• Economic and Environmental Geology
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• v.49 no.5
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• pp.381-388
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• 2016

The purpose of this study is to integrate and visualize using mapping techniques based on precise seabed geomorphology, seafloor backscattering images and high-resolution underwater images of the nearshore area around the Dokdo, in the East Sea. We have been obtained the precise topography map using multibeam echosounder system around the nearshore area(~50 m) of the southern part of the Seodo. Side scan sonar survey for analysis seafloor backscattering images was carried out in the same area of topography data. High-resolution underwater images(zone(a), zone(b), zone(c)) were taken in significant habitat scope of the nearshore area of the southern part of the Seodo. Using the results of bathymetry, seafloor backscattering images, high-resolution underwater images, we performed an integrated visualization about the nearshore area of the Dokdo. The integrated visualizing techniques are possible to make the seabed characteristic mapping results of the nearshore area of the Dokdo. The integrated visualization results present more complex and reliable information than separate geological products for seabed environmental mapping study and it is useful to understand the relation between seafloor characteristics and topographic environments of the study area. The integrated visualizing techniques and mapping analysis need to study sustainably and periodically, for effective monitoring of the nearshore ecosystem of the Dokdo.

• Korean Journal of Environmental Biology
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• v.36 no.2
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• pp.180-189
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• 2018

Agricultural landscapes in Korea comprise a large cultivation area of rice paddies, other crops, and forests which surround the cropland and the farmers' residential village. The forests in this agricultural landscape play important roles as ecological corridors and refuges for plants and animals in this agroecosystem. The present study investigated the spatial and temporal diversity patterns among these components of the agroecosystem to provide baseline data that describes how fauna change in the studies system. Insect sampling was conducted at four sites in two regions, Chungcheong (Ockcheon and Geumsan) and Jeonnam (Younggwang and Haenam), from March to August of 2014, using an UV light trap for moths and five pitfall traps for beetles. Beetles comprised 225 species and 2,457 individuals in 35 families, while moths consisted of 141 species and 403 individuals in 17 families. Beetles showed higher diversity in Chungcheong than Jeonnam, while moths showed no difference in diversity between regions. Forests showed the highest number of species and individuals, followed by orchards and rice paddies. The food preference of beetles showed that forests contained a higher proportion of herbivores, while orchards and rice paddies had a higher proportion of carnivores. Temporal changes in moths in the two regions were synchronous, while those of beetles were nonsynchronous. Moths increased from spring to summer across all habitats, especially in rice paddies during summer. Beetles also increased from spring to summer in orchards and rice paddies, although the beetles in the forests increased in the middle of summer. A detailed and long-term study is needed to reveal the causes of different diversity patterns of taxa among the different habitats within the agroecosystems.

• Journal of Food Hygiene and Safety
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• v.35 no.4
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• pp.291-303
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• 2020

Marine organism-derived toxins have negative effects not only on human health but also in aquaculture, fisheries, and marine ecosystems. However, traditional analytical methods are insufficient in preventing this threat. In this paper, we reviewed new rapid methods of toxin detection, which have been improved by adopting diverse types of nanomaterials and technologies. Moreover, we herein describe the main strategies for toxin detection and their related sensing performance. Notably, to popularize and commercialize these newly developed technologies, simplifying the process of pre-treating real samples real samples is very important. As part of these efforts, numerous studies have reported pretreatment methods based on the antibody-immobilized magnetic nanoparticles, and some cases have applied nanoparticles to enhance the sensing performance by utilizing the intrinsic catalytic activity. Furthermore, some reports have introduced fluorescent nanoparticles, such as quantum dots, to represent the lower detection limits of conventional enzyme-based colorimetric methods and lateral flow assays. Some studies using electrochemical measurements based on aptamer-nanoparticle complexes have also been announced. In addition, as the response to new toxins generated by changes in the marine environment is still lacking, further research on diagnostic and detection is also greatly needed for these kinds of marine toxins and their derivatives.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.2
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• pp.70-80
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• 2003

