• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.734-744
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• 2011

A soil stabilization method is an effective and practical remediation alternative for arsenic (As) and heavy metal contaminated farmland soils nearby abandoned metal mine in Korea. This method is a technique whereby amendments are incorporated and mixed with a contaminated soil. Toxic metal bind to the amendments, which reduce their mobility in soil, so the successful stabilization of multi-element contaminated soil depends on the combination of critical elements in the soil and the type of amendments. The objective of this study is to investigate the treatment effects and applicability of limestone (LS) and steel refining slag (SRS) as the amendment for farmland soil contaminated with As and heavy metals, and a lab-column test was conducted for achieving this purpose. The result showed that soil treated with LS and SRS maintained pH buffer capacity and, as a result, the heavy metal leaching concentration was quite low below the water quality standard compared to untreated soil which leachate exceeding the water quality standard was observed, however, the arsenic concentration rather increased with increasing mixture ratio of SRS. This was believed to be related to phosphorus (P) contained in SRS, and dominancy in the competitive adsorption relation between As and P binding strongly to iron might be different according to soil characteristic. We suggested that LS is a effective amendment for reducing heavy metals in soil, and SRS should be used after investigating its applicability based on the adsorption selectivity of arsenic and phosphorus in selected soil.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.82-86
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• 2015

This study was carried out to develop the silkworm rearing technique in unused mulberry leaves after harvesting mulberry fruit. The growth of Gwasang No. 2 and Suhyang was very good compared to control cultivar Chungil in leaves size and new branch growth, but new branch and leaves of Daeshim was similar or small to control cultivar Chungil. The number of leaves of Gwasang No. 2 and Suhyang was lower than Chungil, but weight of leaves per tree was heavyer than Chungil. Mulberry leaf yield was Gwasang No. 2 521 kg/10a, Suhyang 189 kg/10a, Daeshim 73 kg/10a, Chungil 1,095 kg/10a. Content of mineral element of all three mulberry cultivars leaf for mulberry fruit production was higher than Chungil in N, P, K, Ca etc. Feeding quantity of silkworm of Gwasang No. 2 and Suhyang was much more than Chungil. Feeding quantity was highest at Suhyang in 96 kg/box. Growth duration of silkworm larvae was not different in all four mulberry culivars but weight of silkworms (5th instar 3rd day) was heavy at Gwasang No. 2 (2.07 g/head) and Suhyang (2.11 g/head) compared to control cultivar Chungil (1.92 g/head). Mortality of silkworms was 14.6% (Gwasang No. 2), 13.3% (Suhyang), 13.9% (Daesim), 12.6% (Chungil) and than higher at elder instar stage. The production amount of silkworm (5th instar 3rd day) was 35.4 kg/box (Gwasang No. 2), 36.6 kg/box (Suhyang), 35.0 kg/box (Daeshim), 33.6 kg/ box (Chungil). Amount of possible rearing silkworms was estimated 3.4box/10 a (Gwasang No. 2), 1.3box/10a (Suhyang), 0.5box/10a (Daeshim), 8.7box/10a (Chungil).

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.399-407
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• 2009

Laser induced breakdown spectroscopy(LIBS) is an simple analysis method for directly quantifying many kinds of soil micro-elements on site using a small size of laser without pre-treatment at any property of materials(solid, liquid and gas). The purpose of this study were to find an optimum condition of the LIBS measurement including wavelengths for quantifying soil elements, to relate spectral properties to the concentration of soil elements using LIBS as a simultaneous un-breakdown quantitative analysis technology, which can be applied for the safety assessment of agricultural products and precision agriculture, and to compare the results with a standardized chemical analysis method. Soil samples classified as fine-silty, mixed, thermic Typic Hapludalf(Memphis series) from grassland and uplands in Tennessee, USA were collected, crushed, and prepared for further analysis or LIBS measurement. The samples were measured using LIBS ranged from 200 to 600 nm(0.03 nm interval) with a Nd:YAG laser at 532 nm, with a beam energy of 25 mJ per pulse, a pulse width of 5 ns, and a repetition rate of 10 Hz. The optimum wavelength(${\lambda}nm$) of LIBS for estimating soil and plant elements were 308.2 nm for Al, 428.3 nm for Ca, 247.8 nm for T-C, 438.3 nm for Fe, 766.5 nm for K, 85.2 nm for Mg, 330.2 nm for Na, 213.6 nm for P, 180.7 nm for S, 288.2 nm for Si, and 351.9 nm for Ti, respectively. Coefficients of determination($r^2$) of calibration curve using standard reference soil samples for each element from LIBS measurement were ranged from 0.863 to 0.977. In comparison with ICP-AES(Inductively coupled plasma atomic emission spectroscopy) measurement, measurement error in terms of relative standard error were calculated. Silicon dioxide(SiO2) concentration estimated from two methods showed good agreement with -3.5% of relative standard error. The relative standard errors for the other elements were high. It implies that the prediction accuracy is low which might be caused by matrix effect such as particle size and constituent of soils. It is necessary to enhance the measurement and prediction accuracy of LIBS by improving pretreatment process, standard reference soil samples, and measurement method for a reliable quantification method.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.4
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• pp.195-209
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• 2021

