• Title/Summary/Keyword: 효율저하

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Economic and Political Responses to Globalization: Economic Restructuring and Local Government as an Entrepreneur (세계화에 따른 경제${\cdot}$정치적 동향: 경제재구조와 기업가로서의 지방정부)

  • Koh, Tae-Kyung
    • Journal of the Korean Geographical Society
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    • v.31 no.4
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    • pp.662-671
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    • 1996
  • Since the world's economic and political structures have changed, the term 'globlization' has shown up as a dominant power and as a necessity for regional and national development. Each nation is responding to the globalization process economically and politically in various ways. In general, however, the economic response to the globalization is economic restructuring from the Fordist industries to 'flexible specialization'. And the political response to the globalization is 'global localization' as a new type of local politics(i.e., local policy activism or growth-enhancing local development policies). The crisis of Fordism shifted the role of local governments towards more involovement with local economic development. Local governments are mobilizing for loca economic development, they are taken into a process of institutional change that tends to redefine their responsibilities inside the state. Local governments thus tend to act as an entrepreneur in order to restructure theiir local economies and to compete with other national and international regions. State restructuring towards enerepreneurialism and efficient regional policy pursuing a pro-growth coalition trategy is chosen as a new mode of regulation for the post-Fordism at the local level. The flexible specialization as the post-Fordist economy and the local government as an entrepreneur are the global choice for globalization and a post-Fordist society. The paper focuses on the regulation theory which comprises the political economic perspective on resturcturing. Economic restructuring and state restructuring will be discussed in detail. And the paper tries to combine the economic globalization and the global localization as economic and political responses to globalization.

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The Effect of Cold Shock on Function and Morphology of Dog Epididymal Spermatozoa (개에서 cold shock이 정소상체유래의 정자의 기능과 형태에 미치는 영향)

  • Yu Il-jeoung
    • Journal of Veterinary Clinics
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    • v.21 no.4
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    • pp.329-335
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    • 2004
  • Dog spermatozoa were recovered from the caudae epididymides of 23 domestic dogs which were 11 pure breed and 12 mix-breed dogs ranging in age from 0.6 to 3 years. The experimental designs were as follows: 1) the effect of chilling to 0. 10 or 37$^{\circ}C$. 2) the kinetics of chilling injury at 0 or 4$^{\circ}C$, and 3) the effect of sugars at $0^{\circ}C$. Viable spermatozoa were recovered by percoll gradient separation and adjusted to 5${\times}$10$^{7}$ spermatozoa/ml. In experiment 1, spermatozoa were diluted with 0.33 M glucose supplemented with 3% BSA (G-BSA) at 1:2 dilution. Spermatozoa were loaded into straws and exposed at 0, 10 or 37$^{\circ}C$ for 30 min. In experiment 2, spermatozoa were prepared as the experiment 1 and exposed for 0.5, 5, 15, or 30 min at 0 or 4$^{\circ}C$. In experiment 3, spermatozoa were diluted with different sugars (0.33 M galactose, glucose, fructose, mannitol, lactose, sucrose, raffinose) and cooled to $0^{\circ}C$ for 30 min. Sperm membrane integrity, motility and acrosome integrity were assayed after rewarming at 37$^{\circ}C$ for 5 min. Sperm motility and membrane integrity abruptly decreased with decreasing temperature but acrosome integrity gradually decreased (P<0.05). Sperm motility was more sensitive to cold shock than membrane integrity and acrosome integrity. Spermatozoa cooled to $0^{\circ}C$ were more damaged than those at 4$^{\circ}C$. Sperm motility was not different among exposed times at both. 0 and 4$^{\circ}C$. However, membrane integrity of spermatozoa exposed for 30 min at both 0 and 4$^{\circ}C$ was significantly lower (P<0.05). Spermatozoa diluted in 0.33 M fructose or galactose showed lower motility and higher morphological abnormality with coiled tail at $0^{\circ}C$. These sperm characteristics were strongly related. These results indicate that dog epididymal spermatozoa are relatively sensitive to rapid cooling and higher morphological abnormality at $0^{\circ}C$ was shown in spermatozoa diluted in fructose and galactose.

