• Archives of Pharmacal Research
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• v.19 no.4
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• pp.264-268
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• 1996

Panax-ginseng saponin has been known to exert various pharmacological effects on cellular metabolism. This study was performed to determine the effect of ginseng saponin on gap junction channel-mediated intercellular communication, using an established in vitro system of reconstituted gap junction channels. Gap junction channels are a specialized plasma membrane fraction, which are permeable to relatively large water-soluble molecules. The sucrose permeable property of reconstituted gap junction channels was completely inhibited with 0.1 % (w/v) of ginseng saponin. We also compared the effect of ginseng saponin with that of Triton X-100, a nonionic detergent, on the same system. Triton X-100 showed significantly different effect on sucrose-permeability of gap junction channel from that was affected by ginseng saponin. The structures of liposomes containing gap junction channels was significantly destroyed by Triton X-100.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.5
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• pp.1310-1317
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• 2015

Two-phase flow boiling heat transfer in micro-channels was experimently investigated. The test section consisted of 15 rectangular micro-channels with a depth of 0.45mm, width of 0.20mm. The experiments were performed for heat fluxes ranging from 5.6 to 46.1kW/m2 and mass fluxes from 150 to 450kg/m2s using FC-72 as the working fluid. According to the results, at the low heat flux region, heat transfer coefficient strongly depends on the heat flux, while heat transfer coefficient at the high heat flux region was independent on the heat flux. Four correlations were used to predict the heat transfer coefficient. The measured heat transfer coefficient was compared with four correlations. It was found that Kaew-On and Wongwises's correlation well predicted the measured data, within the MAE of 40.3%.

• Journal of Communications and Networks
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• v.9 no.1
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• pp.11-17
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• 2007

In this paper, system performance of turbo trellis coded modulation (turbo TCM) is presented and analyzed through computer simulations over two typical channels, namely additive white Gaussian noise (AWGN) and Rayleigh fading channels. We use and compare different mapping strategies based on Ungerboeck partitioning (UP), block partitioning (BP), mixed partitioning (MP), Gray partitioning (GP), and Ungerboeck-Gray partitioning (UGP) of the signal constellation of the turbo TCM system. Furthermore, taking 8PSK modulation of turbo TCM as an example, our simulation results show that turbo TCM with UP can obtain better performance than turbo TCM with BP, MP, GP, and UGP in both AWGN and Rayleigh fading channels.

• Journal of Communications and Networks
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• v.11 no.5
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• pp.473-479
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• 2009

Conventional frequency domain equalization (FDE) schemes were originally devised for quasi-static channels. Thus, such equalization schemes could suffer from significant performance degradation in fast-fading channels. This paper proposes a frequency domain equalization algorithm to mitigate the effect of fast time-varying fading. First, a mathematical expression is derived to quantify the total interference resulting from the time variation of the channel. Then, the proposed approach attempts to eliminate the effect of time-variations of the channel. This cancellation allows efficient use of the classical FDE structures in fast time-varying fading environments, although they are built upon the quasi-static channel model. Simulation results of bit-error-rate performance are provided to demonstrate the effectiveness of the proposed algorithm.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.301-304
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• 2006

This paper presents a review of the important recent literature available in the area of micro-channel flow analysis and mixing. The topics covered include the physics of flows in micro-channels and integrated simulation of micro-channel flows. Also the flow control models and electro-kinetically driven micro-channel flows are explained. A comparison of various mixing principles in micro-channels are provided in sufficient detail.

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.38-38
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• 2002

Whole-cell recordings from adult rat sympathetic neurons demonstrate that calcium current is comprised of at least three types, N, L '||'&'||' R. We are using cell-attached patch recording to identify the single calcium channels that underlie these macroscopic currents. Single channels were resolved the presence of 100 mM Ba$\^$2＋/ and l${\mu}$M BayK 8644 over the voltage range -40 to $\^$＋/50 mV.(omitted)

• Journal of the Optical Society of Korea
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• v.8 no.4
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• pp.149-155
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• 2004

Newly developed modal transmission-line theory(MTLT) is used to analyze rigorously the optical power distribution in grating-assisted directional couplers(GADCs) with three guiding channels. By defining a novel coupling efficiency ${\eta}$ amenable to the rigorous analytical solutions of modal transmission-line theory, we explicitly evaluate the power coupling and distribution of TM modes. The results reveal that the incident power is sensitively partitioned through three output channels in terms of such grating parameters as the grating period, the duty cycle, and the operating wavelength.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.6
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• pp.1085-1091
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• 2002

