• Korean Journal of Remote Sensing
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• v.36 no.3
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• pp.487-501
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• 2020

As a viable option for retrieval of LST (Land Surface Temperature), this paper presents a DNN (Deep Neural Network) based approach using 148 Landsat 8 images for South Korea. Because the brightness temperature and emissivity for the band 10 (approx. 11-㎛ wavelength) of Landsat 8 are derived by combining physics-based equations and empirical coefficients, they include uncertainties according to regional conditions such as meteorology, climate, topography, and vegetation. To overcome this, we used several land surface variables such as NDVI (Normalized Difference Vegetation Index), land cover types, topographic factors (elevation, slope, aspect, and ruggedness) as well as the T₀ calculated from the brightness temperature and emissivity. We optimized four seasonal DNN models using the input variables and in-situ observations from ASOS (Automated Synoptic Observing System) to retrieve the LST, which is an advanced approach when compared with the existing method of the bias correction using a linear equation. The validation statistics from the 1,728 matchups during 2013-2019 showed a good performance of the CC=0.910~0.917 and RMSE=3.245~3.365℃, especially for spring and fall. Also, our DNN models produced a stable LST for all types of land cover. A future work using big data from Landsat 5/7/8 with additional land surface variables will be necessary for a more reliable retrieval of LST for high-resolution satellite images.

• Journal of Korean Society of Disaster and Security
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• v.7 no.2
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• pp.25-34
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• 2014

This study researches on global technology trend in each of composing technology, such as grouting material, grouting equipment, and construction management technology, which grouting technology has been founded upon to improve relatively inadequate domestic grouting technology and to establish the global standard for overseas expansion in the future. As far as grouting material is concerned, while High-Penetration and High-Strength micro cement ($1.5{\mu}m$) has been developed in 2000's in Japan, JinChun Kim et al. (2014) has been developing hybrid type micro cement grouting material and examining specifications of different kinds of projects and countries to analyze the trend of grouting equipment development. The specification contains detailed requisite specification for materials, mixers, pumps, agitators, and packers and it has to satisfy the standard of different countries to win global contracts. Grouting management technology can be divided into four different generations and Scandinavian countries, such as Sweden, Norway, and Finland, Japan, and South Korea are recently doing vigorous researches on the Fourth generation which merges grouting technology with ICT.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.136-142
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• 2018

Additive manufacturing process technology, known as the 3D printing process, is expanding its utilization from simple model realization to commercialized part production based on continuous material development. Recently, research and development have been actively carried out to fabricate lightweight and high-strength parts using polymers, such as polyamide (polyamide), which is a high-strength engineering plastic material. In this study, the Izod impact characteristics were analyzed for polyamide 12 (PA12) materials. For the specimen production, selective laser sintering process technology, which has excellent mechanical properties of finished products, was applied. In addition, PA12 and glass bead reinforced PA12 materials were produced. The specimens were classified according to the production direction on the production platform, and each specimen was subjected to an Izod test at test temperatures of $-25^{\circ}C$, $25^{\circ}C$, and $60^{\circ}C$. As a result, the impact strength of PA12 and glass bead-reinforced PA12 of vertical direction specimens were 48.8% and 16.3% lower than those of the parallel specimens at a $25^{\circ}C$ test temperature and the impact strength of parallel specimens was improved by 46.5% and 20.4% at a test temperature of $60^{\circ}C$ compared to that at $-25^{\circ}C$.

• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.209-218
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• 2010

There experiment were carried out to analyze for pesticide residues in 4 kinds of dried fruits collected in northern area of Seoul in 2007~2009. Total of 213 samples were analyzed. According to the results, 20 kinds of residual pesticides were detected. Residual pesticides were detected in 66 samples (31.0%) and 8 samples (3.8%) exceeded maximum residue limits (MRL). Cypermethrin, fenvalerate, endosulfan, chlorpyrifos, bifenthrin were detected frequently. The Pesticide types which were detected in dried furits were revealed in order of pyrethroid > organophosphate > organochloride > dicarboximide. Detection rates of dried fruits were dried chinese matrimony vein (53.0%), dried jujube (34.9%), dried rubi fructus (7.6%) and dried maximowiczia chinensis (4.6%). Based on these results, we investigated the risk assessment from amount of residual pesticide in dried jujube. Range of %ADI were 0.0001~0.0081%, but the value has not effected on human health.

• Water for future
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• v.29 no.6
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• pp.179-188
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• 1996

The chronical sequences of daily precipitation are of great practical importance in the planning and operational processes of water resources system. A sequence of days with alternate dry day and wet day can be generated by two state Markov chain model that establish the subsequent daily state as wet or dry by previously calculated vconditional probabilities depending on the state of previous day. In this study, a synthetic generation model for obtaining the daily precipitation series is presented by classifying the precipitation amount in wet days into multi-states. To apply multi-state Markov chain model, the daily precipitation amounts for wet day are rearranged by grouping into thirty states with intervals for each state. Conditional probabilities as transition probability matrix are estimated from the computational scheme for stepping from the precipitation on one day to that on the following day. Statistical comparisons were made between the historical and synthesized chracteristics of daily precipitation series. From the results, it is shown that the proposed method is available to generate and simulate the daily precipitation series with fair accuracy and conserve the general statistical properties of historical precipitation series.

