• Journal of the Korea Concrete Institute
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• v.20 no.5
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• pp.619-626
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• 2008

There have been numerous studies to develop eco-friendly concrete. The attempt to reduce the amount of cement usage is suggested as one of the solutions for eco-friendly concrete. To reduce the amount of cement usage, the pozzolan-reaction materials such as ground granulated blast furnace slag, fly ash, and meta kaolin are widely used as the mineral admixture. Hwangtoh which deposited broadly in Korea is a well known eco-friendly material and the activated Hwangtoh with pozzolan-reaction can be practically used as a mineral admixture of concrete. Meanwhile, PET fiber made of recycled PET bottle is a type of recycled material, which can be used to control micro cracks in concrete. But the study about concrete mixed with recycled PET fiber is insufficient and the research of Hwangtoh concrete mixed with PET fiber is urgently needed presently. In this study, experiment and analysis flexural behavior of Hwangtoh concrete blended with recycled PET fiber are carried out. The results are discussed in detail.

• Journal of the Korean Ceramic Society
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• v.29 no.5
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• pp.347-356
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• 1992

Various kaolin samples with different alumina content were prepared from calcined admixture of kaolin and ammonium sulfate by varying the treatment time in sulfuric acid. Samples were nitridated under N2 or N2-H2 atmosphere with changing the amount of added carbon, the reaction time and temperature. As the alumina content lowered, the size of kaolin particles decreased and the specific surface area increased. XRD analysis indicated that ${\alpha}$-quartz remained by decomposition of halloysite and meta-halloysite. Experimental results of nitridation behavior are summerized as follows; 1) Nitridation under N2 atmosphere. With the increase of C/SiO2 ratio and with the decrease of Al2O3 content, disappearance of XRD pattern peaks of mullite, ${\alpha}$-quartz and ${\alpha}$-Al2O3 were accelerated at 1300$^{\circ}C$. SiC was the main phase in the reaction product of acid-treated kaolin samples nitridated at 1300$^{\circ}C$ for 10 hours regardless of C/SiO2 ratio. But the XRD peak intensities of ${\beta}$-Si3N4, ${\beta}$-sialon and SiC did not show much difference when untreated raw kaolin was fired at the same condition. When the ratio of C/SiO2 was 3.5, ${\beta}$-sialon and ${\beta}$-Si3N4 existed in the reaction product of about 22% alumina containing kaolin sample fired at 1350$^{\circ}C$ for 7 hours. Only ${\beta}$-sialon existed in the same sample fired at 1400$^{\circ}C$ for 10 hours. ${\beta}$-sialon was obtained from all of the acid-treated kaolin samples fired at 1400$^{\circ}C$ for 40 hours, but AlN and SiC remained in the untreated kaolin sample. Z value of the ${\beta}$-sialon obtained from the 22% alumina containing kaolin sample fired at 1400$^{\circ}C$ for 40 hours was about 1.3(XRD) and 1.5(EDS). 2) Nitridation under 80N2+2OH2 mixed gas atmosphere with the C/SiO2 ratio of 1 Mullite was not found, but ${\alpha}$-Si3N4, and ${\beta}$-sialon were present in the reaction product of about 22% alumina containing kaolin sample fired at 1300$^{\circ}C$ for 10 hours. When untreated kaolin sample was nitridated at the same condition, mullite remained. AlN and SiC were not found in the reaction product of about 22% alumina containing kaolin sample fired at 1350$^{\circ}C$ for 5 hours. On the other hand, AlN and SiC remained in the product of untreated kaolin fired at the same condition.

• Journal of the Korean School Mathematics Society
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• v.9 no.3
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• pp.249-263
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• 2006

The purpose of this study is to investigate the characteristics of 'best practire' in mathematics and suggest some solutions to several problems emerging in mathematics classes of secondary schools. The study was carried out by using qualitative research methods such as class observations and in-depth interviews with six teachers. Based on the collected data, we could sort out the major patterns which characterize 'the good mathematics teaching' at schools in Korea. The common characteristics of best practice in mathematics are drawn out from the six cases. The common characteristics include revising the curriculum and text books, realistic mathematics education, using ICT and meta-cognition, introduction with motivation and interest, performance assessment and managing differentiated small group. Results implied that six teachers used a variety of instructional methods and strategies which is related with the common characteristics of good mathematics teaching. Also these teachers not only improved their own classroom practices but also participated in various professional community of mathematics education and shared their practical knowledge. In conclusion assorted efforts from the government and the school principals as well as the teachers are prerequisite for practicing and spreading good mathematics teaching across the classrooms.

