• Journal of Nutrition and Health
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• 제28권8호
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• pp.782-790
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• 1995

The longitudinal changes in protein secretion from 27 lactating women(primiparae = 10, multiparae=17) and protein intake of infants have been studied from 0.5 to 6 months postpartum in Chungju and Anseong area. The protein contents o breast milk in primiparae appeared significantly higher than in multipaae at 0.5 and 1 month postpartum. The protein secretion of primiparae and multiparae was not significantly different. In breast-feeding period, there was a tendency that protein secretion from 0.5 to 2 months postpartum was higher than thereafter. Average protein intake of boys from milk from 0.5 to 6 months postpartum was significantly higher than that of girls(p<0.05), because volume of milk intake of boys was much more than that of girls. In the amount of protein intake per infant weight, there was no significant difference between boys and girls. Protein intakes per infant weight decreased during lactation. Mean energy consumption of lactating women was 2,327㎉/day, which was 93.1% of recommended energy allowance for Koreans. Mean dietary protein consumption of lactating women was 81g/day, which was 101.3% of recemmended protein allowance for Koreans. Energy ratio of carbohydrate : protein : lipid was appeared to 68.8 : 13.9 : 17.3.

• 한국전자통신학회논문지
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• 제11권1호
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• pp.9-16
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• 2016

IEEE 802.15.4 LR-WPAN에서 대부분의 디바이스는 배터리에 의존해 동작하기 때문에 효율적인 에너지 소비기능을 갖추도록 설계되어야 한다. 본 논문은 LR-WPAN에서 에너지 절약을 위한 두 개의 알고리즘, DDC(Dynamic Duty Cycle)와 DBT(: Dynamic Beacon Tracking)를 제안한다. DDC 알고리즘은 채널 상태에 따라 듀티 사이클을 동적으로 조정한다. DBT 알고리즘은 트래픽 조건에 따라 비콘 트래킹 모드를 적응적으로 제어한다. 또한, DDC와 DBT 알고리즘을 결합함으로써 프레임 전달률과 평균 지연 시간을 만족할 만한 수준으로 유지하면서 광범위한 입력 부하에 대해 효과적으로 에너지를 절약할 수 있다.

• 천문학회보
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• 제43권1호
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• pp.35.1-35.1
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• 2018

Shock waves have been observed in the outskirts of galaxy clusters. They are commonly interpreted as being driven by mergers of sub-clumps, so are called "merger shocks". We here report a study of the properties of merger shocks in merging galaxy clusters with cosmological hydrodynamic simulations. As a representative case, we describe the case where sub-clusters with mass ratio ~ 2 go through an almost head-on, binary-like merger. Because of the turbulent nature of hierarchical clustering, shock surfaces are not uniform, but composed of parts with different Mach numbers. As merger shocks expand from the core to the outskirts, the average Mach number, < $M_s$ >, increases. The shocks propagating along the merger axis could be observed as X-ray shocks and/or radio relics. The kinetic energy through the shocks peaks at ~ 1 Gyr after shock launching, or at ~ 1 - 2 Mpc from the core. The most energetic shocks are found to have the kinetic-energy weighted Mach number, < $M_s$ > $_{\phi}{\simeq}2-3$, and the CR-energy weighted Mach number, < $M_s$ > $_{CR}{\simeq}3-4$. We then discuss the observational implications of our results.

• 조명전기설비학회논문지
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• 제28권8호
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• pp.106-112
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• 2014

This paper presents the analysis of connected operation of photo voltaic source and Li energy storage system. The micro-grid has been installed and operated for several years at the campus of USF and has been a role of test bed. Photo voltaic source has been strongly influenced by the location, weather and climate of a installed area and Li battery is connected directly to the photo voltaic source to compensate for the limitations. The Li battery is operated to supply power output to the grid by the charging or discharging mode based on the average power output of the PV source which is calculated from monitored data for several years. The load of the PV and Li battery system is operated as a severe loading condition and the operating characteristics of PV source and Li battery are analyzed in detail. In connected operations of PV and Li battery to power system, the PV and Li battery is operated to supply constant power during only day time or peak time to increase load shedding ratio and efficient usage of generation sources in power system.

