• Title/Summary/Keyword: hotspots

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Local and regional steppe vegetation palatability at grazing hotspot areas in Mongolia

  • Amartuvshin, Narantsetsegiin;Kim, Jaebeom;Cho, Nanghyun;Seo, Bumsuk;Kang, Sinkyu
    • Journal of Ecology and Environment
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    • v.46 no.1
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    • pp.76-84
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    • 2022
  • Background: Climate and livestock grazing are key agents in determining current Mongolian steppe vegetation communities. Together with plant coverage or biomass, palatability of steppe community is regarded as a useful indicator of grassland degradation, in particular, at grazing hotspots in arid and semi-arid grasslands. This study analyzed relationships between livestock grazing pressure and steppe vegetation palatability at three summer pastures with different aridity (dry, xeric, and mesic) and livestock numbers (1,100, 1,800, and 4,100 sheep units, respectively). At each site, it was surveyed coverage, biomass, and species composition of different palatability groups (i.e., palatable [P], impalatable [IP], and trampling-tolerant [TT]) along a 1-km transect from grazing hotspots (i.e., well) in every July from 2015 to 2018. Results: In results, total vegetation coverage increased with wetness, 7 times greater at mesic site than dry one in averages (33.1% vs. 4.5%); biomass was 3 times higher (47.1 g m-2 vs. 15.7 g m-2). Though P was the dominant palatability group, the importance of IP in total coverage increased with aridity from mesic (0.6%) to dry (40.2%) sites. Whereas, TT increased with livestock numbers across sites. Locally, IP was observed more frequently near the wells and its spatial range of occurrence becomes farther along the transects with aridity across sites from mesic (< 100 m) to dry (< 700 m from the well). Conclusions: Our results showed that the importance of IP and its spatial distribution are different at both local and regional scales, indicating that the palatability parameters are sensitive to discern balance between selective-grazing demand and climate-driven foraging supply in Mongolian rangelands.

Palmophyllum crassum, a New Record of an Ancient Species in Green Algae from Korea

  • Lee, Hyung Woo;Kim, Myung Sook
    • Korean Journal of Environmental Biology
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    • v.35 no.3
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    • pp.319-328
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    • 2017
  • The continuous exploration in deep seawater from Korea makes us lead the discovery of ancient Chlorophyta, Palmophyllum, in the Korean coast. The phylogenetic analyses of 18S rRNA and rbcL genes demonstrate that our specimens are Palmophyllum crassum (Naccari) Rabenhorst, recorded in Japan and clearly distinguished from P. umbracola from New Zealand and California, USA. Palmophyllum crassum grows in the subtidal region, 8-30 m deep, and has a crustose thallus which is closely adherent to substrates such as non-geniculate crustose coralline algae, sponge, shells, or rocks. P. crassum is composed of numerous spherical cells embedded in the gelatinous matrix. The discovery of this ancient green seaweed implies that the Korean coast is one of the hotspots of algal species diversity and has the suitable marine environment for algal speciation. We suggest the grounds to conserve the Korean coast environmentally as the biodiversity center of marine species by studying the phylogeny of seaweeds.

CAMR: Congestion-Aware Multi-Path Routing Protocol for Wireless Mesh Networks

  • Jang, Seowoo;Kang, Seok-Gu;Yoon, Sung-Guk
    • Journal of Electrical Engineering and Technology
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    • v.12 no.1
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    • pp.411-419
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    • 2017
  • The Wireless Mesh Network (WMN) is a multi-hop wireless network consisting of mesh routers and clients, where the mesh routers have minimal mobility and form the backbone. The WMN is primarily designed to access outer network to mesh clients through backhaul gateways. As traffic converges on the gateways, traffic hotspots are likely to form in the neighborhood of the gateways. In this paper, we propose Congestion Aware Multi-path Routing (CAMR) protocol to tackle this problem. Upon congestion, CAMR divides the clients under a mesh STA into two groups and returns a different path for each group. The CAMR protocol triggers multi-path routing in such a manner that the packet reordering problem is avoided. Through simulations, we show that CAMR improves the performance of the WMN in terms of throughput, delay and packet drop ratio.

Functional annotation of de novo variants from healthy individuals

  • Lee, Jean;Hong, Sung Eun
    • Genomics & Informatics
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    • v.17 no.4
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    • pp.46.1-46.7
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    • 2019
  • The implications of germline de novo variants (DNVs) in diseases are well documented. Despite extensive research, inconsistencies between studies remain a challenge, and the distribution and genetic characteristics of DNVs need to be precisely evaluated. To address this issue at the whole-genome scale, a large number of DNVs identified from the whole-genome sequencing of 1,902 healthy trios (i.e., parents and progeny) from the Simons Foundation for Autism Research Initiative study and 20 healthy Korean trios were analyzed. These apparently nonpathogenic DNVs were enriched in functional elements of the genome but relatively depleted in regions of common copy number variants, implying their potential function as triggers of evolution even in healthy groups. No strong mutational hotspots were identified. The pathogenicity of the DNVs was not strongly elevated, reflecting the health status of the cohort. The mutational signatures were consistent with previous studies. This study will serve as a reference for future DNV studies.

