• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.103-111
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• 2008

This study was carried out to investigate the optimal application rate and time of mixed expeller cake (MEC) for the replacement of chemical fertilizer. Dongjin-1, as cultivated rice was used at Fluvio-marine deposit in Honam plain paddy field. Soil chemical properties were improved by the application of MEC. Contents of total nitrogen and organic matter were higher in 70%, 100% plots of basal dressing than standard fertilizer application (SFA) plot. Cation exchangeable capacity was highly increased in 70% plot of basal dressing. Also, the content of organic matter in soil was increased with MEC application. Cation exchangeable capacity, total nitrogen and available phosphate were decreased according to late application time. The content of inorganic nitrogen in soil showed high tendency at more application rate of MEC, and nitrogen mineralization at harvest season have finished in 50%, 70% plots of basal dressing. The content of inorganic nitrogen in soil was increased according to late application time, however it was decreased in the late period of growth. Leaf color value became darker with increased application rate of MEC. Leaf color was dark green in MEC application plots at panicle formation stage, on the other hand, it was light green in 50%, 70% plots of basal dressing at heading stage. SPAD reading value of leaf-color was high during the whole growth stage in MEC application plots. More application rate of MEC showed higher tendency of fertilizer nitrogen absorption. Nitrogen use efficiency was the highest in 70% plot of basal dressing. Absorbed amount of fertilized nitrogen was increased in 10~15days before transplanting and nitrogen use efficiency was high according to the late application time. The ratio of perfect kernel and the content of protein on hulled rice showed high tendency at the less application rate of MEC. The ratio of head rice on milled rice showed high tendency at the less application rate of MEC. Rice yield increased 4% in 100% and 70% plots of basal dressing compare with SFA ($5.18Mg\;ha^{-1}$) plot respectively. Ear and culm length of rice were long according to the late application time, while the numbers of spikelet and ear were increased and the percentage of ripened grain was decreased. Rice yield was increased 2~5% in all MEC application plots compared to SFA plot and especially, increased 10~15days before transplanting in application plots. The optimal application rate and time of MEC on normal paddy field in plain were concluded that 70% basal dressing and 10~15days before transplanting

• Journal of the Korean Chemical Society
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• v.68 no.2
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• pp.93-106
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• 2024

This study investigated differences in presence, immersion, and situational interest in small group learning using augmented reality, based on the degree of tool sharing. 84 eighth-grade students participated in small groups of four. Each group was randomly assigned to one of three environments based on marker and device sharing: the shared environment (shared marker and device usage), the mixed environment (shared marker and individual device usage), and the individual environment (individual marker and device usage). Small group learning using augmented reality was conducted for three class periods, focusing on the "Characteristics of Matter" unit. One-way ANOVA results for the dependent variables revealed that, compared to the shared environment, presence and situational interest were significantly higher in the mixed environment, while immersion and situational interest were significantly higher in the individual environment. MANOVA results for the sub-components of each dependent variable showed significant differences in realness for presence, antecedents and experiences for immersion, and instant enjoyment, novelty, and total interest for situational interest. Analysis of interviews and classroom observations indicated that students in shared and individual environments tended to use their devices individually when utilizing augmented reality. However, in mixed environments, students showed a tendency to use their devices collaboratively, leading to more active interactions. Based on these findings, environments for using tools to enhance the effectiveness of small group learning using augmented reality are discussed.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.17-24
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• 2017

PURPOSES : This study aims to develop a sealant for use in the installation of Weigh-In-Motion (WIM) sensor for asphalt concrete or cement concrete pavements. METHODS : In order to investigate the properties of various sealants that were mixed with latex and carbon fiber, various test methods were adopted, such as bituminous bond strength test, softening point test, and cone penetration test. To evaluate moisture susceptibility, the BBS test was conducted under moist condition. The bond strength ratio (BSR) was calculated based on tensile strength ratio method. RESULTS : The sealant's properties significantly varied according to the amount of latex or carbon fiber. The usage of latex marginally enhanced the cone penetration test result, notwithstanding reduced asphalt content. This implies that the sealant will be proper cold temperature reason. Moreover, the addition of latex and carbon fiber evidently increased the softening point. This indicates that the tendency of the material to flow at elevated temperatures is encountered during service. With the addition of latex and carbon fiber, the moisture susceptibility measured with BSR improved marginally, while the bond strength under dry condition decreased marginally. Sealant F displays the highest bond strength and BSR under limited test conditions. CONCLUSIONS : According to the proportion of latex and carbon fiber mixed, properties of sealant, such as softening point, cone penetration, and BSR varied marginally. This indicates that the sealant has to be applied considering the environmental condition, to improve service life.

• Journal of the Korea Concrete Institute
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• v.11 no.3
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• pp.123-130
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• 1999

In a preceding study(1), the using method of garnet powder has been studies through the various investigation of basic material properties on garnet powder, industrial by-products generated in Yungju, Kyungpook. In this study, the various properties of concrete mixed with garnet powder are examined as following condition : Unit weight of water (170kg/㎥), water-binder ratio W/B (53, 55 and 58%), sand-aggregate ratio (S/A) (43, 45 and 48%), substitutional ratio of garnet powder of 0, 5, 10, 15 and 20%. Slump increased a little as the substitutional ratio of garnet increased. Air content decreased a little at the substitutional ratio of 10%. or more. Though there is a little difference in compressive strength according to the W/B and the substitutional ratio, compressive strength of concrete using garnet exceeded that of plain concrete a little in the range of the substitutional ration of 5 to 15%. Also, There is a similar tendency in the tensile and flexural strength. Therefore, the use of garnet powder with industrial by-products is expected to improve the workability and the strength of concrete.

