• Journal of Environmental Science International
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• v.23 no.12
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• pp.2045-2056
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• 2014

In this study, pressure drop was measured in the pulse jet bag filter without venturi on which 16 numbers of filter bags (Ø$140{\times}850{\ell}$) are installed according to operation condition(filtration velocity, inlet dust concentration, pulse pressure, and pulse interval) using coke dust from steel mill. The obtained 180 pressure drop test data were used to predict pressure drop with multiple regression model so that pressure drop data can be used for effective operation condition and as basic data for economical design. The prediction results showed that when filtration velocity was increased by 1%, pressure drop was increased by 2.2% which indicated that filtration velocity among operation condition was attributed on the pressure drop the most. Pressure was dropped by 1.53% when pulse pressure was increased by 1% which also confirmed that pulse pressure was the major factor affecting on the pressure drop next to filtration velocity. Meanwhile, pressure drops were found increased by 0.3% and 0.37%, respectively when inlet dust concentration and pulse interval were increased by 1% implying that the effects of inlet dust concentration and pulse interval were less as compared with those changes of filtration velocity and pulse pressure. Therefore, the larger effect on the pressure drop the pulse jet bag filter was found in the order of filtration velocity($V_f$), pulse pressure($P_p$), inlet dust concentration($C_i$), pulse interval($P_i$). Also, the prediction result of filtration velocity, inlet dust concentration, pulse pressure, and pulse interval which showed the largest effect on the pressure drop indicated that stable operation can be executed with filtration velocity less than 1.5 m/min and inlet dust concentration less than $4g/m^3$. However, it was regarded that pulse pressure and pulse interval need to be adjusted when inlet dust concentration is higher than $4g/m^3$. When filtration velocity and pulse pressure were examined, operation was possible regardless of changes in pulse pressure if filtration velocity was at 1.5 m/min. If filtration velocity was increased to 2 m/min. operation would be possible only when pulse pressure was set at higher than $5.8kgf/cm^2$. Also, the prediction result of pressure drop with filtration velocity and pulse interval showed that operation with pulse interval less than 50 sec. should be carried out under filtration velocity at 1.5 m/min. While, pulse interval should be set at lower than 11 sec. if filtration velocity was set at 2 m/min. Under the conditions of filtration velocity lower than 1 m/min and high pulse pressure higher than $7kgf/cm^2$, though pressure drop would be less, in this case, economic feasibility would be low due to increased in installation and operation cost since scale of dust collection equipment becomes larger and life of filtration bag becomes shortened due to high pulse pressure.

• Korean Journal of Heritage: History & Science
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• v.53 no.3
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• pp.142-163
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• 2020

