)순으로 전파되어온 북방전래설과 영국의 감자가 1832년 충청도의 서산으로, 일본 감자가 1920년에 수원으로 전파되었다는 남방전래설이 있다 2. 감자는 한국 전 지역에서 재배되는 중요 농작물이다 그러나 우리나라의 지형이 남북으로 깊게 뻗은 반도국이므로 위도와 지형 차이에 따라 기온과 고도가 다르게 나타나는데, 이러한 자연적인 요인의 영향이 가장 큰 요인이 되어 고랭지 여름재배지역.중산간 봄재배지역.중부평야 봄재배지역 남부평야 봄재배지역 남부해안 2기작 재배지역.남부 겨울재배지역.제주 가을 월동재배지역 등 7개 지역으로 구분되어 재배된다. 3. 우리나라(남한)의 감자 재배지의 중심지는 강원도 고랭지 여름재배지역과 제주도 가을 월동재배지역, 소백산맥과 진안고원이 만나는 부근 산지지역의 남원군.구례군 거창군.고령군과 남해안의 밀양군.양산군이다. 강원도 지역과 제주도 두지역이 전테 재배면적의 52%를 점유하여 감자 재배지의 핵심지를 이룬다. 4. 한국 감자 재배지역 중심지의 지리적 특징은, 높은 산지지역의 산록완사면에 밭작물로 재배된다는 점과 교통이 불편한 지역으로서 도시화와 산업화 지역의 그늘 지역이 대부분이다. 강원도의 감자 재배지는 감자재배에 적합한 자연환경과 화전농업의 전통, 감자 재배기술의 전파, 중앙정부와 지방정부가 지원하는 각종 연구소 분포와 영농지도, 씨감자 생산과 협동조합의 판로 개척, 도로 개설과 포장 등의 인문지리적 요인이 영농조건을 개선하고 감자 판매를 위한 시장접근을 용이하게 하여, 남한 최대의 감자 재배지역을 형성하였다. 제주도는 산지지형과 따뜻한 기온으로 2기작이 가능하고, 감자가공 공장설립과 교통발달에 따른 육지 시장과의 접근이 용이해졌기 때문에 남한에서 2번째로 큰 감자재배지역이 되었다.(요약 및 결론에서 발췌)

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.2A
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• pp.114-126
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• 2011

Video streaming over wireless multi-hop networks(WMNs) contains the following challenges from channel fading and variable bandwidth of wireless channel, and it cause degradation of video streaming performance. To overcome the challenges, currently, WMNs can use Forward Error Correction (FEC) mechanism. In WMNs, traditional FEC schemes, E2E-FEC and HbH-FEC, for video streaming are applied, but it has long transmission delay, high computational complexity and inefficient usage of resource. Also, to distinguish network status in streaming path, it has limitation. In this paper, we propose monitoring-based coordination of network-adaptive hop-to-end(H2E) FEC scheme. To enable proposed scheme, we apply a centralized coordinator. The coordinator has observing overall monitoring information and coordinating H2E-FEC mechanism. Main points of H2E-FEC is distinguishing operation range as well as selecting FEC starting node and redundancy from monitored results in coordination. To verify the proposed scheme, we perform extensive experiment over the OMF(Orbit Measurement Framework) and IEEE 802.1la-based multi-hop WMN testbed, and we carry out performance improvement, 17%, from performance comparison by existing FEC scheme.

• The Journal of the Petrological Society of Korea
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• v.1 no.1
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• pp.1-24
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• 1992

Precambrian metamorphic rocks of the Gapyeong-Cheongpyeong area consist of banded gneiss, augen gneiss, leucocratic gneiss, quartz schist and quartzite, together with minor intercalations of serpentinite, amphibolite and marble. Mineral assemblages of meta-sedimentary rocks are classified into three types: sillimanite-free; sillimanite-bearing; and sillimanite+K-feldspar-bearing assemblages. Compositions of metamorphic phases depend on the type of mineral assemblages. In particular, the Ca contents of plagioclase and garnet are high in sillimanite-free assemblges. Kyanite occurs in three samples, and coexists with sillimanite in one sample. The presence of kyanite indicates that metamorphic rocks of the study area have experienced the Barrovian type metamorphism. Peak metamorphic conditions estimated from various geothermobarometers and phase equilibria are 618-674$^{\circ}C$ and 6.5${\pm}$2.0 kbar for sillimanite-free assemblages, and 701-740$^{\circ}C$ and 4.4${\pm}$0.8 kbar for sillimanite-bearing assemblages, respectively. Furthermore, a clockwise P-T-time path is deduced for the study area, based on the following observations: (1) the polymorphic transition of kyanite to sillimanite, (2) the occurrence of sillimanite and K-feldspar belonging to the upper amphibolite facies, and finally (3) the retrograde metamorphism characterized by muscovite-, chlorite-, and actinolite-bearing assemblages.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.537-546
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• 2019

This study verified the factors influencing continuous intention to use of OTT service users through technology acceptance model and extension. For this purpose, the main results were derived through correlation analysis and path analysis using SPSS 21.0 program and AMOS 21.0 program. The summary is as follows. First, perceived ease of use was found to have a statistically significant positive effect on perceived usefulness. Second, perceived ease of use did not have a statistically significant effect on continuous intention to use. Third, the perceived usefulness has a statistically significant positive effect on continuous intention to use. Fourth, perceived innovativeness has a statistically significant positive effect on perceived ease of use. Fifth, perceived innovativeness has a statistically significant positive effect on continuous intention to use. Sixth, perceived playfulness has a statistically significant positive effect on continuous intention to use. The above results will be meaningful in that it has revealed a path to understand the extension of the technology acceptance model of OTT services and acceptance of OTT services.

