• 한국유기농업학회지
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• 제25권2호
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• pp.461-473
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• 2017

Total mixed ration (TMR) including concentrate diet and roughage together have been used for the ruminant animal. Relatively high concentrations of moisture and water soluble carbohydrate are representative feature of TMR. Those moisture and water can also provide a niche for bacterial growth. Therefore, a possible fermentation of TMR induced by micro-organism is generally accepted. The present study hypothesized that different lactic acid bacteria could alter fermentation of TMR and subsequently rumen fermentation. Three lactic acid bacteria, Lactobacillus paracasei (A), L. plantarum (B) and L. parabuchneri (C), were employed and 7 treatments under full factorial design were compared with control without inoculation. TMR for dairy cow was used. Significant alterations by treatments were detected at lactic acid and butyric acid contents in TMR (p<0.05). Treatment AC (mixture of A and C) and BC (mixture of B and C) showed great lactate production. Great butyrate production was found at treatment C. At in vitro rumen fermentation, treatments B, C and AB (mixture of A and B) showed significantly great total gas production (p<0.05). All treatments except treatments B and AB, showed less dry matter digestibility, significantly (p<0.05). Total volatile fatty acid production at treatment AC was significantly greater than others (p<0.05). In individual volatile fatty acid production, treatment AB and AC showed great acetate and propionate productions, significantly (p<0.05). This study investigated correlation between organic acid production in TMR and rumen volatile fatty acid production. And it was found that butyric acid in TMR had significant negative correlation with acetate, propionate, total volatile fatty acid, AP ratio and dry matter digestibility.

• 한국가금학회지
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• 제38권1호
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• pp.21-28
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• 2011

택사와 겨우살이가 육계의 생산성 및 면역성에 미치는 영향을 규명하기 위하여 실시하였으며, 공시동물은 육계 초생 추 140수를 4처리구 5반복 반복당 7수씩 공시하여 5주간 사양 시험을 실시하였다. 처리구는 무항생제 사료 급여구를 대조구로 하고 항생제 처리구(기초 사료+ OTC 0.05%), 택사 처리구(기초 사료+ 택사 0.5%) 및 겨우살이 처리구(기초 사료+겨우살이 0.5%)로 하였다. 증체량과 사료 섭취량은 처리구간에 유의적인 차이는 없었으며, 사료 요구율은 택사 처리구가 겨우살이 및 기타 처리구에 비해 유의적으로 높았다(P<0.05). 도체의 지방산 분석에서${\omega}$3 및${\omega}$6 계열의지방산인linolenic acid, ${\alpha}$-linolenic acid 및 arachidonic acid의 함량은 겨우살이 및 택사 급여구에서 항생제 처리구에 비해 비교적 높았으며, SFA, USFA 및 USFA/SFA의 함량은 처리구 간에 유의적인 차이는 없었다. 혈중의 IgG의 농도는 처리구 간에 유의적인 차이는 없었으나, 택사와 겨우살이 처리구가 높았으며, IL2의 농도는 택사와 겨우살이 처리구에서 유의적으로 높았다(P<0.05). IL6는 검출되지 않았다. 겨우살이 첨가구에서 GOT, GPT 및 T-billirubin이 유의적으로 높게 검출됨으로써 간장의 손상을 일으킬 수 있는 것으로 판단되었다(P<0.05). 결론적으로 육계 사료에 택사 0.5%와 겨우살이 0.5% 첨가 급여는 생산성은 항생제 첨가와 유사한 효과가 있고 면역성은 증가시켰다. 따라서 항생제 대체제로 사용 가능성이 높은 것으로 사료된다.

