• Journal of Intelligence and Information Systems
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• v.23 no.3
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• pp.119-138
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• 2017

Recently, SNS has become an important channel for marketing as well as personal communication. However, cybercrime has also evolved with the development of information and communication technology, and illegal advertising is distributed to SNS in large quantity. As a result, personal information is lost and even monetary damages occur more frequently. In this study, we propose a method to analyze which sentences and documents, which have been sent to the SNS, are related to financial fraud. First of all, as a conceptual framework, we developed a matrix of conceptual characteristics of cybercriminality on SNS and emergency management. We also suggested emergency management process which consists of Pre-Cybercriminality (e.g. risk identification) and Post-Cybercriminality steps. Among those we focused on risk identification in this paper. The main process consists of data collection, preprocessing and analysis. First, we selected two words 'daechul(loan)' and 'sachae(private loan)' as seed words and collected data with this word from SNS such as twitter. The collected data are given to the two researchers to decide whether they are related to the cybercriminality, particularly financial fraud, or not. Then we selected some of them as keywords if the vocabularies are related to the nominals and symbols. With the selected keywords, we searched and collected data from web materials such as twitter, news, blog, and more than 820,000 articles collected. The collected articles were refined through preprocessing and made into learning data. The preprocessing process is divided into performing morphological analysis step, removing stop words step, and selecting valid part-of-speech step. In the morphological analysis step, a complex sentence is transformed into some morpheme units to enable mechanical analysis. In the removing stop words step, non-lexical elements such as numbers, punctuation marks, and double spaces are removed from the text. In the step of selecting valid part-of-speech, only two kinds of nouns and symbols are considered. Since nouns could refer to things, the intent of message is expressed better than the other part-of-speech. Moreover, the more illegal the text is, the more frequently symbols are used. The selected data is given 'legal' or 'illegal'. To make the selected data as learning data through the preprocessing process, it is necessary to classify whether each data is legitimate or not. The processed data is then converted into Corpus type and Document-Term Matrix. Finally, the two types of 'legal' and 'illegal' files were mixed and randomly divided into learning data set and test data set. In this study, we set the learning data as 70% and the test data as 30%. SVM was used as the discrimination algorithm. Since SVM requires gamma and cost values as the main parameters, we set gamma as 0.5 and cost as 10, based on the optimal value function. The cost is set higher than general cases. To show the feasibility of the idea proposed in this paper, we compared the proposed method with MLE (Maximum Likelihood Estimation), Term Frequency, and Collective Intelligence method. Overall accuracy and was used as the metric. As a result, the overall accuracy of the proposed method was 92.41% of illegal loan advertisement and 77.75% of illegal visit sales, which is apparently superior to that of the Term Frequency, MLE, etc. Hence, the result suggests that the proposed method is valid and usable practically. In this paper, we propose a framework for crisis management caused by abnormalities of unstructured data sources such as SNS. We hope this study will contribute to the academia by identifying what to consider when applying the SVM-like discrimination algorithm to text analysis. Moreover, the study will also contribute to the practitioners in the field of brand management and opinion mining.

• Economic and Environmental Geology
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• v.43 no.6
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• pp.589-601
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• 2010

Recently it has been frequently reported arsenic contamination of geologic origin in groundwater. The iron-impregnated ranular activated carbon (Fe-GAC) was developed for effective removal of arsenic from groundwater n the study. Fe-GACs were prepared by impregnating iron compounds into a supporting medium (GAC) with 0.05 M iron nitrate solution. The materials were used in arsenic adsorption isotherm tests to know the effect of iron impregnation time, batch kinetic tests to understand the influence of pH, and column tests to evaluate for the preliminary operation of water treatment system. The results showed that the minimum twelve hours of impregnation time were required for making the Fe-GAC with sufficient iron content for arsenic removal, confirmed by a high arsenic adsorption capacity evaluated in the isotherm tests. Most of the impregnated iron compounds were iron hydroxynitrate $Fe_4(OH)_{11}NO_3{\cdot}2H_2O$ but a mall quantity of hematite was also identified in X-ray diffraction(XRD) analysis. The batch isotherms of Fe-GAC for arsenic adsorption were well explained by Langmuir than Freundlich model and the iron contents of Fe-GAC have positive linear correlations on logarithmic plots with Freundlich distribution coefficients ($K_F$ and Langmuir maximum adsorption capacities ($Q_m$. The results of kinetic experiments suggested hat Fe-GAC had he excellent arsenic adsorption capacities regardless of all pH conditions except for pH 11 and could be used a promising adsorbents for groundwater arsenic removal considering the general groundwater pH range of 6-8. The pseudo-second order model, based on the assumption that the ate-limiting step might be chemisorption, provided the best correlation of the kinetic experimental data and explained the arsenic adsorption system f Fe-GAC. The column test was conducted to valuate the feasibility of Fe-GAC use and the operation parameters in arsenic groundwater treatment system. The parameters obtained from the column test were the retardation actor of 482.4 and the distribution coefficient of 581.1 L/mg which were similar values of 511.5-592.5 L/mg acquired from Freundlich batch isotherm model. The results of this study suggested that Fe-GAC could be used as promising adsorbent of arsenic removal in a small groundwater supply system with water treatment facility.

