• Journal of Korean Society on Water Environment
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• v.24 no.2
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• pp.206-213
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• 2008

Fish fauna and community structure were investigated at 2003, 2004 and 2006 in Lake Paldang and its inflows. In this survey, we collected 54 species belong to 14 families. Family Cyprinidae take 51.9% (28 species), Cobitidae and Gobiidae occupied 7.4% (each 4 species), respectively. E. erythropterus (11.8%) was dominant species and L. macrochirus (10.2%), designated as an ecosystem-invasive alien fish species by Ministry of Environment, M. yaluensis (9.1%), Z. platypus (7.7%) and R. brunneus (6.7%) were dominated in turn. H. molitrix, C. lutheri, P. altivelis, S. microdorsalis, L. costata. S. gracilis majimae, A. rivularis, P. koreanus. S. scherzeri and O. platycephala were rare species (less than 0.1% in relative abundance). In-lake area, 36 species of fishes belonging to 11 families were collected, and 48 species of 13 families were from inflows. The number of Korean endemic species were 19 species (35.2%), and 4 kinds of exotic species (7.4%), that is, C. cuvieri, H. molitrix, L. macrochirus and M. salmoides were found at this survey area. It was revealed by the analysis of fish community that diversity and richness indices were prominent at tributaries, and dominance index was high at the main body of Lake Paldang. Fish fauna showed rapid decline after dam construction which make the mid-Han river systems to lentic ecosystem, so many of meander-riffle fishes were disappeared dramatically. But after 1990s when installation of small scale wastewater treatment plants started in watershed, the water quality of small tributaries was improved. And also, expansion of the natural macrophytic vegetation of littoral zone should contribute to the development of diverse fish fauna in Lake Paldang.

• Journal of the Korean Ceramic Society
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• v.30 no.4
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• pp.289-298
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• 1993

Properties in terms of the variation of the glass compositions, which were density (p), molar volume(Vm), atom/ion packing density (Dp), refractive index (nD), transformation temperature (Tg), dilatometric softening point (Td), thermal expansion coefficient (α), Young's modulus (E), and knoop hardness (KHN) were investigated in CaO-SiO2 glasses and CaO-P2O5-SiO2 glasses containing less than 10mole% of P2O5. Those properties were measured by density measurement kit, Abbe refractometer, dilatometer, ultrasonic pulse echo equipment, and micro hardness tester. When CaO content was increased in CaO-SiO2 glasses, p, Dp, nD, Tg, Td, α, E and KHN were increased, while Vm was decreased. When P2O5 was added to the CaO-SiO2 glasses with constant CaO/SiO2 ratio as 1.07, p, Dp, nD, Tg, Td, α, E and KHN were decreased, while Vm was increased. When the amount of P2O5 in glasses was kept constant, the changes of the properties with variation of CaO content in the CaO-P2O5-SiO2 glasses were very similar to those of CaO-SiO2 glasses. These phenomena could be explained by the structural role of P2O5 in the CaO-P2O5-SiO2 glasses, which was polymerization of siicate structures and resulted in [PO4] monomer structure in glasses. Due to this structural characteristics, the bond strength and packing density were changed with compositions. Proportional relationships between 1) np and Dp, 2) Tg, Td, α and CaO content, 3) E and Vm-1, and 4) KHN and P2O5 content were evaluated in this investigation.

• Journal of Korean Library and Information Science Society
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• v.13
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• pp.85-111
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• 1986

