• Korean Journal of School Psychology
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• v.17 no.3
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• pp.287-306
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• 2020

The purpose of this study was to investigate the effect of motivation promotion on task performance. Unlike most previous studies that have used survey methods, this study examined the effects of motivation promotion on arithmetic and linguistic task performances under experimental conditions. Effort-inducing instructions and positive feedbacks were used to promote participants' motivation. Experiments 1 and 2 examined the effect of effort-inducing instructions and positive feedback on participants' autonomous selection of task difficulty when performing arithmetic and linguistic tasks. The results of the both experiments showed that the experimental group which received effort-inducing instructions and positive feedback chose more difficult task than the control group did. Experiment 3 examined whether motivation promotion enhances task performance and task persistence. The experimental group was more accurate and persistent than the control group. The results of the current study offer experimental evidence suggesting that activating intrinsic motivation through motivation promotion improves attitudes toward tasks and task performance.

• Journal of Preventive Medicine and Public Health
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• v.28 no.2 s.50
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• pp.406-420
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• 1995

To study the health hazards and exposure status of manganese among female manganese workers, authors conducted airborne, blood and urine manganese concentration measurements, questionnaire and neurological examinations on 80 manganese-handling productive female workers(exposed group) in a manganese manufacturing facto in Pohang city and 127 productive female workers not handling manganese(control group) in other factories in the Pohang city. The results are; 1. Geometric mean concentrations of manganese in air and urine were $0.98mg/m^3\;and\;4.12{\mu}g/l$ and arithmetic mean concentration of manganese in blood was $6.94{\mu}g/dl$ in exposed group, significantly higher than those of control group(p<0.05). However, clinical and laboratory findings in exposed group were not statistically different from those of control group. 2. As age increase, positive rates of clinical symptoms also increased in the exposed group. However, in older aged group, the positive rates of symptoms and signs were statistically different from those of control group. We observed the same tendency in the positive rates of the neurological examinations. 3. There was statistically significant correlation between airborne and urine manganese concentrations(r=0.61, p<0.01) while there was no statistically significant correlation between airborne and blood manganese concentrations(r=0.29, p>0.05). The results suggest that urine manganese concentration was the best appropriate biomarker to estimate the exposure to manganese in respect to clinical symptoms and signs. In the analysis of correlation between urine and airborne manganese concentrations, it is required to adjust the present permissible exposure level(PEL) of airborne manganese.

• The Plant Pathology Journal
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• v.27 no.2
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• pp.128-137
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• 2011

Fifty two Macrophomina phaseolina isolates were recovered from 24 host plant species through the 14 Iranian provinces. All isolates were confirmed to species using species-specific primers. The colony characteristics of each isolate were recorded, including chlorate phenotype, relative growth rate at $30^{\circ}C$ and $37^{\circ}C$, average size of microsclerotia, and time to microsclerotia formation. The feathery colony phenotype was the most common (63.7%) on the chlorate selective medium and represented the chlorate sensitive phenotype of the Iranian Macrophomina phaseolina population. Meantime, inter simple sequence repeats (ISSR) Markers were used to assess the genetic diversity of the fungus. Unweighted pair-group method using arithmetic means (UPGMA) clustering of data showed that isolates did not clearly differentiate to the specific group according to the host or geographical origins, however, usually the isolates from the same host or the same geographic origin tend to group nearly. Our results did not show a correlation between the genetic diversity based on the ISSR and phenotypic characteristics. Similar to the M. phaseolina populations in the other countries, the Iranian isolates were highly diverse based on the phenotypic and the genotypic characteristics investigated and needs more studies using neutral molecular tools to get a deeper insight into this complex species.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.2
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• pp.265-272
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• 2009

Fuzzy number intuitionistic fuzzy sets (FNIFSs), each of which is characterized by a membership function and a non-membership function whose values are trigonometric fuzzy number rather than exact numbers, are a very useful means to describe the decision information in the process of decision making. Wang [10] developed some arithmetic aggregation operators, such as the fuzzy number intuitionistic fuzzy weighted averaging (FIFWA) operator, the fuzzy number intuitionistic fuzzy ordered weighted averaging (FIFOWA) operator and the fuzzy number intuitionistic fuzzy hybrid aggregation (FIFHA) operator. In this paper, based on the FIFHA operator and the FIFWA operator, we investigate the group decision making problems in which all the information provided by the decision-makers is presented as fuzzy number intuitionistic fuzzy decision matrices where each of the elements is characterized by fuzzy number intuitionistic fuzzy numbers, and the information about attribute weights is partially known. An example is used to illustrate the applicability of the proposed approach.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.2
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• pp.224-229
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• 2005

Generally, genetic algorithm (GA) has too much time and space complexity when it is running in the typical processor. Therefore, we are forced to use the high-performance and expensive processor by this reason. It also works as a barrier to implement real device, such a small mobile robot, which is required only simple rules. To solve this problem, this paper presents and proposes enhanced processor-architecture for the faster GA processing. A typical processor architecture can be enhanced and specialized by two approaches: one is a sorting network, the other is a residue number system (RNS). A sorting network can improve the time complexity of which needs to compare the populations' fitness. An RNS can reduce the magnitude of the largest bit that dictates the speed of arithmetic operation. Consequently, it can make the total logic size smaller and innovate arithmetic operation speed faster.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.73-80
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• 2020

