• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2007년도 추계학술발표대회
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• pp.1031-1032
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• 2007

최근 정보통신기술을 포함한 IT 기술의 발전은 매우 빠른 속도로 전개되어 가고 있으며, 이러한 기술 발전에 힘입어 매우 다양한 형태의 통신단말들이 지속적으로 출현하고 있다. 향후 통신환경은 광대역통합망(BcN)의 발전에 따라 지속적으로 변화되리라 예상되며, 이에 따라 통신단말기술의 발전도 병행되리라 예측된다. 본 논문은 현재까지의 통신단말기술에 대해 유형별로 분류하여 살펴보고, 향후 단말기술의 발전 방향을 조망해보고자 한다.

• 한국환경과학회지
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• 제23권8호
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• pp.1419-1428
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• 2014

Electron beam-induced grafting polymerization was employed to prepare Acrylic acid-grafted bacterial cellulose (BC-g-AAc). BC-g-AAc as an adsorbent was applied to remove heavy metals (e.g., As, Pb, and Cd). This study examined followings; morphological change of surface, adsorptive behavior of BC-g-AAc, and interpretation of adsorptive kinetics. Specific surface areas of BC and BC-g-AAc were $0.9527m^2g^{-1}$ for BC and $0.2272m^2g^{-1}$ for BC-g-AAc, respectively as measured by BET nitrogen adsorption, revealing the morphological change of the surface of BC-g-AAc. Batch adsorption test was performed to investigate adsorptive behavior of BC-g-AAc in aqueous solution. The amounts of Pb and Cd adsorbed on BC-g-AAc were $69mg\;g^{-1}$ and $56mg\;g^{-1}$, respectively. However, As was not adsorbed on BC-g-AAc due to its neutral nature. Both the Benaissa model and the Kurniawan model were applied in the study to interpret adsorptive kinetics. From the value of correction coefficient ($R^2$), adsorptive kinetics of Pb and Cd were subjected to Kurniawan model referred to pseudo-second-order. Taken together, the results of this study show that BC-g-AAc has potential as a heavy metal (eg., Pb, Cd)-adsorbent made of an environmentally friendly material.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.131-135
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• 2002

Acetobacter xylinum KJ1 efficiently producing bacterial cellulose(BC) in shaking culture was isolated from a rotten grape. The strain was used to investigate optimum operating conditions for increasing BC production and factorial design model was employed for the optimization. The results of experiments were statistically analyzed by SAS program. Reciprocal effects of each factors(carbon source concentration, shaking speeds(rpm), oxygen pressure, and CSL concentration) and culture condition of BC production were examined by getting regression equation of the dependent variable. Comparisons between experimental results and predicted results about BC concentration were done in total 24 experiments by combination of each factors using SAS program, and the correlation coefficients of BC concentration and BC yield were 0.91 and 0.81, respectively. The agitated cultures were performed in various operation conditions of factors which affected considerably to BC production in jar fermentor. The results showed that BC concentration was 11.67g/ L in 80 hours cultivation under the condition of carbon source concentration shaking speeds(rpm) : oxygen pressure: CSL concentration = 4% : 460rpm : 0.28 : 6%. On the other hand BC yield was 0.42g/g in 80 hours cultivation under the condition of carbon source concentration shaking speeds(rpm) : oxygen pressure: CSL concentration = 4% : 564rpm : 0.21 : 2%. The BC production could be enhanced up to more than 65.3% by factorial design. The result of a verifying experiment under the optimal conditions determined by the factorial design to the BC production showed that the model was appropriate by obtaining BC concentration of 11.02g/L in the optimum condition

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권6호
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• pp.79-94
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• 2011

