• Title/Summary/Keyword: proportional expression

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Analysis on Elementary Students' Proportional Thinking : A Case Study with Two 6-graders (초등학교 6학년 학생의 비례 추론 능력 분석 : 2명의 사례 연구)

  • Ko, Eun-Sung;Lee, Kyung-Hwa
    • Journal of Educational Research in Mathematics
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    • v.17 no.4
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    • pp.359-380
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    • 2007
  • This study was conducted with two 6-graders to identify how were their proportional reasoning abilities, whether they evolved proportional thinking in a various context, and what had influence on their proportional thinking. The findings, as previous researches noted, suggested that the proportional expression obtaining by instrumental understanding could not provide rich opportunities for students to improve understanding about ratio and proportion and proportional reasoning abilities, while being useful for determining the answers. The students were able to solve proportional problems with incorporating their knowledge of divisor, multiples, and fraction into proportional situations, but not the lack of number sense. The students easily solved proportional problems experienced in math and other subjects but they did not notice proposition in problems with unfamiliar contexts.

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A Study on the Relationship between Architecture and polyphony music - Focusing on Proportional Characteristic of Space - (건축과 다성음악의 상관성에 관한 연구 - 공간의 비례적 특성을 중심으로 -)

  • IRhim, Sung-Sup;Lee, Ho-Joung
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2004.11a
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    • pp.122-127
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    • 2004
  • This study is about a relationship of architecture and polyphony music. In the field of interior architecture, there have been many tries of applying characteristics of music, such as abstraction and nature of time for users of space to have new experience. It has been possible because architecture and music have similarities in many ways. Regarding using proportional characteristic in architecture and music, the both fields are enormously related in some ways. The purpose of this study is explaining of possibility of architectural expression in music and suggesting a way of analysing architectural design based on musical elements emphasizing proportional characteristic. Therefore, it is going to analyse Counterpoint of Bach, which is well expressed in music and compare it with proportional characteristic of space through this study.

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A study on the Sixth Graders' Solving Proportional problems in the 7th curriculum Mathematics Textbooks (초등학교 6학년의 교과서 비례 문제 해결에 관한 연구)

  • Kwon, Mi-Suk;Kim, Nam-Gyun
    • Education of Primary School Mathematics
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    • v.12 no.2
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    • pp.117-132
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    • 2009
  • The purpose of this study was analysis on types of strategies and errors when the sixth grade students were solving proportion problems of mathematics textbooks. For this study, proportion problems in mathematics textbooks were investigated and 17 representative problems were chosen. The 277 students of two elementary schools solved the problems. The types of strategies and errors in solving proportion problems were analyzed. The result of this study were as follows; The percentage of correct answers is high if the problems could be solved by proportional expression and the expression is in constant rate. But the percentage of correct answers is low, if the problems were expressed with non-constant rate.

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Comparison of the Curricula and the Textbooks Concerning the Proportion and Ratio Area between Korea and Singapore (비와 비율 영역에 대한 우리나라와 싱가포르 교육과정 및 교과서 비교 -TIMSS 평가목표와 공개문항을 중심으로)

  • Kim, Kyung-Hee;Paik, Hee-Su
    • School Mathematics
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    • v.12 no.4
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    • pp.473-491
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    • 2010
  • In the TIMSS assessment goal and open TIMSS 2007, Singapore recorded a lower overall achievement level compared with Korea; however, the excellent results shown by Singapore furnished an opportunity for various countries to research into the education in Singapore. This paper conducted a comparative analysis of the "Proportion, Proportional Expression, and Percentile" area out of the three topics involving "Fractions and Decimals", "Proportion, Proportional expression, and Percentile", and "Measurement", in all of which Singapore exhibited a higher percentage of correct answers than Korea. The paper was able to discover the following differences through a comparative analysis of how Korean and Singaporean textbooks deal with the open questions of TIMSS 2007 after looking into them according to four assessment goals. First, the Singaporean textbook introduced the concept of proportion one year ahead of the Korean textbook. Second, the Singaporean textbook repeatedly coped with the topic of "Proportion, Proportional Expression, and Percentile" in depth and by academic year, and its volume was larger than that of the Korean textbook. Third, there was a difference in the introduction and definition of the concept of proportion. Fourth, the way of introducing a proportional expression was also different, and the Singaporean textbook proposed many more questions that utilize this expression in ordinary life. Based on these differences, the paper suggested implications that could be applied to the Korean curriculum and textbook.

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Speed Characteristics of Direct Current Shunt Motors (직류 분권전동기의 속도 특성)

  • Shin, Myoung-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.3
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    • pp.69-72
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    • 2012
  • It is well known that speed of a direct current shunt motor is inverse proportional to flux. This paper presents speed expression to show that speed is not inverse proportional to flux. The presented speed vs. flux curves are verified by experimental result that shows the need of the revision of speed vs. flux curves shown in conventional text books.

Aberrant Expression of CCAT1 Regulated by c-Myc Predicts the Prognosis of Hepatocellular Carcinoma

  • Zhu, Hua-Qiang;Zhou, Xu;Chang, Hong;Li, Hong-Guang;Liu, Fang-Feng;Ma, Chao-Qun;Lu, Jun
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.13
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    • pp.5181-5185
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    • 2015
  • Background: CCAT1 has been reported to be linked with pathogenesis of malignancies including colon cancer and gastric cancer. However, the regulatory effect of CCAT1 in hepatocellular carcinoma (HCC) remains unclear. The purpose of this research was to identify any role of CCAT1 in the progression of HCC. Materials and Methods: Real time-PCR was performed to test the relative expression of CCAT1 in HCC tissues. A computation screen of CCAT1 promoter was conducted to search for transcription-factor-binding sites. The association of c-Myc with CCAT1 promoter in vivo was tested by Pearson correlation analysis and chromatin immunoprecipitation assay. Additionally, Kaplan-Meier analysis and Cox proportional hazards analyses were performed. Results: c-Myc directly binds to the E-box element in the promoter region of CCAT, and when ectopically expressed increases promoter activity and expression of CCAT1. Moreover, Kaplan-Meier analysis demonstrated that the patients with low expression of CCAT1 demonstrated better overall and relapse-free survival compared with the high expression group. Cox proportional hazards analyses showed that CCAT1 expression was an independent prognostic factor for HCC patients. Conclusions: The findings demonstrated CCAT1, acting as a potential biomarker in predicting the prognosis of HCC, is regulated by c-Myc.