According to the 2019-2020 social media usage survey conducted by the Seoul e-commerce center, 5 out of 10 consumers have experienced shopping through social media. The cost of traditional advertising media has been reduced and advertising spending on social media has risen by 74%, indicating that social media is becoming a more important marketing element. While the number of users of social media has increased and corporate marketing activities have increased accordingly, research has been conducted in various aspects of marketing such as user motivation for social media, satisfaction, and purchase intention. There was no subdivided study on the differences in the social media usage frequency of consumers in actual purchasing behavior. This study attempted to identify differences in consumer characteristics by cluster in the agrifood purchase situation by grouping them by type according to the frequency of use of social media for consumers who purchase agri-food online. Product involvement, product need, and online purchase channel Consumer characteristics such as demographic distribution, perceived risk, and eating and lifestyle in each cluster were checked for the three agrifood purchase situations including choice, and types for each cluster were presented. To this end, questionnaire data on the frequency of social media use and online agrifood purchase behavior were collected from 245 consumers, and the validity of the measurement variables was secured through factor analysis and reliability analysis. As a result of cluster analysis according to the frequency of social media use, it was divided into three clusters. The first cluster was a group that mainly used open social media, and the second cluster was a group that used both open and closed social media and online shopping malls; The third cluster was a group with low online media usage overall, and the characteristics of each cluster appeared. Through regression analysis, the effect on product involvement, product need, and purchase channel selection when purchasing agri-food online through each of the three clusters was confirmed through regression analysis. As a result of the regression analysis, the characteristic of cluster 1 in the situation of purchasing agri-food online is a male in his 30s living in a rural area who has no reluctance to purchase agri-food on social media or online shopping malls. The characteristics of cluster 2 are mainly consumers who are interested in purchasing health food, and the consumer characteristics are represented. In the case of cluster 3, when purchasing products online, they purchase after considering quality and price a lot, and the consumer characteristics are represented as people who are more confident in purchasing offline than online. Through this study, it is judged that by identifying the differences in consumer characteristics that appear in the agri-food purchase situation according to the frequency of social media use, it can be helpful in strategic judgments in marketing practice on social media customer targeting and customer segmentation.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.287-294
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• 2021

In order to expand facility agriculture and reduce greenhouse construction costs in reclaimed land, a greenhouse foundation method that satisfies economic feasibility and structural safety at the same time is required. As an alternative, the allowable bearing capacity and settlement were reviewed when the DCM(Deep cement mixing) method was applied among the soft ground reinforcement methods. To examine the applicability of the greenhouse foundation, the allowable bearing capacity and settlement were calculated by applying the theory of Terzaghi, Meyerhof, Hansen, and Schmertmann. In case of the diameter of 800mm and the width and length of the foundation of 4m, the allowable bearing capacity was 179kN/m² and the settlement was 7.25mm, which satisfies the required bearing capacity and settlement standards. The calculation results were verified through FEM(Finite element method) analysis using the Mohr-Coulomb material model. The allowable bearing capacity was 169kN/m² and the settlement was 2.52mm. The bearing capacity showed an error of 5.6% compared to calculated value, and the settlement showed and error of 65.4%. Through theoretical calculations and FEM analysis, it was confirmed that the allowable bearing capacity and settlement satisfies the design criteria as a greenhouse foundation when the width and length of the foundation were 4m. Based on the verified design values, it is expected to be able to present the foundation design criteria for greenhouses through empirical tests such as bearing capacity tests and long-term settlement monitoring.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.3
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• pp.157-167
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• 2021