• Korean Journal of Psychosomatic Medicine
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• v.25 no.1
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• pp.19-26
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• 2017

Objectives : The aim of this meta-analysis study was to examine the relationship between cognitive anxiety and performance in closed loop skill sports. Methods : A comprehensive literature search was conducted using databases including Korean Information Service System, DBpia, Research Information Sharing Service, and National Assembly Library from 1980 to 2015. Search terms included 'Golf', 'Shooting', 'Archery', 'Anxiety', and 'Performance'. Standardized mean difference and 95% CI(confidence intervals) were calculated, and the heterogeneity of the studies was estimated using Q statistic. Results : Ten studies have satisfied the inclusion criteria. The main findings indicate that cognitive anxiety was significantly reverse correlated with performance in closed loop skill sports(r=-.198). The mean effect size for men(r=-.31) was significantly greater than that for women(r=-.05). Conclusions : Our results suggest that cognitive anxiety in closed loop skill sports is correlated with performance of athletes. Future study related to psychological aspects on athletes in sports is required in order to understand the specific evidence of relationship between anxiety and performance.

• Journal of Korean Traditional Oncology
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• v.23 no.1
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• pp.1-14
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• 2018

Objectives: This study was conducted towards developing guidelines of herbal medicine treatment for gastric cancer. Methods: We performed a systematic review and meta-analysis designed to investigate the efficacy of herbal medicine treatment for gastric cancer on four cancer questions; survival rate, metastasis, immune function, and quality of life. Based on the findings, we utilized a two-round delphi process with panel of 22 experts for their level of agreement. Results: Combined therapy group, herbal medicine treated with chemotherapy, was significantly higher in the 1-year survival rate (RR=1.27, 95% CI: 1.14 to 1.40, P=0.005, $I^2=71%$) and 3-years survival rate (RR=1.41, 95% CI: 1.16 to 1.71, P=0.91, $I^2=0%$) than chemotherapy group. The suppression of metastasis was higher in the combined therapy group (RR=0.62, 95% CI: 0.45 to 0.84, P=0.09, $I^2=54%$). The immunology function was higher in the combined therapy group compared with the chemotherapy group (MD=16.43, 95% CI: 13.25 to 29.61, P<0.001, $I^2=99%$). The quality of life score was higher in the combined therapy group compared with the chemotherapy group (RR=1.55, 95% CI: 1.21 to 2.00, P<0.66, $I^2=0%$). Conclusions: Among the Randomized controlled trials (RCT) included, the levels of survival rates, suppression of metastasis, immune function, and quality of life of the group treated with chemotherapy were lower compared to those treated with herbal medicine in addition to chemotherapy.

• The Journal of the Korea Contents Association
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• v.13 no.3
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• pp.211-217
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• 2013

A body dysmorphic disorder refers to a state that individuals whose external appearance is normal consider their appearance to be meta-morphosed, or think there's something wrong with it, or view a trifle deficiency as severely disfigured. The purpose of this study was to examine the body dysmorphic disorder and depression of health-related and health-unrelated majors in an effort to compare the two groups. And it's also meant to investigate the relationship between body dysmorphic disorder and depression. The subjects in this study were 400 students at K college located in Gangwon Province. Out of them, the major of the 200 students belonged to the health science track, and that of the 200 students didn't. After a self-administered survey was conducted, the answer sheets from 319 respondents were analyzed. As a result, there appeared no differences between the health-related majors and the health-unrelated majors in body dysmorphic disorder. Although there might be various factors to concern body dysmorphic disorder, both groups found themselves to suffer from more depression when they had a severer body dysmorphic disorder, and their body dysmorphic disorder exerted a statistically significant influence on their self-rated depression. Therefore the careful management of body dysmorphic disorder was required, and it's especially needed to make research in that of health-related majors. At the same time, more detailed clinical research efforts should be directed into body dysmorphic disorder and self-rated depression.

