• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.185-192
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• 2010

The chemical-looping combustion(CLC) has advantages of no energy loss for separation of $CO_2$ without $NO_x$ formation. This CLC system consists of oxidation and reduction reactors where metal oxides particles are circulating through these two reactors. In the present study, the reaction kinetic equations of iron oxide oxygen carriers supported on bentonite have been determined by the shrinking core model. Based on the reactivity data, design values of solid circulation rate and solids inventory were determined for the rector. Two types of interconnected fluidized bed systems were designed for CLC application, one system consists of a riser and a bubbling fluidized bed, and the other one has a riser and two bubbling fluidized beds. Solid circulation rates were varied to about $30kg/m^2s$ by aeration into a loop-seal. Solid circulation rate increases with increasing aeration velocity and it increases further with an auxiliary gas flow into the loop-seal. As solid circulation rate is increased, solid hold up in the riser increases. A typical gas leakage from the riser to the fluidized bed is found to be less than 1%.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.2
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• pp.181-189
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• 2011

Cryopreservation protocols induce partially irreversible damage to mammalian sperm plasma membranes. Previous studies have indicated that adding cholesterol to the plasma membrane, as cholesterol-loaded-cyclodextrins, improves cryosurvival of sperm. Therefore, the purpose of this study was to determine if treating sperm of Markhoz bucks with cholesterol-loaded-cyclodextrins (CLC) (0, 0.75, 1.5, 2.25 and 3 mg/ml diluted $240{\times}10^6$ sperm/ml) in Tris-citric acid-glucose diluents with and without egg yolk (containing 5% glycerol) would improve the post-thaw sperm quality. The motion characteristics were evaluated with a Computer Assisted System Analyzer (CASA); acrosome integrity and vitality were measured with the triple-stain technique. Samples were recovered before and after freezing by means of putting straws into $37^{\circ}C$ water for 30 sec and then parameters were assessed. The results showed that the treatments significantly affected motility, progressive motility, recovery rate, curvilinear velocity, beat cross frequency, live sperm with reacted acrosome, live sperm with unreacted acrosome, dead sperm with reacted acrosorne, and dead sperm with unreacted acrosome during freezing (p<0.05). However; no significant differences were found for average path velocity, straight line velocity, amplitude of lateral head displacement, straightness and linearity (p>0.05). The best results were observed for extender containing 2.25 mg/ml ($240{\times}10^6$ sperm/ml) CLC supplemented with 2.6% egg yolk. In conclusion, the findings of this study indicate improved Markhoz sperm viability and motility following treatment in the presence of egg yolk.

• Geotechnical Engineering
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• v.9 no.4
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• pp.55-64
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• 1993

The Undrained creep tests on the normally consolidated clays with four different consolication ratios(c3c'/clc': 1.0, 0.7, 0.5, 0.4) were performed to investigate the effects of avisotropic consolidation on the undrained creep rupture behavior. The elapsed time to a certain minimum strain rate is decreased with decreasing the value of the consolidation pressure ratio, and the elapsed time to rupture for a certain minimum strain rate is also decreased with decreasing the ratio. The upper yield strength obtained from the equation suggested by Finn and Shead(1.) is coincided well with the creep strength irrespective of the magnitude of the consolidation pressure ratio, and the normallised upper yielding strength by mean confining pressure is decreased with increasing the consolidation pressure ratio. The critical strain for creep rupture, the strain at min. strain rate, is constant irrespective of the magnitude of creep stress, but it increased exponentially with increasing the ratio, It accordingly is dangerous that the potential of in-situ creep rupture is estimated only by the creep rupture test on the isotropically consolidated clay in case of K0-value below 1.0.

• Journal of the Korean Institute of Rural Architecture
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• v.18 no.3
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• pp.9-16
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• 2016

This study aimed to clarify the multifunctional services and space composition in the process of developing a multifunctional long-term care program in small elderly care facilities in Japan. We collected data about multifunctional long-term care at small facilities from the Community Life Support Center (CLC), a Japanese non-profit corporation, and conducted an interview survey of the members of the CLC's secretariat in 2014. Furthermore, we selected 3 Japanese pioneering care facilities (known as takurosho), and conducted interview surveys and data collection to clarify in detail the space composition and process of development of multifunctional long-term care at small facilities. Four distinct results were found. First, the facilities had gradually increased non-institutional services, including visitation, overnight stays, and long-term stays, to fit the needs of users and their families. Secondly, in the 1990s, they could offer both non-institutional and institutional services at the same facility, but after the long-term care insurance system began in 2000, non-institutional long-term stay services were not allowed. Third, the facilities had built extensions or extra rooms in response to increases in multifunctional services and users. These rooms had common characteristics, with sitting rooms at the center of the facility. Lastly, the maximum number of service users at each of the 3 facilities was limited to 15, to maintain a small scale. However, as the size of facilities was increased through building extensions or remodeling, the overall amount of area available to users increased.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.3
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• pp.152-162
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• 2003

