• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.1
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• pp.108-125
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• 2015

We propose a new time-division half-duplex estimate-and-forward (EF) relaying strategy suitable for a relay with mobility. We reconfigure EF relaying to guarantee a strong relay-destination link which is required to achieve a high rate using EF relaying. Based on the reconfigured model, we optimize the relaying strategy to attain a high rate irrespective of the relay position with preserving the total transmit bandwidth and energy. The proposed relaying strategy achieves high communication reliability for any relay position, which differs from conventional EF and decode-and-forward (DF) relaying schemes.

• Journal of information and communication convergence engineering
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• v.7 no.3
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• pp.304-308
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• 2009

This paper proposes a new concept of a signal constellation of the recently introduced half-symbol-rate-carrier phase-shift keying (HSRC-PSK) modulations for bandwidth-efficient high speed data communications. Since the HSRC-PSK modulations contain different symbol energies representing the same bit sequences due to the loss of orthogonality of their HSRC signals, it is very hard to represent the symbol using the conventional signal constellation. To resolve the problem, two different energies are assigned to represent one symbol for the HSRC offset quadrature phase shift keying (OQPSK) modulation. Similarly, the different energies exist to display the different symbol for HSRC minimum shift keying (MSK) modulation. With the proposed signal space representation, HSRC-PSK symbol can easily be shown with a two-dimensional scatter plot which provides helpful information of evaluating HSRC-PSK signal's quality.

• International Journal of Vascular Biomedical Engineering
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• v.1 no.2
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• pp.13-19
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• 2003

Endothelial release of nitric oxide (NO) contributes to the regulation of vascular tone by inducing vascular relaxation. To estimate the blood flow-dependent nitric oxide level and half-life (T1/2) of nitric oxide in vivo state, we investigated the change of aortic NO currents during the change of aortic blood flow rate using NO-selective electrode system and electromagnetic flowmeter in the aorta of anesthetized rats. Resting mean aortic blood flow rate was $49.6{\pm}5.6ml/min$ in the anesthetized rats. NO currents in the aorta were increased by the elevation of blood pressure and/or blood flow rate. When the aortic blood flow was occluded by the clamping, aortic NO currents were decreased. The difference of NO concentration between resting state and occluded state was $1.34{\pm}0.26{\mu}M$ (n=7). This NO concentration was estimated as blood flow-dependent nitric oxide concentration in the rats. Also, while the aortic blood flow was occluded, NO currents were decreased with exponential pattern with $12.84{\pm}2.15$ seconds of time constant and $7.70{\pm}1.07$ seconds of half-life. To summarize, this study suggested that blood flow-dependent NO concentration and half-life of nitric oxide were about $1.3{\mu}M$ and 7.7 seconds, respectively, in the aorta of anesthetized rats. The nitric oxide-selective electrode system is useful for the direct and continuous measurement of NO in vivo state.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.491-499
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• 2003

The Okinawa Trough is a rift basin formed by extension. Analysis of multichannel seismic reflection profiles from the northwestern margin of the northern Okinawa Trough reveal that the trough is characterized by a series of tilted fault blocks bounded by listric normal faults and half-grabens developed between blocks, showing typical rifted structures. The trough display three kinds of sedimentary sequences with different seismic reflection characteristics: prerift, synrift and postrift sediments. The prerift sequence develops parallel to the dip direction of tilted fault blocks. The synrift sediments, mostly deposited in the half-grabens between tilted fault blocks, are generally well characterized by divergence of the reflectors towards the blocks indicating contemporaneous deposition during tilting. The postrift sediments are featured by continuous and parallel reflectors. The width of the half-graben and the throw-displacement rate of the basin bounding fault are closely connected. The throw-displacement rate is the maximum when the rifting event is the most active and the width of the half-graben is proportional to the rate.

• The Journal of the Acoustical Society of Korea
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• v.15 no.6
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• pp.59-65
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• 1996

This paper proposes a 4 kbps PSI-VSELP(Pitch Synchronous Innovation-Vector Sum Excited Linear Prediction) speech coder which produces speech equivalent to that of the conventional 4.8 kbps VSELP. Since the 'half-rate' is differently defined from country to country, there may be a need to reduce the bit rate of conventional half-rate coder. To minimize the degradation of speech quality caused by bit-rate reduction, it is desirable to perform bit-allocation based on the carefull consideration of the effect of various transmission parameters. This paper adopts this analytical approach for bit-allocation at 4 kbps. To improve the quality of the VSELP coder at 4 kbps, basis vectors which play the most important role in the performance, are optimized by an iterative closed-loop training process and the PSI technique is employed in the VSELP performance, are optimized by an iterative closed-loop training process and the PSI technique is employed in the VSELP coder. To demonstrate the performance of the proposed speech coder, we peformed experiments under the noiseless and error free conditions. From experimental results, even though the proposed 4 kbps PSI-VSELP coder showed lower scores in the objective measure, higher scores in subjective measure was obtained compared with those of the conventional 4.8 kbps VSELp.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.339-342
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• 2004

It is research about special quality of ozone gas concentration and dissolved ozone concentration that show according to change of flow rate when liquefied ozone gas in water. If increase flow rate of ozone gas, ozone concentration increases being proportional and amount to fixed flow rate, dissolved ozone concentration was measured low. When ozone concentration How rate 1000 [ppm], dissolved ozone concentration smelted to flow rate 1.5[Q] for 28 [min] is $0.1740{\sim}0.8020[mg/l]$. Could know that half-life is most short by 3 minutes 8 seconds in flow rate 1.5 [Q]. And ozone smelted 20 minutes later after half-life measurement became disjointing all.