• 대한화학회지
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• 제33권5호
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• pp.459-467
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• 1989

계면활성제가 수용액 중에 용해되면 용액내에서 micelle이라는 응집체를 형성하며, micelle은 그 내부에 oil를 용해시켜 swollen micelle을 형성하게 된다. 실제로 물-oil-계면활성계의 상평형도상에서 micelle과 swollen micelle은 동일영역에 존재하게 되나 일반적으로 micelle과 swollen micelle의 형성에 관해서는 서로 다른 관점으로 취급되어 왔다. 본 연구에서는 이러한 계면활성제 응집체의 형성에 관한 일관된 열역학적 모델을 제시하고자 한다. 모든 경우에 저농도 영역에서 이상용액 이론을 적용하였으며, micelle 형성에너지는 소수성 작용에너지와 계면에서의 표면에너지의 합으로 표시하였다. 이론식으로부터 임계마이셀농도, 평균응집분자수, 용해비 등을 예측하였으며 실험관측치와 비교하였다.

• 상하수도학회지
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• 제27권3호
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• pp.339-349
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• 2013

Biological treatment of RO concentrate from wastewater reuse process is known to be very difficult due to its high concentration of non-degradable organics and salt ions such as chloride, nitrate and phosphate. In this research, the treatment performance of MBR was examined using RO concentrate mixed with raw wastewater as the influent of MBR. Addition of PAC (powdered activated carbon) to MBR was also evaluated in order to enhance the treatment performance and stability. The performance of MBR for treating only RO concentrate decreased gradually although external carbon source was added. The average removal performance of MBR with and without PAC decreased from 99.1 %(98.8 %) to 94.9 %(91.4 %) for COD, 81.3 %(80.3 %) to 42.0 %(41.9 %) for T-N and 57.3(55.0 %) to 30.0 %(21.0 %) for T-P with the increase of RO concentrate mixing rate of 0 % to 20 % in the feed water. Addition of PAC showed positive effect on the performance of MBR for the removal of COD and phosphorus in case that the ratio of RO concentrate to feed water increased.

• 신재생에너지
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• 제8권3호
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• pp.23-29
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• 2012

LCOE of 11 Korean PV projects, total capacity of 44 MW, were calculated for each project being larger than 1 MW respectively. 9 out of 11 projects were constructed in 2008 under FIT scheme revealed that average LCOE is 600 Korean Won per kilowatt-hour and it becomes reduced to 348 Korean Won per kilowatt-hour for 2 projects that are constructed under RPS scheme in 2012. During the period between 2008 and 2012, installation cost per megawatt became 55% of 2008 value with operation and maintenance cost lowered to 80% while LCOE became only 58% due to reduced project size and lower irradiation for later projects. However, it is found that the ratio of LCOE / unit installation cost looks relatively constant, so that it can be used as an auxiliary parameter to gauge learning effect of BOS portion of a PV project.

• 한국음향학회지
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• 제29권1호
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• pp.62-68
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• 2010

본 논문에서는 기존 마스킹 임계값 적응 방식을 개선하여 저전송률 오디오 부호화에서 음성 신호에 대한 성능을 향상시킨다. 포먼트 영역 검색 이후, 각 포먼트 영역의 평균 에너지와 해당 서브밴드의 에너지 비율을 이용하여 마스킹 임계값을 변화시킨다. 상대적으로 에너지가 큰 밴드에 대해서는 더 많은 양자화 노이즈가 허용되는 반면, 청각적으로 민감한 스펙트럴 밸리에서는 비트 할당을 높여 양자화 에러를 좀 더 줄인다. 이는 음성 부호화에서 널리 사용되는 지각 가중(perceptual weighting) 개념을 반영한 것이다. 객관적 음질 평가 결과, 제안한 알고리즘이 기존 방식에 비해 음성 신호에 대한 성능을 향상시킨다는 것을 확인하였다.