Lead (Pb) is one of the key trace elements, exhibiting a peculiar partitioning behavior into silicate melts in contact with minerals. Partitioning behaviors of Pb between silicate mineral and melt have been known to depend on melt composition and thus, the atomic structures of corresponding silicate liquids. Despite the importance, detailed structural studies of Pb-bearing silicate melts are still lacking due to experimental difficulties. Here, we explored the effect of lead content on the atomic structures, particularly the evolution of silicate networks in Pb-bearing sodium metasilicate ([(PbO)_x(Na₂O)_1-x]·SiO₂) glasses as a model system for trace metal bearing natural silicate melts, using ²⁹Si solid-state nuclear magnetic resonance (NMR) spectroscopy. As the PbO content increases, the ²⁹Si peak widths increase, and the maximum peak positions shift from -76.2, -77.8, -80.3, -81.5, -84.6, to -87.7 ppm with increasing PbO contents of 0, 0.25, 0.5, 0.67, 0.86, and 1, respectively. The ²⁹Si MAS NMR spectra for the glasses were simulated with Gaussian functions for Qⁿ species (SiO₄ tetrahedra with n BOs) for providing quantitative resolution. The simulation results reveal the evolution of each Qⁿ species with varying PbO content. Na-endmember Na₂SiO₃ glass consists of predominant Q² species together with equal proportions of Q¹ and Q³. As Pb replaces Na, the fraction of Q² species tends to decrease, while those for Q¹ and Q³ species increase indicating an increase in disproportionation among Qⁿ species. Simulation results on the ²⁹Si NMR spectrum showed increases in structural disorder and chemical disorder as evidenced by an increase in disproportionation factor with an increase in average cation field strengths of the network modifying cations. Changes in the topological and configurational disorder of the model silicate melt by Pb imply an intrinsic origin of macroscopic properties such as element partitioning behavior.

• Korean Journal of Heritage: History & Science
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• v.54 no.4
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• pp.22-35
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• 2021

Recently, as the climate changes rapidly and the prevalence of airborne fine particulate matter increases, the pattern of pollutants in the atmospheric environment is also changing. Therefore, the importance of studying the stability of pigments used in colored cultural properties is emerging. Hoecheong is an inorganic blue glass pigment called smalt; it is made by using cobalt as a coloring element in potash glass, and was widely used in colored cultural assets, such as murals and paintings. In this study, we collected three other hoecheong pigments to analyze their properties. The percentage of Co and K contained are different according to the manufacturer, and the smalt-3 sample has a lower cobalt content (15.1 wt.%) and higher potassium content (29.6 wt.%). After this analysis, colored specimens were prepared. Prepared specimens were exposed to ultra-violet rays, CO₂/NO₂, and NaCl, which are known to have the greatest influence on the stability of pigments. We found that factors affecting the color stability were NO₂ gas, ultra-violet rays, and water-soluble salts (NaCl). Among them, NO₂ has the most severe impact on color change of the pigments. Results of the component analysis showed that the color change depends on the potassium and cobalt content of the hoecheong pigment. Among the specimens, smalt-3 showed the most vulnerability after exposure to NO₂ gas and water-soluble salts. Pigment film stability is affected by watersoluble salts, giving rise not only to color change, but also weakening the physical properties of the film. However, there was no significant change in composition and color after exposure to CO₂ gas. In conclusion, we found that hoecheong pigments underwent color change and increased instability of the coating film when exposed to any of the atmospheric environmental factors used in this study, except for CO₂.

• Korean Journal of Organic Agriculture
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• v.29 no.2
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• pp.223-240
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• 2021

This study was carried out to investigate the economic value of organic wheat production using gelatin·chitin microorganisms in Gwangsan-gu, Gwangju city. The soil condition of experiment field was clay loam Jisan series. The organically cultivated fields were sprayed gelatin and chitin degrading bacteria. The test was performed at conventionally cultivated field and organically cultivated field. Emergence of weed on organically cultivated field was significantly higher than conventionally cultivated field which sprayed herbicide before seeding. Weed emergence have a critical impact on grain yield. Occurrence of diseases and insect pests were higher than conventionally cultivated fields. In 2019, the amount of lodging in conventionally cultivated field were higher than conventionally cultivated field. In 2020, lodging and wet injury were occur in both field. Comparing yield element between organically and conventionally cultivated experimental area, grain yield in organically cultivated field was shown slightly higher amount than conventionally cultivated field. However in the actual yield of 2019, organically cultivated field shows 20% deceased yield because of overgrown weed. In 2020, weed emergence and yellow mosaic virus by wet injury cause 30% decease in the grain yield in organically cultivated field. Content of protein, carbohydrates, ash, water and fat in the grain were not different significance. In 2019, net incomes of conventionally cultivated wheat was 461,031 won/0.1 ha while organically cultivated wheat was 443,437 won/0.1 ha. In the rate of income, conventionally cultivated field was 83.0% as against organically cultivated field (73.3%). In 2020, net incomes of organically cultivated wheat was 437,812 won/0.1 ha while conventionally cultivated wheat was 418,281 won/0.1 ha. In the rate of income, conventionally cultivated field was 81.6% as against organically cultivated field (73.0%).