• Journal of Animal Environmental Science
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• v.16 no.1
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• pp.21-28
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• 2010

The odor problem in the livestock is increasing by 7% annually. Most importantly, the livestock odor problem in swinery accounts for the maximum ratio (54%). In this study, we reviewed the possibility of deodorizing swinery using an odor reduction device that can be used with the water washing system. First, the study confirmed that the solubility of odor gas, which was hydrogen sulfide, was very low regardless of the contact time with solvent, but the solubility of methyl mercaptan was found to increase along with the increase in time. The solubility of other odor gases, such as dimethyl sulfide, dimethyl disulfide and ammonia, was considerably high. Consequently, it is considered that if the odor reduction device for the water washing system deodorization is used in a swinery, the time during which the exhaust gas is in contact with usable water must be extended, or solvent quantity must be expanded. However, it is predicted that although hydrogen sulfide is easily generated in the anaerobic condition, it is difficult to expect high odor reduction efficiency because this gas has low solubility in water, especially in case it is used in the deodorization of the water washing system. The result of the solubility experiment using the bench-scale device practically manufactured represented the higher odor reduction ratio than expected. This result was possible because the removal efficiency of dust particles could be reached up to 93%. Therefore, it is judged that also the odor gas absorbed on dust particles could be removed by removal of dust. Consequently, it is expected that the higher order reduction ratio will be possible by structural improvement for increasing contact with water and odor gas.

• Korean Journal of Heritage: History & Science
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• v.54 no.4
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• pp.60-77
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• 2021

From 2007 to 2011, four Goryeo Dynasty vessels, namely the Taean treasure ship, Taean Mado Shipwreck No.1, No.2, No.3 were discovered in Taean area, Chungcheongnam-do province. From the shipwrecks, 175 pieces of mokkan (wooden tablet) were excavated. These mokkans are the only case of Goryeo Dynasty and represent the unique usage of mokkan as cargo tags, after the paper replaced the wooden tablets as writing materials. The Taean mokkans provide details, such as the year, recipient, port of origin, types of the cargo, quantity and unit, the name of the responsible person for shipment. Thus, they enable us to speculate about the characteristics of the cargo. Furthermore, through studying the writing style, form, material and manufacturing method, researchers can extract which form and characteristics were favored at that time. The Taean mokkans have no preset style for writing. Therefore, they can be written selectively and freely. And since the mokkan were attached to cargos, mokkans with furrows on upper side were favored, and efficiency and simplification of the manufacturing process were priorities in making mokkans. The Taean mokkans can be compared to those from the Shinan ship and the Quanzhou ship because those are of the same era and use. On the writing styles and information, Chinese mokkans are focused on the cargo owners, while The Taean mokkan includes more detailed information, such as the recipients. In forms, Chinese mokkans have maximum thickness of 1.0 centimeter and have pointed edges in lower parts, while mokkans from Taean do not have fixed thickness or edges. Furthermore, Chinese mokkans and Korean mokkans have different styles from manufacturing methods and material selections. These differences between Chinese and Goryeo mokkan are related to the differences between littoral-transport Goryeo ships and ocean-transport Chinese ships, such as shipping distances, types of cargo, shipping systems, packing methods, and transport operators. At the moment, because there are only small amount of data and materials of Chinese mokkan, comparative studies regarding Goryeo and Chinese mokkan can only be fragmentary. However, this article can be a base from which to expand the scope of Goryeo mokkan studies.