Method for increasing rail operation capacity of capital high speed rail with expanding the high speed railway service (고속철도 서비스 확대를 위한 수도권 고속철도 확충 방안 고찰)

  • Roh, Beung-Guk;Kim, Young-Bea;Shin, Dong-Won
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.1254-1268
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    • 2009
  • In 1998, because of the economic crisis called IMF Crisis in Korea, Kyungbu high speed railway project could run by modifying the original plan to open it as a 1st phase only by utilizing the existing railway lines from Seoul to Siheung and the other one from Daegu to Pusan. The modified plan includes that the line from Daegu to Pusan will be constructed as a second phase in next time. Starting railway operation with the changed plan, the combined application operation of high speed rail, passenger rail and freight rail was caused partly from Seoul to Siheung to run into capital area. As a result, the opinion for additional railway line construction is insisted continuously because the operation volume of passenger rail was forced to be reduced, the service quality of it was decreased and it became difficult to add new high speed services. Moreover, with regard to Honam high speed rail, the new construction plan of station in Kangnam metro area as a basement station for starting from Suseo was changed to the plan of turning out at Osong because of the economic effectiveness and this kept resident people in Kangnam metro area and southern Kyungki area unable to get the opportunity of high speed rail service benefit. After beginning of Kyungbu high speed railway operation, national transportation system developments are focused on high speed rail, and when the second phase construction of Kyungbu high speed rail, beginning operation of Kyungjeon line, Jeolla line double track construction, Honam high speed rail in 2014, is completed, the demand for high speed rail will be increased and it is unavoidable to make Kwangmyung station as a basement station and to reduce the number of passenger rail operation. At this moment, it is valuable to consider adding the railway line capacity in capital area to improve the transferring service for citizen who live in area without Kyungbu high speed rail station and to expand the service area from Kangbuk to Kangnam and southern Kyungki area. Accordingly, in this paper, the effective rail operation method, facility plan and the other issue to be reviewed for increasing capital high speed railway lines will be mentioned.

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Effect of Ethanol Extracts of Goat's Beard on Streptozotocin Induced Diabetic Symptoms and Oxidative Stress in Rats (삼나물 에탄올 추출물이 Streptozotocin으로 유발한 흰쥐의 당뇨증상과 산화적 스트레스에 미치는 영향)

  • Shin, Jong-Wook;Lee, Sang-Il;Woo, Mi-Hee;Kim, Soon-Dong
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.6
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    • pp.939-948
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    • 2008
  • The effects of goat's beard (Aruncus dioicus var ramtschaticus Hara) ethanol extracts (AD) on the streptozotocin-induced diabetic symptoms and oxidative stress in rats were assessed. Experimental plots were divided into normal controls (NC), diabetes controls (DM), diet with 0.3% AD after diabetes induction (SA), and diet with 0.6% AD after diabetes induction (SB), then fed for 5 weeks. In the SA and SB groups as compared with the DM group, diabetic symptoms including weight loss, increase in feed and water intake, and enlargement of the liver and kidney were improved. The levels of blood glucose and serum fructosamine were reduced by $17.9{\sim}27.2%$ and $25.6{\sim}32.6%$, respectively. The activities of alanine aminotransferase, aspartate aminotransferase and the levels of triglycerides, total cholesterol, and LDL-cholesterol in the serum were reduced by $25.6{\sim}30.3$, $42.37{\sim}55.51$, $26.85{\sim}30.44$ and $37.29{\sim}39.11%$, respectively, whereas the level of HDL-cholesterol was increased by $37.29{\sim}39.11%$. Hepatic total (T) and O type (O) activities of xanthine oxidoreductase, O/T ratio(%) and level of lipid peroxide were significantly decreased, while the level of glutathione was increased, and also the activities of superoxide dismutase and glutathione S-transferase were increased by $56.84{\sim}94.90%$ and $57.14{\sim}68.92%$, respectively. In the above results, it was noted that AD has an antidiabetic effect which alleviated hyperglycemia and the AD reduced and/or prevented the tissue damage caused by diabetes yia the inhibition of reactive oxygen species (ROS) generating systems concurrent with an increase in ROS scavenging.