We report the first direct measurement of $CO_2$ flux over Kwangneung broadleaf deciduous forest, one of the tower flux sites in KoFlux network. Eddy covariance system was installed on a 30 m tower along with other meteorological instruments from June to August in 2002. Although the study site was non-ideal (with valley-like terrain), turbulence characteristics from limited wind directions (i.e., 90$\pm$45$^{\circ}$) was not significantly different from those obtained at simple, homogeneous terrains with an ideal fetch. Despite very low rate of data retrieval, preliminary results from our analysis are encouraging and worthy of further investigation. Ignoring the role of advection terms, the averaged net ecosystem exchange (NEE) of $CO_2$ ranged from -1.2 to 0.7 mg m$^{-2}$ s$^{-1}$ from June to August in 2002. The effect of weak turbulence on nocturnal NEE was examined in terms of friction velocity (u*) along with the estimation of storage term. The effect of low uf u* NEE was obvious with a threshold value of about 0.2 m s$^{-1}$ . The contribution of storage term to nocturnal NEE was insignificant; suggesting that the $CO_2$ stored within the forest canopy at night was probably removed by the drainage flow along the hilly terrain. This could be also an artifact of uncertainty in calculations of storage term based on a single-level concentration. The hyperbolic light response curves explained ＞80% of variation in the observed NEE, indicating that $CO_2$ exchange at the site was notably light-dependent. Such a relationship can be used effectively in filling up the missing gaps in NEE data through the season. Finally, a simple scaling analysis based on a linear flow model suggested that advection might play a significant role in NEE evaluation at this site.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.129-135
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• 2010

The relationship between rainfall variable and zooplankton dynamics was studied in the Upo wetland, an ecosystem of international importance. Water sampling was conducted on biweekly basis from January 2002 to December 2007 in the study site. The annual average of total rainfall was 1,324 mm during the study period. Total rainfall amount in 2003 (1,766 mm) was unusually high, while total rainfall amount in 2005 (975 mm) was exceptionally lower than the average. Most of basic limnological parameters (water temperature, dissolved oxygen, pH, conductivity and turbidity) in the study site were greatly influenced by the flooding events and rainfall amounts in summer. There were statistically significance between seasonal and inter-annual differences in zooplankton abundance and the total rainfall amount (ANOVA, P<0.05). Zooplankton abundance was high in summer (mean${\pm}$s.d.: $1,594{\pm}1,598\;Ind.\;L^{-1}$) and low in winter ($246{\pm}234\;Ind.\;L^{-1}$. The 47% of annual total zooplankton abundance in the study site were observed in summer. The seasonal pattern of rotifers was similar to that of total zooplankton. This reflected the fact that rotifers strongly dominated and occupied ca. 65% the total zooplankton abundance (annual mean: $398{\pm}1,139\;Ind.\;L^{-1}$, n=149), followed by cladocerans ($65{\pm}140\;Ind.\;L^{-1}$) and copepods ($58{\pm}84\;L^{-1}$). Planktonic rotifers such as Keratella cochlearis, Polyarthra spp. and Brachionus calyciflorus were dominant from winter to spring and attached rotifers such as Lecane spp., Monostyla spp. and Trichocerca spp., observed commonly from spring to fall. Among the environmental variables considered, rainfall in summer seemed to play the most important role in determining characteristics of zooplankton community dynamics in the Upo wetland.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.1
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• pp.109-132
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• 2011