• Journal of the Korean earth science society
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• v.42 no.5
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• pp.524-535
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• 2021

Rapid climate change and oceanic warming have increased the variability of oceanic wave heights over the past several decades. In addition, the extreme wave heights, such as the upper 1% (or 5%) wave heights, have increased more than the heights of the normal waves. This is true for waves both in global oceans as well as in local seas. Satellite altimeters have consistently observed significant wave heights (SWHs) since 1991, and sufficient SWH data have been accumulated to investigate 100-year return period SWH values based on statistical approaches. Satellite altimeter data were used to estimate the extreme SWHs at the Ieodo Ocean Research Station (IORS) for the period from 2005 to 2016. Two representative extreme value analysis (EVA) methods, the Initial Distribution Method (IDM) and Peak over Threshold (PoT) analysis, were applied for SWH measurements from satellite altimeter data and compared with the in situ measurements observed at the IORS. The 100-year return period SWH values estimated by IDM and PoT analysis using IORS measurements were 8.17 and 14.11 m, respectively, and those using satellite altimeter data were 9.21 and 16.49 m, respectively. When compared with the maximum value, the IDM method tended to underestimate the extreme SWH. This result suggests that the extreme SWHs could be reasonably estimated by the PoT method better than by the IDM method. The superiority of the PoT method was supported by the results of the in situ measurements at the IORS, which is affected by typhoons with extreme SWH events. It was also confirmed that the stability of the extreme SWH estimated using the PoT method may decline with a decrease in the quantity of the altimeter data used. Furthermore, this study discusses potential limitations in estimating extreme SWHs using satellite altimeter data, and emphasizes the importance of SWH measurements from the IORS as reference data in the East China Sea to verify satellite altimeter data.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3B
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• pp.303-310
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• 2009

Natural zeolite is widely used as sorbents and bio-media materials because it is cheap as well as it has efficient porous structures and large cation exchange. In this study, the effect of metal cations $(Na^+,\;Ca^{2+},\;Mg^{2+},\;Al^{3+})$ adsorbed to natural zeolite on the microorganism attachment was investigated. Metal-modified zeolites (MMZ) were prepared with 0.01 M, 0.02 M and 0.1 M NaCl, $CaCl_2$, $MgCl_2$ and $AlCl_3$ solutions respectively, which concentrations were equivalent to 10%, 20% and 100% of cation exchange capacity (CEC) of natural zeolite. Pseudomonas putida was used as microorganism which was cultivated in Beef Extract Medium at $26^{\circ}C$. The microorganism attachment to MMZ was increased more than natural zeolite. The amount of bacterial adhesion to MMZ and natural zeolite were $Mg^{2+}>natural>Na^+>Al^{3+}>Ca^{2+}$ under 10% of CEC, $Mg^{2+}>Ca^{2+}>Al^{3+}>natural>Na^+$ under 20% of CEC and $Ca^{2+}>Mg^{2+}>natural>Al^{3+}>Na^+$ under 100% of CEC. Especially, Mg-modified zeolite (Mg-MZ) showed the highest amount of bacterial adhesion, which increased the microorganism attachment 60% higher than natural zeolite under 10% of CEC. However, the amount of bacterial adhesion was decreased as the concentration of metal cations modified to zeolite were increased, showing that the increased amounts were 60% under 10% of CEC, 50% under 20% of CEC and 10% under 100% of CEC in Mg-MZ. Additionally, the effect of $Mg^{2+}$ in solution on the bacterial adhesion was investigated in order to compare it with the effect of $Mg^{2+}$ adsorbed to zeolite. The maximum quantity of bacterial adhesion to Mg-MZ was not different from the amount of microorganism attachment to the natural zeolite when $Mg^{2+}$ solution was added.

• Magazine of the Korean Society of Agricultural Engineers
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• v.11 no.4
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• pp.1775-1782
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• 1969

