• 한국환경보건학회지
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• 제27권3호
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• pp.27-34
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• 2001

This paper discussed the shape effect of ceramic support carrier in order to facilitate biomass immobilization. The shape of ceramic support carrier was modified hollow pipe type into hollow gear type. After seeding, microorganisms were attached in crevices where protection from shear forces or surfaces where easy to contact with support carrier surface. In case of hollow gear type carrier, initial attachment rate was faster than that of hollow pipe type and obtained thick biofilm. Synthetic wastewater(COD:75~880 mg/L, organic loading rate:0.36~4.22 kgCOD/㎥.d) was treated aerobic fixed bed biofilm reactor where 100% of the volume was filled with the ceramic carrier. COD removal efficiency of reactor filled with gear type support carrier was a little high withing 70 days, and then showed similar removal efficiency. It was found that highly loaded operation with up to 4.22 kgCOD/㎥.d was possible in both reactor. Total biomass amounts of pipe type was higher than gear type, however, attached biomass of gear type was higher than that of pipe type.

• 패션비즈니스
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• 제21권4호
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• pp.105-115
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• 2017

Continuous lifting and carrying of babies constitutes a serious physical burden, leading to issues such as muscle fatigue and pain in child-care workers. However, there is a lack of research on the pressure and subjective comfort of baby carriers that are commercially available in the market. Therefore, this study was intended to determine the most comfortable and least burdensome type of baby carrier. This was done by analyzing muscle activity and pressure when subjects carried babies using three types of baby carriers. The types of baby carriers evaluated included a 'baby carrier of thin shoulder straps without back support band (X-type)', a 'baby carrier with a back-support band and without a hip sheet (H-type)', and a 'baby carrier with back support band and hip support (H-hip type). The subjective comfort of subjects wearing each type of baby carrier was investigated and compared to the objectively measured data. As a result, the X-type baby carrier showed the heaviest pressure on the shoulders and the subjective comfort was found to not be good. On the waist region, the H-type and H-hip type baby carriers showed significantly less muscle activation than the X-type baby carrier. However, subjects showed a stronger preference for the X-type baby carrier on the waist region, despite greater muscle activation. This appears to be because although the back-support band disperses the weight and thus improves physiological comfort; the wearers feel cramped and thus, lower their psychological comfort.

• 대한조선학회 특별논문집
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• 대한조선학회 2015년도 특별논문집
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• pp.79-84
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• 2015

A BC-B type bulk carrier is rarely built, so the structural characteristics is not reported and familiar so far. The biggest difference between BC-B and BC-A type vessel is applying alternate cargo loading, which density is over $1.0ton/m^3$. In this paper, 150K DWT class BC-B type bulk carrier is calculated and compared with BC-A type vessel, which has same condition such as main dimension and deadweight, about prescriptive rule and FEA based on CSR. And aspect ratio of target vessel is smaller than typical capsize bulk carrier, so 150K and 180K bulk carrier, which applied BC-A type, are also compared to find feature of wide beam vessel.

• 한국도서관정보학회지
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• 제42권2호
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• pp.237-255
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• 2011

본 연구는 이용자의 온라인목록 검색 향상과 FRBR 저작 및 표현형을 구현하기 위해 내용과 용기로 자원유형을 기술하는 방안을 모색하고자 한다. KCR4, 통합KORMARC의 자원유형 리스트의 내용과 용기의 구분이 명확하지 않아 GMD 및 SMD 자원유형 기술 시 어려움을 주고 있다. 이를 위해 본고는 RDA와 ISBD(2010)의 자원유형리스트의 특징을 파악하고, KERIS 종합목록을 대상으로 비디오녹화자료, 녹음자료, 지도자료의 다양한 용어 사용과 기술 현황을 분석하였다. 분석결과 GMD, SMD 용어리스트에 일관성이 부족하였으며, 도서관에서는 내용유형과 용기 유형 용어를 자관에 맞게 혼합하여 적용하였다. 새로운 방안으로 자원의 내용유형 기술의 필요성, 내용유형 및 용기유형 용어의 정립, 디스플레이방식을 제안하였다. 본 연구를 통해 앞으로 FRBR 개념모델을 구현할 수 있는 자원유형 기술에 새로운 방안을 마련할 수 있을 것이다.

