• Journal of Welding and Joining
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• v.22 no.4
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• pp.65-72
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• 2004

The aim of this study is to investigate the optimum drawing parameter for BAS111 welded tubes. The BAS111 aluminium alloy tubes with 25.4mm in external diameter and 1.5mm in thickness for heat-exchangers were manufactured by high frequency induction welding with the V shaped convergence angle 6.8$^{\circ}$ and power input 50㎾. With increasing the reduction of area (1.6, 5.8, 11.5, 14.2, 18.5, 22.5%) by drawing, tensile strength was increased and elongation was decreased. With increasing the reduction of area by drawing, hardness in weld metal increased rapidly, while that of base metal increased slowly. In the specimen with the outer diameter smaller than 22mm, hardness of weld metal was higher than that of base metal. The optimum drawing parameter of area reduction was estimated about 15% because of the work hardening of welds.

• Journal of The Korean Association For Science Education
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• v.31 no.5
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• pp.758-769
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• 2011

This study was designed to investigate the relations of motivation to related variables, and the motivation by student's variables basically through measure of motivation system about science learning. For this, 496 fourth-grade students and 425 eighth-grade students were required to accomplish a questionnaire on behavioral inhibition/activation system about science learning (SL-BIS/BAS), and self-efficacy. Based on these materials, SLBIS/BAS by student's variables and relations between the system to self-efficacy were analyzed. The result of this study shows the following:First, the sensitivity about SL-BIS in the eighth-grade was higher than in the fourth-grade. But sensitivity about SLBAS and self-efficacy in the eighth-grade was lower than in the fourth-grade Hence, the difference in sensitivity about SL-BIS/BAS agree with difference in motivation. Second, there were low negative correlation with SL-BIS and self-efficacy, and positive correlation with SL-BAS and self-efficacy. In addition, two systems account for 41% of self-efficacy, it showed that SL-BIS/BAS relates to self-efficacy. Through the results of this study, relations of motivation to related variables, and the motivation by student's variables were identified. These results would be helpful for teachers to understand the difference about motivation by students' variables and to make a plan for the appropriate strategies for learners.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.101-106
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• 1985

A series of experiments were carried out to know the effect of growth retardants on the growth of rice seedlings and ethylene evolution from the rice seedlings. The results suggested that the reduction rate in order of plant height was S-327 > BAS-106 > NTN-821 > PP-333 > CGR-811. The heigher concentration levels of growth retardants applied. the more effective reductions of plant height were found. Ethylene evolution from the rice seedlings was significantly negative correlated with plant hight of of seedlings in all treatments.

• Science of Emotion and Sensibility
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• v.8 no.1
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• pp.47-54
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• 2005

This study is aimed to inspect how the different sensitivities in Behavioral activation system(BAS) and behavioral inhibition system(BIS) modulate on the properties of physiological responses stimulated by positive or negative affective sound. We measured the electroencephalogram(EEG) and electrocardiogram (ECG) of 32 students, consisted of four groups depending on the BAS and BIS sensitivities, during listening to meditation music or noise. The EEG was recorded at Fpl and Fp2 sites and Power spectral density(PSD) of HRV was derived from the ECG, and the power of HRV was calculated for 3 major frequency ranges(low frequency[LF], medium frequency and high frequency[HF]). After listening to music or noise, subjects reported the affect induced by the sound. For EEG, the power in the alpha band at Fp2, especially in the alpha-2 band(9.0-11.0 Hz) increased during the subjects listening to music, while the power at Fpl increased during noise. During listening to meditation music, there is a tendency that the left-sided activation in prefrontal cortex(PFC) is positively correlated with the difference of BAS(Z)-BIS(Z). During listening to noise, there is a tendency that the right-sided activation in PFC is dominant in case any of the sensitivity of BAS or BIS is high. For HRV, we found that the index of MF/(LF+HF), during listening to music, was higher significantly in the individuals with a low BIS but high BAS than in the individuals with a low sensitivity both BIS and BAS individuals. With high BIS, regardless of the BAS sensitivity, the difference of this index values was not significant. From these results we suggest that the physiological responses of different individuals in BAS and BIS react differently under the same emotionally provocative challenge.

• International Commerce and Information Review
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• v.5 no.2
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• pp.113-132
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• 2003

The recent advancement of information technology bas impacted immensely on international trade. Particularly, the Internet revolution bas been the driving force behind the expansion of electronic commerce (e-commerce: EC), of which Trade e-Marketplace has been playing very important role in doing international trade. This study analyses its concept, features, types and present state, and also bas an outlook of it in the future based on a precedent and literature study on this subject in order that the trade business and small corporations understand more deeply and use it effectively.

• Journal of the Korean Ceramic Society
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• v.26 no.1
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• pp.132-138
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• 1989

High purity(99.99%) spherical particles of hydrated Basic Aluminum Salts(BAS) were prepared by a homogeneous precipitation process utilizing the urea decomposition reaction and characterized by XRD, SEM, TG-DTA, IR and PSA methods. Amorphous hydrated BAS was precipitated in the range of pH 4~6. The molar ratio [Al3+]/[SO42-] for the precipitate particles was about 3.7. With increasing the concentration of aluminum sulfate the precipitation of the hydrated BAS occurred slowly and the precipitate particles with a narrow size distribution were fine(1-2${\mu}{\textrm}{m}$ in diameter). At temperatures in the range 400$^{\circ}$to 95$0^{\circ}C$, desulfurization and dehydroxylization resulted in weight loss with 22%. When the precipitate particles were thermally treated, the crystlline ${\gamma}$-Al2O3 was identifited by XRD at 50$0^{\circ}C$ and ${\gamma}$-Al2O3 particles were transformed into $\alpha$-Al2O3 at 100$0^{\circ}C$. A vermicular network was produced by calcining at 125$0^{\circ}C$ for 30min.