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Current Status and Prospects of High-Power Fiber Laser Technology (Invited Paper) (고출력 광섬유 레이저 기술의 현황 및 전망)

  • Kwon, Youngchul;Park, Kyoungyoon;Lee, Dongyeul;Chang, Hanbyul;Lee, Seungjong;Vazquez-Zuniga, Luis Alonso;Lee, Yong Soo;Kim, Dong Hwan;Kim, Hyun Tae;Jeong, Yoonchan
    • Korean Journal of Optics and Photonics
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    • v.27 no.1
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    • pp.1-17
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    • 2016
  • Over the past two decades, fiber-based lasers have made remarkable progress, now having reached power levels exceeding kilowatts and drawing a huge amount of attention from academy and industry as a replacement technology for bulk lasers. In this paper we review the significant factors that have led to the progress of fiber lasers, such as gain-fiber regimes based on ytterbium-doped silica, optical pumping schemes through the combination of laser diodes and double-clad fiber geometries, and tandem schemes for minimizing quantum defects. Furthermore, we discuss various power-limitation issues that are expected to incur with respect to the ultimate power scaling of fiber lasers, such as efficiency degradation, thermal hazard, and system-instability growth in fiber lasers, and various relevant methods to alleviate the aforementioned issues. This discussion includes fiber nonlinear effects, fiber damage, and modal-instability issues, which become more significant as the power level is scaled up. In addition, we also review beam-combining techniques, which are currently receiving a lot of attention as an alternative solution to the power-scaling limitation of high-power fiber lasers. In particular, we focus more on the discussion of the schematics of a spectral beam-combining system and their individual requirements. Finally, we discuss prospects for the future development of fiber laser technologies, for them to leap forward from where they are now, and to continue to advance in terms of their power scalability.

Preparation of Polystyrene Beads by Suspension Polymerization with Hydrophobic Silica as a Stabilizer in Aqueous Solution (소수성 실리카를 안정제로 이용하는 수용액 상에서의 현탁중합법에 의한 폴리스티렌 입자 합성)

  • Park, Moon-Soo
    • Polymer(Korea)
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    • v.30 no.6
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    • pp.498-504
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    • 2006
  • A suspension polymerization of styrene In aqueous phase was employed to study if polystyrene particles ranging from 1 to $20{\mu}m$ can be produced. Hydrophobic silica was selected as a stabilizer and azo-bisisobutyronitrile (AIBN) as an initiator. Polymerization reaction was carried out at a selected temperature in the range of $65{\sim}95^{\circ}C$. Stabilizer concentration was varied from 0.17 to 3.33 wt% compared to the water while the concentration of the initiator was raised from 0.13 to 6.0 wt% compared to the monomer. Dispersion of hydrophobic silica into the water phase was achieved by precise control of pH. Optimum dispersion of silica was obtained at pH 10. Average particle diameter decreased with increasing amounts of stabilizer concentration initially, exhibiting the minimum average diameter at 1.67 wt% of stabilizer concentration, after which it started to Increase. It is speculated that an excessive presence of stabilizer encouraged a secondary reaction in the reaction medium, which led to particle agglomeration, and as a result an increase in average particle diameter. Molecular weight was found to be independent of stabilizer concentration between 0.13 and 1.00 wt% whereas, it increased when stabilizer concentration exceeded 1.67 wt%. Variation of molecular weight was probably caused by the reduced activity and efficiency of initiator due to the high concentration of silica, and the secondary reaction in the reaction medium, as well. An increase in the Initiator concentration and/or reaction temperature resulted in an increase in both reaction rate and particle diameter. Consequently, we have confirmed that spherical polystyrene particles with $1{\sim}20{\mu}m$ in diameter can be prepared by careful selection of the concentration of stabilizer, initiator, pH and reaction temperature.