• 한국환경과학회지
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• 제27권10호
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• pp.925-931
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• 2018

The characteristics of $PM_{10}$, $PM_{2.5}$ and Ratio($PM_{2.5}/PM_{10}$) of 11 urban air monitoring stations in Gyeongnam were analyzed for the last 3 years('15~'17). The average of the all stations was $PM_{10}\;45{\mu}g/m^3$, $PM_{2.5}\;24{\mu}g/m^3$ and Ratio 0.54, and annual reduction rates were $PM_{10}-2.9%$, $PM_{2.5}-2.7%$ and Ratio -1.2%, respectively. The seasonal characteristics of $PM_{10}$ were spring $54{\mu}g/m^3$ > winter $48{\mu}g/m^3$ > summer/autumn $40{\mu}g/m^3$, $PM_{2.5}$ were spring/winter $26{\mu}g/m^3$ > summer 23 > autumn $22{\mu}g/m^3$ and Ratio were summer 0.56 > winter 0.55 > autumn 0.54 > spring 0.51, respectively. The hourly characteristics of $PM_{10}$ were $11{\mu}g/m^3$ higher than 09:00~12:00 at 03:00~06:00, $PM_{2.5}$ were $6{\mu}g/m^3$ higher than 09:00~12:00 at 17:00~18:00 and Ratio were 0.07 higher than 04:00~06:00 at 19:00. By site, the highest concentration of $PM_{10}$ was YJ site $53{\mu}g/m^3$ and $PM_{2.5}$ was HW site $28{\mu}g/m^3$. And Ratio at HD site showed the largest reduction from '15 0.62 to '17 0.52.

• Journal of Nutrition and Health
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• 제40권2호
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• pp.182-190
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• 2007

The purpose of this study is to evaluate dietary quality of Korea Antarctic expedition by menu analysis. Basic menu pattern, intake of dish and dish group, DDS (dietary diversity score), daily nutrients supply, and NAR (nutrient adequacy ratio) & MAR (mean adequacy ratio) were analyzed using 1 year menu list for the 10th Korea Antarctic expedition. Most frequently served basic menu patterns were ${\ulcorner}$Rice + Soup + 2 Side dish + Kimchi (53.5%)${\lrcorner}$ and ${\ulcorner}$Rice + Stew + 2 Side dish + Kimchi (13.4%)${\lrcorner}$. In the analysis of dish group, excluding Rice and Kimchi, ${\ulcorner}$Grilled foods${\lrcorner}$ and ${\ulcorner}$Pan-fried foods${\lrcorner}$ were served more than 25% per month. Most frequently served dishes were "pan-fried rolled egg", "grilled seaweed", "kimchi soup", "fruits cocktail, canned" and "salt-fermented squid". The kinds of served dishes were very restrictive. The average score of DDS showed 2.88 for summer and 2.97 for winter. Dairy group was almost not served. Fruit & Vegetable groups were also served a little as canned product. The energy ratio of Carbohydrate : Fat : Protein was 56.5 : 23.9 : 19.2, and 56.9 : 24.5 : 18.3, for summer and winter, respectively. Both seasons had higher ratio of carbohydrate and lower ratio of fat compared to the recommended ratio (44 : 40 : 16) in polar area. Ca : P ratio was very poor, 0.40 in both seasons. NAR scores of Ca, vitamin A, vitamin $B_2$ and vitamin C were also very low, ranged from 0.6 to 0.7. Consequently, a well-planned menu supplying adequate amount of dairy, fruit and vegetable is necessarily required including Ca, vitamin D, vitamin A, vitamin $B_2$ and vitamin C intake, and some nutritionally well-educated members are urgently needed to join in the expedition.