Chang Chung-ching(張仲景) in the Later Han(Eastern Han) Dynasty of Chinese history wrote the treatise on Diseases Caused by Cold Factors(傷寒論; Shang Han Lun) on the basis of the fundamental theory of Emperor's Classic of Internal Medicine(黃帝內經; ECIM) after collecting medical treatment experiences until the Han Dynasty. It had great significance that Shang Han Lun was the origin of treating six-channels(六經) and there showed the peculiar guidelines on the diagnosis and treatment of oriental medicine to divide diseases into six-channels. The oriental medical doctors who had studied Shang Han Run thought highly of meridians and until now it was generally known that the chapter of heat in the Plain Questions of ECIM(黃帝內經, 素問ㆍ熱論) was the basis of Shang Han Run. The chapter of heat in the Plain Questions of ECIM was the first text in which the basic theory on six-channels according to the types of illness was introduced. In my point of view, the theory of treating six-channels had close relation to the Chapter of Channels in Miraculous Pivot of ECIM(黃帝內經, 靈樞ㆍ經脈篇) as well as the chapter of heat in the Plain Questions of ECIM. Therefore I took a look at the origin of treating six-channels in Shang Han Lun and illuminated again the meaning to compare the parts of in Shang Han Lun with the Chapter of Channels in Miraculous Pivot of ECIM. Conclusion: The, symptoms divided into six-channels in the chapter of channels in ECIM gave the fundamental basis of diagnosis and treatment basesd on overall analysis of signs and symptoms(辨證論治) an illness in the Zangfu(臟腑) in respect of meridians. Viewed in the light of diagnosis and treatment basesd on overall analysis of signs and symptoms(辨證論治), the symptoms of YangMing-channel(陽明經) in the Chapter of Channels in Miraculous Pivot of ECIM were, for the most part, accord with those of YangMing-disease in Shang Han Lun. Furthermore, the symptoms in Shang Han Lun were explained definitely and in detail. Therefore the theory of Shang Han Lun has been developed on the basis of ECIM with the changes of the times. YangMing-disease in Shang Han Lun implied medical cases in stomach meridian(胃經) and large intestine meridian(大腸經). Therefore Shang Han Lun was the foundation of treatment basesd on overall analysis of signs and symptoms(辨證論治) in respect of meridian as well as the text in which the steps of infectious diseases(外感病) of human bodies were explained.

• Journal of Mechanical Science and Technology
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• v.17 no.3
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• pp.429-439
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• 2003

Counter-current two-phase flows of air- water in narrow rectangular channels with offset strip fins have been experimentally investigated in a 760 mm long and 100 mm wide test section with 3.0 and 5.0 mm gap widths. The two-phase flow regime, channel-average void fractions and two-phase pressure gradients were studied. Flow regime transition occurred at lower superficial velocities of air than in the channels without fins. In the bubbly and slug flow regimes, elongated bubbles rose along the subchannel formed by fins without lateral movement. The critical void fraction for the bubbly-to-slug transition was about 0.14 for the 3 mm gap channel and 0.2 for the 5 mm gap channel. respectively. Channel-average void fractions in the channels with fins were almost the same as those in the channels without fins. Void fractions increased as the gap width increased, especially at high superficial velocity of air. The presence of fins enhanced the two-phase distribution parameter significantly in the slug flow, where the effect of gap width was almost negligible. Superficial velocity of air dominated the two-phase pressure gradients. Liquid superficial velocity and channel gap width has only a minor effect on the pressure gradients.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.2
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• pp.583-599
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• 2015

We apply the Bayesian matching pursuit (BMP) algorithm to the estimation of time-frequency selective channels in orthogonal frequency division multiplexing (OFDM) systems. By exploiting prior statistics and sparse characteristics of propagation channels, the Bayesian method provides a more accurate and efficient detection of the channel status information (CSI) than do conventional sparse channel estimation methods that are based on compressive sensing (CS) technologies. Using a reasonable approximation of the system model and a skillfully designed pilot arrangement, the proposed estimation scheme is able to address the Doppler-induced inter-carrier interference (ICI) with a relatively low complexity. Moreover, to further reduce the computational cost of the channel estimation, we make some modifications to the BMP algorithm. The modified algorithm can make good use of the group-sparse structure of doubly selective channels and thus reconstruct the CSI more efficiently than does the original BMP algorithm, which treats the sparse signals in the conventional manner and ignores the specific structure of their sparsity patterns. Numerical results demonstrate that the proposed Bayesian estimation has a good performance over rapidly time-varying channels.