While the resource-based view suggests that a firm's competitive advantage rests on a set of valuable, rare and inimitable resources more generally (Barney, 1991), research in new firms has more specially indicated a link between initial resources and early performance and survival (Bruderl and Schussler, 1990; Fichman and Levinthal, 1991; Carroll et al., 1996). The RBV primarily focuses on the particular resources, and their characteristics, that provide the potential for advantage (Conner, 1991). Yet in order to realize this advantage, organizations must not only develop their resources, but also effectively deploy them (Admit and Shoemaker, 1993). This suggests that advantage from resources may reside in both the input (resource development) side and the output (resource deployment) side. This research looks at venture survival as a function of both the resources a firm owns, and the resources it can access from others. We focus more specifically on technology resources, which are among a technology-based firm's most critical resources (Itami, 1987). In addition, technological knowledge can contribute a large portion of the value of a firm's products (Goodman and Lawless, 1994). We look at both the input and output side: the pool of technology resources that serve as an input to a firm's activities, and the market that values and purchases the output of this activity. We take an international perspective, examining whether resources explain internationalization on the input and output side, and in turn, whether this internationalization can explain survival. We explore three sets of questions. First, can survival in entrepreneurial firms be explained as a function of the resources a firm owns, and beyond that, to those the firm can access, and still further, to those the firm can access internationally? Second, do resources explain internationalization on both the input and output side? And finally, does internationalization explain survival? Implications for theory include extending the RBV to not only include a firm's resources, but its access to the resources of other entities. In addition, examining internationalization on both the input and output side enables us to understand not just the potential advantage of resources, but the manner in which they are deployed as a source of advantage. This research also contributes to the literature on international entrepreneurship by examining whether internationalization can explain survival for early stage firms. For practitioners, this research will provide insights on the importance of building alliances and, in so doing, broadening an organization's perspective about the technology resources available to the firm on the input side. The study will also inform practitioners about the value of maximizing the market for a firm's valuable resources. In addition, this research provides an extraordinary opportunity to access a large, comprehensive, and longitudinal dataset on technology-based ventures in Korea.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.201-237
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• 1992