In the early Joseon dynasty, the meritorious vassals' portrait of Jeokgae (1467, 1476), Jeongguk (1506)·Jeongnan (1507), and Wisa (1545) were defined as the 2^nd period of the official uniform, in which the acheongsaek HeukDanryung appeared and settled. A total of seven portraits were analyzed, including three portraits of Jeokgae (1467, portrait production 1476) Son-so, Oh Jachi, and Jang Malson, and four portraits of Jeongguk (1506)·Jeongnan (1507) Yoo Sunjung, Hong Gyeongju, Lee Woo, and Yoo Hong. In the portrait of the Jeokgae wearing a Yebok HeukDanryung, in the case of the Samo, the height of the Samo, which had been raised at the beginning of King Seongjong, was lowered again, and the parietal part was rounded. The pattern was not expressed on the wide oval side wings of the Samo. In addition, the pattern was not expressed on the acheongsaek Danryung, Dapho, and Cheolrik. The colors of Dapho and Cheolrik were unified in green and red, respectively. The Mu of Danryung and Dapho was expressed as 'in and out wrinkled Mu', and the shoes were expressed in Baekhwa. Another feature is that the Jeokgae's portrait is expressed not as the Pumgye at the time of appointment, but as the Pumgye of the portrait production time. In the portrait of the Jeongguk·Jeongnan wearing a Sibok HeukDanryung, the height of the Samo lowered from the Jeokgae was maintained, while the parietal part was slightly narrowed and bent forward. The side wings of the Samo were expressed as an oval with a uniform width, and still the pattern was not expressed on the side wings. The pattern was not expressed in the costume of the Danghagwan's portrait, but the cloud pattern began to be expressed in the costume of the Dangsanggwan's portrait. And the Danryung was expressed as single Danryung without lining. In the portrait of Dangsang, the red Dapho and green Cheolrik were expressed, and in the portrait of Dangha, the green Dapho and blue Cheolrik were expressed. Therefore, it was found that the color of the undergarment was distinguished according to the Dangsang and Dangha. In Danryung and Dapho, the 'in and out wrinkled Mu' were maintained. The shoes were expressed in Heukhwa, and the rank badge and rank belt reflect the Pumgye at the time of the appointment. On the other hand, the portrait of Wisa could not be confirmed, but through the recording painting of the reign of King Meongjong, it was found that it was similar to the Danryung system of the reign of King Jungjong. Through the 2^nd period of the meritorious vassal's portrait of Jeokgae, it was confirmed that the HeukDanryung outfit began to be used as the official uniform of the meritorious vassal's portrait, and that the Pumgye of the portrait production time was reflected in the portrait. After the meritorious vassal's portrait of Jeongguk, the pattern began to be expressed in the costumes, and in particular, it was possible to distinguish Dasang and Dangha by the presence or absence of the HeukDanryung's pattern. In addition, it was confirmed that the expressed aspect of the official uniform was consistent with the practices and regulations at the time.

• Journal of Energy Engineering
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• v.29 no.1
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• pp.85-99
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• 2020

This article analyzes the influence of sectoral system of innovation(i.e. technological regime, market demand, networks, and institution) on innovative performances(i.e. product-, process-, organizational-, marketing-, and environmental- innovation) in Korean environmental industry, conducting a multiple regression analysis based on survey data from 201 Korean environmental companies. As the results, product innovation is positively influenced by internal technology accumulation and market demand response, while not affected by external knowledge utilization, market competition, networks among market and non-market agents, government support and regulation. Process innovation is positively influenced by internal technology accumulation, networks among non-market agents and regulation, but not by external knowledge utilization, market demand response, market competition, networks among market agents, and government support. While organizational innovation is positively influenced by internal technology accumulation, external knowledge utilization and regulation, it is not affected by market demand response, market competition, networks among market and non-market agents, and government support. While marketing innovation is positively influenced by internal technology accumulation, networks among non-market agents, and government support, it is not affected by external knowledge utilization, market demand response, market competition, networks among market agents, and regulation. Environmental innovation is positively influenced by external knowledge utilization and regulation, but negatively influenced by market competition. It is not affected by internal technology accumulation, market demand response, networks among market and non-market agents, and government support. Such results suggests the following policy implications. First, it is necessary to expand the sphere of relating markets through the application of convergence technology, new regulations, and overseas markets. Second, reinforcing ecosystems among environmental market agents through demand-linked joint R&D should be revitalized. Third, it is needed to strengthen more supporting policies rather than regulation. This article has the limitation of using the survey data. And further researches on the environmental sectoral system of innovation structure itself will be tried.

