• Ocean and Polar Research
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• v.30 no.3
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• pp.303-312
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• 2008

Despite the impacts of the climate changes on the pelagic ecosystem, few studies have examined the pelagic-benthic coupling in the adjacent East China Sea and Korea Strait. Therefore, the species composition and abundance of the macrobenthic community, as well as the potential food sources of benthic fauna were investigated in the present study using stable isotope analysis (${\delta}^{13}C\;and\;{\delta}^{15}N$) for suspended particulate organic matter (SPOM), sedimentary organic matter (SOM), phytoplankton, and zooplankton. A total of 157 macrobenthic fauna were collected, and the density of the macrobenthic fauna ranged from 4 to 434 ind./0.25 $m^2$, with an average density of 149 ind./0.25 $m^2$. The density of the benthic fauna increased moving from offshore shelf sites to coastal sites adjacent to the Korea Strait. Cluster analysis showed that the macrobenthic communities consisted of three distinct groups: group A in the Korea Strait, group B in the East China Sea, and group C near Ieodo. The dominant species in group A were the amphipods Photis japonica and Ampelisca miharaensis, followed by the polychaete Scolotoma longifolia. Environmental variables, such as the temperature of the seawater and sediment, and oxygen, and chlorophyll a levels, appeared to affect the structure of the community, suggesting the importance of coupling with the pelagic system. The ${\delta}^{13}C$ values of SPOM and zooplankton ranged from -22.97 to -23.5% and -19.92 to -21.86%, respectively, showing a relatively narrow range(<1%) between the two components. The difference between the ${\delta}^{13}C$ values of SOM and pelagic organic matter was also within 1%, suggesting that the SOM originated from the pelagic system, which is an important factor controlling the macrobenthic community.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9A
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• pp.710-716
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• 2003

OFDM is a very attractive technique for achieving high-bit-rate data transmission and high spectrum efficiency. However one of disadvantages of OFDM signal is the high PAPR characteristic when multicarriers are added up coherently. In this paper, we propose an adaptive PTS scheme using two threshold levels for PAPR reduction and reducing the amount of PAPR calculations with clipping scheme. Simulation results show that it is almost same between average bit error rate performance of the proposed scheme and that of a conventional scheme. Also, we obtain a great performance gain in the amount of calculations compared to the conventional scheme. Therefore, proposed system has a good performance in data processing time in OFDM wireless communication systems.

• Journal of Korea Multimedia Society
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• v.23 no.2
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• pp.204-215
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• 2020

People who have sleep disorders such as insomnia take a long time to get to sleep, namely sleep latency. In order to reduce it, effective stimulations and environments to induce sleep such as ASMR or pink noise are necessary. However these have different effects and preferences for each individual. Therefore customized service and control for the sleep induction will be provide to him/her. In this paper, we proposed SIS control system which provides selectively sound control among various kinds of ASMR and pink noise according to sleep state measured from brain wave data for an individual. In order to verify the effectiveness of the system, we had conducted totally 30 experiments for 5 people, and all EEG data measured from all the people during sleep. An average of 3.7 hours was spent per experiment. In comparison experiments with and without sound control for sleep induction, the latency time was reduced by an average of 8 minutes as well as delta waves and theta waves, which appear only in deep sleep, are increased by 21%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.1
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• pp.24-29
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• 2002

In this paper, the microstructure and the dielectric properties of Sr$\_$1-x/CaxTiO$_3$(0$\leq$x$\leq$0.2)-based grain boundary layer ceramics were investigated. The sintering temperature and time were 1420∼152 0$\^{C}$ and 4 hours in N$_2$ gas, respectively. The average grain size and the lattice constant were decreased with increasing content of Ca, but the average grain size was increased with increase of sintering temperature. The second phase foamed by the thermal diffusion of CuO from the surface leads to verb high apparent dielectric constant, $\xi$$\_$r/>50000 and low dielectric loss, tan$\delta$<0.05. X-ray diffraction patterns of Sr$\_$1-x/CaxTiO$_3$ exhibited cubic structure, and the peaks shifted upward and the peak intensity were decreased with x. This is due to the lattice contraction as Sr is replaced by Ca with a smaller ionic radius. The specimens treated thermal diffusion for 2hrs in 1150$\^{C}$ exhibited nonlinear current-voltage characteristic, and its nonlinear coefficient(a) was overt 7.

• Journal of Multimedia Information System
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• v.8 no.3
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• pp.147-158
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• 2021

Versatile Video Coding (VVC) is the latest video coding standard developed by Joint Video Exploration Team (JVET). In VVC, the quadtree plus multi-type tree (QT+MTT) structure of coding unit (CU) partition is adopted, and its computational complexity is considerably high due to the brute-force search for recursive rate-distortion (RD) optimization. In this paper, we aim to reduce the time complexity of inter-picture prediction mode since the inter prediction accounts for a large portion of the total encoding time. The problem can be defined as classifying the split mode of each CU. To classify the split mode effectively, a novel convolutional neural network (CNN) called multi-level tree (MLT-CNN) architecture is introduced. For boosting classification performance, we utilize additional information including inter-picture information while training the CNN. The overall algorithm including the MLT-CNN inference process is implemented on VVC Test Model (VTM) 11.0. The CUs of size 128×128 can be the inputs of the CNN. The sequences are encoded at the random access (RA) configuration with five QP values {22, 27, 32, 37, 42}. The experimental results show that the proposed algorithm can reduce the computational complexity by 11.53% on average, and 26.14% for the maximum with an average 1.01% of the increase in Bjøntegaard delta bit rate (BDBR). Especially, the proposed method shows higher performance on the sequences of the A and B classes, reducing 9.81%~26.14% of encoding time with 0.95%~3.28% of the BDBR increase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.269-277
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• 2003

