• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.55 no.2
• /
• pp.52-61
• /
• 2006

For the detection of moving objects, background subtraction methods are widely used. An adaptive Gaussian mixture model combined with probabilistic learning is one of the most popular methods for the real-time update of the complex and dynamic background. However, probabilistic learning approach does not work well in high traffic regions. In this paper, we Propose a reliable learning method of complex and dynamic backgrounds in high traffic regions.

• Journal of Microbiology
• /
• v.40 no.2
• /
• pp.173-177
• /
• 2002

In order to identify Yawowia lipolytica genes induced by serum, cDNA representational difference analysis was performed using a PCR-select CDNA subtraction method. One of the genes cloned from the subtraction was a gene (YIMBFl) homologous to Saccharomyces cerevisiae MBF1 encoding the coactivator multiprotein bridging factor 1. Disruption of YIMBFl revealed that the gene was net essential for viability, and the Ylmbf△ strain did not show any distinct phenotypic change on solid serum medium. In liquid medium, however. a difference was found in the ability to maintain hyphae induced by serum. This result suggests that the YIMbf1 protein may mediate transcriptional activation of certain genes involved in the hypha fonmation of Y. lipolytica.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.10
• /
• pp.4092-4107
• /
• 2015

We propose a background subtraction method for moving cameras based on trajectory classification, image segmentation and label inference. In the trajectory classification process, PCA-based outlier detection strategy is used to remove the outliers in the foreground trajectories. Combining optical flow trajectory with watershed algorithm, we propose a trajectory-controlled watershed segmentation algorithm which effectively improves the edge-preserving performance and prevents the over-smooth problem. Finally, label inference based on Markov Random field is conducted for labeling the unlabeled pixels. Experimental results on the motionseg database demonstrate the promising performance of the proposed approach compared with other competing methods.

• Journal of Magnetics
• /
• v.9 no.3
• /
• pp.69-74
• /
• 2004

A method of processing signals of unaligned geomagnetic sensors placed on the seabed is presented. The offset drifts of the fluxgate sensors are processed by polynomial fitting and the orientations of the sensor axes are found by minimizing the noise power using wavelet analysis. The noise power was reduced by 9.1 dB by processing the components of magnetic field separately using subtraction filter, polynomial fitting and wavelet analysis.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.10a
• /
• pp.738-741
• /
• 2009

This research is concerned for improving the result of speech recognition under the noisy speech. We knew that spectral subtraction and recovery of valleys in spectral envelope obtained from noisy speech are more effective for the improvement of the recognition. In this research, the averaged spectral envelope obtained from vowel spectrums are used for the emphasis of valleys. The vocalic spectral information at lower frequency range is emphasized and the spectrum obtained from consonants is not changed. In simulation, the emphasis coefficients are varied on cepstral domain. This method is used for the recognition of noisy digits and is improved.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.10
• /
• pp.138-142
• /
• 2016

Dual-energy digital radiography (DEDR) has been used for detecting lesions within the body using energy subtraction methods. The purpose of this study was to acquire optimal bone and tissue image by changing physical factors such as Tube voltage (kVp) and add filters, and then we compared with the predicted values using SRS-78 program and experimental results. For that purpose, we acquired images according to changes in physical parameters of various materials since we had to acquire the optimal bone and tissue image using energy subtraction. Used phantom consists of aluminum and polymethyl methacrylate (PMMA) and a comparison of image optimization was measured by contrast-to-noise ratio (CNR). In results, first of all, we confirmed that a subtraction image from 50 kVp image and 120 kVp image is optimal bone and tissue image. Also when we added a 10 mm Aluminum add filter, we expected it is a result of the optimal bone and tissue image. Besides, we confirmed these results are consistent with the predicted optimized condition by SRS-78 program.. In conclusion, we indicated that we can acquire optimal bone and tissue image by controling physical factors such as kVp, add filters through this study. Also we expected that DEDR will contribute to the field of medical imaging technology.

• Journal of Elementary Mathematics Education in Korea
• /
• v.13 no.2
• /
• pp.285-304
• /
• 2009

The operations of fractions are the main contents of number and operations in the elementary mathematics curriculum. They are also difficult for students to understand conceptually. Nevertheless, there has been little study on the addition and subtraction of fractions. Given this, this paper explored the connection between the national mathematics curriculum and its concomitant textbooks, the adequacy of when to teach, and the method of constructing each unit to teach addition and subtraction of fractions. This paper then analyzed elementary mathematics textbooks and workbooks by three parts aligned with the general instructional flow: 'introduction', 'activity', and, 'exercise'. First, it was analyzed with regard to the introduction part whether the word problems of textbooks might reflect on students' daily lives as intended, how different meanings of operations would be expected to be taught, and how the subsequent activities were connected with the original word problems. Second, the main analysis of activity part of the textbooks dealt with how to use concrete or iconic models to promote students' conceptual understanding of operations and how to formalize the calculation methods and principles with regard to addition and subtraction of fractions. Third, the analysis of the part of exercise in the textbooks and workbooks was conducted with regard to problem types and meanings of operations. It is expected that the issues and suggestions stemming from this analysis of current textbooks and workbooks are informative in developing new instructional materials aligned to the recently revised mathematics curriculum.

• School Mathematics
• /
• v.18 no.3
• /
• pp.625-645
• /
• 2016

This study clarified the big ideas related to teaching addition and subtraction of fractions with different denominators based on quantitative reasoning with unit and recursive partitioning. An analysis of this study urged us to re-consider the content related to the addition and subtraction of fraction. As such, this study analyzed textbooks and teachers' manuals developed from the fourth national mathematics curriculum to the most recent 2009 curriculum. In addition and subtraction of fractions with different denominators, it must be emphasized the followings: three-levels unit structure, fixed whole unit, necessity of common measure and recursive partitioning. An analysis of this study showed that textbooks and teachers' manuals dealt with the fact of maintaining a fixed whole unit only as being implicit. The textbooks described the reason why we need to create a common denominator in connection with the addition of similar fractions. The textbooks displayed a common denominator numerically rather than using a recursive partitioning method. Given this, it is difficult for students to connect the models and algorithms. Building on these results, this study is expected to suggest specific implications which may be taken into account in developing new instructional materials in process.

• Proceedings of the IEEK Conference
• /
• 1999.11a
• /
• pp.267-270
• /
• 1999

In this paper, a new method to reduce the size of ROM in the direct digital frequency synthesizer (DDFS) is proposed. In the case that ROM is used for sinusoidal value calculation, reducing the size of ROM is significant. So the power consumption is affected mostly by its bit width. In the proposed method, the ROM bit width is reduced by 1 bit using the phase subtraction and the approximation. The spurious level is better than 80㏈c and the power consumption estimated is 510㎼/MHz.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.37 no.4
• /
• pp.251-256
• /
• 1988

This work describes a speech analysis of Korean number ('1'-'10') which are spoken by several speakers using Fast Walsh Transform(FWHT) method. FWHT includes only addition and subtraction operations, therefore faster and needs less memory than FFT(Fast Fourier Transfifrm) or LPC(Linear Predictive Coding) analysis method. We have investigated that FWHT method can find speaker independent feature(which represents same cue about some word independent of different speakers) The results of this experiment, the 70% of same words(korean number '2')which spoken by several speakers have had slmilar patterns.