Black carbon (BC), a kind of high surface area carbonaceous material (HSACM), was isolated from Andong lake sediment. Sorption and desorption kinetics of naphthalene (Naph) and phenanthrene (Phen) in organic carbon (OC) and BC in the Andong lake sediment were investigated. Several kinetic models such as one-site mass transfer model (OSMTM), two-compartment first-order kinetic model (TCFOKM), and a newly proposed modified two-compartment first-order kinetic model (MTCFOKM) were used to describe the sorption and desorption kinetics. The MTCFOKM was the best fitting model. The MTCFOKM for sorption kinetics showed that i) the sorbed amounts of PAHs onto BC were higher than those onto OC, consistent with BET surface area; ii) the equilibration time for sorption onto BC was longer than those onto OC due to smaller size of micropore ($11.67{\AA}$) of BC than OC ($38.18{\AA}$); iii) initial sorption velocity of BC was higher than OC; and iv) the slow sorption velocity in BC caused the later equilibrium time than OC even though the fast sorption velocity was early completed in both BC and OC. The MTCFOKM also described the desorption of PAHs from the OC and BC well. After desorption, the remaining fractions of PAHs in BC were higher than those in OC due to stronger PAHs-BC binding. The remaining fractions increased with aging for both BC and OC.

• 한국의류학회지
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• 제45권5호
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• pp.866-880
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• 2021

This study aimed to ex situ colorize laccase-entrapped bacterial cellulose (BC) with natural phenolic dyes, namely,madder, turmeric, and cochineal, and to determine the effect of laccase entrapment on the dyeability of BC using color strength (K/S) analysis. Results showed that laccase entrapment improved the dyeability of BC and that pre-entrapment was the most effective method, compared with meta-entrapment and post-entrapment methods. In addition, surface characterizations confirmed the successful entrapment of laccase inside the BC nanostructure and retention of the cellulosic and crystalline structures of BC. The washing durability test confirmed that the K/S value of BC had improved after laccase entrapment. Furthermore, laccase-entrapped BC colorized with cochineal dye had the highest washing durability due to the high molecular weight of cochineal dyerelative to the other dyes. This study suggests a novel method for enhancing the dyeability and washing durability of BC colorized ex situ with natural phenolic dyes by laccase entrapment.

• 경영과학
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• 제23권3호
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• pp.119-132
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• 2006

Since the guaranteed service quality(QoS) is spotlighted as a strategic competitive tool to Broadband Convergence Network(BcN) service providers, many scholars have dealt with QoS issues in the BcN environment. However, just a few researchers focus on end-users and most are lean toward service providers or technology itself. In this paper, therefore, we investigated how end-users could measure service quality in the BcN environment, and moreover, proposed the end-user oriented measurement guideline for BcN QoS. Through literature review and two surveys, four QoS dimensions and nineteen measurement items were derived from end-user's perspective. proposed QoS dimension and items would be utilized as meaningful tools for future BcN service.

• 한국대기환경학회지
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• 제31권5호
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• pp.472-481
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• 2015

Black carbon (BC) aerosols were monitored at the KIST site ($37.603^{\circ}N$, $127.046^{\circ}E$) and Cheonan-KOREATECH site ($36.766^{\circ}N$, $127.281^{\circ}E$) during the pre KORea-US Air Quality Study (KORUS-AQ) campaign using a couple of Muliti Angle Absorption Photometers (MAAP). BC mass concentrations were presented as $2.14{\pm}1.06{\mu}g/m^3$ and $0.94{\pm}0.60{\mu}g/m^3$ at KIST site (Seoul) and KOREATECH site (Cheonan), respectively. BC mass concentrations measured at KIST and KOREATECH sites from 22:00 on May 22 to 12:00 on May 23, 2015 showed 80% and 72% higher than average BC mass concentrations measured during campaign period, respectively. It indicates both sites could be influenced by a remote source. Similar patterns of BC concentrations between two sites from 20:00 to 24:00 on June 6, 2015 implies that the BC could be transported into both sites and then be stagnant inside the Korean Peninsula. Diurnal variation of BC in weekdays and weekends were also presented for the KIST and KOREATECH sites. Morning rush hour peak was observed at KIST site located in metropolitan area though no distinct morning rush hour peak was not observed at KOREATECH site located in a suburban area. This study revealed transport pathways of BC near the Korean Peninsula using back-trajectory analysis of BC measured both in a metropolitan area and in a suburban area.