본(本) 연구(硏究)는 1992년(年) 2월(月)부터 동년(同年) 8월(月)까지 한국(韓國)의 농어촌진흥공사(農漁村振興公社)(RDC)와 말레시아의 KTA기술용역단간(技術用役團間)의 기술제휴하(技術提携下)에 아세아개발은행(亞細亞開發銀行)의 기술협력기금(技術協力基金)에 의(依)한 말레지아북부(北部) Terengganu 농촌개발제(農村開發第)2단계사업(段階事業)의 타당성조사연구(妥當性調査硏究) 결과(結果) 중 말레시아정부(政府)의 경제정책방향(經濟政策方向), 농업개발(農業開發) 및 사업(事業)의 경제적(經濟的) 재무적(財務的) 타당성(妥當性)만을 발췌(拔萃)하여 본(本) 논문(論文)에 수록(收錄)하였다. 본(本) 농촌개발사업지구(農村開發事業地區)는 말레시아의 북동(北東)쪽에 위치(位置)하고 있는 Terengganu State의 Setiu-Besut양(兩) Distict가 포함(包含)되는데 경제적(經濟的)으로 가장 낙후(落後)된 지역(地域)으로 매년(每年) 행사(行事)처럼 찾아오는 홍수(洪水)때문에 농경지(農耕地)를 집약적(集約的)으로 경작(耕作)하지 못함으로써 지역농민(地域農民)들은 빈곤(貧困)에서 벗어나지 못하고 있고 침수기간중(浸水期間中)에는 지역(地域)의 경제활동(經濟活動)은 물론(勿論) 교통(交通)마저 불통(不通)되고 농촌하부구조(農村下部構造)의 손실(損失)은 물론(勿論) 사회경제적(社會經濟的)인 손실(損失)이 크며 Setiu River의 하구(河口)가 침전(沈澱)되어 어선(漁船)의 출입(出入)이 점점(漸漸) 곤란(困難)해지므로써 어민(漁民)들의 생계(生計)에도 위협(威脅)을 주는 지역(地域)이다. 따라서 본(本) 타당성(妥當性) 조사연구(調査硏究)의 근본적(根本的)인 목적(目的)은 농촌(農村)의 빈곤(貧困)을 타파(打破)하기 위하여 (1) 홍수(洪水)를 방지(防止)하고, 배수(排水) 및 관개개선(灌漑改善)을 하며, 하구(河口)를 개발(開發)하여 어민(漁民)들의 생산활동(生産活動)을 돕고 지역주민(地域住民) 및 농민(農民)들의 경제활동(經濟活動) 및 농업생산성(農業生産性)을 제고(提高)시키며 (2) 환경보호(環境保護) 및 관리(管理)를 통(通)하여 지역주민(地域住民)에게 쾌적(快適)한 농촌생활환경(農村生活環境)을 제공(提供)하고 생태계(生態系)의 변화(變化)를 방지(防止)하며 (3) 다각적(多角的)인 영농활동(榮農活動)을 통(通)하여 지역농민(地域農民)의 소득(所得)을 극대화(極大化) 할 수 있는 개발(開發)의 기본구상(基本構想)과 이에 대한 기술적(技術的) 경제적(經濟的) 타당성(妥當性)을 구명(究明)하는 것이다. 본(本) 사업지역(事業地域)의 총면적(總面積)은 9,500ha이며 이는 4,680ha의 기설지구(旣設地區)의 개보수관개사업(改補修灌漑事業)과 500ha의 과수단지(果樹團地), 200ha의 채소단지(菜蔬團地), 500ha의 옥수수단지(團地), 250ha의 엽연초생산단지(葉煙草生産團地), 2,760ha의 오일팜 및 고무나무단지에 소, 염소 및 양(洋)을 사육(飼育)하는 종합적(綜合的)인 농촌개발(農村開發)로서 농가(農家)의 농업소득제고(農業所得提高)에 큰 기여(寄與)를 하게 되며 Setiu강(江)의 유역(流域) 4,090ha에 대한 홍수경감대책(洪水輕減對策)으로 지역주민(地域住民)의 생활안정(生活安定) 및 교통(交通), 관광(觀光), 사회경제적(社會經濟的) 생산활동(生産活動)을 촉진(促進)하는 사업(事業)을 하게된다. 본(本) 사업(事業)의 공사기간(工事期間)은 1993년(年)부터 5개년간(個年間)이며 총사업비(總事業費)는 외화(外貨) 2천만불(千萬弗)을 포함(包含)하여 5천(千) 5백만불(百萬弗)로 추정(推定)되었다. 년간사업수익(年間事業收益)은 사업(事業)의 완전운영기간(完全運營期間)인 2003년(年)을 기준(基準)으로 할 때 15,541백만불(百萬弗)로 추정(推定)되었으며 사업(事業)의 내구기간(耐久期間)은 30년(年)으로서 2023년(年)까지 생산(生産)이 계속(繼續)될 것이다. 본(本) 사업(事業)의 전체재무수익율(全體財務收益率)은 22.49%이며 경제적(經濟的) 수익률(收益率)은 19.30%로 경제적(經濟的)인 타당성(妥當性)이 매우 높음을 알 수 있다. 모든 사업(事業)이 계획(計劃)대로 성공적(成功的)으로 추진(推進)될 경우 사업지역내(事業地域)의 몽리농가(蒙利農家) 4,000호(戶)가 큰 혜택(惠澤)을 보게되고 농촌(農村)의 빈곤수준(貧困水準)(Poverty Line)은 현재(現在)의 36%에서 18%수준(水準)으로 경감(輕減)될 것이 기대(期待)되고 있다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.483-494
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• 2019

