• 한국조경학회지
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• 제31권1호
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• pp.34-41
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• 2003

Connectivity is a quantitative indicator of landscape structure, and connectivity of urban green areas is an indicator of ecological integrity in urban landscapes. The purposes of this study are to assess the connectivity of urban green areas in Seoul, and to develop a method of siting new green areas for better connectivity. Diverse methods for connectivity assessment and indices of connectivity are reviewed and applied to the connectivity assesment of green areas in Seoul. The indices of connectivity of green areas in Seoul turned out to be higher than expected, maybe because many of them are rather evenly distributed, serving as stepping stones, and because there are many riparian corridors, including the Han River. Analysis also shows the optimum location of new green space patches or corridors will be those spots that would link the mainland, or large green areas outside the city, and existing green areas in the city. Restoration of urban streams as ecological corridors will significantly enhance connectivity. Three different scenarios with increasing numbers of new green areas in the city were then prepared. The changes of connectivity were measured and the possible success rates of animal dispersal were simulated. The results revealed that restoration of streams will increase the connectivity and success rates of animal dispersal.

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2011년 학술대회 논문집
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• pp.87-89
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• 2011

• 한국환경생태학회지
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• 제19권2호
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• pp.150-161
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• 2005

설악산국립공원과 오대산국립공원은 20.7km 떨어져 있으나 백두대간의 중심에 위치하기 때 문에 야생동식물의 서식지와 이통통로로서 매우 중요하다 그러나 협소한 크기, 조각화, 지 리적 격리와 같은 경관적 특성에 의해 이 두 국립공원은 적절한 생태적 기능을 다하지 못하고 있다. 본 연구에서는 GIS 기법을 이용하여 두 국립공원과 인근 속초시, 고성군, 인제군, 양양군, 홍천군 일대 총 면적 $4573.6 km^2$인 지역을 대상으로 조각화 현상을 파악하였다. 또한 육식동물이며 보호종으로 지정된 삵의 서식지조건에 부합하는 경관조각을 파악하고 삵의 이동이 가능한 경관조각들의 연결망과 연결지점을 설정하였다. 다양한 도로와 인위적 시설로 인해 조사지역은 총 24,701개의 경관조각으로 단절되어 있었다. 식생과 최소 서식지면적, 조각간 거리와 같은 서식지 조건을 고려하였을 때 이 중 39개 경관조각이 삵의 잠재서식지로 선택되었다. 나아가 계방산과 방태산 일대의 3개 조각이 국립공원의 조각화와 고립화를 완화시킬 수 있는 연결망의 중심으로 확인되었다. 본 연구는 또한 점봉산과 방태산 일대의 조각이 삵이 두 국립공원으로 분산할 수 있는, 공급지로서 작용할 수 있음을 보여 주었다. 거의 모든 국립공원이 조사된 두 국립공원과 유사한 경관적 문제를 가지고 있기 때문에 야생 생물을 보전하기 위해서는 국립 공원과 인근 지역에서의 조각화 현상과 경관조각의 연결성을 평가하는 과제가 매우 시급하다고 사료된다.

• 대한화학회지
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• 제54권1호
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• pp.65-70
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• 2010

유색미인 흑남벼(Oryza sativa cv. Heugnambyeo) 미강의 ethylacetate 가용성 용매분획물로부터 NO 생성을 저해시키는 단일화합물을 순수 분리한 후, HREI-MS 및 2D-NMR 분석을 통해 화학구조를 4-carboethoxy-6-methoxy-2-quinolone (1)과 4-carboethoxy-6-hydroxy-2-quinolone (2)으로 명명하였다.

• Fisheries and Aquatic Sciences
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• 제27권3호
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• pp.145-158
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• 2024

Life history characteristics, habitat landscape, and historical events are believed to have shaped the patterns of genetic variation in many taxa. The bony lip barb, Osteohilus vittatus, represent a potamodromous fish that complete all life cycle in freshwater and is widely distributed in Southeast Asia. It usually lives in small rivers and other freshwater habitats, and movement between habitats for either food or reproduction has been typical. These life history characteristics may promote gene flow, leading to less structured populations. However, many freshwater habitats are fragmented, which restricts gene flow. We investigate how this interplay has shaped patterns of genetic variation and phylogeographic structure within this species in the Sundaland, a biodiversity hotspot with a complex geological history, using mitochondrial cytochrome oxidase I (mtCOI) as a genetic marker. Forty-six mtCOI sequences of 506 bp long were collected from ten localities, eight geographically isolated and two connected. The sequences were used for population genetic and phylogeographic analyses. Our results showed a low genetic diversity within populations but high between populations. There was a deep phylogeographic structure among geographically isolated populations but a lack of such structure in the connected habitats. Among geographically isolated populations, sequence divergence was revealed, ranging from 1.8% between Java and Sumatra populations to 12.2% between Malaysia and Vietnam. An indication of structuring was also observed among localities that are geographically closer but without connectivity. We conclude that despite high dispersal capacity, the joint effects of historical events, long-term geographic isolation associated with sea level oscillation during the Pleistocene, and restricted gene flow related to lack of habitat connectivity have shaped the phylogeographic structure within the O. vittatus over the Sundaland.