• 한국육종학회지
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• 제43권5호
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• pp.360-367
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• 2011

Beta-carotene producing transformants were produced in the background of 'Nagdongbyeo', a Japonica rice cultivar. Introgression of the carotenoid locus in the transformant, PAC4-2 into the elite cultivar 'Ilpumbyeo' was started. To initiate a backcrossing program, we surveyed 220 SSR markers and found that 38% of them were polymorphic between 'Ilpumbyeo' as a recurrent parent and the PAC4-2 as a recipient parent. The selection strategy comprising foreground and background selection was employed. First, foreground selection was practiced in $BC_1$, $BC_2$, and $BC_3$ generations using the transgene specific PCR-based marker in addition to visual scoring of the seed color. Marker-based background selection combined with phenotypic selection was employed from $BC_3F_2$ to $BC_3F_4$ generations. Blast search indicated that the transgene PAC4-2 was located between SSR markers, RM6 and RM482. 240 $BC_3F_3$ and 63 $BC_3F_4$ lines were evaluated for four agronomic traits including days to heading. Most of the lines were similar to Ilpumbyeo in agronomic traits evaluated. The percentage of PAC4-2 genome ranged from 4% to 21% with a mean of 12.5%, which was higher than the expected for an unselected $BC_3$ backcross population. This could be explained by the fact that two genes for beta-carotene and the stripe virus resistance were targeted in this study. We selected 10 representative $BC_3F_5$ lines from 63 $BC_3F_4$ lines based on agronomic traits and carotenoids content. The selection strategy would be appropriate for the introgression of beta-carotene gene in a breeding program.

• Tribology and Lubricants
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• 제27권2호
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• pp.65-70
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• 2011

The power servo cylinder for driving accurately turbine stop valve of an atomic power plant is necessary to do turn-over owing to a leakage of oil and a structure problem, especially, it of a power plant be in demand a high quality standard depends entirely on import. There are much problem that the AlBC be to used as a material of piston head in cylinder are caused by wear. Therefore, it is necessary to examine friction characteristics of it. In this study, wear test experiments was carried out with AlBC and SCM440, using reciprocating friction tester of pin on disk. This result was shown that the wear mechanism of AlBC on working condition is adhesive wear and the maximum temperature of infra redray thermal image of frictional surface show over 2 mm from contact surface of pin and disk.

• 한국육종학회지
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• 제41권4호
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• pp.463-467
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• 2009

Allium 속 근연종인 파와 양파간 종간교잡을 이용하여 양파로부터 새로운 형질을 도입하는 과정에서 유래되는 종간교잡 F1과 여교잡 세대들의 게놈크기의 변화를 flow cytometry를 이용하여 측정한 결과 다음과 같은 결과를 얻었다. 1. 양파와 파의 종간교잡 F1의 식물학적 특성은 양친의 중간형을 보였으나 여교잡이 진전됨에 따라 반복친인 파의 표현형이 우세하였다. flow cytometry를 이용하여 2C nuclear DNA content을 측정한 결과 $F_1$은 양친에 비해 오히려 증가하였으나 여교잡이 진행됨에 따라 급속히 감소하여 $BC_2F_1$에서는 반복친과 비슷한 수준으로 감소하였다. 여교잡세대의 자식인 $BC_1F_2$은 반복친과 비슷한 $23.1{\pm}1.0pg$으로 측정되었으나 $BC_2F_2$는 $22.9{\pm}0.4pg$으로 반복친의 2C nuclear DNA content인 $23.2{\pm}0.2pg$ 보다 오히려 감소하였다.