• Food Science and Preservation
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• v.22 no.3
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• pp.437-442
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• 2015

In a continuing screening of selected medicinal plants native to South Korea, the antioxidant and pancreatic lipase inhibitory activities of an aqueous methanolic extract from the heartwood of Aquilaria agallocha were investigated. Eighty percent of the methanolic extract of A. agallocha was further divided into $CH_2Cl_2$, EtOAc and n-BuOH in order to yield four solvent-soluble portions, namely $CH_2Cl_2$-soluble, EtOAc-soluble, n-BuOH-soluble and $H_2O$ residue. The antioxidant properties were evaluated by employing radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) ($ABTS^+$) radicals, while the anti-obesity efficacy of A. agallocha extracts and solvent-soluble portions were tested by porcine pancreatic lipase assay. All tested samples showed dose-dependent radical scavenging and pancreatic lipase inhibitory activities. Among the tested extracts and solvent-soluble portions, the $CH_2Cl_2$-soluble portion showed much higher radical scavenging activity and pancreatic lipase inhibitory properties when compared with other solvent-soluble portions. This result suggested that there was a significant relationship between the total phenolic content and biological efficacies, and A. agallocha extract might be considered as a new potential source of natural antioxidants and as a pancreatic lipase inhibitory source. A more systematic investigation of this biomass will be performed for further investigation of activity against antioxidative and anti-obesity effects.

• Management & Information Systems Review
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• v.36 no.2
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• pp.157-185
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• 2017

This study was carried out with the attention that the concept of entrepreneurial orientation has been applied at various levels of CEO, employee, management, and organization as a whole. The differences between these concepts were examined by discriminant validity and convergence validity, and the causal relationship between these concepts and performance was analyzed. A total of 96 questionnaires were collected and analyzed. The results show that CEO's entrepreneurial orientation, employee's entrepreneurial orientation, manager's entrepreneurial orientation and organizational entrepreneurial orientation have convergent validity and discriminant validity, and that these variables have different effects on the firm 's innovation performance and financial performance. In the analysis of the mediating effect, when the variables of all levels were put into a single variable, the innovation performance mediates between the entrepreneurial orientation and the financial performance in all variables. However, when all variables are applied simultaneously, innovation performance has mediating effect only on the relationship between organizational entrepreneurship orientation and financial performance. This shows that there is a conceptual difference according to applied level. As a result of the analysis of the causal relationship by the application level of entrepreneurial orientation, it is found that causality is formed among the entrepreneurial orientation variables. In particular, CEO's entrepreneurial orientation influences employee's entrepreneurial orientation, manager's entrepreneurial orientation, and organization's entrepreneurial orientation, and again, employee's entrepreneurial orientation and managerial entrepreneurial orientation form a causal relationship that influences organization's entrepreneurial orientation. In the relationship between innovation performance and financial performance, CEO's entrepreneurial orientation, organization's entrepreneurial orientation, and manager's entrepreneurial orientation are influencing innovation performance, and the only variables influencing financial performance are organization's entrepreneurial orientation. In conclusion, the limitations of the study and its future direction are presented.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.6-13
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• 2018

Utilizing the heat of cooling water discharge of coal-fired power plant, pipeline investment costs for businesses that supply heat to agricultural facilities near power plants increase in proportion to installation distance. On one hand, the distance from the power plant is a factor that brings difficulties to secure economic efficiency. On the other, if the installation distance is short, there is a problem of securing the heating demands, facility houses, which causes economical efficiency to suffer. In this study, the economic efficiency of 1km length of standard heat pipeline was evaluated. The sensitivity of the heat pipe to the new length variation was analyzed at the level of government subsidy, amount of heating demand and the incremental rate of pipeline with additional government subsidy. As a result of the analysis, it was estimated that NPV 131 million won and IRR 15.73%. The sensitivity analysis showed that NPV was negative when the length of heat pipe facility exceeded 2.6 km. If the government supports 50% of the initial investment, the efficiency is secured within the estimated length of 5.3 km, and if it supports 80%, the length increases within 11.4 km. If the heat demand is reduced to less than 62% at the new length of the standard heat pipe, it is expected economic efficiency is not obtained. If the ratio of government subsidies to initial investment increases, the elasticity of the new bloc will increase, and the fixed investment, which is the cost of capital investment for one unit of heating demand, will decrease. This would result in a reduction in the cost of production per unit, and it would be possible to supply heat at a cheaper price level to the facility farming. Government subsidies will result in the increased economic availability of hot plumbing facilities and additional efficiencies due to increased demand. The greater government subsidies to initial investment, the less farms cost due to the decrease in the price per unit. The results of the study are significant in terms of the economic evaluation of the effectiveness of the government subsidy for the thermal power plant heat utilization project. The implication can be applied to any related pilot to come.