• The Journal of Korean Institute of Next Generation Computing
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• v.13 no.6
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• pp.7-20
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• 2017

The advancement of cloud and big data and the considerable growth of traffic have increased the complexity and problems in the management inefficiency of existing networks. The software-defined networking (SDN) environment has been developed to solve this problem. SDN enables us to control network equipment through programming by separating the transmission and control functions of the equipment. Accordingly, several studies have been conducted to improve the performance of SDN controllers, such as the method of connecting existing legacy equipment with SDN, the packet management method for efficient data communication, and the method of distributing controller load in a centralized architecture. However, there is insufficient research on the control of SDN in terms of the quality of network-using applications. To support the establishment and change of the routing paths that meet the required network service quality, we require a mechanism to identify network requirements based on a contract for application network service quality and to collect information about the current network status and identify the violations of network service quality. This study proposes a method of identifying the quality violations of network paths through ontology to ensure the network service quality of applications and provide efficient services in an SDN environment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4B
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• pp.329-337
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• 2009

In this study we briefly introduce the electronic float system based on the GPS and RF communication technology and present some field application results. The system is capable of operating 15 floats simultaneously for making discharge measurement. Since the electronic floats (EFs) acquire flow paths, they can improve velocity measurement accuracy up to 10%. Additionally, measured velocities by the EFs show good agreement with those by an ADCP. Relative difference in sub-section area calculated by the electronic and conventional float methods is -79~71% and, due to convergent tendency of floats flowing along near banks, it increases much larger. It is possible to improve accuracy up to 5~6% in making discharge measurement by the electronic floats at site with irregular flow paths and section arrangement. The electronic float system is capable of calculating more accurate velocity and section area using position information based on GPS. By real-time measurement of velocity, cross-section area and discharge, the electronic float system is expected to reduce manpower and improve accuracy, rapidity and efficiency of flood discharge measurements.

• Journal of the Korean Society of Radiology
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• v.83 no.3
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• pp.658-668
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• 2022

Purpose To evaluate the effectiveness of the transradial artery approach (TRA) for treating malfunctioning arteriovenous fistulas (AVFs) in patients on hemodialysis. Materials and Methods A retrospective analysis was conducted in this single-center study of TRA endovascular procedures in 73 patients (43 male and 30 female; mean age of 67.4 years (range, 42-92 years) with malfunctioning AVFs, between January 2008 and April 2019. Patients' baseline and lesion characteristics, technical and clinical success, and complications were evaluated, and functional patency was analyzed using the Kaplan-Meier method. Results Radial artery approaches were successful in all patients. Angioplasty performed using the TRA achieved technical and clinical success rates of 98.6%(72/73) and 91.7%(67/73), respectively. The median primary patency time was 18.8 ± 15.9 months. The primary functional patency rates at 3, 6, and 12 months were 82.1%, 68.6%, and 63.9%, respectively. There were no major complications or adverse events, such as hand ischemia, related to the radial artery approach. Conclusion In selected cases, the TRA can be used complementary to the transvenous approach to treat malfunctioning AVFs.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.6
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• pp.92-100
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• 2008

Ad-hoc network is a collection of wireless mobile hosts forming a temporary network without the aid of any centralized administration or reliable support services such as wired network and base stations. Recently, Ad-hoc networks are evolving to support multimedia contents according to expansion of ad hoc multi-hop communication system. Wireless ad-hoc network is different from the conventional wired network by frequent changes in network topology, number of routers and resources, there are a number of problems in applying conventional routing protocol to ad-hoc network. The AODV routing protocol is proposed for mobile node in ad-hoc networks. AODV protocol that provides to guarantee QoS for data transmission in ad hoc networks that link break frequently occurs. In this paper, AODV routing protocol based NDIS(Network Driver Interface Specification) is implemented. We design high performance image transmission that can operate with software(AODV) for ad-hoc networks without degradation. and verify operation of AODV routing protocol on the test bed.

• Journal of KIISE
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• v.44 no.9
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• pp.976-985
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• 2017

Wireless mesh network (WMN) is a promising technology for building a cost-effective and easily-deployed wireless networking infrastructure. To efficiently utilize limited radio resources in WMNs, packet transmissions (particularly, redundant packet transmissions) should be carefully managed. We therefore propose a lightweight traffic redundancy elimination (LTRE) scheme to reduce redundant packet transmissions in software-defined wireless mesh networks (SD-WMNs). In LTRE, the controller determines the optimal path of each packet to maximize the amount of traffic reduction. In addition, LTRE employs three novel techniques: 1) machine learning (ML)-based information request, 2) ID-based source routing, and 3) popularity-aware cache update. Simulation results show that LTRE can significantly reduce the traffic overhead by 18.34% to 48.89%.