• East Asian mathematical journal
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• 제40권2호
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• pp.183-207
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• 2024

This study is a case study that considered fractional senses and fraction operation abilities for 107 gifted students in elementary school classes. In order to find out the fractional sense, in the first question comparing the sizes of fractions 2/3 and 4/5, the students showed a variety of strategies, but the utilization rate of strategies excluding reduction to a common denominator did not exceed 50%. The second question can be solved by using the first question. It is a problem of finding two fractions by selecting four from six numbers 1, 3, 4, 5, 6, and 7 to create two fractions of which sum does not exceed 1. The percentage of correct answers to this question was about 27% (29 out of 107). Only 5 out of 29 students found answers using the first question, and the rest of the students sought answers through trial and error in various calculations. It shows that the item arrangement method from a deductive perspective has no significant effect on elementary school students. The percentage of correct answers was about 27% in the questions to find out the fraction operation ability-the question of drawing a 4/3 bar using a given 3/8-sized bar and 30.7% (23 out of 75) of the students who had wrong answers showed insufficient splitting operation. In addition, it has been shown that the operation of partitioning and iterating to form numerical senses and fractional concepts related to the fractions of the students has no significant impact.

• Asian Pacific Journal of Cancer Prevention
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• 제15권9호
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• pp.4071-4077
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• 2014

Background: The effects of CYP1A1 gene polymorphisms on the risk of bladder cancer (BC) remain controversial. We carried out a meta-analysis to clarify the role of CYP1A1 gene polymorphisms in BC. Material and Methods: A comprehensive literature search was conducted up to November 20, 2013. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the strength of the association. Meta-regression, subgroup analysis, sensitivity analysis and publication bias were also performed. Results: Eight studies involving 1,059 BC cases and 1,061 controls were included. The meta-analysis showed that there was no significant association between the two common mutations of CYP1A1 and BC risk. For the I1e462Val A/G polymorphism with GG vs. AA the OR was 1.47 (95 % CI= 0.70-3.07, P =0.308). For the MspI T/C polymorphism, though a slight trend was found this was not statistically nonsignificant (CC vs.TT, OR = 1.24, 95 % CI= 0.98-1.58, P =0.078). Subgroup analyses by ethnicity also found no obvious association between CYP1A1 and BC risk. Conclusion: The present meta-analysis suggests that CYP1A1 polymorphism is not associated with bladder cancer risk.

• 상하수도학회지
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• 제19권4호
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• pp.487-496
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• 2005

Chlorine bulk decay tests were carried out by bottle test under controlled conditions in a laboratory. Experiments were performed at different temperatures: $5^{\circ}C$, $15^{\circ}C$, $25^{\circ}C$, and the water temperatures when samples were taken from the effluent just before entering to its distribution system. 38 bulk tests were performed for water of Al (water treatment plant), 4 bulk tests for A2 (large service reservoir), and A3(pumping station). Residual chlorine concentrations in the amber bottles were measured over time till about 100 hours and bulk decay coefficients were evaluated by assuming first-order, parallel first-order, second-order. and $n^{th}-order$ reaction. The $n^{th}-order$ coefficients were obtained using Fourth-order Runge-Kutta Method. A good-fit by the average coefficient of determination ($R^2$) was first-order ($R^2=0.90$) < parallel first-order ($R^2{_{fast}}=0.92$, $R^2{_{slow}}=0.95$) < second-order ($R^2=0.95$) < $n^{th}-order$ ($R^2=0.99$). But if fast reaction of parallel first-order bulk decay were applied to the effluent of large service reservoir with ca. 20 hours of travel time and slow reaction in the water distribution system following the first 20 hours, parallel first-order bulk decay would be best and easy for application of water quality modeling technique.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.959-962
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• 2013

Objective: HBV infection may cause damage to the immune system and induce lymphomas as a result. Some scholars have indicated that HBsAg(+) reflecting HBV infection may have a relationship with lymphoma development. This study was designed to find out the specific stage of HBV infection which may be related to lymphoma. Methods: HBV serum markers, including HBsAg, HBsAb, HBeAg, HBeAb, HBcAb were tested among 100 lymphoma patients and 100 other patients who were diagnosed with non-lymphoma diseases in the First Hospital of Jilin University from 2010.1.1 to 2012.12.31. Three subgroups were established depending on different combinations of HBV serum markers. Subgroup 1 was HBsAg(+) representing the early stage of HBV infection. Subgroup 2 was HbsAb(+) representing convalescence and Subgroup 3 was "HbsAg and HbsAb negative combined with other positive markers" representing the intermediate stage of HBV infection. Chi square tests were used to compare the rates of three subgroups in lymphoma and control groups. Results: The rates of Subgroup were 13% and 5% respectively, an association between HBsAg and lymphoma being found (P<0.05). There was no difference between rate of Subgroup 2 of lymphoma group (15%) and that of control group (16%). In lymphoma group and control group, the rate of Subgroup 3 was different (12% vs 4%). This evidence was not specific to T cell lymphoma, B cell lymphoma or Hodgkin's lymphoma. Conclusions: Among serum markers of HBV, the combination of serum markers representing the early stage and intermediate stage of HBV infection have a relationship with lymphoma. Convalescence from HBV infection appears to have no relationship with lymphoma.