• Korean Journal of Heritage: History & Science
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• v.53 no.2
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• pp.180-203
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• 2020

In this study, the period before the Gwanbok of meritorious vassals' portraits was expressed in the acheongsaek-Heuk-Danryung was defined as the first period, and the costumes worn in portraits of meritorious vassals from Gaeguk (1392) in the early Joseon Dynasty to Jwali (1471) during the era of King Seongjong were reviewed. The portraits(1476) of Jeokgae meritorious vassals (1467) depicted as the Gwanbok of acheongsaek Heuk-Danryung were excluded. Among the copies that are currently considered to be portraits of meritorious vassals belonging to the first period, the portraits of Lee-je, Lee Cheon-woo, Ma Cheon-mok, Shin Suk-ju, Seol Gye-jo, and Lee Sung-won were selected, and the formative characteristics of Gwanbok components were examined. The Samo of Sam-Gongsin in the early Joseon Dynasty had a low height, a rounded end, and the side wings were narrow and short. However, since King Danjong, Jeongnan·Jwali meritorious vassals retained a higher form, and the side wings were twice as long. It was also confirmed that the pattern was not expressed in the side wings. The Danryung was expressed in light-colored Danryung without specific colors at the beginning of the country. After King Sejong, the Heuk-Danryung system for Yebok began, but it was not reflected in the Gwanbok of meritorious vassals' portraits, and was expressed as damhongsaek-Danryung after King Danjong. The pattern was not expressed on the exterior of the Danryung, and inner-wrinkled Mu was expressed on the side line. The Dapho and Cheolrik, the undergarments of the Danryung, were also confirmed as being blue (the Dapho) and green (the Cheolrik) after the Jeongnan meritorious vassals. The early Sam-Gongsin's Pumgye was expressed by rank belt, but as the system of rank badge was established after King Danjong, it began to express the Pumgye by rank badge and rank belt. Among the portraits of meritorious vassals, the rank badge was expressed only in the portrait of Sin Suk-ju, a Jeongnan meritorious vassal. As Hwaja worn on the Danryung, Heuk-hwa were confirmed in the Sam-Gongsin portraits of the early Joseon Dynasty. However, in the portraits of Jeongnan and Jwali meritorious vassals after King Danjong, the Baek-hwa was confirmed. In addition, in the seam parts of the Heuk-hwa and Baek-hwa identified in some portraits of meritorious vassals, Hwi decorated with yeongeumsa were identified, and it was found that the Hwaja decorated with Hwi were the Hyeopgeum-hwa worn by the 3rd rank and above.

• Journal of Nutrition and Health
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• v.51 no.6
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• pp.580-589
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• 2018

Purpose: The purpose of this study was to evaluate the food insecurity status and dietary behavior and examine the association between the food insecurity status and consumption of processed beverage for secondary school students in Vientiane, capital city of Lao PDR. Methods: The study subjects are 714 students (boys = 307 and girls = 407) in four secondary schools (Chao_Anouvong, Phiavat, Saysetha, and Chansavang) of Vientiane, Lao PDR. Data on study subject's demographic characteristics, dietary behavior, food insecurity, and Mini Dietary Assessment (MDA) index were collected. A "Self-Administered Food Security Survey Module for Children Aged 12 Years and Older" developed by the United States Department of Agriculture (USDA) was used for the food insecurity assessment. Results: As a result, 72.7% of the subjects were in a state of food insecurity, and food security was associated with higher socioeconomic status (higher life satisfaction, higher parent's education attainment, higher item ownership, fewer number of siblings, and having more lunches at the school restaurant than at home). Compared to the food insecurity group, the frequency of breakfast, self-rated diet, and the total score of MDA index were higher in the food security group. On the other hand, multiple logistic regression analysis showed that 'food security' was also associated with a higher consumption of processed beverages (OR 1.544; 95% CI 1.078-2.213; p = 0.018). Conclusion: Improving the quality of the diet is essential for adolescents in both the food insecurity and food security groups in Lao PDR. Therefore, it is necessary to provide well organized nutrition education and establish adequate nutrition policy for adolescents in Lao PDR.