Effects of soy protein concentrate (SPC) containing isoflavone and casein diets on plasma phospholipid (PLs)-fatty acid patterns were investigated in 7-& 40- wk old female rats. Diets containing 16% SPC (soy/young:SY, soy/old: SO) and casein (casein/young : CY, casein/ old: CO) supplemented with 0.5% cholesterol were fed for 4 wks. Fatty acid compositions of plasma PLs were determined by TLC and GLC. Compared to the dietary protein effects, age effects on serum lipids were more profound. The levels of total cholesterol (Chol.), triglyceride, HDL-Chol., (LDL+VLDL)-Chol. and atherogenic index (AI) were higher in older groups (OC & OS) than younger groups (YC &. YS). Soy groups had higher Ell)L-Chol. level and lower (LDL+ VLDL)-Chol. and AI, compared with casein groups. The compositions of C22:0, Cl8:1 $\omega$9 and sum of MUFA in plasma PLs were significantly higher in casein group (CY & CO) than soy group (SY & SO), but those of sum of SFA were higher in soy group. The compositions of C22:0, Cl8:1 $\omega$9, C22:1, Cl8:3$\omega$3 and C22:4$\omega$6 were higher and those of C22:6$\omega$3, sum of $\omega$3, Cl8: 2$\omega$6 C20:4$\omega$6, sum of $\omega$6 and sum of PUFA were lower in plasma PLs of younger rats. The average P/S and $\omega$3/$\omega$6 ratio in older group was higher. The $\Delta$-7 desaturation index (16:0⇒16:1$\omega$7) and $\Delta$-9 desaturation index (18:0⇒18:1$\omega$9) were lower in soy group than casein group, while $\Delta$-6 and $\Delta$-5 desaturation index were not affected by dietary protein. The $\Delta$-4 desaturation index (22:4$\omega$6⇒22:5$\omega$6) were higher and elongation index (20:4$\omega$6⇒22:4$\omega$6) were lower in older group. The ratio of the products of $\omega$3 fatty acid series (Cl8:3) was significantly higher in older group, which indicated that age affected the plasma PUFA metabolism. On the other hand, older rats had higher serum cholesterol level compared with younger rats. Taken together, these changes in fatty acid composition might cause minimal changes in tile membrane fluidity induced by the increase serum cholesterol level.

• Journal of the Optical Society of Korea
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• v.10 no.3
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• pp.99-104
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• 2006

We introduce a novel contrast mechanism for imaging superparamagnetic iron oxide (SPIO) nanoparticles (average diameter ${\sim}100nm$) using magneto-motive optical Doppler tomography (MM-ODT), which combines an externally applied temporally oscillating high-strength magnetic field with ODT to detect the nanoparticles flowing through a glass capillary tube. A solenoid cone-shaped ferrite core extensively increased the magnetic field strength ($B_{max}=1\;T,\;{\Delta}|B|^2=220T^2/m$) at the tip of the core and also focused the magnetic force on targeted samples. Nanoparticle contrast was demonstrated in a capillary tube filled with the SPIO solution by imaging the Doppler frequency shift which was observed independent of the flow rate and direction. Results suggest that MM-ODT may be a promising technique to enhance SPIO nanoparticle contrast for imaging fluid flow.

• ETRI Journal
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• v.31 no.5
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• pp.610-612
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• 2009

We present intra-mixture prediction (IMP) mode for intra prediction and an enhanced estimation method for most probable mode (MPM). IMP mode supports more flexibility in intra prediction by mixing $4{\times}4$ blocks and $8{\times}8$ blocks in one macroblock, while the enhanced MPM estimation extends the number of referenced neighboring blocks and efficiently uses their prediction modes depending on their positions. Simulation results show that the combination of both proposed methods provides a bit reduction in the Bj${\phi}$ntegaard delta bitrate by an average of 2.56% compared to H.264/AVC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.1
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• pp.5-12
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• 1991

the Chinese cabbage kimchi was fermented with the various submaterials such as hot pep-per garlic ginger leek green onion fermented anchovy juice and sugar according to the average contents of each submaterial described in the 39 kinds of references. And then the effects of each submaterial and lactic acid bacteria such as L. brevis. Leu. mesenteroides. P cerevisiae and L. plantarum on the content of carotenes were investigated, The major carotene in kimchi was $\beta$-carotene. And also $\delta$-carotene and $\alpha$-carotene were detected. Contents of $\beta$-carotene and total carotene were high in the kimchi containing leek red pepper powder green onion and fermented anchovy juice as a submaterial. But the kimchi containing or omitting the other submaterials were litter affected to the contents of carotene. Contents of $\beta$-carotene and total carotene were high in kimchi fermented with Leu. msenteroides L. brevis and P. cerevi-siae as a starter but was low with L plasntarum.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.5
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• pp.42-46
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• 1999

The strengthening of a metal matrix composite(MMC) by the shape memory effect(SME) of dispersed TiNi particles was theoretically studied. An analytical model was constructed for the prediction of the average residual stress(<$\delta$>m) on the base of the Eshelby's equivalent inclusion method. The analysis was performed on the TiNi particle/Al metal matrix composites with varying volume fractions and prestrains of the particle. The residual stress caused by the shape memory of predeformed fillers has been predicted to contribute significantly to the strengthening of this composite.