• Korean Journal of Weed Science
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• v.15 no.4
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• pp.305-312
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• 1995

Weed communities in the dry-direct seeded rice(Oryza sativa L.), soybean(Glycine max(L.) Merr.), and dry-direct seeded rice-soybean rotation system from the transplanted rice field were investigated in order to identify a change in weed species by paddy-upland rotation. Echinochloa species was the most dominant species in the dry-direct seeded rice and their great increase was observed in the continued practices of dry-direct seeded rice. Echinochloa spp., Chenopodium ficifolium, and Digitaria spp. were identified as the major weeds in soybean cultivation in paddy field. Practice of soybean rotation in the dry-seeded rice reduced weed occurrence, particularly at the soybean after 2-yr continued dry-direct seeded rice and at dry-direct seeded rice culture after 2-yr continued dry-direct seeded rice and at dry-direct seeded rice culture after 2-yr soybean compared to the continued cultures of rice or soybean. In addition, cultivation of dry-direct seeded rice or soybean culture in the paddy rice field seemed to be helpful for suppression of perennial weeds(Eleocharis kuroguwai, Cyperus serotinus, Scirpus juncoides) and aquatic weeds(Monochoria vaginalis, Sagittaria spp. Potamogeton distinctus).

• Korean Journal of Weed Science
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• v.15 no.1
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• pp.1-12
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• 1995

These researches have been conducted to obtain the basic information of the effects of paraquat on plant species and to screen the plant species showing specific responses to paraquat. Paraquat resistance related to ecotype and overwintering capacity. Perennial and biennial species showed higher resistance than annual species. In a family, most species showed higher resistance were overwintering species. Lamiaceae, Brassicaceae, and Caryophyllaceae were tolerant to paraquat, whereas Poaceae and Asteraceae were sensitive. Especially Mosla dianthera of Lamiaceae, Hemistepta lyrata and Aster pilosus of Asteraceae, and Paspalum thunbergii of Poaceae showed higher tolerance than others. The response patterns of plant species on germination stage were different to those on vegetative stage. Germination of Amarathus lividus, Arabis glabra, and Bidens frondosa was not inhibited by paraquat. But their seedling growth were highly inhibited.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.225-229
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• 2015

Echinochloa colona is one of the most problematic weeds in the paddy fields of the world. In recent years, this species is likely to be introduced in Korea due to global warming, the expansion of international trade including agricultural products, and increasing tourists. We tried to identify the species from Korean Echinochloa crus-galli and E. oryzicola in order to establish the control measures in case of the initial influx. For this study, Echinochloa colona collected from the National Plant Germplasm System, USA were examined and E. crus-galli and E. oryzicola were collected in Korea. It is, however, very difficult to identify for Echinochloa species using morphological characters because of numerous interspecific and intraspecific types found in nature. Thus, we barcoded the species using rbcL, matK, and ITS. All three markers identified E. colona very well from the others. ITS alone may be enough as a DNA barcode for E. colona identification, when considering cost and effectiveness. The barcode sequences were deposited to the National Center for Biotechnology Information database for public use.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.122.2-122.2
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• 2011

For more than a decade, NEA (Near-Earth Asteroid) survey teams equipped with 1 meter-class telescopes discovered thousands of NEAs in the northern sky. As of August 2011, some 8,200 NEAs have been cataloged, yet only five percent of them has been investigated for their physical and chemical properties. In order to improve current situation, we propose a deep ecliptic survey utilizing KMTNet, for detection and characterization of NEAs in the southern sky. Thanks to the wide-field capability (four square degrees) of the telescopes, we will be able to considerably expand the search volume carrying out precision photometry down to 21.5th magnitude. We plan to focus our survey on opposition and two "sweet spots" in the ecliptic belt. Since SDSS colors characterize mineralogical properties of NEAs, g', r', i', z' filters will be employed. Based on the round-the-clock observation, we will study their rotational properties; for multiple systems, mass, density and other physical parameters can be obtained. We plan to maintain a dedicated database of the physical and mineralogical properties of NEAs. With this archive, it is expected that our understanding on the population will see a drastic change. We also plan to participate in the GAIA Follow-Up Network for ground based observation of the Solar System Objects (GAIA-FUN-SSO). The follow- up astrometry will be performed upon alerts issued by the GAIA-FUN-SSO Central Node in France.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.7
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• pp.190-200
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• 2014

