• Journal of Educational Research in Mathematics
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• v.15 no.2
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• pp.177-196
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• 2005

In the Korean curriculum, students learn the concept of sample, sampling and other concepts related to sample and sampling, when they have reached the 10th grade of high school. But before the 10th grade, they have an activity about data collection, data analysis and the formulation of conclusion. We then investigated and analyzed the informal knowledge of students before they receive formal instructions. The results enabled the identification of the maximum response rate for each question that each student agreed or disagreed with. In particular, it didn't agree with how students consider the characteristic of population in the process of sampling, and the students agreed on a sampling process without considering the characteristic of the population or the components that consist the population. It showed that 5th grade students didn't investigate the data connected with sampling, and didn't understand the validity of sample survey process. While, 6th grade students equally understood sample size, sampling process, the reliance of data acquired through sample survey that applied to the source of judgment. But in details, it revealed that student had a misconception, or stayed at a subjective judgment level. The significant point is that many high school students didn't adequately understood a sample size with sampling. Though statistics instruction has traditionally been delayed until upper secondary education, this inquiry convinced us that this delay is unnecessary.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.335-344
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• 2020

This study compared the structures and changes of help network between pre-service secondary teachers and pre-journalists who participated in the class related to network analysis to seek ways to activate a professional learning community. For this study, we used Exponential Random Graph Models (ERGM) based on ties as being interdependent and not conventional regression models requiring assumptions of independence between observations. The analysis subjects were 43 pre-service secondary teachers and 29 pre-journalists who responded both early and late in the help network survey. The main results were as follows. First, full models with network structural terms were better than simple models with no structural terms. Second, the effect of transitivity was not statistically significant in the pre-service secondary teachers' network. However, it was statistically significant in the pre-journalists' network. Third, there were effects of reciprocity, indegree popularity, and outdegree activity in the early help network of pre-service secondary teachers. On the contrary, there were only the positive effects of reciprocity and the negative effect of outdegree activity in the late network. Finally, this study demonstrated the possibility in educational fields' application of network structural effects and provided limitations and directions for future research.

• Journal of Embryo Transfer
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• v.19 no.3
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• pp.291-299
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• 2004

Characterization of quantitative trait loci (QTL) was investigated in the experimental cross population between Berkshire and Yorkshire breed. A total of 512 F$_2$ offspring from 65 matting of F$_1$ parents were phenotyped the carcass traits included average daily gain (ADG), average backfat thickness (ABF), tenth rip backfat thickness (TRF), loin eye area (LEA), and last rip backfat thickness (LRF). All animals were genotyped for 125 markers across the genome. Marker linkage maps were derived and used in QTL analysis based on line cross least squares regression interval mapping. A decision tree to identify QTL with imprinting effects was developed based on tests against the Mendelian mode of QTL expression. To set the evidence of QTL presence, empirical significance thresholds were derived at chromosome-wise and genome-wise levels using specialized permutation strategies. Significance thresholds derived by the permutation test were validated in the data set based on simulation of a pedigree and data structure similar to the Berkshire-Yorkshire population. Genome scan revealed significant evidences for 13 imprinted QTLs affecting growth and body compositions of which nine were identified to be QTL with paternally expressed inheritance mode. Four of QTLs in the loin eye area (LEA), and tenth rip backfat thickness (TRF), a maternally expressed QTL were found on chromosome 10 and 12. These results support the useful statistical models to analyse the imprinting far the QTLs related carcass trait.

• Journal of forensic and investigative science
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• v.1 no.2
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• pp.20-30
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• 2006