The Effect of Extract Powder from Fresh and Black Garlic on Main Components in Serum and Organs of Streptozotocin-Induced Diabetic Rats (생마늘 및 흑마늘 추출분말이 Streptozotocin 유발 당뇨 흰쥐의 혈청 및 장기 내 주요성분에 미치는 영향)

  • Kang, Min-Jung;Lee, Soo Jung;Sung, Nak Ju;Shin, Jung-Hye
    • Journal of Life Science
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    • v.23 no.3
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    • pp.432-442
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    • 2013
  • In this study, we examined the biological activity and synergistic effects of an extract powder of 1% and 3%, each fresh (FGP) and black garlic (BGP) in streptozotocin-induced diabetic rats. Blood glucose content was significantly lower in FGP and BGP groups than control group. Glycosylated Hb was significantly higher in streptozotocin induced diabetic control group than normal group, but significantly lower in FGP and BGP groups. Total cholesterol content of the FGP and BGP groups were lower than control group, but not shown the significant difference between garlic fed groups. HDL-cholesterol concentrations of the FGP and BGP fed groups were significantly higher than control group, except of 1% BGP group. LDL and VLDL-cholesterol contents were significantly lower in 3% FGP group, and the same tendency atherogenic index and cardiac risk factor. GOT, GPT, and ${\gamma}$-GTP activity of serum were lower in FGP and BGP fed groups than control group. Glycogen contents in liver significantly higher than control group, and has not significantly difference between normal group. TBARS content was no significantly difference in the liver and serum, but in the kidney, 3% FPG and BGP fed groups were significantly lower than other experimental group. DPPH radical scavenging activity of liver has not significant difference among experimental groups, but activity was higher garlic extract powder fed groups in serum and kidney. These results indicate that dietary supplements of fresh and black garlic extract powder was contributed to lower of blood glucose, loss prevention of glycogen in liver and improve of lipid metabolism.

Electrochemical Characterization of Anti-Corrosion Film Coated Metal Conditioner Surfaces for Tungsten CMP Applications (텅스텐 화학적-기계적 연마 공정에서 부식방지막이 증착된 금속 컨디셔너 표면의 전기화학적 특성평가)

  • Cho, Byoung-Jun;Kwon, Tae-Young;Kim, Hyuk-Min;Venkatesh, Prasanna;Park, Moon-Seok;Park, Jin-Goo
    • Journal of the Microelectronics and Packaging Society
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    • v.19 no.1
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    • pp.61-66
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    • 2012
  • Chemical Mechanical Planarization (CMP) is a polishing process used in the microelectronic fabrication industries to achieve a globally planar wafer surface for the manufacturing of integrated circuits. Pad conditioning plays an important role in the CMP process to maintain a material removal rate (MRR) and its uniformity. For metal CMP process, highly acidic slurry containing strong oxidizer is being used. It would affect the conditioner surface which normally made of metal such as Nickel and its alloy. If conditioner surface is corroded, diamonds on the conditioner surface would be fallen out from the surface. Because of this phenomenon, not only life time of conditioners is decreased, but also more scratches are generated. To protect the conditioners from corrosion, thin organic film deposition on the metal surface is suggested without requiring current conditioner manufacturing process. To prepare the anti-corrosion film on metal conditioner surface, vapor SAM (self-assembled monolayer) and FC (Fluorocarbon) -CVD (SRN-504, Sorona, Korea) films were prepared on both nickel and nickel alloy surfaces. Vapor SAM method was used for SAM deposition using both Dodecanethiol (DT) and Perfluoroctyltrichloro silane (FOTS). FC films were prepared in different thickness of 10 nm, 50 nm and 100 nm on conditioner surfaces. Electrochemical analysis such as potentiodynamic polarization and impedance, and contact angle measurements were carried out to evaluate the coating characteristics. Impedance data was analyzed by an electrical equivalent circuit model. The observed contact angle is higher than 90o after thin film deposition, which confirms that the coatings deposited on the surfaces are densely packed. The results of potentiodynamic polarization and the impedance show that modified surfaces have better performance than bare metal surfaces which could be applied to increase the life time and reliability of conditioner during W CMP.