In this paper, Binary to Quaternary Converter(BQC), Quaternary to Binary Converter(QBC) and Quaternary inverter circuit, which is the basic logic gate, have been proposed based on voltage mode. The BQC converts the two bit input binary signals to one digit quaternary output signal. The QBC converts the one digit quaternary input signal to two bit binary output signals. And two circuits consist of Down-literal circuit(DLC) and combinational logic block(CLC). In the implementation of quaternary inverter circuit, DLC is used for reference voltage generation and control signal, only switch part is implemented with conventional MOS transistors. The proposed circuits are simulated in 0.35 ${\mu}{\textrm}{m}$ N-well doubly-poly four-metal CMOS technology with a single +3V supply voltage. Simulation results of these circuit show 250MHz sampling rate, 0.6mW power consumption and maintain output voltage level in 0.1V.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1070-1077
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• 2005

The purpose of this study is to establish a proper criterion for the constant rate of loading consolidation(CRLC) test which is a kind of the continuous loading consolidation(CLC) and widely used as alternative methods to the incremental loading consolidation(ILC)test. With those results, the preconsolidation pressure estimated by the CRLC test turned out to be comparatively larger than that of the ILC test, and it is increased in proportion to the applied loading rates. However, the compression index in the CRLC test is less influenced on by the loading rates. The coefficient of consolidation and permeability in the CRLC test are dependent on excess pore pressure ratio mainly. In other words, if the pore pressure ratios are too low, the coefficient of consolidation and permeability become smaller than those of the ILC test. On the other hand, if the excess pore pressure ratios are too high, the coefficient of consolidation and permeability become so larger than those of the ILC test. Therefore, loading rates should be carefully determined to generate proper excess pore pressure ratio inside the soil specimen. From this study, good results are obtained from the CRLC test if the excess pore pressure ratios were in the range of 2.5 to 6.0 %, performed with loading rates between 0.0015 and 0.005 $kgf/cm^2/min$.

• Clean Technology
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• v.24 no.1
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• pp.63-69
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• 2018

The reduction reaction characteristics and physicochemical properties were studied for the selection of oxygen carrier, which is the core of the chemical looping combustion (CLC) technology. Fuel conversion and $CO_2$ selectivity of oxygen carrier according to the concentration of reducing gas and the reduction temperature using three kinds of oxygen carrier (SDN70, N018-R2, N016-R4) were measured and compared. In addition, Attrition Index (AI) and BET surface area were measured to analyze the attrition resistance and the surface characteristics of the oxygen carrier. As a result, it was confirmed that all three kinds of oxygen carrier were suitable for use in chemical roofing combustion system, and the best particle was determined to be N016-R4.

• Journal of Microbiology and Biotechnology
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• v.33 no.7
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• pp.857-863
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• 2023

Pathogenic bacteria that colonize the human intestinal tract have evolved strategies to overcome acidic conditions when they pass through the gastrointestinal tract. Amino acid-mediated acid resistance systems are effective survival strategies in a stomach that is full of amino acid substrate. The amino acid antiporter, amino acid decarboxylase, and ClC chloride antiporter are all engaged in these systems, and each one plays a role in protecting against or adapting to the acidic environment. The ClC chloride antiporter, a member of the ClC channel family, eliminates negatively charged intracellular chloride ions to avoid inner membrane hyperpolarization as an electrical shunt of the acid resistance system. In this review, we will discuss the structure and function of the prokaryotic ClC chloride antiporter of amino acid-mediated acid resistance system.

• Asia Pacific Journal of Corpus Research
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• v.4 no.1
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• pp.25-42
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• 2023

The number of studies on data-driven learning (DDL) has increased in recent years, and DDL's overall effectiveness as an L2 (second language) teaching methodology has been reported to be high. However, the degree of its effectiveness in grammar instruction, particularly for the goal of correcting errors in L2 writing, is still unclear. To provide guidelines for focused grammar instruction with DDL in the Japanese classroom setting, we aimed to identify the typical grammatical errors made by Japanese learners in the Cambridge Learner Corpus First Certificate in English (CLC FCE) dataset. The results revealed that three error types (nouns, articles, and prepositions) should be addressed in DDL grammar instruction for Japanese English as a foreign language (EFL) learners. In light of the findings, pedagogical implications and suggestions for future DDL research and practice are discussed.

• Journal of the Korean Institute of Navigation
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• v.17 no.4
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• pp.73-87
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• 1993

As a result of accepting the '71 FUND Convention and enforcing the Oil Pollution Compensation Act 1992, we observed some benefits and costa. This paper analyses those benefits and costs and suggests se-veral key policy recommendations for the estasblishment of an effective oil pollution compensation regime in Korea. This paper identifies the said benefits and costs as follows : First, by establishing the oil pollu-tion compensation system as same as the international level, most of small and medium size of oil pollution damage which are caused by coastal tankers will be compensated by FUND. Second, most of oil pollution damage which are not covered by '69 CLC will be compensated by FUND. Third, some parts of FUND Contribution Fee and CRISTAL Contribution Fee to be charged by major oil companies will be doubled. However the limit of international oil pollution compensation system and the loophole outside the Oil Pol-lution Compensation Act 1992 suggest followings : 1) Radical risk management and insurance manage-ment of ocean going tanker owners, 2) Establishment of oil pollution claim settlement system, 3) Enforce-ment of crew and ship management for coastal tanker and 4) Establishment of Korean P & I Club.