An exhibitional suicide is a case of death that the purpose is to demonstrate one's own real intention for others. This exhibitional suicide has a few characteristics that are different from a suicide: seriousness of suicide intention, a method of suicide attempt, and the place of a suicide. In other words, an exhibitional suicide lacks suicide intention, uses a slower method of death, and attempts a suicide at the place which others can easily find. In this light, this paper ascertains that a fair number in poisoning deaths are an exhibitional suicide on the basis of the result of an autopsy by department of forensic medicine school of medicine, Kyungpook National University. The research also confirms that juveniles and women attempt a suicide as often as adults and men, and a great number of suicides are indeed an exhibitional suicide. In terms of a commercial law, many specialists see an exhibitional suicide as an accidental death. However, if we consider an exhibitional suicide as an accidental death, we cannot verify the authenticity of death in an accident. In addition, if we observe the purpose of insurance and suicide exemption period of insurance company, we rather get to know to distinguish an exhibitional suicide from an accident. According to the research, most of the exhibitional suicide results from little or no-relation with others. Therefore, a little interest from family, friend, and neighbor plays a pivotal role in preventing this suicide. Finally, an effort to build database concerning an exhibitional suicide by a psychological autopsy will help people access a plenty of statistical materials and facilitate further study about an exhibitional suicide.

• The Korean Journal of Applied Statistics
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• v.29 no.1
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• pp.85-98
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• 2016

This study makes an empirical comparison of various realized volatilities (RVs) in terms of overnight returns. In financial asset markets, during overnight or holidays, no or few trading data are available causing a difficulty in computing RVs for a whole span of a day. A review will be made on several RVs reflecting overnight return variations. The comparison is made for forecast accuracies of several RVs for some financial assets: the US S&P500 index, the US NASDAQ index, the KOSPI (Korean Stock Price Index), and the foreign exchange rate of the Korea won relative to the US dollar. The RV of a day is compared with the square of the next day log-return, which is a proxy for the integrated volatility of the day. The comparison is made by investigating the Mean Absolute Error (MAE) and the Root Mean Square Error (RMSE). Statistical inference of MAE and RMSE is made by applying the model confidence set (MCS) approach and the Diebold-Mariano test. For the three index data, a specific RV emerges as the best one, which addresses overnight return variations by inflating daytime RV.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.3
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• pp.77-84
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• 2015

The key objective of this research is to review the effectiveness of spatial regression to identify the influencing factors of spatial distribution patterns of floating population. To this end, global and local spatial autocorrelation test were performed using seoul floating population survey(2014) data. The result of Moran's I and Getis-Ord $Gi^*$ as used in the analysis derived spatial heterogeneity and spatial similarities of floating population patterns in a statistically significant range. Accordingly, Geographically Weighted Regression was applied to identify the relationship between land use attributes and population floating. Urbanization area, green tract of land of micro land cover data were aggregated in to $400m{\times}400m$ grid boundary of Seoul. Additionally public transportation variables such as intersection density transit accessibility, road density and pedestrian passage density were adopted as transit environmental factors. As a result, the GWR model derived more improved results than Ordinary Least Square(OLS) regression model. Furthermore, the spatial variation of applied local effect of independent variables for the floating population distributions.

• Cartoon and Animation Studies
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• s.26
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• pp.31-56
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• 2012

This is a scientific study of subjectivity on recognition types and preferences of animation audience. Therefore, Q-methodology was used as a methodology of this study. As a result, it was possible to find the various characteristics according to the preferences of audience on animation genres. The features of each type were classified into 3 types. First was an artistic and literary value-oriented type that explored storytelling and descriptive value. Second was a pictorial and aesthetic value-oriented type that explored visual beauty such as characters and Mise en scene. Third was a visual and entertainment value-oriented type that explored entertainment factors and attractions. Thus, according to the classification of preference types, it was inferred that digital image generation audience with an active preference that can create and consume images have developed a tendency that independently consumed their preferences based on thoroughly personal or subjective preferences rather than classified and accepted their preferred culture as their symbolic expressions of hierarchical position. In this aspect, Q-methodological consideration that is useful to analyze the subjectivity of audience could be a significant work. Nevertheless, this study alone could not reveal various generative contexts of specific preferences. It seems to have more significant results by applying various qualitative or quantitative methodologies together with this study and analyzing recognition types and preferences of audience.

