• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.5B
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• pp.475-488
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• 2003

To prevent performance degradation of TCP due to packet losses in the smooth handoff by the route optimization extension of Mobile IP protocol, a buffering of packets at a base station is needed. A buffering of packets at a base station recovers those packets dropped during handoff by forwarding buffered packets at the old base station to the mobile user. But, when the mobile user moves to a congested base station in a new foreign subnetwork, those buffered packets forwarded by the old base station are dropped and TCP transmission performance of a mobile user in the congested base station degrades due to increased congestion by those forwarded burst packets. In this paper, considering the general case that a mobile user moves to a congested base station, we analyze the influence of packet buffering on TCP performance according to handoff arrival distribution for Drop-tail and RED (Random Early Detection) buffer management schemes. Simulation results show that RED scheme can reduce the congestion increased by those forwarded burst packets comparing Drop-Tail, but RED scheme cannot avoid Global Synchronization due to forwarded burst packets by the old base station and new buffer management scheme to avoid it is needed in Mobile IP based networks.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.2
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• pp.215-222
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• 1997

Ten rice varieties were planted at two locations (lowland and highland), during the wet and dry seasons of different years. In vivo digestibility and voluntary intake of the straw, were determined in groups of fat-tail sheep, supplemented with $18g{\cdot}kg^{-0.75}$ concentrate DM, containing ~20% crude protein. Voluntary intake of digestible straw organic matter (DOMI) consistently varied from 15.2 to $20.9g{\cdot}kg^{-0.75}$ between straw varieties, averaged over locations, years and seasons, despite considerable variation between individual batches. This variation in the nutritive value of the straw was independent of straw and grain yield, so it would seem that there is scope for selection of rice varieties with straw of higher nutritive value. The variation in DOMI of straw among location of growth, year and season, was of a magnitude similar to the improvement brought about by urea-ammoniation. The in sacco degradation characteristics and digestibility of rice straw residues were superior to those of the offered straw. This can be attributed to a preference for rice straw leaves relative to stems. Averaged over location of growth, year and season, characteristics of in sacco degradation, i.e. the rate of fermentative degradation and the truly undegradable fraction, emerged as accurate predictors of the nutritive value of rice straw.

• Archives of Pharmacal Research
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• v.10 no.1
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• pp.42-49
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• 1987

This study is to evaluate the potential use of aclarubicin-loaded gelatin microspheres as an intravascular biodegradable drug delivery system for the regional cancer therapy. The diameter of the microspheres prepared by water in oil emulsion polymerization could be controlled by adjusting the stirring rate in the range of 10-50 $\mu$m : D(in $\mu$m) = -73.8 log (rpm) + 262.7. The addition of proteolytic enzyme increased the in vitro aclarubicin release but it did not change the amount of the initial burst release which reached about 45%. Microspheres injected intravenously into the mouse tail vein embolized only to the lung when observed by fluorescence microscopy. From histological examination following injection of gelatin microspheres into mouse femoral muscle, mild inflammation was observed from the appearance of neutrophils after 2 days and rapid repair process was confirmed thereafter. Biodegradation process of gelatin microspheres lodged on the pulmonary capillary bed was followed up by microscopic observation; degradation was taking place by about 36 hrs, followed by severe damage on the spheerical shape and microspheres was no longer found 10 days after injection.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.439-442
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• 2006

We evaluated a-Si:H TFTs fabricated on polyimide substrate (PI) at the highest temperature of $160^{\circ}C$ with uniaxial and tensile strain to imitate flexible display. With tensile strain, the threshold voltage of a-Si:H TFTs have positive shift due to extra dangling bond formation in a-Si:H layer. However, no significant degradation of the subthreshold swing and effective mobility with tensile strain of a-Si:H TFTs indicates the similar level of band tail state. The metal wire with the width of $10\;{\mu}m$ for connection on flexible substrate can sustain with curvature radius 2.5 cm.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.2
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• pp.49-53
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• 2005

The current drive in a MOSFET is limited by the intrinsic channel resistance. All other parasitic elements in a device structure perform significant functions leading to degradation in the device performance. These other resistances must be less than 10$\%$-20$\%$ of the channel resistance. To meet the necessary requirements, the methodology of separation and quantification of those resistances should be investigated. In this paper, we developed an extraction method for the resistances using calibrated TCAD simulation. The resistance of the extension region is also partially determined by the formation of a surface accumulation region that gathers below the gate in the tail region of the extension profile. This resistance is strongly affected by the abruptness of the extension profile because the steeper the profile is, the shorter this accumulation region will be.

• Preventive Nutrition and Food Science
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• v.4 no.2
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• pp.103-106
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• 1999

Fish sauce is a liquid form of salt-fermented fish and has played an important role in Korean dietary life. Fish sauce was manufactured by utilizing Alaska pollack scrap from Himedara(seasoned and dried Alaska pollack tail) processing . In addition, the effects of squid viscera as a fermentation enhancer were also evaluate.Ph of Alaska plllack scrap sauce with squid viscera was lower than that of control over the entire fermentation process. Squid viscera acceleraged the production of amino-nitrogen, VBN , TBA and free amino acids, and the degradation of IMP and Inosine. The addition of squid viscera and koji at 5% concentration, respectively , also accelerated the digestion of Alaska pollack scrap and was similar to the results of squid viscera at 10% concentration.