The results of the study on the consumptine use of irrigated water in paddy fields during the growing season of rice plants are summarized as follows. 1. Transpiration and evaporation from water surface. 1) Amount of transpiration of rice plant increases gradually after transplantation and suddenly increases in the head swelling period and reaches the peak between the end of the head swelling poriod and early period of heading and flowering. (the sixth period for early maturing variety, the seventh period for medium or late maturing varieties), then it decreases gradually after that, for early, medium and late maturing varieties. 2) In the transpiration of rice plants there is hardly any difference among varieties up to the fifth period, but the early maturing variety is the most vigorous in the sixth period, and the late maturing variety is more vigorous than others continuously after the seventh period. 3) The amount of transpiration of the sixth period for early maturing variety of the seventh period for medium and late maturing variety in which transpiration is the most vigorous, is 15% or 16% of the total amount of transpiration through all periods. 4) Transpiration of rice plants must be determined by using transpiration intensity as the standard coefficient of computation of amount of transpiration, because it originates in the physiological action.(Table 7) 5) Transpiration ratio of rice plants is approximately 450 to 480 6) Equations which are able to compute amount of transpiration of each variety up th the heading-flowering peried, in which the amount of transpiration of rice plants is the maximum in this study are as follows: Early maturing variety ; Y=0.658+1.088X Medium maturing variety ; Y=0.780+1.050X Late maturing variety ; Y=0.646+1.091X Y=amount of transpiration ; X=number of period. 7) As we know from figure 1 and 2, correlation between the amount evaporation from water surface in paddy fields and amount of transpiration shows high negative. 8) It is possible to calculate the amount of evaporation from the water surface in the paddy field for varieties used in this study on the base of ratio of it to amount of evaporation by atmometer(Table 11) and Table 10. Also the amount of evaporation from the water surface in the paddy field is to be computed by the following equations until the period in which it is the minimum quantity the sixth period for early maturing variety and the seventh period for medium or late maturing varieties. Early maturing variety ; Y=4.67-0.58X Medium maturing variety ; Y=4.70-0.59X Late maturing variety ; Y=4.71-0.59X Y=amount of evaporation from water surface in the paddy field X=number of period. 9) Changes in the amount of evapo-transpiration of each growing period have the same tendency as transpiration, and the maximum quantity of early maturing variety is in the sixth period and medium or late maturing varieties are in the seventh period. 10) The amount of evapo-transpiration can be calculated on the base of the evapo-transpiration intensity (Table 14) and Tablet 12, for varieties used in this study. Also, it is possible to compute it according to the following equations with in the period of maximum quantity. Early maturing variety ; Y=5.36+0.503X Medium maturing variety ; Y=5.41+0.456X Late maturing variety ; Y=5.80+0.494X Y=amount of evapo-transpiration. X=number of period. 11) Ratios of the total amount of evapo-transpiration to the total amount of evaporation by atmometer through all growing periods, are 1.23 for early maturing variety, 1.25 for medium maturing variety, 1.27 for late maturing variety, respectively. 12) Only air temperature shows high correlation in relation between amount of evapo-transpiration and climatic conditions from the viewpoint of Korean climatic conditions through all growing periods of rice plants. 2. Amount of percolation 1) The amount of percolation for computation of planning water requirment ought to depend on water holding dates. 3. Available rainfall 1) The available rainfall and its coefficient of each period during the growing season of paddy fields are shown in Table 8. 2) The ratio (available coefficient) of available rainfall to the amount of rainfall during the growing season of paddy fields seems to be from 65% to 75% as the standard in Korea. 3) Available rainfall during the growing season of paddy fields in the common year is estimated to be about 550 millimeters. 4. Effects to be influenced upon percolation by transpiration of rice plants. 1) The stronger absorbtive action is, the more the amount of percolation decreases, because absorbtive action of rice plant roots influence upon percolation(Table 21, Table 22) 2) In case of planting of rice plants, there are several entirely different changes in the amount of percolation in the forenoon, at night and in the afternoon during the growing season, that is, is the morning and at night, the amount of percolation increases gradually after transplantation to the peak in the end of July or the early part of August (wast or soil temperature is the highest), and it decreases gradually after that, neverthless, in the afternoon, it decreases gradually after transplantation to be at the minimum in the middle of August, and it increases gradually after that. 3) In spite of the increasing amount of transpiration, the amount of daytime percolation decreases gadually after transplantation and appears to suddenly decrease about head swelling dates or heading-flowering period, but it begins to increase suddenly at the end of August again. 4) Changs of amount of percolation during all growing periods show some variable phenomena, that is, amount of percolation decreases after the end of July, and it increases in end August again, also it decreases after that once more. This phenomena may be influenced complexly from water or soil temperature(night time and forenoon) as absorbtive action of rice plant roots. 5) Correlation between the amount of daytime percolation and the amount of transpiration shows high negative, amount of night percolation is influenced by water or soil temperature, but there is little no influence by transpiration. It is estimated that the amount of a daily percolation is more influenced by of other causes than transpiration. 6) Correlation between the amount of night percoe, lation and water or soil temp tureshows high positive, but there is not any correlation between the amount of forenoon percolation or afternoon percolation and water of soil temperature. 7) There is high positive correlation which is r=+0.8382 between the amount of daily percolation of planting pot of rice plant and amount and amount of daily percolation of non-planting pot. 8) The total amount of percolation through all growin. periods of rice plants may be influenced more from specific permeability of soil, water of soil temperature, and otheres than transpiration of rice plants.