• Research in Plant Disease
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• v.26 no.4
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• pp.272-278
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• 2020

The severe lettuce damage caused by Paratylenchus projectus was first reported in 2019 in Korea. To find high-value rotation crops for the control of P. projectus, nine vegetables, Brassica juncea (leaf mustard), B. rapa subsp. nipposinica (kyona), B. oleracea var. italica (broccoli), B. rapa subsp. chinensis (bok choy), B. oleracea var. viridis (kale), B. oleracea var. gongylodes (kohlrabi), Cichorium endivia (endive), C. intybus (chicory), Ipomoea aquatica (morning glory) were planted in d-10-cm clay pots in greenhouse. The growth of vegetables was compared between inoculated with 3,000 P. projectus per 100 ㎤ of soil and non-inoculated. Treatments were replicated 10 times. After 100 days, the reduction of fresh top weight was 30.4% in C. intybus, 35.1% in I. aquatica, 36.9% in B. oleracea var. acephala, 40.5% in C. endivia, 42.1% in B. rapa, 47.5% in B. rapa subsp. nipposinica, 50.4% in B. oleracea var. gonglodes, 56.3% in B. oleracea var. italica, and 66.0% in B. juncea. Nematode multiplication rates (Pf/Pi) were lower in I. aquatica (0.64) and C. endivia (1.1), but higher in B. oleracea var. gongylodes (2.54). Considering these results, I. aquatica is suitable for the rotation crop with lettuce until better rotation crops developed.

• Journal of Digital Convergence
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• v.19 no.11
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• pp.575-583
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• 2021

This study aims to analyze Taekwondo trends according to news articles by year by applying topic modeling. In order to examine the Taekwondo trend through media reports, articles including news articles and Taekwondo specialized media articles were collected through Big Kinds of the Korea Press Foundation. The search period was divided into three sections: before 2000, 2001~2010, and 2011~2020. A total of 12,124 items were selected as research data. For topic analysis, pre-processing was performed, and topic analysis was performed using the LDA algorithm. In this case, python 3 was applied for all analysis. First, as a result of analyzing the topics of media articles by year, 'World' was the most common keyword before 2000. 'South and North Korea' was next common and 'Olympic' was the third commonest topic. From 2001 to 2010, 'World' was the most common topic, followed by 'Association' and 'World Taekwondo'. From 2011 to 2020, 'World', 'Demonstration', and 'Kukkiwon' was the most common topic in that order. Second, as a result of analyzing news articles before 2000 by topic modeling, topics were divided into two categories. Specifically, Topic 1 was selected as 'South-North Korea sports exchange' and Topic 2 was selected as 'Adoption of Olympic demonstration events'. Third, as a result of analyzing news articles from 2001 to 2010 by topic modeling, three topics were selected. Topic 1 was selected as 'Taekwondo Demonstration Performance and Corruption', Topic 2 was selected as 'Muju Taekwondo Park Creation', and Topic 3 was selected as 'World Taekwondo Festival'. Fourth, as a result of analyzing news articles from 2011 to 2020 by topic modeling, three topics were selected. Topic 1 was selected as 'Successful Hosting of the 2018 Pyeongchang Winter Olympics', Topic 2 was selected as 'North-South Korea Taekwondo Joint Demonstration Performance', and Topic 3 was selected as '2017 Muju World Taekwondo Championships'.