• The Journal of the Korea Contents Association
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• v.16 no.2
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• pp.25-44
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• 2016

This research aims to examine how military executive members and local residents mutually perceive the military family support. The 217 individuals from the military executive and the 191 local residents took part in this research. The results of this study are as follows: First of all, in the sense of the agreement, the respondents from the military executive had higher perception when it comes to the necessity of the community support, whilst the answer from their counterparts did not. Second of all, in terms of the congruence(1) on this issue, the perception levels that the each group of respondents showed are not corresponded, besides each group had different level of demands on the community resources according to the analysis of the congruence(2). Third, regarding the accuracy(1), the military executive members called for higher coverage of community supports whilst the local residents perceived that the executive members might be having less demands. The accuracy(2) too shows the different perception on the resources that the each group has. Last of all, for the meta-agreement, which indicates how each group found its counterpart's perception, were only corresponded at the lower level.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9879-9884
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• 2014

Aim: The purpose of the current study was to conduct a systematic review of the published literature to evaluate the diagnostic accuracy of FDG-PET, PTE/CT, MRI and scintigraphy for multiple myeloma related bone disease. Methods: Through a search of PubMed, EMBASE, and the Cochrane Library, two reviewers independently assessed the methodological quality of each study. We estimated pooled sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR), and two sample Z-tests were conducted to evaluate for differences in sensitivity, specificity, area under the curve (AUC), and the $Q^*$ index between any two diagnostic modalities. Results: A total of 17 studies were reviewed. The MRI had a pooled sensitivity of 0.88, specificity of 0.68, AUC of 0.897, and $Q^*$ index of 0.828, whereas for MIBI, the corresponding values were 0.98, 0.90, 0.991, and 0.962, respectively, and for bone scan, they were 066, 0.83, 0.805, and 0.740, respectively. The corresponding values of MIBI were 0.98, 0.90, 0.991, and 0.962, respectively. For PET and PET/CT, the values were 0.91, 0.69, 0.927 and 0.861, respectively. Statistically significant differences were not found in the sensitivity, specificity, AUC, and $Q^*$ index between MRI, scintigraphy, FDG-PET and PET/CT. Conclusions: On the condition that X ray is taken as a reference in our study, we suggested that FDG-PET, PTE/CT, MRI and scintigraphy are all associated with high detection rate of bone disease in patients with MM. Thus, in clinical practice, it is recommended that we could choose these tests according to the condition of the patient.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.4787-4793
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• 2014

Background: Many cancer patients experience poor pain control due to various factors, including misconceptions regarding the use of opioid analgesics. For management of cancer pain, interventions involving education of both patients and physicians have been attempted. Objectives: This review aimed to assess the current evidence of the benefits of education for the management of cancer pain. Methods: We searched the Medline, EMBASE, Cochrane library, and major Korean databases to identify relevant studies. We included most study designs, but excluded case series. The primary outcomes were pain intensity and quality of life (QoL). Two reviewers assessed the risk of bias using the Cochrane's tool for RCT and Risk of Bias Assessment tool for Non-randomized Studies (RoBANS) for non-randomized studies, independently. Results: After extensive searches, 3,324 publications were screened, and 32 studies were selected. The education interventions used in the included studies included a wide variety of education methods, but the most common method was a booklet produced for patients. Regardless of the education method used, the results of the meta-analysis were as follows. The SMDs of the most severe, average, and current pain in the RCTs were significant. The SMD of worst, average, and current pain were -0.34 (-0.55, -0.13), -0.40 (-0.64, -0.15), and -0.79 (-1.35, -0.23). In the non-randomized studies, the effects on average pain were significant, but those on worst and current pain were not. Conclusions: Education intervention reduced the pain of cancer patients. Therefore, patient education could be considered to be an effective method of cancer pain management. However, our data should be interpreted with caution, and studies using standardized protocols are needed to confirm these observations.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.499-512
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• 2014

Architecture is usually seen as a product of art and technology. However, most historical buildings also exemplify various sophisticated principles of mathematics. Outstanding examples of architecture around the world such as Seokguram, Daewoongjun of Bulguksa, Muryangsujeon of Buseoksa, and the Parthenon provide students with a great opportunity to study their underlying mathematical properties and principles. The activity of identifying and investigating such mathematical principles in historical buildings enables students to realize that mathematics is a practical subject, and thus provides justification for the study and importance of mathematics. For the purpose of this study historical architecture was reviewed with this in mind in order to develop STEAM education materials focused on elementary school mathematics. The result of this study is as follows: first of all, appropriate examples of historical architecture were selected on the basis of the 2009 revised curriculum's content and teaching goals. These involved chapters on 'proportion', 'symmetry', 'movement of figures', 'building blocks', and 'triangles'. Secondly, a meta-analysis was performed on the historical buildings that clearly illustrate mathematical principles. Thirdly, STEAM education materials focused on elementary mathematics using architectural examples were developed which made actual application in classrooms possible. And lastly, surveys of professional groups were conducted to verify whether the produced materials were suitable teaching resources.