• Korean journal of communication and information
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• v.30
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• pp.35-87
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• 2005

This research explores the empirical confirmation of the Internet development including from the period of innovation to the time of social-cultural use in today. The research focused on how tradition news media rover about the Internet developed from early to today, and understanding the media characteristics on the each stages from news frame. The research Is designed to conduit content analysis from 1989 to 2004, then this research is divided four(4) stages of the Internet development: innovation, diffusion, commercial usage, social-cultural usage. The results shows that there are significant different coverage by the stages. First of all, the news coverage pattern shift from technology focused on early stages to social usage focused on the later stages. This research confirms that the ratio of the seriation(technology) coverage defined when social usage is increased, on the other hand skeumorphs(social usage and content) coverage is increased in the commercial and social usage stages. This coverage pattern among news media does not such a big different and there is no competitive coverage. Moreover, the news coverage shifted from thematic coverage on early stages to episodic coverage while the number of usage increasing. In addition, the tone of coverage has not been changed significantly.

• Journal of Korean Society of Forest Science
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• v.82 no.2
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• pp.176-187
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• 1993

Based on the analysis of ecomorphological characters for 84 tree and shrub species, climax indices were estimated so as to interpret the position of the successional sere for the species in the natural deciduous forest. Nineteen ecomorphological characters, considered to be associated with successional gradient in the forest, were selected for the study. One of 2 to 4 steps per character for each species was given on a standardized scale of increasing climaxness, and the index was computed by percent of the sum of the scoring values for total score. Calculated mean value of 54.2 for all indices. Carpinus laxiflora had the highest index value of 83.3, and Populus davidiana recorded the lowest of 18.8. The most climax group, greater than 70 of the index, contained only 9 species, intermediate group, between 40 to 70 of the index, had 58 species, and the most pioneer group, less than 40 of the index comprised 17 species. The result has noticed that the large number of species would take advantage of most diverse resource and niche in the intermediate stage of the sere in the forest. The three components, i.e., light absorption, reproduction, and wood quality were used as axes for a 3-dimensional projection of the relative position for 44 species by principal component analysis. Along the similar ecomorphological characters, four recognized species group were classified by cluster analysis. The distribution pattern of plant families on the index gradient showed that the Betulaceae and Aceraceae had the widest seral amplitude, and the Salicaceae was a family typified as pioneer. There were no families specializing entirely with climax niche.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.367-373
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• 2010

The study was established to compare fruit qualities and antioxidant compounds in 'Niitaka' pear (Pyrus pyriforia) trees grown in the organic and conventional farming systems. Fruits in the organic system appeared to have dark red color on the fruit surface. Fruit weight, soluble solids, acidity, firmness, and stone cells were not different between the farming systems. Organic fruits had a greater potassium concentration than the conventional fruits, but phosphorous, calcium, and magnesium concentrations in fruits were not different between the treatments. Peel, flesh, and juice parts in the organic fruits had greater phenolic compounds compared to the conventional fruits. Peel parts had much greater antioxidant compounds than the flesh parts, regardless of the treated-fruits. All fruits grown in the conventional and organic systems had a similar DPPH ($\alpha$, $\alpha$-diphenyl-$\beta$-picryl-hydrazyl) radical-scavenging activity in the peel, but flesh parts in organic fruits had a greater DPPH than the conventional fruits. Phenol and flavonoid compounds in the peel and flesh were positively related to the DPPH radical-scavenging activity. There were no significant differences for the nitrite scavenging activity in the peel and flesh parts between the treatments.

• KDI Journal of Economic Policy
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• v.32 no.3
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• pp.101-137
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• 2010

This paper defines markets relating to each paid broadcasting service by applying the test method of critical sales loss to the results of survey to the paid service subscribers. The result confirms the existence of a meaningful competitive relationship--in terms of the Competition Law--among all paid broadcasting services included in this study, or at least analog cable broadcasting, digital cable broadcasting, and real time IPTV(Internet Protocol TV) service. This indicates that current regulations which are being applied to cable TV, satellite broadcasting, and IPTV are actually discriminatory. Based on these analysis results, this paper suggests that the main attention for the improvement of regulations should be focused on regulations which are differently applied to different paid service providers. In particular, Article 20 in the Internet Multimedia Broadcasting Law is interpreted as defining the real-time IPTV as an independent market, thereby having leeway to harm fair competition among different paid service providers. Therefore, that article needs to change to give the right of equal access to contents to all the competing paid service providers. Furthermore, to put teeth in the contents equal access rule, most popular pay channels need to be designated as target contents of the rule. As for the market-share limitation regulations, the paper suggests that an upper limit on the market share should be set based on the total number of subscribers of all the competing paid services and the same limit applied to all the competing paid service providers.

• The Korean Journal of Pesticide Science
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• v.18 no.3
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• pp.161-167
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• 2014

This study was conducted to investigate the resistance of Botrytis cinerea to azoxystrobin, which belongs to strobilurin fungicides. The sensitivity of B. cinerea isolates, which were collected from infected pepper, strawberry, cucumber and tomato by a single spore isolation, to the fungicide was tested through a agar dilution method on PDA amended with fungicides and $100{\mu}g\;mL^{-1}$ of salicylhydroxamic acid (SHAM). All isolates of B. cinerea tested in this study were classified as a sensitive and a resistant group by $1.0{\mu}g\;mL^{-1}$ of $EC_{50}$ value to azoxystrobin. While the sensitive isolates accounted for 46.5% of B. cinerea population, the resistant ones did for 53.5%. According to the regions isolating B. cinerea, the highest isolation frequency was showed as 81.1% in Chungnam among the all. Among 4 host plants as pepper, strawberry, cucumber and tomato, the highest isolation frequency was obtained in strawberry, while the lowest was done in pepper. The isolate resistant to azoxystrobin showed the cross resistance to other fungicides included into strobilurins as kresoxim-methyl and trifloxystrobin. In spite of an excellent efficacy of strobilurins, it should be taken care to use them in the field, because of the high risk in the fields.