Dewey Decimal Classification (DDC) was first published in 1876. Since its first edition it has been revised, on an average, 6 years, and now it has become the widely used library classification system of which the scheme was translated in various languages. The purpose of this study is to find out the chief causes for the development of the DDC. The results of the study can be summarized as follows: 1. It allows materials to be shelved in a relative location as the collection expands. before the DDC was introduced, libraries used a fixed location for materials in which each item was assigned to a certain location set aside for a subject. 2. It is a practical system. The fact that it has survived many storms in the past hundred years and is still the most widely used classification scheme in the world today attests to its practical value. 3. The pure notation of arabic numerals is universally recognizable. People from any cultural or language background can adapt to the system easily. 4. The use of the decimal system enable infinite expansion and sub-division. And it has adaptability for use in libraries of various size and kinds because of its hierarchically expressive notation which permits varying degrees of inclusiveness and exclusiveness within its decimal structure. 5. The notation is simple and easily understood. The self-evident numerical sequence facilitates filing and shelving. And the mnemonic nature of the notation helps the readers to memorize and recognize the class numbers. 6. The relative index brings together different aspects of the same subject scattered in different disciplines. 7. We can avail of DDC numbers for specific titles easily because of its use by many central bibliographic services. 8. It is being continuously revised by a permanent office established in the library of congress in 1933. This office has been responsible for editing all editions of the DDC since the 16th (1958). And the periodic revision at regular intervals ensures the currentness of the scheme. 9. It has adaptability both for conventional (manual) shelf or classed catalogue analysis and also, through its meaningful nation, for retrieval through mechanization and computerized systems.

• The Journal of the Korea Contents Association
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• v.10 no.7
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• pp.449-458
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• 2010

The e-Learning quality assurance is a part of responsibility for education in latest information age, and should be understood as a basic direction for qualitative enhancement rather than quantifiable expansion. In such a context, this study sought to survey latest trends of e-Learning quality assurance activities deployed around overseas countries, so that it could give possible implications on how to plan and perform e-Learning quality assurance in Korea. So, this study focused on surveying actual conditions, coverage, target and useful indices of e-Learning quality assurance activities deployed by 9 institutions across 5 countries, and characterizing those activities across 5 countries. As a result, this study could find out its implications such as acquisition of various resources available for e-Learning, nationwide consolidation of e-Learning quality assurance activities, development of specialists in e-Learning quality assurance, and choice and focus for e-Learning quality assurance system. In other words, it was found that e-Learning quality assurance should be approached from nationwide standpoint in the interest of better educational quality, rather than from viewpoint of task.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.333-333
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• 2006

We synthesized two novel polynorbornene derivatives, chiral poly(norbornene acid methyl ester) (C-PNME) and racemic poly(norbornene acid n-butyl ester) (R-PNME), which are potential low dielectric constant materials for applications in advanced microelectronic and display devices. Thin films of these polymers deposited on substrates were investigated by structural analyses using synchrotron grazing incidence X-ray scattering, specular reflectivity and ellipsometry. These analyses provided important information on the structure, electron density gradient across film thickness, chain orientation, refractive index and thermal expansion of the polymers in substrate-supported thin films. The structural characteristics and properties of the thin films were first dependent on the polymer chain' tacticity and further influenced by film thickness and thermal annealing.

• Journal of Digital Convergence
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• v.18 no.11
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• pp.43-49
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• 2020

The purpose of this study was to analyze factors affecting the housing market by setting household loans and M2, which are liquidity indicators, and the industrial production index reflecting economic fluctuations, as variables, and to determine the effect of expected housing prices. An empirical analysis was conducted based on the data from January 2005 to May 2020, and the HP filter was applied to the real house price as the expected house price variable. As a result of the analysis, it was found that real household loans, real M2, and so on, had an effect on house prices, and expectations for past house prices and house prices increased the house prices in the present period. These results show that even though the liquidity expansion is aimed at revitalizing the economy, it can affect housing prices as well.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.25 no.3
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• pp.101-118
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• 2014

Given the context of rapid developing ubiquitous computing environment, it is imperative for users to search and use images based on affective meanings. However, it has been difficult to index affective meanings of image since emotions of image are substantially subjective and highly abstract. In addition, utilizing low level features of image for indexing affective meanings of image has been limited for high level concepts of image. To facilitate the access points of affective meanings of image, this study aims to utilize user-provided responses of images. For a data set, emotional words are collected and cleaned from twenty participants with a set of fifteen images, three images for each of basic emotions, love, sad, fear, anger, and happy. A total of 399 unique emotion words are revealed and 1,093 times appeared in this data set. Through co-word analysis and network analysis of emotional words from users' responses, this study demonstrates expanded word sets for five basic emotions. The expanded word sets are characterized with adjective expression and action/behavior expression.