From the cosmopolitan superiority of the as the first world map completed in 1402 with surprisingly detailed images and contents on the Africa Continent it is reasonable to think that the Koreans in early fifteen century were already with highly up-to-date perspectives on the universe and world history and cultures. However, some 490 year later the first phytohydrographic plankton investigation in the neritic seas of Korea was performed by a Japanese company with sampling points covering from Tokyo Bay through Jeju neritic waters to Shanghai estuary, which was in turn preceded by the first oceanographic investigation other than the simple mapping Koreans seas by using two French sailboats. The first phytohydrographic plankton investigation in Korean seas were behind the world first oceanic plankton exploration, the German Plankton Expedition, by 25 years. Starting from the oceanographic investigation including phytohydrographic samplings in the whole Yellow Sea in 1915 the full-scale phytohydrographic plankton studies were tried in Korean seas which is well represented by the 1921 oceanographic investigation on the whole East Sea with 80 sampling stations. In 1932 two separate oceanographic investigations followed, one in the East Sea where 78 stations from Busan to southern Sakhalin Island were simultaneously visited by 50 research vessels for the physical, chemical, and biological oceanographic studies, and the other one in southern coast and western East Sea of Korea where ocean current observation as well as plankton sampling were made in 120 stations to understand the relationship between the ocean current and plankton distribution in the region. In 1933-1934 more intensified investigations on phytohydrography were carried out particularly in the East Sea as an integral part of the basic marine ecosystem studies for the Myeong-Tae (Alaska Pollock) resources estimation. Scientists' attitude for the marine investigation and research activities seemed to be almost unchanging even to the year 1943, which could be reflected by the fact that publication of the results from the investigations performed in 1945 were finally done in 1967 at Tokyo. Some 70 years later from the mid-twenty century we might be standing on the turning-point of "need to be prepared" for the new era of changing paradigm by reviewing, archiving, and analyzing the prior information big data from the previous ocean observation and biohydrographic investigations. At the same time each professional societies for the above mentioned sciences might trigger a continuous project to reorganize and update the records on related bibliography and its history every 30 years.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.175-186
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• 2019

Efforts have been made to introduce the climate smart agriculture (CSA) for adaptation to future climate conditions, which would require collection and management of site specific meteorological data. The objectives of this study were to identify requirements for construction of agricultural meteorology information service system (AMISS) using technologies that lead to the fourth industrial revolution, e.g., internet of things (IoT), artificial intelligence, and cloud computing. The IoT sensors that require low cost and low operating current would be useful to organize wireless sensor network (WSN) for collection and analysis of weather measurement data, which would help assessment of productivity for an agricultural ecosystem. It would be recommended to extend the spatial extent of the WSN to a rural community, which would benefit a greater number of farms. It is preferred to create the big data for agricultural meteorology in order to produce and evaluate the site specific data in rural areas. The digital climate map can be improved using artificial intelligence such as deep neural networks. Furthermore, cloud computing and fog computing would help reduce costs and enhance the user experience of the AMISS. In addition, it would be advantageous to combine environmental data and farm management data, e.g., price data for the produce of interest. It would also be needed to develop a mobile application whose user interface could meet the needs of stakeholders. These fourth industrial revolution technologies would facilitate the development of the AMISS and wide application of the CSA.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.188-197
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• 2020

Termites play an important role as decomposers of the forest ecosystem, while simultaneously causing enormous damage to wooden structures. Currently, two species of subterranean termites have been reported in Korea, and termite damage to historical wooden buildings is occurring nationwide due to climate change, forest fertility, and the locational characteristics of historical wooden buildings. Subterranean termites make their nests underground or inside timber. Termites move underground and access wooden structures through the lower parts of the buildings, adjacent to the ground. Once termites attack the wooden structures, it not only spoils the authenticity of cultural heritage structure, but also hampers structural stability due to the decrease in the strength of the material. Therefore, it is important to prevent termite damage before it occurs. Chemical treatments are mainly used in Korea to control and prevent the damage. In foreign countries, physical barriers are also used to prevent entry to wooden buildings, along with chemical treatments. Physical barriers involve installing nets or particles that termites cannot pass through in the lower part of the building, around the pipes, and between the edges of the building or exterior walls and interior materials. Advantages of a physical barrier are that it is an eco-friendly method, maintains long-term effect after installation, and does not require the use of chemical treatments. Prior to applying physical barriers, studies into the characteristics of termite species must be undertaken. In this study, we evaluated the minimum passage size that each caste of Reticulitermes speratus kyushuensis can move through. We found that workers, soldiers, and secondary reproductive termites were able to pass through diameters of 0.7mm, 0.9mm, and 1.1mm respectively. Head height of termites was an important factor in determining the minimum passing size. Results from the current study will be used as a basis to design the mesh size for physical barriers to prevent damage by termites in historical wooden buildings in Korea.