• 제어로봇시스템학회논문지
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• 제21권4호
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• pp.385-390
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• 2015

Quay cranes are considered core equipment for container terminal operation. However, unmanned operation systems have not as yet been announced due to the technological difficulties of implementation. In this paper, we developed a wireless controller to control a quay crane simulator remotely and conducted its performance test, a first step toward unmanned operation of quay cranes. The communication delay of a developed wireless controller was about 9.4ms on average while that of existing wired controllers was about 5.6ms. The same functions were implemented and tested on a smart phone where the average communication delay was 7.3ms. In addition, to apply the developed system into a real environment, we proposed a network architecture based on IEEE 802.11ac and carried out its performance evaluation. When the distance between two nodes was 50m apart, the throughputs of the TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) were 57Mbps and 189Mbps, respectively. The communication delay of the control data was 9.1ms through the TCP channel. These results reveal the proper working of remote quay crane operation if we adopt the IEEE 802.11ac network.

• Journal of Power Electronics
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• 제7권2호
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• pp.97-108
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• 2007

This paper describes simple control structures for a vector controlled stand-alone induction generator (IG) for use under variable speeds. Different control principles, indirect vector control and deadbeat current control, are developed for a voltage source PWM converter and the three-phase variable speed squirrel-cage IG to regulate DC-link and generator voltages with a newly designed phase locked loop circuit. The required reactive power for the variable speed IG is supplied by means of a PWM converter and a capacitor bank to buildup the voltage of the IG without the need for a battery, to reduce the rating of the PWM converter while using only three sensors and to eliminate the harmonics generated by the PWM converter. These proposed schemes can be used efficiently for variable speed wind energy conversion systems. The measurements of the IG systems at various speeds and loads are given and show that these systems are capable of good AC and DC voltage regulation.

• Journal of Power Electronics
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• 제7권2호
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• pp.109-117
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• 2007

In this paper, a novel proposal for a utility-interactive three-phase soft commutation sinewave PWM power conditioner with an auxiliary active resonant DC-link snubber is developed for fuel cell and solar power generation systems. The prototype of this power conditioner consists of a PWM boost chopper cascaded three-phase power conditioner, a single two-switch auxiliary resonant DC-link snubber with two electrolytic capacitors incorporated into one leg of a three-phase V-connection inverter and a three-phase AC power source. The proposed cost-effective utility-interactive power conditioner implements a unique design and control system with a high-frequency soft switching sinewave PWM scheme for all system switches. The operating performance of the 10 kW experimental setup including waveform quality, EMI/RFI noises and actual efficiency characteristics of the proposed power conditioner are demonstrated on the basis of the measured data.

• 대한의생명과학회지
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• 제16권4호
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• pp.381-385
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• 2010

Indole-3-carbinol (I3C), one of naturally occurring main components in cauliflower vegetables, is supposed to have a chemopreventive potential in experimental animals and humans. This study was investigated to examine chemopreventive effect of I3C on colon carcinogenesis induced by azoxymethane (AOM) using C57BL/6J mice. Mice were divided into three groups (10 or 9 mice/group). All mice were subcutaneously injected with AOM (5 mg/kg body weight, four times at weekly interval). After AOM treatment, animals of group 1 were fed by AIN-76A pellets as a basal diet. Animals of groups 2 and 3 were given I3C containing diets (100 and 300 ppm in diets, respectively) for 6 weeks until sacrifice. All mice were sacrificed at week 10 and the aberrant crypt foci (ACF) of the colonic mucosa were assessed after staining with methylene blue. Total numbers of ACF/colon in group 2 ($10.1{\pm}5.1$) or group 3 ($10.6{\pm}5.3$) were decreased compared to the values of group 1 ($14.4{\pm}10.2$). Among numbers of ACF formation, 5, 7, 8 and 10 ACF in group 2 and 3 were greatly different those of group 1. Total numbers of aberrant crypts (AC)/colon of group 2 ($20.1{\pm}10.1$) or group 3 ($22.0{\pm}10.9$) were decreased compared to the value of group 1 ($33.7{\pm}24.7$). Taken together, it suggests that I3C treatment may retard mouse colon carcinogenesis even after administration of AOM.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.1833-1836
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• 2012