Optimizing Surfactant-Enhanced Solubilzation of LNAPL from Soil in Saturated Zone (포화지층내 저비중 비수용성 유기용매의 용해제거를 위한 계면활성제법의 최적 조작인자 도출)

  • 이재원;박규홍;박준범
    • Journal of the Korean Geotechnical Society
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    • v.15 no.2
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    • pp.153-164
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    • 1999
  • The solubilization of BTEX was evaluated in aqueous surfactant solutions with and without several additives. Anionic surfactant(Sodium Dodecyl Sulfate, SDS) and nonionic surfactants (NEODOL(equation omitted)25-3 and $SOFTANOL\circledR-90$ were used as test surfactants. The effects of surfactant HLB(Hydrophile-Lipophile Balance) Number and hydrocarbon molar volume and polarity of BTEX on the MSR(Molar Solubilization Ratio), micelle-water partition coefficient of BTEX, and CMC(C,itical Micelle Concentration) were investigated. Optimizing treatment conditions applicable to enhanced solubilization was also studied by manupulating salinity or electrolyte control with additives of ethyl alcohol, hydrotrope, and electrolyte solution. The most effective surfactant for solubilization was found $SOFTANOL\circledR-90$, since HLB number of 13.6 is similar to those values of BTEX ranging between 11.4 and 12.2, which was also proved experimentally. Ethyl alchohol of 3% was the most effective additives in reducing CMC and improving solubilization among the conditions using SDS, NEODOL(equation omitted)25-3, and $SOFTANOL\circledR-90$ with three additives. The partitioning of BTEX between surfactant micelles and aqueous solutions was characterized by a mole fraction micelle-phase/aqueous phase partion coefficient, $K_m$. Values of log $K_m$. for BTEX compounds in surfactant solutions of this study range from 2.95 to 3.76(100mM SDS) and 2.95 to 3.49(117mM $SOFTANOL\circledR-90$. Log $K_m$ appears to be a linear function of log $K_{ow}$ for SDS and $SOFTANOL\circledR-90$. A knowledge of partitioning of BTEX in aqueous surfactant system can be a prerequisite for the understanding of the behavior of hydrophobic organic compounds in soil-water systems in which surfactants play a role in remediation of contaminated soil and facilitated transport.

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A Experimental Study on Exclusion Ability of Riprap into Bypass Pipe (저층수 배사관 내 유입된 사석 배출능력에 대한 연구)

  • Jeong, Seok Il;Lee, Seung Oh
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.1
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    • pp.239-246
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    • 2017
  • There are various transversal structures (small dams or drop structures) in median and small streams in Korea. Most of them are concrete structures and it is so hard to exclude low-level water. Unless drainage valves and/or gates would not be installed near bottom of bed, sediment from upstream should be deposited and also contaminants attached to the sediments would devastatingly threaten the water quality and ecosystem. One of countermeasures for such problem is the bypass pipe installed underneath the transversal structure. However, there is still issued whether it would be workable if the gravels and/or stones would roll into and be not excluded. Therefore, in this study, the conditions to exclude the rip stone which enter into the bypass pipe was reviewed. Based on sediment transport phenomenon, the behavior of stones was investigated with the concepts from the critical shear stress of sediment and d'Alembert principle. As final results, the basis condition (${\tau}_c{^*}$) was derived using the Lagrangian description since the stones are in the moving state, not in the stationary state. From hydraulic experiments the relative velocity could be obtained. In order to minimize the scale effect, the extra wide channel of 5.0 m wide and 1.0 m high was constructed and the experimental stones were fully spherical ones. Experimental results showed that the ratio of flow velocity to spherical particle velocity was measured between 0.5 and 0.7, and this result was substituted into the suggested equation to identify the critical condition wether the stones were excluded. Regimes about the exclusion of stone in bypass pipe were divided into three types according to particle Reynolds number ($Re_p$) and dimensionless critical shear force (${\tau}_c{^*}$) - exclusion section, probabilistic exclusion section, no exclusion section. Results from this study would be useful and essential information for bypass pipe design in transveral structures.