• Cross-Cultural Studies
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• v.50
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• pp.313-346
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• 2018

It is noted that generally speaking, the expressing of actualization or non-actualization of events is not the main role of possibility for the utilization of expressions. In spite of this fact, it is possible to see many examples in which possibility expressions represent actual events, and impossibility expressions represent a type of non-actualization in relation to events. This effect can be described as a semantic extension, by which the participant-internal possibility is extended to actualization due to participant-internal factors, and the participant-external possibility is extended to the actualization due to participant-external factors. When the related possibility expressions are used in this extended sense, they express the dynamic evaluative meaning of 'desirability' of the realized event, while it is determined that when the impossibility expressions are used in this extended sense, they are seen to express the evaluative meaning of 'regretfulness' about the non-actualization of the event. In Modern Japanese, it is noted that there are a few expressions of ability and possibility. They can be largely divided into four types of expressions, according to their origins or uses of expression, which are 'ability verbs', affixes '-れる/られる(-reru/rareru)', '-できる(-dekiru)', and '-得る(-eru)'. They can all express participant-internal possibility and participant-external non-deontic possibility. While 'ability verbs', affixes '-れる/られる' and '-できる' can express participant-external deontic possibility, '-得る' cannot. However, '-得る' is the only possible element to designate the event of a epistemic possibility. Also, the four types of expressions have the usage of conveying 'actualization/non-actualization,' as is the case of the Korean language. However in Japanese, in fact adjectives cannot be associated with 'ability verbs' or 'ability affixes.' Thus the expressions of 'regrets' should in that case depend on the use contexts, unlike the expression 'adj+-지 못하다' as noted in Korean. The ability and possibility in Modern Chinese are mainly expressed by means of the four auxiliary verbs '能($n{\acute{e}}ng$)', '会(huì)', '可以(kěyǐ)' and '可能 ($k{\check{e}}n{\acute{e}}ng$)'. '能' and '会' along with '可以' can all convey participant-internal possibility. In this way '能' and '可以' can express participant-external possibility. Only '会' and '可能' can express epistemic possibility. As for 'actualization,' among the four auxiliary verbs, only '能' can represent actualization. Also, among the negatives of the four auxiliary verbs, only '沒能' can represent non-actualization.

• Cross-Cultural Studies
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• v.50
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• pp.395-424
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• 2018

The purpose of this paper is to examine the current situation and background of the Russian consumer music market, where digital music sources are making great strides in the noted recent years. In addition, music storage technology, media and change are considered together in this report. Moreover, Russia is the 12th largest music market in the world. The Russian music industry is following the recent trend of the global music industry, where the digital music market is growing rapidly on many different levels. The explosive growth of the digital sound sources in Russia's music industry is attributed to the explosive increase in available consumer downloads, streaming sound source service, and the increase in the number of digital sound sources using mobile technologies due to the development of the Internet. In particular, the sales of the available and accessible streaming sound sources are expected to grow explosively by the year 2020, which is expected to account for more than 85% of total digital music sales. In other words, the spread of smartphones and the resulting changes in the lifestyle of the Russians have created these changes for the global consumer of music. In other words, the time has come for anyone to easily access music and listen to music without a separate audio or digital player. And the fact that the Russian government's strong policy on the eradication of illegal copying of music is becoming an effective deterrent, as is also the factor that led to the increase of the share of the digital sound source to increase sales in Russia. Today, the Russian music industry is leading this change through the age and process of simply adapting to the digital age. Music is the most important element of cultural assets, and it is the beneficial content, which drives the overall growth of the digital economy. In addition, if the following five improvements(First, strengthen the consciousness of the Russian people about copyright protection; Second, utilizing the Big Data Internet resources in the digital music industry; Third, to improve the monopoly situation of digital music distributors; Fourth, distribution of fair music revenues; and Fifth, revitalization of a re-investment in the current Russian music industry) are effective and productive, Russia's role and position in the world music market is likely to expand.