• Explosives and Blasting
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• v.9 no.1
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• pp.3-13
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• 1991

The cautious blasting works had been used with emulsion explosion electric M/S delay caps. Drill depth was from 3m to 6m with Crawler Drill ${\phi}70mm$ on the calcalious sand stone (soft -modelate -semi hard Rock). The total numbers of test blast were 88. Scale distance were induced 15.52-60.32. It was applied to propagation Law in blasting vibration as follows. Propagtion Law in Blasting Vibration $V=K(\frac{D}{W^b})^n$ were V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W : Maximum charge per delay-period of eight milliseconds or more (kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents where the quantity $\frac{D}{W^b}$ is known as the scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagorized in three groups. Cubic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge Per delay Plots of peak particle velocity versus distoance were made on log-log coordinates. The data are grouped by test and P.P.V. The linear grouping of the data permits their representation by an equation of the form ; $V=K(\frac{D}{W^{\frac{1}{3}})^{-n}$ The value of K(41 or 124) and n(1.41 or 1.66) were determined for each set of data by the method of least squores. Statistical tests showed that a common slope, n, could be used for all data of a given components. Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom over loom distance because the frequency is verified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30m ------- under l00m ${\cdots\cdots\cdots}{\;}41(D/sqrt[2]{W})^{-1.41}{\;}{\cdots\cdots\cdots\cdots\cdots}{\;}A$ Over 100m ${\cdots\cdots\cdots\cdots\cdots}{\;}121(D/sqrt[3]{W})^{-1.66}{\;}{\cdots\cdots\cdots\cdots\cdots}{\;}B$ where ; V is peak particle velocity In cm / sec D is distance in m and W, maximLlm charge weight per day in kg K value on the above equation has to be more specified for further understaring about the effect of explosives, Rock strength. And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.147-155
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• 1977

In this experiment, we expected yield increase depending on the control of ineffective tiller, heightening of effective tillering ratio and continuous supply of nitrogen until later growth stage of rice plant by deep layer split application. Treats were applied at Tongil and Jinheung variety, clayey loam and sandy loam soil, and drained and non-drained condition. Nitrogenous fertilizer application wab adopted as liquefied(50%) and lumped (50% and 80%) fertilizer at 12cm depth of soil before 35 days of rice heading time against the standard soil surface application. The results are summarized as follaw. 1. a. Jinheung showed great variant width of tiller numbers per rice plant growth stage, and low effective tillering ratio at soil surface dressing. But in the case of deep layer split application, the number of tiller increased normally, and effective tillering ratio was high. b. At Tonsil, the width of increase and decrease range of effective tiller number between soil surface dressing and deep layer split application was not so high as Jinheung. Deep layer split application of 80% lumped fertilizer showed maximum effective tillering ratio ($83%{\sim}93%$). C. In the case of Jinheung, it was supposed that deep layer split application of 80% lumped fertilizer was excessive nitrogen quantity. d. Effective tillering ratio was higher than Tonsil at Jinheung. 2. The number of grains per hill was increased by the deep layer split application, but the ripening ratio was decreased inversely with the increase of total grain number. 3. Length of top leaves was elongated at Jinheung by deep layer split application. It showed significant correlation between top leaves length and grain yield. 4. Deep layer split application inclosed N content of harvested straw. Yield and N content of straw showed possitive correlation. 5. The ratio of unhulled grain yield per straw weight was increased by deep layer splication. This ratio was higher at Jinheung than Tonsil. 6. Grain yield was appeared in order of 80% lumped fertilizer>50% lumped fertilizer>50% liquefied fertilizer>surface dressing by the deep layer split application. The yield increasing factors were the increasing of effective tillering ratio, number of panicles per hill and number of ripening grains per hill. 7. Grain yield was increased at Tongil in sandy loam soil and at Jinheung in clayey loam soil by deep layer split application. 8. The grain yield was increased at drained conditions of clayey loam soil and non-drained conditions of sandy loam soil. But in the case of 80% lumped fertilizer of deep layer split application at the sandy loam soil, the yield was not increased at non-drained conditions. 9. The effect of yield increase by deep layer split application comparing with the surface dressing was higher at Tonsil than ginheung, in spite of low ripening ratio of Tonsil caused by low temperature at heading and harvesting time.