• The Journal of the Acoustical Society of Korea
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• v.30 no.6
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• pp.324-329
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• 2011

In this paper, we propose a novel approach to improve the performance of a statistical model-based voice activity detection (VAD) which is based on the conditional maximum a posteriori (CMAP) with deviation. In our approach, the VAD decision rule is expressed as the geometric mean of likelihood ratios (LRs) based on adapted threshold according to the speech presence probability conditioned on both the speech activity decisions and spectral deviation in the pervious frame. Experimental results show that the proposed approach yields better results compared to the CMAP-based VAD using the LR test.

• Journal of Science Education
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• v.37 no.2
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• pp.338-347
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• 2013

The purposes of this study were to develop the activity based STEAM education program and to investigate the effects of the developed program on students' interest in science learning. The program was applied to 7th grade science club. This study was planned to single group pre-post test design. Test tool was the questionnaire of interest on science learning. In the results of t-test, there was statistically significant difference on the pretest and posttest of interest in science learning. Also there was significant difference on attitude toward science, recognition and strategy on science learning that were subdomains of interest on science learning. The results indicated that activity-based STEAM education program was effective in improving students' interest in science learning. In future, studies should be conducted that examine the effect of STEAM program on creativity and problem-solving activity. Therefore studies on the effectiveness of activity-based STEAM education programs should be made continuously.

• School Mathematics
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• v.2 no.2
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• pp.475-487
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• 2000

As a result of carrying out t-test against the learning activity that used the learning materials designed by level, significant disparity was found. Thus, it was found that hte effect of this learning activity became more visible with lapse of time. But the major cause by which there appeared small significant disparity as a result of testing is that the units of experiment were limited and that the period of using the learning materials was not long. In an analysis on the results of interest test, the experimental class also appeared to show the average score that was higher than that of the comparative class by 0.10 after converting a decimal point. The outcome of attitude test was that the experimental class showed a higher average score by 0.11, as a result of converting a decimal point, than that of the comparative class. So, a large number of students showed an improved reaction. But, there seemed some problems of the learning materials or the method of progressing the activity in changing under achievement students or students who avoided studying math. When the effect of the level-based learning activity was investigated, more than 80% of the experimental class’s students showed a positive reaction. Thus, it could be judged that students, who felt some burden at studying math, might be served more largely, not by teacher’s uniform instruction, but by an individual learning using the level-based learning materials that enabled them to do a systematic self-learning for themselves.

• Archives of Pharmacal Research
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• v.29 no.6
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• pp.459-463
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• 2006

Previous studies on the anticonvulsant activity of $N-Cbz-{\alpha}-aminoglutarmides$ have shown that the derivatives of $N-Cbz-{\alpha}-amino-N-alkoxy$ glutarimide have significant anticonvulsant activity. In addition, their anticonvulsant activities are dependent on the presence of N-alkoxy groups. Based on these results, a series of $N-Cbz-{\alpha}-amino-glutarimidooxy$ carboxylates derivatives (3a-e) were synthesized in moderate yield using a known synthetic procedure. Their anticonvulsant activities were evaluated using the maximal electroshock seizure (MES) test, the pentylene tetrazole induced seizure (PTZ) test, and the strychinine (Str) threshold test with the ultimate aim of developing more active anticonvulsants. None of the compounds (3a-e) tested showed anticonvulsant activity in the MES and PTZ test. However, all the compounds tested exhibited significant anticonvulsant activity in the Str. test. The most active compound in the Str. test was the methyl ester of $N-Cbz-{\alpha}-amino-glutarimidooxy$ acetic acid 3a $(ED_{50}\;=\;42.9\;mg/kg)$.

• Journal of Families and Better Life
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• v.30 no.6
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• pp.115-127
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• 2012

This study's aim was to analyze the effect of a project activity based on role play on 5-year-olds' mathematical ability. The participants of this study were 56 5-year-olds from two educational institutions for young children located in two metropolitan cities in Korea. The experimental group (n=28) participated in a project activity based on role play, while the comparative group (n=28) did not. The "Mart Play" project activity based on role play was developed emergently by the children and teachers of the experimental group. The children's mathematical ability was measured before and after the experiment. The data were analyzed using t-test and ANCOVA. As a result, the project activity based on role play had an effect on the improvement of 5-year-olds' mathematical ability generally, but not on their measurement ability.

