• Journal of Biomedical Engineering Research
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• v.14 no.2
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• pp.163-167
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• 1993

We developed a ventricular assist device(VAD) to be used as a bridge to heart transplantation or a circulatory assist device for patients with end-stage heart disease or poor myocardial function after cardiac surgery. It is a pneumatic and diaphragm-type VAD and its stroke volume is 90 cc. The upper housing and diaphragm is made of a segmented polyurethane and the lower back plate is made of a polycarbonate. Two Carbomedics$^R$ mechanical valves are used as inlet and outlet valves. It was tested in vitro and the cardiac output of the VAD was 7 L/min at a heart rate of 70 bpm. The line pressure from a pressure transducer inserted in the pneumatic line was recorded and compared with the ideal pressure tracing.

• The Journal of the Acoustical Society of Korea
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• v.26 no.5
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• pp.194-198
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• 2007

In this paper, we apply a discriminative weight training to a statistical model-based voice activity detection(VAD). In our approach, the VAD decision rule is expressed as the geometric mean of optimally weighted likelihood ratios(LRs) based on a minimum classification error(MCE) method which is different from the previous works in that different weights are assigned to each frequency bin which is considered more realistic. According to the experimental results, the proposed approach is found to be effective for the statistical model-based VAD using the LR test.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.282-291
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• 1995

We investigated HBV markers in serum and cerebrospinal fluid of 50 subjects with neurologic disorders or other disorders, who visited Dept. of neurology, college of medicine, Yeungnam University, from April-1 to August-31 1994 and were performed cerebrospinal fluid analysis to investigate the detection rate of HBV markers in cerebrospinal fluid and the possibility of neurologic disorders associated with HBV infection. The results were as follows. The positivity of HBsAg and HBV prevalence rate in serum were 6(12.0%) and 37(74.0%). The number of patient with HBsAg, only anti-HBV and no markers were 6(12.0%), 31(62.0%) and 13(26.0%), respectively. The positivity of HBsAg and HBV prevalence rate in cerebrospinal fluid were 3(6%) and 18(36.0%). The number of patient with HBsAg, only anti-HBV and no markers were 6(100.0%), 12(38.7%) and 0(0.0%) respectively. The number of patient with virus associated diseases(VAD) and non virus associated diseases(NVAD) were 26(52%) and 24(48%). The HBV prevalence rate in serum of VAD and NVAD groups were 88.5% and 58.3% (p<0.05). The HBV prevalence rate in CSF of VAD and NVAD groups were 53.8% and 16.7%(P<0.05). The HBV prevalence rate in serum and CSF of VAD and NVAD groups were 60.9% and 28.6%. Aa a conclusion, the HBV markers in the CSF were partially detected at the presence of the HBV markers in serum. The prevalance rate of HBV in the CSF was increased at the HBsAg positive in the serum and the serum and the CSF was significantly increased at the VAD group than the NVAD group.

• Proceedings of the IEEK Conference
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• 2000.06d
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• pp.98-101
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• 2000

On CELP type Vocoders G.723.1 6.3kbps/5.3kbps Dual Rate Speech Codec, which is developed for Internet Phone and videoconferencing, uses VAD(Voice Activity Detection)/CNG (Comfort Noise Generator) in order to reduce the bit rate in a silence period. In order to reduce the bit rate effectively in this paper, we first set the boundary condition of the energy threshold to prevent the consumption of unnecessary processing time, and use three decision rules to detect an active frame by energy, pitch gain and LSP distance. To evaluate the performance of the proposed algorithm we use silence-inserted speech data with 0, 5, 10, 20dB of SNR. As a result when SNR is over 5dB, the bit rate is reduced up to about 40% without speech degradation and the processing time is additionally decreased.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.6 no.1
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• pp.23-28
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• 2013

In this paper, background noise reduction method using dual microphone is proposed in mobile environment. Each Signal, reference and primary, would be replaced by microphone input signals, which were measured by reference and primary microphones, and then, noise reduction was performed using FDAF. After then, residual and background noise would be estimated and reduced by MMSE-LSA. For consistent noise reduction performance, result of VAD that could be caculated by PLD between two microphones was used.

• Journal of Korea Multimedia Society
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• v.17 no.3
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• pp.294-299
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• 2014

In this paper, we propose a novel algorithm to improve the performance of a voice activity detection(VAD) which is based on the generalized normal-Laplace(GNL) distribution. In our algorithm, the probability density function(PDF) of the noisy speech signal is represented by the GNL distribution and the variance of the speech and noise of GNL distribution are estimated using higher order moments. Experimental results show that the proposed algorithm yields better results compared to the conventional VAD algorithms.

• Journal of Korean Neurosurgical Society
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• v.44 no.3
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• pp.109-115
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• 2008

When a tear occurs in one of the major cervicocerebral arteries and allows blood to enter the wall of the artery and split its layers, the result is either stenosis or aneurysmal dilatation of the vessel. Vertebral artery dissection (VAD) is an infrequent occurrence but is a leading cause of stroke in young and otherwise healthy patients. This article discusses recent developments in understanding of the epidemiology and pathogenesis of VAD and the various clinical manifestations, methods of diagnosis, and approaches to treatment.

• 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.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.158.2-158.2
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• 2003

Vitamin K-related analogs induce growth inhibition in various cancer cell lines. We report that 2,3-dichloro-5,8-dihydroxy-1, 4-naphthoquinone (DDN), a naphthoquinone analog, induces mitochondria-dependent apoptosis in human promyeloid leukemic HL-60 cells. DDN induced cytochrome c release, cleavage of Bid, and activation of caspases -8, -9 and -3. Cleavage of Bid, the caspase-8 substrate, was inhibited by the broad caspase inhibitor zVAD-fmk, whereas cytochrome c release was not affected by zVAD-fmk. (omitted)

• 순환기질환의공학회:학술대회논문집
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• 2001.11a
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• pp.41-42
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• 2001