• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.200-207
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• 2006

The objective of this study was to investigate the site and growth characteristics of Acer pictum var. mono growing in the deciduous stands at Mt. Joongwang area located in Pyungchanggun, Kangwon-do. A. pictum var. mono was mainly distributed at the rather steep slope and aspect facing from northeast to northwest, and altitudes ranging from 1,000 to 1,200m. It grew at relatively deep a soil layer with high moisture and nutrients. Major competing species in the upper stories were Betula costata, Acer mandshuricum, Quercus mongolica, Cornus controversa, and herb plants such as Meehania urtidfolia, Isodon excisus, Astilbe chinensis var. davidii, Dryopteris crassirhizoma and Ainsliaea acerifolia in the floor. The height growth was 0.25m in early time, decreased gradually and sustained growth of lower than 10cm. The diameter growth of A. pictum was under 1mm in early time, but increased to 0.3mm/yr and showed continuous growth of 2mm/yr recently. Annual volume growth showed rapid increased about age 120 and then showed stable growth, so the rotation period of A. pictum is expected more than 200 years without decay of heartwood.

• Korean Journal of Environment and Ecology
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• v.12 no.1
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• pp.30-41
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• 1998

This study analyzed urban greenspace area and vegetation structure by land use types for Kangnam-gu and Junglang-gu in Seoul different in income and building construction date. The study districts had a similar areal distribution of land use types. Residential lands accounted for about 32~37% of total area, natural lands, 19~22%, commercial and industrial lands(including transportation), 13~18%, and institutional lands, 13~17%. Greenspace covered only 20~30% of urban residential and commercial area in which human activities of living concentrate. Canopy stocking level in urban lands (all land uses except natural and agrecultural lands) was about 39% for Kangnam-gu and 50% for Junglang-gu, showing tree planting potential slightly higher in Kangnam-gu than in Junglang-gu. Woody plant cover was approximately 13%, and tree density was 3 trees/100m$^{2}$ forurban lands in both districts. The tree-age structure was largely characterized by young, growing tree population, and species diversity within a diameter class decreases as the diameter classes get larger. Urban lands of both districts had quite a similar species composition of woody plants (similarity indez of 0.70). Income and bulding construction date did not result in significant diference between the two districts in vegetation structure for urban lands. Some strategies were ezplored to solve problems found in the present greenspace structures. They included increase of biomass and greenspace area through minimization of unnecessary impervious surfaces, creation of multilayered and multiaged vegetation structures, and avoidance of intensive tree pruning and relocation of above ground utility lines.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.1
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• pp.23-37
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• 2011

This paper is brought to carry out an empirical study whether evolution process of venture firm's scale is following the Gibrat's law; random evolution process, or Pareto law; self-organizing process. The empirical test, as attaching theoretical explanation, of this research utilize the serial data samples of 92 KOSDAQ listed companies from the year of 2005 through 2008. Summarizing the research results are as followed. First, Gini Coefficients representing the density of venture firm's scale has been constantly reduced since the year of 2005 in terms of number of employee, while these index increased during the same time period from the perspective of sales volume. Second, the evolution process of Korea venture firm's scale is following the Power Law related to Pareto Law. In particular, estimated Pareto coefficient, ${\alpha}$, is shown lower than 1 which is significant result. Third, the probability of joining in the top tier group of firm starting from the early stage growing is forecasted into 6.9%, the result which emphasize the starting scale of venture firm play an important role in long term evolution of venture firm.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.74-81
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• 1984

The experiments were conducted to study the distribution of wilt of strawberry caused by Fusarium in Korea, the characters of the causal fnngus and its control. The results obtained are summarized as follows. 1. Wilt of strawberry has been found in Gimhae and Samrangjin, Gyeongnam province a few years ago. This disease has been spreading year after year, and observed on farms in most of the strawberry-growing areas in Korea. 2. The fungus was isolated frequently from the crowns and petioles of diseased straw berry plants, and the fungus belonging to Fusariun oxysporum in terms of the morphological characteristics of macroconidia, microconidia, chlamydospore and conidiophore on V-8 Agar. 3. The macroconidia formation of the fungus varied remarkably with the Isolates and kinds of medium tested. However. all isolates abundantly produced macroconidia on V-8 Agar. 4. The cross-inoculation tests with several forma specialis of F. oxysporum to cucumber, tomato, watermelon, luffa, cabbage, melon and strawberry were carried out. The isolates from strawberry viz. Kodama's F. oxysporum f. sp. fragariae and S-1 of the authors were pathogenic to only strawberry. The fungus was also similar in morphology and symptoms to Kodama's and Winks' isolate of F. oxysporum f. sp. fragariae. Therefore, the fungus is identified as Fusarium oxysporum Schl. f. sp. fragariae Winks & Williams. 5. The most effective fungicides were Benomyl and Homai for inhibiting sporulation and mycelial growth of the fungus. 6 The cultivar Kurumae 35, Himiko, Senga gigana and Daehak I were resistant, whereas Hokowase, Instiate Z4, Juspa, Puget beauty and Marshall were susceptible to the fungus with artificial inoculation.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.422-433
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• 2017