• Journal of the Korean Wood Science and Technology
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• v.47 no.1
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• pp.66-79
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• 2019

The aim of the study is to use the by-products sawdust, formed during sawing and mandarin peel which are agricultural by products. The boards were manufactured by mixing the sawdust and mandarin peel at different mixing ratio and density. In terms of changes in surface temperature of ceramics, we could found that the velocity was fast in the early time of heat transfer until 10 minutes and after that the velocity increased but not very fast. At the elapsed time of 30 minutes, the surface temperature of ceramics increased with the carbonization temperature and rate of mandarin peel addition did not influence the surface temperature. Far - infrared emissivity had no constant tendency in rate of mandarin peel addition, it decreased with increase of carbonization temperature.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.461-472
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• 2020

In recent decades, the research field of entrepreneurship phenomenon has significantly increased in both quantity and sophistication. In Vietnam, paradoxically, while creating a new business venture has become a tendency, the interest in studying entrepreneurs seems not to be thoroughly investigated. This research aims to evaluate the factors that affect the entrepreneurial intention of information technology (IT) students in Vietnam. The authors make use of mixed methods including both quantitative research method and qualitative research method. The qualitative research method is employed to identify meanings, confirmations, adjustments, and compliments for concept-measurement variables in the conceptual model. Quantitative research is conducted from a sample of 424 IT senior students across many universities in Vietnam. Questionnaires have been sent to students to evaluate the measurement scale and appropriateness of the research model. Results from multiple regression highlighted five independent variables affecting the dependent variable, the entrepreneurial intention, in a descending order as following: entrepreneurial educational environment, personal characteristics, perception of feasibility, entrepreneurial supports, and financial accessibility. In addition, this research has proved that the variable attitudes towards entrepreneurship partially mediated among the interrelationship of the aforementioned variables. From this research, the authors make some recommendations to enhance entrepreneurial intentions of IT students in Vietnam.

• The Journal of Fisheries Business Administration
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• v.45 no.3
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• pp.111-129
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• 2014

The main purpose of this study is to analyze the disputes concerning the 1982 moratorium on commercial whaling and the standing rights of other natural objects. Basically, the debates has arisen from the very nature of whales and other natural resources, that is to say, a mixed good of consumptive and non-use value. The debates between pro- and anti-moratorium states regarding whaling may not find out a peaceful solution without compromise or negotiation since any international institution for official settlements does not exist. If the pro-states could provide anti-states with a certain type of economic incentive which is side payments, anti-states might offer self-restraint not to whale. Here, it would be considered to apply Kaldor-Hicks compensation principles to this problem. Since 1965, some countries such as the United States and Japan began to recognize the standing right of natural objects. Even though rejected, the newt case in Korea was brought to the Supreme Court. If a standard of living increases significantly to a higher level(i.e. more than per capita income US$30,000), there would be a tendency of valuing natural objects and their beauty more and more highly.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.6
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• pp.672-680
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• 2007

Apparatus of rotating disk and cup are widely used spray paintings and industrial boilers. This study was conducted experimentally to investigate the characteristics of liquid atomization in a rotating disk atomizer by means of viscous liquid mixed water and glycerin. The Purpose of this study are to observe breakup mechanism according to the variation of supplied flow rate $0.4{\sim}30 cm^3/s$ and rotating speed $200{\sim}4000rpm$, and to investigate three kinds of breakup Pattern such as drop ligament and film formation by comparing the transition flow rate. ligament number and ligament length to those of Tanasawa and Matsumoto's empirical formula. The results are as follows ; The higher it makes use of viscous liquid. the better it get the characteristics of breakup mechanism. Also When I compared practical value with experiential value at similar test conditions. it was shown similar tendency though were a little variation.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.5
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• pp.489-500
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• 2012

This work surveys the trend and dissolution characteristics in headdress that appear in Jean Paul Gaultier's collection. Along with a related literature review, a total of 903 headdress pieces shown in collections 40 times (excluding the common caps and hats) were analyzed, covering from 2001S/S to 2010 F/W of Jean Paul Gaultier's Haute Couture and Pret-a-Porter. The headdress trend indicated in his collections was divided into such subgroup forms of folklore, usage of natural things, usage of artificial things, religion, retro, scarf, variations in headgear, mask and veil, atypical type and abstract. Such an expression tendency was so unique and mixed characteristic that it was hard to define its form and structure thanks to enlargement and exaggeration, extremity in ornaments, and use of foreign materials, which led to creative dynamics. Gaultier's headdress also reflected the following characteristics: first, expression of difference indicative of time deconstruction; second, uncertainty of meanings via deconstruction; third, text interactivity via deconstruction of gender and material adopted; fourth, decentralization through dissolution of the Orient and the Occident.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.2075-2089
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• 2008

Improvement of transport system is necessary to advance the freight traffic meanwhile logistics are getting bigger and faster by worldwide tendency. The link between each transportations occurs bottleneck state and it raises the necessity of non-stop mixed transport system which can reduce the cost of logistics. DMT(Dual Mode Trailer) was designed to use road and railway at the same time for door to door service. It is called DMT for every transport system which can connect between road and railway in Korea. This study would like to examine the present condition of promotion for localization of DMT which is new idea and technology and suggest the new subjects from now.