A Study on the Polyphony Music Proportion which Appears Today in the Architecture Space (현대 건축 공간에 나타난 다성음악적 비례에 관한 연구)

  • Rhim Sung-Sup;Lee Ho-Joung
    • Korean Institute of Interior Design Journal
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    • v.14 no.2 s.49
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    • pp.46-54
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    • 2005
  • This study is about the polyphony music proportion which appears today in the Architecture space. In the field of interior architecture, there have been many tries of applying characteristics of music, such as abstraction and nature of time for users of space to have new experience. It has been possible because architecture and music have similarities in many ways. Regarding using proportional characteristic in architecture and music, the both fields are enormously related in some ways. The purpose of this study is explaining of possibility of architectural expression in music and suggesting a way of analysing architectural design based on musical elements emphasizing proportional characteristic. Therefore, it is going to analyse Counterpoint of Bach, which is well expressed in music and compare it with proportional characteristic of space through this study.

Performance Analysis of Proportional Fair Scheduling with Partial Feedback Information for Multiuser MIMO-OFDMA Systems (다중 사용자 MIMO-OFDMA 시스템에서 부분 궤환 정보를 이용한 비례적 공정 스케줄링의 성능 분석)

  • Kang, Min-Gyu;Byun, Il-Mu;Park, Jin-Bae;Kim, Kwang-Soon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.6A
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    • pp.643-651
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    • 2008
  • In this paper, we analyze the performance of normalized SNR based proportional fair scheduling with partial feedback information for multiuser MIMO-OFDMA systems. The closed form expression on the downlink capacity of the selective partial CQI feedback scheme is derived and its asymptotic behavior is investigated. From the performance analysis and numerical results, it is found that the optimal growth rate of downlink capacity can be achieved with bounded average feedback overhead irrespective of the number of users.

MACC1 Expression Correlates with PFKFB2 and Survival in Hepatocellular Carcinoma

  • Ji, Dong;Lu, Zhong-Tang;Li, Yao-Qing;Liang, Zhe-Yong;Zhang, Peng-Fei;Li, Chao;Zhang, Jun-Li;Zheng, Xin;Yao, Ying-Min
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.2
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    • pp.999-1003
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    • 2014
  • Objective: To validate the relationship between MACC1 and 6-phosphofructo-2-kinase/fructose 2, 6 bisphosphatase (PFKFB2) expression as well as its clinicopathological features and prognostic significance in hepatocellular carcinoma. Methods: By using immunohistochemistry, we investigated the MACC1 and PFKFB2 protein expression in 60 pairs of hepatocellular carcinoma and corresponding non-tumor tissues. Using the Mann-Whitney U test, the Chi-square test, Kaplan-Meier survival analysis, Cox proportional hazard regression analysis and Spearman analysis, we studied the relationship between MACC1 and PFKFB2 protein expression and postoperative overall survival (OS) of the HCC patients. Results: MACC1 and PFKFB2 positive staining rates were significantly higher in hepatocellular carcinoma than in the corresponding nontumor tissues (P=0.012 and 0.04, respectively). The clinicopathological features evaluation revealed that positive expression of MACC1 was associated with a high Edmondson classification (P=0.007) and advanced TNM stage (P=0.027). Similar findings were evident for PFKFB2 expression (P=0.002 and P=0.027). MACC1 and PFKFB2 positive expression was associated with a lower OS rate (P=0.004 and 0.03, respectively). Kaplan-Meier survival and Cox proportional hazard regression analyses revealed MACC1 positive expression to be a prognostic factor for postoperative OS, but PFKFB was not. Conclusion: Highly expressed MACC1 and PFKFB2 protein were associated with TNM stage, Edmondson-Steier classification and overall survival. MACC1 may affect tumor metabolism partly through expression and phophorylation of PFKFB2.

Multiuser Heterogeneous-SNR MIMO Systems

  • Jo, Han-Shin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.8
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    • pp.2607-2625
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    • 2014
  • Previous studies on multiuser multiple-input multiple-output (MIMO) mostly assume a homogeneous signal-to-noise ratio (SNR), where each user has the same average SNR. However, real networks are more likely to feature heterogeneous SNRs (a random-valued average SNR). Motivated by this fact, we analyze a multiuser MIMO downlink with a zero-forcing (ZF) receiver in a heterogeneous SNR environment. A transmitter with Mantennas constructs M orthonormal beams and performs the SNR-based proportional fairness (S-PF) scheduling where data are transmitted to users each with the highest ratio of the SNR to the average SNR per beam. We develop a new analytical expression for the sum throughput of the multiuser MIMO system. Furthermore, simply modifying the expression provides the sum throughput for important special cases such as homogeneous SNR, max-rate scheduling, or high SNR. From the analysis, we obtain new insights (lemmas): i) S-PF scheduling maximizes the sum throughput in the homogeneous SNR and ii) under high SNR and a large number of users, S-PF scheduling yields the same multiuser diversity for both heterogeneous SNRs and homogeneous SNRs. Numerical simulation shows the interesting result that the sum throughput is not always proportional to M for a small number of users.