The video-based system of the broadcasters and the video-related institutions have shifted from analogical to digital in worldwide. This migration process can generate a defect, digital dropout, in the quality of the contents. Moreover, there are limited researches focused on these kind of defects and those related have limitations. For that reason, we are proposing a new method for feature extraction emphasizing in the peculiar block pattern of digital dropout based on discrete cosine transform (DCT). For classification of error block, we utilize support vector machine (SVM) which can manage feature vectors efficiently. Further, the proposed method overcome the limitation of the previous one using continuity of frame by frame. It is using only the information of a single frame and works better even in the presence of fast moving objects, without the necessity of specific model or parameter estimation. Therefore, this approach is capable of detecting digital dropout only with minimal complexity.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.8
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• pp.37-44
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• 2004

This paper describes a new GaAs-based surface-micromachined microstrip line supported by dielectric post and air-gapped signal line with ground metal. This new type of dielectric-supported air-gapped microstripline(DAML) structure is developed using surface micromachining techniques to provide easy means of airbridge connection between the signal lines and to archive low losses at millimeter-wave frequency band with wide impedance range. Each DAMLs with the length of 5 mm are fabricated and the measured characteristics are compared with those of the conventional microstrip transmission line. These transmission lines are composed of 10 ${\mu}{\textrm}{m}$ height of signal line, post size of 10 ${\mu}{\textrm}{m}$ ${\times}$ 10 ${\mu}{\textrm}{m}$ and post height of 9 ${\mu}{\textrm}{m}$. By elevating the signal lines from the substrate using the micromachining technology, the substrate dielectric loss can be reduced Compared with of the conventional microstrip transmission line showing 7.5 dB/cm loss at 50 GHz, the loss can be reduced to 1.1 dB/cm loss at 50 GHz.

• Korean Journal of Weed Science
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• v.16 no.3
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• pp.171-175
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• 1996

Seed occurrence patterns of Echinochloa crus-galli (L) P. Beauv. and Monochoria vaginalis (Burm. f.) Presl. were investigated in irrigated and rainfed rice cultures. There was not much difference in seed population of E. crus-galli between irrigated and rainfed fields, but M. vaginalis occurred in about 1.6-fold greater number in rainfed fields. In seed distribution patterns under the two conditions, about 50% and 30% of E. crus-galli and M. vaginalis, respectively, were found in the uppermost 5cm layer. Under both conditions M. vaginalis was distributed to a depth of 25cm, but distribution of E. crus-galli was only 15cm deep. Early rice transplanting brought about greater emergence of the two weeds than optimal or late transplanting. Emergence of the weeds was significantly greater in single cropping system of rice than in double cropping systems of rice followed by barley and/or strawberry.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.28 no.4
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• pp.437-460
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• 2017

After introducing the Industrial Trainee System in 1993, the population of immigrants coming to Korean have increased rapidly and over 2 million immigrants are living in Korea in 2017. In this situation, libraries are responsible for collecting, organizing, preserving and disseminating various records related to immigrants living in local communities but it is hard to find these kind of libraries in Korea. So, this study is trying to investigate the characteristics of multicultural archives established by libraries in other countries. To do this, 9 multicultural archives in U.S. and Canada were analyzed in terms of participating institutions and supporting institutions, types of records, digitizing and file formats, digital collection management systems and metadata schemas. At last, some suggestions were proposed to improve the function of libraries as a local multicultural archives.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.30 no.4
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• pp.235-254
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• 2019

According to the development of information technology, the paradigm of the archives is shifting from preservation management of past records to use-oriented services. In this regard, this study is conducted an empirical study on the effect of internal marketing factors of university archives on the customer orientation of employees in order to improve organizational satisfaction for users of records information service. Based on the previous research, the delegation of authority, internal communication, management support, and training are established as factors of internal marketing, and the parameters for this are job satisfaction, organizational commitment, customer orientation as dependent variables, and We set up hypothesis between research variables and attempted an analysis through statistical system. In summary, each element of internal marketing showed significant results on job satisfaction and organizational commitment, and management support was most closely related to job satisfaction, organizational commitment, and customer orientation of university archive staff.

• Journal of the Institute of Convergence Signal Processing
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• v.3 no.1
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• pp.33-40
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• 2002

In this paper, we proposed a lossless compression algorithm of medical images which is essential technique in picture archive and communication system. Mammographic image and magnetic resonance image in among medical images used in this study, proposed a region growing segmentation algorithm for compression of these images. A proposed algorithm was partition by three sub region which error image, discontinuity index map, high order bit data from original image. And generated discontinuity index image data and error image which apply to a region growing algorithm are compressed using JBIG(Joint Bi-level Image experts Group) algorithm that is international hi-level image compression standard and proper image compression technique of gray code digital Images. The proposed lossless compression method resulted in, on the average, lossless compression to about 73.14% with a database of high-resolution digital mammography images. In comparison with direct coding by JBIG, JPEG, and Lempel-Ziv coding methods, the proposed method performed better by 3.7%, 7.9% and 23.6% on the database used.