• Journal of The Korean Astronomical Society
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• v.47 no.6
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• pp.259-277
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• 2014

G192.8-1.1 has been known as one of the faintest supernova remnants (SNRs) in the Galax until the radio continuum of G192.8-1.1 is proved to be thermal by Gao et al. (2011). Yet, the nature of G192.8-1.1 has not been fully investigated. Here, we report the possible discovery of faint non-thermal radio continuum components with a spectral index ${\alpha}{\sim}0.56(S_{\nu}{\propto}{\nu}^{-{\alpha}})$ around G192.8-1.1, while of the radio continuum emission is thermal. Also, our Arecibo $H_I$ data reveal an $H_I$ shell, expanding with an expansion velocity of $20-60km\;s^{-1}$, that has an excellent morphological correlation with the radio continuum emission. The estimated physical parameters of the $H_I$ shell and the possible association of non-thermal radio continuum emission with it suggest G192.8-1.1 to be an~0.3 Myr-old SNR. However, the presence of thermal radio continuum implies the presence of early-type stars in the same region. One possibility is that a massive star is ionizing the interior of an old SNR. If it is the case, the electron distribution assumed by the centrally-peaked surface brightness of thermal emission implies that G192.8-1.1 is a "thermal-composite" SNR, rather than a typical shell-type SNR, where the central hot gas that used to be bright in X-rays has cooled down. Therefore, we propose that G192.8-1.1 is an old evolved thermal-composite SNR showing recurring emission in the radio continuum due to a nearby massive star. The infrared image supports that the $H_I$ shell of G192.8-1.1 is currently encountering a nearby star forming region that possibly contains an early type star(s).

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.1
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• pp.128-141
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• 1996

The pourpose of this study is to determine the exact size which can be the basic elements of the fashion design with the measurement of middle-aged women's body, and to grasp the peculiar tomato type of the middle-aged women by compacting each measurement and examing the change of body shape. Making 215 house wives about 40 to 55 years old the subject of this research, we measured the body size from June to August, 1994. After analyzing the data through the 43 item.; of the body measurement, grasping the characteristics of the tomato type, we classified three types of physical standard and looked into the element of body structure. The results were as follows; 1. The average Rohrer index of middle-aged women in Tas-gu is about 1.5 and they usually seem to be fat compared with other groups. 2. Age has much influence on the body change of middle-aged women. Especially around 45 years old, the body change showed remarkable. 3. When analyzing the elements of the body measurement, the biggest elements of middle -aged women's body structure are in the items of width, thickness and girth related to the expansion of body line. Therefore in the middle age, the thickness and the girth have more influence on the human body than the height and the length, so the items of thickness and girth is the most important factor in the somato type. 4. In the slim body and standard body, the thirst factor is the items of height and length related to vertical size and the second is the items of width and thickness and girth. In ice fat body the first factor is the items of width, thickness, girth and the second is those of height, length. Unlike other body shapes, the fat body has many factors, which shows that the fat body has much variation in each part in proportion to fatness.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.181-181
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• 2017

Global warming and climate change have been one of the most important problems last 2 decades. Global warming is known to cause abnormal climate and influence ecology, food production and human health. According to climate change model global warming is causing expansion of drought and increase of evaporation. Therefore, securing water in agriculture has been an important issue for crop cultivation. As potato is susceptible to drought, water shortage generally results in decrease of yield and decrease of biomass. In this research, we investigated characteristics of inorganic nutrient absorption and growth of plants grown under drought condition. Plants were sampled in sites of Cheong-ju and Gangneung, where the severity of drought stress were different. During the growth period in Gangneung, total rainfall in 2016 decreased by 50% compared with those in last 5 years average. Especially, there was almost no rain in tuber enlargement period (from mid-May to mid-June). On the other hand, the total rainfall in of Cheong-ju was is similar to those in last 5 years average. Inorganic components including K, Ca and Mg and plant growth factors such as plant length, stem length, leaf area index and plant biomass were investigated. Tuber yields in both areas were investigated at harvest. Growth period of plants was is longer in Cheong-ju than that in Gangneung. Contents of all inorganic components were higher in plants grown in Cheong-ju than in Gangneung. The results were attributed to higher production of plant biomass in Cheong-ju. Considering the results, severe drought stress conditions in Gangneung accelerated plant aging and resulted in low plant growth. Although total yield was greatly reduced under drought stress the rate of commercial yield was is not significantly different with non-drought conditions.