The OECD surveys the questionnaire on the background of ICT every three years since 2003. In this study, we compare and analyze the changes in ICT accessibility and ICT usability of Korean students in 2015 and 2018 using the ICT background data of OECD PISA. ICT accessibility refers to the degree of access to ICT equipment at school or at home. There are 10 items of accessibility surveys at schools used by PISA, and 11 items at home. ICT usability refers to how much ICT equipment is used at or outside of school for learning or non-learning purposes. There are ten items for surveying usability at school, and twenty-four items for surveying usability outside of school. In the analysis of this study, the arithmetic mean of the items is used. As a result, Korean students' accessibility at school improved from 25.48% in 2015 to 40.40% in 2018, and from the lowest group in 2015 to below-average group in 2018. In terms of students' usability at school, we analyzed the percentage of students who use the ICT equipment 'almost every day' and the students who use it 'everyday'. Both 2015 and 2018 are among the lowest. Accessibility at home is higher in 2018 than in 2015, and belongs to the average group of OECD countries in 2018. ICT Usability for learning purposes outside of school is the lowest group in both 2015 and 2018. ICT Usability outside of school for non-learning purposes is in the average group of OECD countries. As a result of this study, we can see that Korea's digital literacy education is weak compared to other OECD countries. Prior to education about the Fourth Industrial Revolution, investment in digital literacy education is needed.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.3
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• pp.222-229
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• 1993

Total suspended particles in the atmosphere were collected on the quartz fiber filters using an ANdersen Hi-volume air sampler from March 1989 to October 1989 and from June 1990 to February 1991, at Chung-Ang University in Seoul. A total amount of eight heavy metals (Cr, Zn, Cd, Pb, Fe, V, Ti, Mn) in total suspended particles were determined by ICP spectrophotometer. The annual arithmetic mean concentration of total suspended particle was 162.3$\mug/m^3$ and eight metals(Cr, Zn, Cd, Pb, Fe, V, Ti, Mn) were 11.6, 609.2, 3.5, 337.1, 2739.5, 15.1, 89.4 and 100.5ng/$m^3$, respectively. The concentration of total suspended particle was highest in the spring(343.7$\mug/m^3$) and lowest in the summer(91.8$\mug/m^3$). These heavy metals were distinguished into two groups in terms of their particle size distribution. The contents of first-group heavy metals (Fe, Ti, Mn) were increased in accordance with the growth of the particle size. The contents of the second-group ones such as Pb, Cd, V, and Zn, on the contrary, came to increase according as the particle size reduced. Statistical analysis indicated that there was a correlation between total suspended particle and Fe in coarse particles, and between total Suspended Particle and Zn, Pb in fine particle.

• Korean Journal of Plant Taxonomy
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• v.50 no.3
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• pp.333-342
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• 2020

Despite poorly documented species delimitation and unresolved taxonomic nomenclature, four species of Symplocos (S. coreana, S purnifolia, S sawafutagi, and S. tanakana) have been described in Korea. In this study, we carried a comparative wood anatomy analysis of all four species of Korean Symplocos to understand the wood anatomical variations among them. The results of this study indicated that Korean Symplocos are comparatively indistinguishable in terms of their qualitative wood features, except for exclusively uniseriate rays present in S. purnifolia instead of uniseriate to multiseriate in other three species. Nevertheless, differences are noticed in quantitative wood variables such as the vessel density, vessel size, and ray density. The vessel density of S. purnifolia is more than twice as high as those of S. sawafutagi and S. tanakana. In contrast, the vessel circumference and diameter on both plants of S. sawafutagi and S. tanakana is nearly twice as large as those of S. purnifolia. Symplocos coreana has characteristic intermediacy between these two groups in terms of vessel features and is closer to S. purnifolia in terms of its ray density level. A cluster analysis based on a paired group (unweighted pair-group method with the arithmetic mean, UPGMA) algorithm using the Euclidean similarity index clearly differentiates S. purnifolia from the remaining species, representing the first branch of the phenogram.

• Journal of Microbiology
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• v.43 no.5
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• pp.383-390
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• 2005

The diversity of the denitrifying bacterial populations in Daejeon Sewage Treatment Plant was examined using a culture-dependent approach. Of the three hundred and seventy six bacterial colonies selected randomly from agar plates, thirty-nine strains that showed denitrifying activity were selected and subjected to further analysis. According to the morphological and biochemical properties, the thirty nine isolates were divided into seven groups. This grouping was supported by an unweighted pair group method, using an arithmetic mean (UPGMA) analysis with fatty acid profiles. Restriction pattern analysis of 16S rDNA with four endonucleases (AluI, BstUI, MspI and RsaI) again revealed seven distinct groups, consistent with those defined from the morphological and biochemical properties and fatty acid profiles. Through the phylogenetic analysis using the 16S rDNA partial sequences, the main denitrifying microbial populations were found to be members of the phylum, Proteobacteria; in particular, classes Gammaproteobacteria (Aeromonas, Klebsiella and Enterobacter) and Betaproteobacteria (Acidovorax, Burkholderia and Comamonas), with Firmicutes, represented by Bacillus, also comprised a major group.

• Journal of Educational Research in Mathematics
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• v.8 no.1
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• pp.137-144
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• 1998

A common geoboard puzzel serves as the point of departure for an investigation that lends itself to whole-group discussion with a class of prospective secondary school teachers. Students are provided with opportunities to devise and carry out problem-solving strategies (called 'heuristics' by Polya); exploit inerrelationships among geometry, arithmetic and algebra; formulate generalizations and conjectures; plan and execute an computational project; construct mathematical arguments to establish theorems; and find counter-examples to dispose of a false conjecture. In recent tears, Eugene F. Krause wrote two papers having the same title except for the numeral In that papers he arrives at an theorem about the sizes of squares with lattice point vertices in the coordinate plane, In this paper we follow a different path genearlization to coordinate 3-space