Unmanned Aerial Vehicle (UAV) has several advantages over conventional remote sensing techniques. They can acquire high-resolution images quickly and repeatedly. And with a comparatively lower flight altitude, they can obtain good quality images even in cloudy weather. In this paper, we developed for estimating garlic growth at field scale model in major cultivation regions. We used the $NDVI_{UAV}$ that reflects the crop conditions, and seven meteorological elements for 3 major cultivation regions from 2015 to 2017. For this study, UAV imagery was taken at Taean, Changnyeong, and Hapcheon regions nine times from early February to late June during the garlic growing season. Four plant growth parameters, plant height (P.H.), leaf number (L.N.), plant diameter (P.D.), and fresh weight (F.W.) were measured for twenty plants per plot for each field campaign. The multiple linear regression models were suggested by using backward elimination and stepwise selection in the extraction of independent variables. As a result, model of cold type explain 82.1%, 65.9%, 64.5%, and 61.7% of the P.H., F.W., L.N., P.D. with a root mean square error (RMSE) of 7.98 cm, 5.91 g, 1.05, and 3.43 cm. Especially, model of warm type explain 92.9%, 88.6%, 62.8%, 54.6% of the P.H., P.D., L.N., F.W. with a root mean square error (RMSE) of 16.41 cm, 9.08 cm, 1.12, 19.51 g. The spatial distribution map of garlic growth was in strong agreement with the field measurements in terms of field variation and relative numerical values when $NDVI_{UAV}$ was applied to multiple linear regression models. These results will also be useful for determining the UAV multi-spectral imagery necessary to estimate growth parameters of garlic.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.6
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• pp.89-98
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• 2005

Fingerprint segmentation and ridge orientation estimation algorithms with images from a mobile camera are proposed. The fingerprint images from a mobile camera are quite different from those from conventional sensor, called touch based sensor such as optical, capacitive, and thermal. For example, the images from a mobile camera are colored and the backgrounds or non-finger regions are very erratic depending on how the image capture time and place. Also the contrast between ridge and valley of a mobile camera image are lower than that of touch based sensor image. To segment fingerprint region, we first detect the initial region using color information and texture information. The LUT (Look Up Table) is used to model the color distribution of fingerprint images using manually segmented images and frequency information is extracted to discriminate between in focused fingerprint regions and out of focused background regions. With the detected initial region, the region growing algerian is executed to segment final fingerprint region. In fingerprint orientation estimation, the problem of gradient based method is very sensitive to outlier that occurred by scar and camera noise. To solve this problem, we propose a robust regression method that removes the outlier iteratively and effectively. In the experiments, we evaluated the result of the proposed fingerprint segmentation algerian using 600 manually segmented images and compared the orientation algorithms in terms of recognition accuracy.

• Journal of Korea Port Economic Association
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• v.34 no.2
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• pp.97-114
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• 2018

The East Asian region, an important part of Korea's imports and exports, is expected to grow further driven by the geographical, political, economic, social, and cultural complementarity. With the recent increase in imports and exports, the port trade volume between Korea and East Asian countries is also growing. However, due to various factors, such as economic size, growth rate, port infrastructure level, and geographical location of these countries, the volume of traffic with these ports is fluctuating. Despite much research on the volatility of port trade volume and changes in port network, this study tries to supplement the gap in a more detailed study of ports in Korea and East Asia since these kinds of studies are limited. The purpose of this study is to analyze the trend of distribution routes of export container cargo among ports in Korea and to present policy and practical implications of Korean trading companies, shipping companies, logistics companies, and port authorities. This study analyzes the variability of the trade volume between Korea's major ports and Daedong. Results show that Shanghai, Ningbo, Ho Chi Minh, and Haiphong were the most important factors in terms of size and volume increase. In terms of ports, the Busan port is the port responsible for trades with Yantai, Weihai, Hakata, Kobe, Ho Chi Minh, and Haiphong; Incheon port deals with Lianyungang, Tianjin, Osaka, Kobe, Ho Chi Minh, Haiphong; Gwangyang port trades with Tianjinxingang, Weihai, Yokohama, Mihn and Tanjong, and Ulsan port is strategically important for the Yantai, Lianyungang, Nagoya, Kobe, Ho Chi Minh and Portkelang ports. Therefore, the Korean government, port authorities, and shipping and logistics companies need to strengthen logistic network cooperation with these ports and actively promote investments in them.