• ETRI Journal
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• v.34 no.2
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• pp.184-189
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• 2012

In this paper, we propose a novel approach to statistical model-based voice activity detection (VAD) that incorporates a second-order conditional maximum a posteriori (CMAP) criterion. As a technical improvement for the first-order CMAP criterion in [1], we consider both the current observation and the voice activity decision in the previous two frames to take full consideration of the interframe correlation of voice activity. This is clearly different from the previous approach [1] in that we employ the voice activity decisions in the second-order (previous two frames) CMAP, which has quadruple thresholds with an additional degree of freedom, rather than the first-order (previous single frame). Also, a soft-decision scheme is incorporated, resulting in time-varying thresholds for further performance improvement. Experimental results show that the proposed algorithm outperforms the conventional CMAP-based VAD technique under various experimental conditions.

• Korea Journal of Hospital Management
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• v.20 no.3
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• pp.36-44
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• 2015

The Activity Based Costing(ABC) means the process that makes clear how the actions and input resources have changed into service to calculate medical services costs. These days, the number of hospital which is using the ABC system is increasing to make their policy decision making efficient and run the hospitals more resonable. This study analyzes the unbalance in the level of health insurance service fee and the improvement plans based from 8 hospitals(ABC system) and 95 clinics(ABC survey). The cost recovery ratio has shown different levels according to each service type. A surgery service type recorded 76.8% and an evaluation & management service type is 84.6%, a treatment procedure type(85.8%), a function test type(91.6%) and health insurance fee even did not reach to the original cost. Meanwhile, a laboratory test type and imaging test type show high level of cost recovery ratio. they recorded 188.3% and 158.8%. Resultingly now of unbalance in the level of health insurance service fee accelerates supply of every test. so there is a need to make laboratory test type and imaging test type lower to keep balance with the surgery and medical service. These methods should be performed gradually with monitoring the unbalance fee ratio and for this, a panel medical institution have to be established for generalizations of studying result, fairness of selecting researching sample.

• The Journal of the Acoustical Society of Korea
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• v.27 no.7
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• pp.372-378
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• 2008

Voice activity detectors (VAD) are important in wireless communication and speech signal processing, In the conventional VAD methods, an expression for the likelihood ratio test (LRT) based on statistical models is derived in discrete Fourier transform (DFT) domain, Then, speech or noise is decided by comparing the value of the expression with a threshold, This paper presents a new statistical VAD method based on a signal subspace approach, The probabilistic principal component analysis (PPCA) is employed to obtain a signal subspace model that incorporates probabilistic model of noisy signal to the signal subspace method, The proposed approach provides a novel decision rule based on LRT in the signal subspace domain, Experimental results show that the proposed signal subspace model based VAD method outperforms those based on the widely used Gaussian distribution in DFT domain.

• Journal of Applied Biological Chemistry
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• v.49 no.3
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• pp.90-94
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• 2006

Bactericidal activity of grapefruit seed extract (GSE)-based disinfectant, as a safe disinfectant, was measured against five bacteria by Korean Food & Drug Administration (KFDA) dilution-neutralization method. GSE-based disinfectant showed a 99.9999% bactericidal activity against Escherichia coli ATCC 10536, Salmonella typhi ATCC 29629, Staphylococcus aureus ATCC 6538, Bacillus cereus ATCC 11778, and Listeria monocytogenes ATCC 1911 at the concentration of 2.15% GSE. It showed better bactericidal activity against Gram-negative bacteria of E. coli ATCC 10536 and S. typhi ATCC 29629 at lower concentration of GSE (0.43%). Based on the results, it was suggested that a possible bactericidal mechanism of GSE active ingredients was due to the abrupt osmotic shift during the bactericidal activity test by KFDA method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.3
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• pp.633-652
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• 2024

Software testing is an important phase as it ensures the software quality. The software testing process comprises of three steps: generation, execution, and evaluation of test cases. Literature claims the usage of single and multiple 'Unified Modeling Language' (UML) diagrams to generate test cases. Using multiple UML diagrams increases test case coverage. However, the existing approaches show limitations in test case generation from UML diagrams. Therefore, in this research study, we propose an approach to generate the test cases using UML State Chart Diagram (SCD), Activity Diagram (AD), and Sequence Diagram (SD). The proposed approach transforms UML diagrams into intermediate forms: SCD Graph, AD Graph, and SD Graph respectively. Furthermore, by integrating these three graphs, a System Testing Graph (STG) is formed. Finally, test cases are identified from STG by using a traversal algorithm such as Depth First Search (DFS) that is an optimization method. The results show that the proposed approach is better compared to existing approaches in terms of coverage and performance. Moreover, the generated test cases have the ability to detect faults at the unit level, integration, and system level testing.