VIRTUAL PROTOTYPING ENGINEERING FOR COMPLEX PRODUCT

  • Li, Bo-Hu;Xudong Chai;Wenhai Zhu
    • Proceedings of the Korea Society for Simulation Conference
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    • 2001.10a
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    • pp.123-130
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    • 2001
  • At present, the virtual prototyping technology for complex product is one of the research and application hotspots in current simulation technology. In authors viewpoint, the virtual prototype development for complex product has become a systematic engineering, which can be called the complex product virtual prototyping engineering (CPVPE). In this paper, the architecture, key technologies and its supporting environment of CPVPE are primary discussed firstly. Combined with the research project and primary practice undertaken by the authors, a typical application demonstration of the aerospace complex product virtual prototyping engineering (including mechanism, dynamics, software and control system) is also introduced based on the virtual prototype supporting environment developed by the authors. Finally, some further research works on CPVPE are also presented in this paper.

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From Emerging to Submerging Economies: New Policy Challenges for Research and Innovation

  • Soete, Luc
    • STI Policy Review
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    • v.4 no.1
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    • pp.1-13
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    • 2013
  • The Schumpeterian process of "creative destruction", associated with the emergence and diffusion of new radical, so-called "general purpose" technologies, has throughout history impacted wealth and income, jobs creation, jobs displacement, and the emergence and submergence of new hotspots of innovation. Emerging countries have benefited most from such a renewing of those societies' dynamics, leading them to higher levels of economic development and welfare. Doing so they have shown a remarkable capacity in moving upstream in the value chain, from outsourcing of manufacturing activities to autonomous process technology development, product development, design, and applied research. At the same time however, such Schumpeterian processes have now and then turned into exactly opposite processes of "destructive creation." Such processes seem to have become common among what could be called "submerging" economies: innovation only benefitting a few at the expense of many with as a result an opposite pattern of a long term reduction in overall welfare, productivity, and employment growth.

Measurement-Based Propagation Channel Characteristics for Millimeter-Wave 5G Giga Communication Systems

  • Lee, Juyul;Liang, Jinyi;Kim, Myung-Don;Park, Jae-Joon;Park, Bonghyuk;Chung, Hyun Kyu
    • ETRI Journal
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    • v.38 no.6
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    • pp.1031-1041
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    • 2016
  • This paper presents millimeter-wave (mmWave) propagation characteristics and channel model parameters including path loss, delay, and angular properties based on 28 GHz and 38 GHz field measurement data. We conducted measurement campaigns in both outdoor and indoor at the best potential hotspots. In particular, the model parameters are compared to sub-6 GHz parameters, and system design issues are considered for mmWave 5G Giga communications. For path loss modeling, we derived parameters for both the close-in free space model and the alpha-beta-gamma model. For multipath models, we extracted delay and angular dispersion characteristics including clustering results.

The Manifold Research Fields of Facebook: A Bibliometric Analysis

  • Baran, Katsiaryna S.;Ghaffari, Hilda
    • Journal of Information Science Theory and Practice
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    • v.5 no.2
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    • pp.33-47
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    • 2017
  • The aim of the present study is to analyze the present state and evolution of scientific research with regard to the scientific production generated on Facebook. Good analysis proves challenging due to the large number of publications about the topic. That is why we concentrate on Scopus as the information service with the highest coverage on this topic. We performed a bibliometric analysis on Facebook-related research from 2005 to 2016. We identified publication output, subject areas, journals, and countries in order to assess the publication trends and research hotspots in this field. Moreover, an author network graph and a geo map were applied to visualize some research trends. These results provide a basis for better understanding of the development of global Facebook research.

Intellectual Structure of the Altmetrics field: A Co-Word Analysis (Co-word를 이용한 알트메트리얼 필리트의 지적 구조 연구)

  • Li, Jiapei;Li, Xiaomeng;Lee, HyunChang;Shin, SeongYoon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.10a
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    • pp.148-150
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    • 2017
  • In recent years, "altmetrics", given birth by social media and the academic community, have become a metric source for measuring the academic impact of scientific literature. This study has undertaken a co-word analysis of author keywords in "Altmetrics" articles from the Web of Science database from 2012 to 2017 and used a co-occurrence matrix to create a clustering of the words. "Altmetrics" co-occurrence network map was derived and the research hotspots was analyzed.

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Characteristics of Korean Trawl Fisheries in the Southwest Atlantic Ocean (남서대서양 한국트롤어업의 조업특성)

  • Ku, Jeong Eun;Kim, Eunjung;Choi, Seok-Gwan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.54 no.4
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    • pp.517-525
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    • 2021
  • Trawl fishing is a major concern worldwide, and there is considerable debate about its impact on marine ecosystems. In this study, we used the vessel monitoring system (VMS) data collected in the southwest Atlantic Ocean from 2016 to 2019 to estimate the fishing effort and trawled area. Spatial distribution of trawl activities according to the latitude and longitude and the hotspots where fishing was concentrated each year were identified. Trawling activities of the Korean vessels were mainly distributed between 40-52°S and 56-63°W. The species caught during the fishing period comprised five Cephalopoda, three Chondrichthyes, ten Osteichthyes, and other fish. The Argentine hake Merluccius hubbsi and Argentine shortfin squid Illex argentinus were the dominant species in the catch.