• Journal of Communications and Networks
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• v.6 no.2
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• pp.133-146
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• 2004

Recently, many active queue management (AQM) algorithms have been proposed to address the performance degradation. of end-to-end congestion control under tail-drop (TD) queue management at Internet routers. However, these AQM algorithms show performance improvement only for limited network environments, and are insensitive to dynamically changing network situations. In this paper, we propose an adaptive queue management algorithm, called PID-controller, that uses proportional-integral-derivative (PID) feedback control to remedy these weak-Dalles of existing AQM proposals. The PID-controller is able to detect and control congestion adaptively and proactively to dynamically changing network environments using incipient as well as current congestion indications. A simulation study over a wide range of IP traffic conditions shows that PID-controller outperforms other AQM algorithms such as Random Early Detection (RED) [3] and Proportional-Integral (PI) controller [9] in terms of queue length dynamics, packet loss rates, and link utilization.

• Macromolecular Research
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• v.11 no.1
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• pp.19-24
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• 2003

Polymeric gene delivery system attracts profound attention as it shows less toxicity, versatility, and reasonable gene expression efficiency. Terplex system, a synthetic biopolymeric gene delivery system consisting of stearyl poly-L-lysine (stearyl-PLL) and low density lipoprotein (LDL) was evaluated for its body distribution of gene expression of exogenously administered pDNA after tail-vein injection in mice. Kidney and spleen are two major organs with highest gene expression, whereas liver and heart showed marginal gene expression among the organs examined. Hemolytic effect of the terplex system was evaluated using human red blood cells, where terplex system did not cause significant hemolysis at the concentrations above the experimental ranges, although unmodified PLL or stearyl-PLL without LDL did. Serum stability of terplex system against enzymatic degradation was also significantly enhanced, presumably due to the steric stabilization from the polymers. Based on these findings and along with its high in vitro transfection efficiency, terplex system could serve as a safe and efficient polymeric gene delivery system with many applications for the in vivo gene therapy.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1348-1357
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• 2011

The objective of this study was to compare the effect of Butylated Hydroxy Toluene (BHT), Pentoxifylline (PTX) and ${\alpha}$-tocopherol (Vit E) on semen quality parameters of Karan Fries bulls. The fortification of extender by various semen additives improves motility as well as fertility of spermatozoa. Split samples of 24 ejaculates of four Karan Fries bulls were extended in extender with or without various additives such as BHT, PTX and Vit E, and performance was evaluated at an interval of 0, 24, 48 and 72 h at refrigerated temperature (4-$7^{\circ}C$). Results of the present study revealed that addition of BHT, PTX and Vit E in extender improved sperm cell function, such as motility, viability, HOST, and acrosome integrity, as compared to the control during liquid storage up to 48 h of preservation at refrigerated temperature. There was no significant (p<0.05) difference between any of the additives up to 48 h of preservation. Overall, the results showed a significant (p<0.05) deterioration in motility after each storage interval. The results showed a significant deterioration in the acrosome integrity and plasma membrane integrity up to 48 h; subsequently, there was not much degradation of both the semen quality parameters. There was a significant increase in spermatozoal tail and total abnormality after each storage interval at refrigerator temperature (4 to $7^{\circ}C$); however, the head and mid-piece abnormalities were almost unaffected. Tail and total abnormality were least in extender fortified with BHT, PTX and Vit E at different hours of incubation as compared to the control. The addition of 1.5 mM BHT, 3.6 mM PTX and 1 mg/ml Vit E in the semen extender has more beneficial effect in terms of semen quality and preservability of spermatozoa.

• The Transactions of the Korea Information Processing Society
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• v.7 no.11S
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• pp.3723-3731
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• 2000

Recently, the growth of applications and services over high-speed Internet increase, ATM networks as wide area back-bone has been a major solution. The conventional TCP suite is still the standard protocol used to support upper application on current Internet and uses a window based protocol for flow control in the transport layer. When TCP data uses the UBR service in ATM layer, the control method is also buffer management. If a cell is discarded in ATM layer. one whole packet of TCP will be lost. Which is responsible for most TCP performance degradation and do not offer sufficiently QoS. To solve this problem, Several dropping strategies, such as Tail Drop, EPD, PPO, SPD, FBA, have been proposed to improve the TCP performance over ATM. In this paper, to improve the TCP fairness of end to end, we propose a packet dropping scheme algorithm using two fixed threshold. Under similar condition, we compared our proposed scheme with other dropping strategies. Although the number of VC is increased, simulation results showed that the proposed scheme can allocate more fairly each VC than other schemes.