• 음성과학
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• 제12권2호
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• pp.101-108
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• 2005

Apraxia of phonation (AOP) has often been described as a feature of apraxia of speech or of severe non-fluent type of aphasia. Pure AOP is rare and, to our knowledge, only two cases have been reported. Brain lesion sites of the reported cases were not those sites known to be responsible for apraxia of speech. This study presents a case of AOP which resulted from the secondary stroke in the left corona radiata immediately following the first stroke in the left temporoparietal lobe. A 61-year old right-handed man shwoed a global type of aphasia after the first cerebral infarction, but was able to generate spontaneously some short fragments of speech. On the day after the first infarction, he suffered from the secondary infarction, leaving him a complete loss of voluntary phonation. He did not showed any significant change in language functions. Several occurrences of involuntary phonation were observed upon laughing or crying. He was also able to cough unintentionally. A vidoe-stroboscopic examination failed to reveal any evidence of structural and functional impairment in larynx. Although this case is not of pure form of AOP, AOP appeared after the secondary stroke without significant changes of language impairment since the first stroke. Therefore, AOP may be a consequence of the brain lesion from the secondary stroke even though we cannot rule out the possibility of an additive effect of the secondary to the first stroke.

• 대한지구과학교육학회지
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• 제6권2호
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• pp.112-123
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• 2013

Under this research, the survey is made on the definitive influence of the first-year education process of the science focus school for each of humanities, science and science core courses and the level of satisfaction of the non-curriculum experiment activity program for each course to find out the effectiveness of the first-year education process of the science focus school. For this purpose, this research has set three research issues. First, By clarifying the research result through the first-year education curriculum for science core school, noticeable change was observed for science focus school students through the change of attitude related to science for each desired course of students. Second, in the self-directed learning characteristics change, there was meaningful change for each desired field of students. Students hoping for humanities curriculum had great help in improvement of creative thinking for openness, creativeness and the like, but the influence was slightly insufficient in the moderation and control capability on themselves in learning attitude. Third, By analyzing the research result comprehensively, the first-year education curriculum for science core school provides high level of tailored science learning for the science focus school students and the level of satisfaction for students was significantly high.

• 한국CDE학회논문집
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• 제22권1호
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• pp.37-43
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• 2017

3D printing techniques can be used in various application fields and many researches have been reported. FDM (Fused Deposition modeling) can make multi-material or multi-color models with the simultaneous use of two or more filaments. In a dual-nozzle FDM printers, while the active nozzle is working, the remaining nozzle will be idle. The remaining molten resins inside an idle nozzle can ooze out unwantedly. The spill over from the resting nozzle produces unwanted remaining on the fabricated product. In this research, we suggest a method for optimizing building position of a model to minimize the unwanted spill-over that could possibly contaminate the final product. The method is based on minimizing the two intersection volumes. The first intersection volume is obtained by intersecting the volume defined by the first material and the Minkowski sum between the volume of the first material and the vector obtained by subtracting the center point of the first nozzle from the center point of the second nozzle. The second intersection volume can be obtained by reversing the role of the first and second volumes and nozzles. Some results obtained from the implementation using the Parasolid (Siemens) geometric modeling kernel is presented.

• 한국물환경학회지
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• 제27권3호
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• pp.300-305
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• 2011

This study aimed at analyzing the runoff quality by the layer thickness and material of soil roof to make best use of the rainwater falling on it in terms of safety and efficiency and resulted in the following assessments. It turned out that the concentrations decreased more in T-N, $NO_3$-N, $NH_4$-N, T-P and $PO_4$-P in roof rainwater except 30 cm for the RW1 soil roof after passing through it than those of first rainwater. On the other hand, the concentrations in rainwater passing through gravel roof turned out to be equal or same to those of the first rainwater. As a result of analysis of metallic stuff in runoff, there was no indication of Cd, Cr, Mn and Pb as well. The concentration of Cu, Fe and Zn in rainwater through soil roof became less than that of the first rainwater. In this research, the soil roof showed the good efficiency in lowering the concentration of such components as nitrogen, phosphorus and metals. Based on the results from this work, more practical study would be required further in the future in relation to soil roof when installing the rainwater-utilizing facilities.

• 대한가정학회지
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• 제8권1호
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• pp.124-145
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• 1970

The author carried out this study to research the biological value of the protein fermented wheat bran. This study mainly devided into two parts. First part includes seven subgroups composed of five rats and second part fourteen subgroups composed of six rats each. In the first part of this study forty weanling male rats, aged 40${\pm}$5 days were fed by fermented wheat bran diet for seven weeks. In second part of this study 90 male weanling rats were fed by rice and soybean diet supplemented by fermented wheat bran. In the first part of this study food consumption rate of fermented group showed higher than standard group but the former group is lower than the later in the body weight gains. In the second part of this study, rice groups showed same trend of the result of the first part, but soybean groups did not go along with the result of rice group. In regard to body nitrogen retention rate, fermented wheat diet group showed higher than the standard group in the first part of this study. In the second part of this study rice diet groups revealed same result as that of the first part of this study but soybean diet did not give the same result in this respect. There was no significant difference in organ weight in all experimental groups but devided by 100 gram of body weight, the reverse is true in compare with body weight gains. Hematological investigation did not show the significance in both experimental and standard groups of the first and the second studies. It is conclusion of this study that rice which is inferior to soybean in protein quality, increases the rate of supplementary effect by fermented wheat bran in all respects of this study.

• 한국신뢰성학회지:신뢰성응용연구
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• 제11권3호
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• pp.213-224
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• 2011

In this paper, we analyze statistically the data set of first leak time of water pipeline. We classify first the leak time data by pipe type, location, diameter of pipe and, length of pipe. We perform the analysis of variance to indicate that there are significant difference of mean of the time between levels of the factor and also compare the distribution of levels using the multiple box-plot. When there are the difference of the mean, we perform the least significant test to find out what levels of the facor has a different mean.