Objective: Promoter methylation, which can be regulated by MTHFR activity, is associated with silencing of genes. In this study we evaluated the methylation status (type) of the BRCA2 promoter in ovarian cancer patients carrying different genotypes of the MTHFR gene (A or C polymorphisms at position 1298). Methods: The methylation type of the BRCA2 promoter was evaluated using bisulfate-modified DNA in methylation-specific PCR and the MTHFRa1278c polymorphism was assessed by PCR-RFLP. Results: Analysis of the BRCA2 promoter methylation type of cases showed that 7 out of 60 cases (11.7%) were methylated while the remaining 53 (88.3%) were unmethylated. In methylated cases, one out of the 7 cases had a CC genotype and the remaining 6 methylated cases had an AC genotype. The AA genotype was absent. In unmethylated cases, 34, 18, and one out of these had AC, AA and CC genotype, respectively. Conclusion: There was no significant relationship between the methylation types of the BRCA2 promoter in different genotypes of MTHFRa1298c polymorphism in ovarian cancer; p=0.255. There was no significant relation between the methylation types of the BRCA2 promoter in different genotypes of the MTHFRa1298c polymorphism in ovarian cancer.

• Advances in Energy Research
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• 제4권1호
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• pp.1-28
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• 2016

A grid-connected photovoltaic (PV) system comprised of multicrystalline silicon (mc-Si) modules was installed in a cold climate region in the U.S. This roof-mounted stationary PV system is a real-world application of PV for building energy generation in International Energy Conservation Code (IECC) Climate Zone 5 (and possibly similar climate zones such as 6, 7 and 8), and it served the purposes of research, demonstration, and education. The importance of this work is highlighted by the fact that there has been less emphasis on solar PV system in this region of the U.S. because of climate and latitude challenges. The system is equipped with an extensive data acquisition system capable of collecting performance and meteorological data while visually displaying real-time and historical data through an interactive online interface. Experimental data was collected and analyzed for the system over a one-year period with the focus of the study being on measurements of power production, energy generation, and efficiency. The annual average daily solar insolation incident upon the array was found to be $4.37kWh/m^2$. During the first year of operation, the PV system provided 5,801 kWh (1,264 kWh/kWp) of usable AC electrical energy, and it was found to operate at an annual average conversion efficiency and PR of 10.6 percent and 0.79, respectively. The annual average DC to AC conversion efficiency of the inverter was found to be 94 percent.

• 전력전자학회논문지
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• 제23권2호
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• pp.101-105
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• 2018

Shortage of electric power occurs frequently along with increased electric power demand. ESS is a precaution to solve this issue. Household ESS has a capacity of approximately 3 kW/7 kWh. Household ESS batteries are typically designed with nominal voltages between 40 and 50 V. To connect household ESS with a 220 V AC system, low battery voltages in power conditioning system (PCS) should be boosted. To boost low battery voltage and match it with AC grid voltage, the use of a transformer for a commercial frequency can be considered. To attenuate switching harmonics of the household single-phase ESS-PCS, LC filter can be installed in two positions: on the primary side or on the secondary side of a transformer. A method has been used generally in single-phase inverters for the ESS-PCS. In another method, however, the output efficiency of the ESS-PCS may be decreased. Parasitic components of the transformer can affect voltage losses, when the square wave with the switching frequency in the ESS-PCS is passed through the transformer windings. In this work, the characteristics of the transformer according to the position of an LC filter are investigated for household single-phase ESS-PCS.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1526-1528
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• 1999

In this papaer, 7-segment was implemented using AC powder EL. ZnS:Cu and $BaTiO_3$ was used as a phosphor and dielectric respectively. The preparation of phosphor and dielectic layer was performed with screen printing. The implemented system of 7-segment was divided as following; EL display. driving circuit. software for driving. The properties of fabricated devices was measured with EL spectrum. brightness and J-V.