• International Commerce and Information Review
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• v.6 no.2
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• pp.289-313
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• 2004

The European Union(EU) bas enacted a series of directives including the Directive on Electronic Commerce and started harmonizing the national laws in this area. As a result of this effort, Electronic, Commerce bas been vitalized as a part of Information Society Services. This article would be helpful to analyze the new legislations of the EU and to show their essentials as seeming free movement of goods and services by Electronic Commerce in the community. Therefore, this article would be useful to draw up a plan of South Korea Legislations on Electronic Commerce.

• Food Science of Animal Resources
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• v.43 no.1
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• pp.25-45
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• 2023

This study evaluated the antibacterial and antioxidant activities of ethanol extract of calamansi pulp (CPE) and its effect on quality and biogenic amine (BAs) formation in pork patties during storage. The CPE were prepared in various conditions (ethanol concentrations of 50%, 70%, and 90% with extraction periods of 3 and 6 days). The extract with potent antibacterial and antioxidant activities (90%, 6 days) was selected for addition to pork patties. Three groups were tested: Control (without extract addition), CPE addition at 0.2% w/w (0.2PCPE), and 0.4% w/w (0.4PCPE). The addition of CPE inhibited the formation of BAs, mainly cadaverine, histamine, and tyramine, in pork patties during storage. The pH and bacterial count of pork patties decreased significantly in a concentration-dependent manner following the addition of CPE. The instrumental color (CIE L^*, CIE a^*, and CIE b^*) tended to be higher in 0.4PCPE than in the control during storage. The thiobarbituric acid reactive substances and volatile basic nitrogen (VBN) values of pork patties were affected by CPE, showing a reduction toward lipid oxidation at any storage period, and maintaining the lowest VBN value in 0.4PCPE at the final storage day. Similarly, the reduction of total BAs in pork patties was observed ranged between 3.4%-38.1% under treatment with 0.2% CPE, whereas 18.4%-51.4% under 0.4% CPE addition, suggesting significant effect of CPE to improve meat quality. These novel findings demonstrate the efficacy of 0.4% CPE as a natural compound to preserve the quality and reduce BAs formation in pork patties during storage.

• Smart Structures and Systems
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• v.30 no.2
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• pp.195-207
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• 2022

Computational drawbacks associated with regular predictive models have motivated engineers to use hybrid techniques in dealing with complex engineering tasks like simulating the compressive strength of concrete (CSC). This study evaluates the efficiency of tree potential metaheuristic schemes, namely shuffled complex evolution (SCE), multi-verse optimizer (MVO), and beetle antennae search (BAS) for optimizing the performance of a multi-layer perceptron (MLP) system. The models are fed by the information of 1030 concrete specimens (where the amount of cement, blast furnace slag (BFS), fly ash (FA1), water, superplasticizer (SP), coarse aggregate (CA), and fine aggregate (FA2) are taken as independent factors). The results of the ensembles are compared to unreinforced MLP to examine improvements resulted from the incorporation of the SCE, MVO, and BAS. It was shown that these algorithms can considerably enhance the training and prediction accuracy of the MLP. Overall, the proposed models are capable of presenting an early, inexpensive, and reliable prediction of the CSC. Due to the higher accuracy of the BAS-based model, a predictive formula is extracted from this algorithm.

• Journal of The Korean Association For Science Education
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• v.32 no.4
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• pp.625-640
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• 2012

The purpose of this study was to investigate the behavioral characteristics of elementary second graders depending on SL-BIS/BAS (Behavioral Inhibition/Activation System about Science Learning) in science learning situation. For this study, 20 second grade students participated. This study followed a phenomenological research method, a form of qualitative research. As the results show, students who have a sensitive motivation system to SL-BIS directly expressed their disappointment of the result and easily get distracted in class when they failed in science learning activity. They participated in group work passively, for example, they interacted less in the group or avoided answering questions. Even though the students have a lot of questions that were usually simple, empty or repetitive words. They have within themselves the good will of challenging difficult experiment that was their only expression of passive will. The students have a tendency to be dependent on their friends in an experiment, making it unlikely that they preferred group work from the beginning. Otherwise, students who have sensitive motivation system to SL-BAS endured science learning activity to the end regardless of the negative result. In particular, they were enthusiastically working on home-school materials. When the students succeeded in the experiment, they responded to the cheers and openly expressed their feeling. They were satisfied with their achievement. The students have more desire for in-depth activity. Their questions were more progressive, specific and expanded. They showed a strong desire to challenge difficult experiment and preferred to interact with their group members to help each other. Based on the results, they were limited but we could find that the behavioral characteristics of second grade students in science learning situations can be predicted with a score of SL-BIS/BAS t.