• Smart Structures and Systems
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• 제22권2호
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• pp.167-174
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• 2018

Digital input and output modules are widely used to connect digital sensors and actuators to automation systems. Digital I/O modules provide flexible connectivity extension to numerous sensors and actuators and protect systems from high voltages and currents by isolation. Components in digital I/O modules are inevitably affected by operating and environmental conditions, such as high voltage, high current, high temperature, and temperature cycling. Because digital I/O modules transfer signals or isolate the systems from unexpected voltage and current transients, their failures may result in signal transmission failures and damages to sensitive circuitry leading to system malfunction and system shutdown. In this study, the lifetime of optocouplers, one of the critical components in digital I/O modules, was predicted using Bayesian tracking approaches. Accelerated degradation tests were conducted for collecting the critical performance parameter of optocouplers, current transfer ratio (CTR), during their lifetime. Bayesian tracking approaches, including extended Kalman filter and particle filter, were applied to predict the failure. The performance of each prognostic algorithm was then compared using accuracy and robustness-based performance metrics.

• 한국어교육
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• 제23권1호
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• pp.257-282
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• 2012

Sakhalin, Russia is a very specific area for Korean language education. The imposed separation and isolation in this region means the language in Sakhalin is mixed with South Korean, North Korean, Gyeongsang Province dialect, Japanese, and Russian. Scrutiny of the use of the actual language of Sakhalin Koreans is needed, and it is required in supporting Korean language education. In this study, I will cover: 1. Approach should differ depending on the situation of Korean, foreigners, Korean Language School(Hangeul Hakgyo) and Korean classes in local Schools. 2. Tailor-made textbooks for Sakhalin are required. 3. Korean textbooks to match local circumstances are needed. There should be a basic writing text written by a local Korean department professor and supervision or modification, supplements from Korean language education researchers in Korea. 4. Enlarged Korean training programs are needed. Furthermore, if Korean and Russian university students are to study in Korea, there should be programs offering a dual degree among other things. 5. Methodical, overall examination of overseas Korean regions like Sakhalin is necessary. Also in the case of far east Russia, connectivity between Vladivostok, Khabarovsk and Sakhalin needs to be strengthened.

• ALGAE
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• 제37권2호
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• pp.123-133
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• 2022

Genetic diversity and distribution patterns of marine macroalgae are increasingly being documented in Southeast Asia. These studies show that there can be significant levels of genetic diversity and isolation between populations on either side of the Thai-Malay Peninsula. Bostrychia tenellla is a common filamentous red seaweed in the region and the entity is represented by at least two cryptic species. Despite being highly diverse and widespread, genetic variation and population structure of this species complex remains understudied, especially around the Thai-Malay Peninsula. We analyzed genetic diversity and inferred the phylogeographic pattern of specimens identified as B. tenella using the plastid RuBisCo spacer from samples from the Andaman Sea and the Gulf of Thailand. Our genetic analysis confirmed the occurrence of the two cryptic B. tenella species (B and C) along both coasts. Cryptic species B was more common in the area and displayed higher genetic diversity than species C. Historical demographic analyses indicated a stable population for species B, but more recent population expansion for species C. Our analyses also revealed that both cryptic species from the Andaman Sea possessed higher genetic diversity than those of the Gulf of Thailand. We also detected moderate to high levels of gene flow and weak phylogeographic structure of cryptic species B between the two coasts. In contrast, phylogeographic analysis showed genetic differences between populations of both cryptic species within the Andaman Sea. Overall, these results suggest that cryptic B. tenella species around Thai-Malay Peninsula may have undergone different demography histories, and their patterns of genetic diversity and phylogeography were likely caused by geological history and regional sea surface current circulation in the area.

• 마이크로전자및패키징학회지
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• 제23권4호
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• pp.31-34
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• 2016

System In Package (SiP) is getting popular and momentum for the recent wearable, IoT and connectivity application apart from mobile phone. This is driven by market demands of cost competitive, lighter and smaller/thinner and higher performance. As one of many semiconducting assembly products, Leadframe product has been widely used for low cost solution, light/ small and thin form factor. But It has not been applied for SiP although Leadframe product has many advantages in cost, size and reliability performance. SiP is mostly based on laminate substrate and technically difficult on Leadframe substrate because of a limitation in SMT performance. In this paper, Leadframe based SiP product has been evaluated about key technical challenges in SMT performance and electrical shield technology. Mostly Leadframe is considered not available to apply EMI shield because of tie-bar around package edge. In order to overcome two major challenges, connection bars were deployed properly for SMT pad to pad and additional back-side etching was implemented after molding process to achieve electrical isolation from outer shield coating. This product was confirmed assembly workability as well as reliability.

• 한국광학회지
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• 제16권3호
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• pp.261-265
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• 2005

광자결정의 밴드갭이 크면서도 모든 편광방향에 대해 동일하게 설계될 수 있다면, 이러한 광밴드갭은 다양한 소자의 응용에 있어 보다 유용해 질 수 있다. 현재까지는 원형의 공기구멍으로 이루어진 삼각격자 구조가 가장 큰 광밴드갭을 갖는 것으로 알려져 왔으나, 본 논문에서는 각종 구조적 변화에 의한 밴드갭의 변화경향을 분석하고 체계화함에 따라, 모든 편광방향에 대해 광밴드갭이 동일하면서 가장 크게 되는 새로운 격자구조를 제안하였다. 이 구조의 광밴드갭 비율$(\Delta\omega/\omega)$은 기존의 삼각격자에 비해 약 $30\%$ 정도 증대된 것임을 확인하였다.