• Korean Journal of Culture and Social Issue
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• v.19 no.2
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• pp.159-178
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• 2013

The purpose of this study was to 1) replicate the Wells effect(i.e., reluctance to rule against the Defendant solely on the basis of probabilistic evidence) in Korea and 2) examine the validity of an Alternative explanation(i.e., perception of risk of wrong verdict). In study 1(n=46), mock jurors in the tire-tracks condition were reluctant to rule against the defendant based on their perceived probability and this pattern was not resulted in the tire-tracks-belief condition. Therefore, the Wells effect was replicated in Korea. In study 2(n=70), we manipulated the participants' perception of risk of wrong verdict. That is, participants who were assigned in the high risk perception of wrong verdict were informed that if the defendant were found guilty, the defendant would get considerable demage both in finance and reputation of the company. Participants in the low risk perception of wrong verdict condition were informed that these demage would not be great. The results revealed that the Wells effect was pronounced in the high risk perception of wrong verdict condition. That is, participants were more reluctant to rule against the defendant when they perceive the significance of the result of wrong verdict as high. Limitations of the study and the directions for future study were discussed.

• Clinical and Experimental Pediatrics
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• v.45 no.2
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• pp.240-246
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• 2002

Purpose : It is not clear that the development of glomerular injury and aggravation by tumor necrosis factor alpha($TNF-{\alpha}$) is related to intrarenal or serum concentration of $TNF-{\alpha}$. So, we studied the relationship between the concentration of $TNF-{\alpha}$ and aggravation of glomerular damage in the Henoch-$Sch{\ddot{o}}nlein$ nephritis(HSN) and idiopathic nephrotic syndrome(INS). Methods : We collected the sera and urines of 21 patients with Henoch-$Sch{\ddot{o}}nlein$ purpura(HSP) and 22 patients with INS visited Chungbuk National University hospital from March 1998 to March 2001. The concentration of $TNF-{\alpha}$ in the sera and urines were measured by sandwich ELISA. Results : Serum $TNF-{\alpha}$ levels in the HSP patients with renal involvement were significantly higher than those without renal involvement(P=0.009). But urine $TNF-{\alpha}$ levels have no correlation with renal involvement(P=0.088). In the HSN patients, proteinuria have a significant correlation with serum $TNF-{\alpha}$ levels(P=0.004) but less correlation with urine $TNF-{\alpha}$ levels(P=0.053). Otherwise, proteinuria have no correlation with serum $TNF-{\alpha}$ levels(P=0.763) but have a significant correlation with urine $TNF-{\alpha}$ levels(P=0.007) in INS. Conclusion : These result suggest that the serum concentration of $TNF-{\alpha}$ would be important to glomerular involvement in HSP. And, it is interesting that proteinuria shows a significant relation with serum $TNF-{\alpha}$ levels in the HSN, but with urine $TNF-{\alpha}$ levels in the INS. This means the major production of $TNF-{\alpha}$ may be originated by extrarenal inflammation in the HSN and by intrarenal tubulo-interstitial damage due to proteinuria in the INS.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.292-300
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• 2013

In this study, we examine the palatability and physicochemical properties of rice in the year, when there was 10% increase in yield compared to normal year due to daily temperature range and sunshine hours. The results of the analysis of rice yield over the last 20 years (1993-2012) showed 10% difference between the yield in 2000, which was normal, and that in 2001. With regard to the crop weather condition during the ripening period in 2001 compared to 2000, the daily range and sunshine hours were higher, but the mean temperature was similar. The rice yield in 2001 was 9.8% higher than that in 2000 due to the increased number of spikelets per panicles and ratio of ripened grain. In terms of chemical traits, protein, Mg, and K contents decreased in 2001 compared to 2000, but amylose content increased. Trough and final viscosity assessed with a Rapid Visco Analyser were significantly higher in 2001 than 2000. The quality of cooked rice was measured through the Toyo Mido Meter Glossiness Value (TGV) instead of a palatability score because a sensory test produces relative comparison values rather than absolute values. The correlation coefficients between the sensory evaluation parameters and the TGV in several rice materials harvested in two years showed a highly significant positive correlation ($r=0.81^{**}-0.89^{**}$, n=27-47). TGV was also significantly higher in 2001 than in 2000. The results suggested that the palatability of cooked rice was good in 2001 with about 10% increase in rice yield compared to normal year in 2000 due to daily temperature range and sunshine hours.