• Journal of Wetlands Research
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• v.17 no.4
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• pp.359-369
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• 2015

Stream ecosystems are highly valued natural resources, however, stream environments are currently under threat in several respects. We evaluated vegetation and ecological characteristics according to different revetment types. The distribution of vegetation differed with revetment type, with a 42~45 taxa found in natural revetments, and 23~38 taxa in vertical revetments. Thus, natural revetments host more diverse vegetation than vertical revetments. We also found more plants belonging to the families Labiatae and Cyperaceae growing in natural revetments than in vertical revetments. We proposed that habitat space be apportioned to introduce annual plants as part of stream restoration projects. And, we identified 7 families and 18 taxa of naturalized plants, majority taxa were either biennial or perennial. Moreover, naturalized ratio was higher in vertical(14.3%) than natural(12.1%), we proposed a plan to promote and improve natural streams and revetments. Furthermore, we applied a waterfront evaluation method developed by the Natural Resources Conservation Service of the USDA-NRCS, which confirmed that stream health can be improved in most regions by controlling naturalized plants and ensuring shrub and tree growth. We adopted a new method to remove naturalized plants and establish natural revetments to ensure shrub and tree growth to aid in small-stream restoration and improvement. In future studies, we hope to develop methods for small-stream restoration projects in rural areas.

• Journal of Life Science
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• v.27 no.9
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• pp.1086-1095
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• 2017

There is growing interest in groundwater resources to overcome the loss of surface water resources due to climate change. An understanding of the microbial community of aquifers is essential for monitoring and evaluating groundwater contamination, as well as groundwater management. Most microorganisms that inhabit aquifer ecosystems are attached to sediment particles rather than planktonic, as is the case in groundwater. Since sampling aquifer sediment is not easy, groundwater, which contains planktonic microorganisms, is generally sampled in microbial community research. Although many studies have investigated microbial communities in contaminated aquifers, there are only a few reports of microbial communities in uncontaminated or pristine aquifers, resulting in limited information on aquifer microbial diversity. Such information is needed for groundwater quality improvement. This paper describes the ecology and community structure of groundwater bacteria in uncontaminated aquifers. The diversity and structures of microbial communities in these aquifers were affected by the concentration or distribution of substrates (e.g., minerals, organic matter, etc), in addition to groundwater characteristics and human activities. Most of the microbial communities in these uncontaminated aquifers were dominated by Proteobacteria. Studies of microbial communities in uncontaminated aquifers are important to better understand the biogeochemical processes associated with groundwater quality improvement. In addition, information on the microbial communities of aquifers can be used as a basis to monitor changes in community structure due to contamination.

• Korean Journal of Environmental Agriculture
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• v.6 no.2
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• pp.22-30
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• 1987

Maize plants, grown on a German soil and a Korean soil which had treated with benzene-ring-labelled $^{14}C-Bentazon$ (5.02mg/kg) immediately before planting (T-0), took up $36.0{\sim}42.8%$ of the radioactivity present during a 21 day growing period. Plants grown on the same soils $(4.79{\sim}4.84mg/kg)$ which had been treated with Bentazon and pre-incubeted for 105days absorbed $8.2{\sim}14.2%$ (T-1) of the radioactivity. Plants grown in soils $(5.56{\sim}7.95mg/kg)$ treated with Bentazon which had been incubated for 105 days and then exhaustively extracted with distilled water and/or 0.01 M $CaCl_2$ to produce non-extractable residues (T-2) took up $1.8{\sim}2.3%$ of the radioactivity. The distribution of the absorbed radioactivity ranged from 2.7 to 9.7% in shoots and from 90.3 to 97.3% in roots. Extraction of maize roots revealed that $39.1{\sim}51.3%$ of the radioactivity was bound in T-0 and $55.7{\sim}63.1%$ was bound in T-1, This suggests hat polar metabolites and parent Bentazon might be present as conjugates.