• Journal of IKEEE
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• v.23 no.4
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• pp.1218-1223
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• 2019

In HVDC systems, the full-bridge submodule increases the number of components compared to the half-bridge submodule, but the failure-rate can be reduced by securing 100 % redundancy. However, full-bridge submodules require more complex control algorithms to ensure the redundancy and to prevent arm-short with sufficient dead-time. To solve this problem, we analyse the failure-rate of the paralleled half-bridge configuration with the same number of components and 100 % redundancy as the full-bridge submodule. The fault tree analysis (FTA) method is applied to the conventional part failure analysis to reflect the operation risk of the submodule, thereby predicting the life-cycle of the submodule more accurately. To verify the validity, the failure-rate results of the proposed FTA based analysis method are compared with the failure rate obtained by the part failure method.

• JSTS:Journal of Semiconductor Technology and Science
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• v.4 no.4
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• pp.275-279
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• 2004

A new burst mode clock and data recovery circuit is realized that improves the previousldy-known gated-oscilletor technique with half rate clock recovery, The circuit was fabricated with 0.25um CMOS technology, and its functions were confirmed up to 1 Gbps.

• Journal of the Korean Society of Costume
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• v.40
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• pp.95-107
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• 1998

The purpose of this research paper is to offer basic data for cloth design which is intended to apply appropriate shape and catacity to cloth. Followings are the analyzed result of investigation which was conducted to figure out the character of middle aged from 35 to 59 years old-women body especially in lower half of their body. 177 women took part in this investigation. 1. As a result of analyzed characters for middle aged women body shape, taking a side view of body, there are great variance in thickness coefficient which indicates the size of body. 2. According to a comparison result of early middle aged women body shape with late middle aged women body shape, the value in height items get shorter otherwise the value in thickness items get longer getting older. It means late middle aged women are relatively fat. 3. For the analysis of women body especially in lower half, 8 factors were used. They are as followings. Factor 1. Side thickness of lower half. Factor 2. Width of lower half. Factor 3. Height of lower half Factor 4. Droop of underbelly Factor 5. Salient rate of buttocks. Factor 6. Length of buttocks. Factor 7. Salient rate of underbelly. Factor 8. Droop of buttocks 4. Lower half shapes of middle aged women were divided into three groups and the character of each group are as followings. 〈Group 1〉65.0% of women who took part in this investigation have this type of body shape. They have long value in height items and thickness items. 〈Group 2〉16.4% of women who take part in this investigation were belonged to this group. The value in height items were not so different from group 1 but the thickness value are shorter than group 1. Women of group 2 have slime body shape. 〈Group 3〉18.6% of women were belonged to group 3. They show the shortest value in height items otherwise the longest value in thickness items. Therefore they are the smallest and the fattest group in this investigation.

• Korean Journal of Clinical Pharmacy
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• v.1 no.1
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• pp.31-36
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• 1991

Tobramycin is one of the most frequently selected agents for pharmacokinetic drug monitoring because of its narrow therapeutic index and essential role for the management of serious infections, especially gram-negative infections. Its pharmacokinetic parameters are dependent on race, sex, age, ideal body weight. disease states, and etc. Therefore, to schedule the dosing of tobramycin, the individual pharmacokinetic parameters such as half-life and volume of distribution are needed. However, these pharmacokinetic parameters have never been reported in Koreans. The purposes of this study were to evaluate the volume of distribution of tobramycin in cancer patients who had normal renal function, to compare the mean values of Vd reported in the literature, and to compare the measured half-life with the expected half-life based on ABW, LBW, and IBW, respectively. Venous blood samples were collected just before and thirty minutes after dosing during steady state. Serum tobramycin concentrations were determined by $TD_x$ (fluorescence immunoassay). IBW were measured by the method of Devine: and LBW were measured by the method of Hallynck. Creatinine clearances (CLcr) of the patients were estimated using the Cockcroft and Gault equation. Elimination rate constants (kel) were determined using the Welling and Craig equation. Infusion rate (ko), volume of distribution (Vd), and half-life $(t_{1/2})$ were determined using the Saw chuk and Zaske equation. The volume of distribution Was $27\%$ greater than the Schentag's study (0.26 vs 0.33 l/kg), but the half-life was similar to the Levy's study. The predicted half-lives based on IBW were the closest to actual half-lives (1.85 vs 2.01 hr).