• 산업경영시스템학회지
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• 제45권3호
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• pp.49-56
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• 2022

ROK Navy intends to secure the Korean-type aircraft carrier in order to effectively prepare for various future security threats. In general, the Korean national competency is considered to be at the level of having an aircraft carrier, but it is unclear what scale aircraft carrier would be appropriate. In this study, the efficiency was evaluated through the relative comparison between national competency(national power, economic power) and the scale of aircraft carriers, and the optimal scale of the Korean-type aircraft carrier that could be acquired was presented. A DEA(Data Envelopment Analysis) model was applied to aircraft carriers(19 aircraft carriers in 11 countries) currently in operation and scheduled to be possessed in the world. As input variables, CINC(Composite Index of National Capability) and GDP(Gross Domestic Product), which are the most widely used as indicators of national and economic power, and as output variables, the full-load displacement, length, and width of aircraft carriers were selected. ARIMA(short-term within 5 years) and simple regression(long-term over 5 years) were used to estimate the future national competency of each country at the time of aircraft carriers acquisition. The relative efficiency score of the Korean-type aircraft carrier currently being evaluated is 1.062, and it was evaluated as small-scale aircraft carrier compared to the national competency. Based on Korean national competency, the optimal scale of the Korean-type aircraft carrier calculated by aggregating benchmark groups, is 58,308.1 tons of full-load displacement, 279.4m in length, and 68.3m in width.

• Journal of Advanced Marine Engineering and Technology
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• 제18권2호
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• pp.75-82
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• 1994

The existence of peroodic impulse noises in distribution line carrier (DLC) communication system is known to be the most serious obstacle for improving DLC communication quality in reliability and capacity. From the spectral points, impulse noises can be divided into baseband type and modulation type the noise width of whichs are much different each other. With each nose type, this study presents the basic characteristics in relation to what they originate from and how their spectrum properties are revealed. The baseband type impulse noise is normally caused from thyristor circuit running with low switching speed and the modulation type noise from the circuit of switching power supply. The base wave of modulation noise is shown to be the pulsuatic charging current to primary condenser in switching power circuit. The study result indicates also that placing the DLC carrier frequency away the band predominated by modulated noise especially from RCC type switching power circuit is very important in DLC design.

• Journal of Advanced Marine Engineering and Technology
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• 제22권1호
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• pp.28-34
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• 1998

This paper introduced the thermal characteristics of Moss Rosenberg Verft spherical tank type LNG Carrier. Especially described the temperature variation during cooling down condition. It is not easy task to calculate the temperature variation because of unsteady state condition. In this paper, computer simulation program is developed by using a Tomas Algorithm on unsteady state condition and compared with calculation results and experimental results on existing LNG Carrier voyage.

• 한국전기전자재료학회논문지
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• 제15권1호
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• pp.1-6
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• 2002

The hot carried degradation in a metal oxide semiconductor device has been one of the most serious concerns for MOS-ULSI. In this paper, three types of LDD(lightly doped drain) structure for suppression of hot carried degradation, such as decreasing of performance due to spacer-induced degradation and increase of series resistance will be investigated. in this study, LDD-nMOSFETs used had three different drain structure, (1) conventional surface type LDD(SL), (2) Buried type LDD(BL), (3) Surface implantation type LDD(SI). As experimental results, the surface implantation the LDD structure showed that improved hot carrier lifetime to comparison with conventional surface and buried type LDD structures.

• 한국기계가공학회지
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• 제15권4호
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• pp.67-72
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• 2016

Planetary gear sets are widely used in power transmission components, which have high efficiency and good durability. Their most important design parameter is the load-sharing characteristics among several planetary gears. In this study, the load sharing of planetary gears was analyzed according to the carrier pinhole position error of planetary gear sets. The loads acting on planetary gears varied with the pinhole position error of the carrier, and the load sharing of planetary gears improved as the input load increased. In addition, the load of the planetary gear with a carrier pinhole position error was relatively higher than that of other planetary gears without carrier pinhole position errors. This trend appeared more clearly in the non-floating-type carrier than the floating-type carrier.

• 정보관리학회지
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• 제33권1호
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• pp.33-52
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• 2016

본 연구는 GMD를 대체하는 RDA 자원유형인 내용유형, 매체유형, 수록매체유형의 디스플레이를 위한 고려사항을 모색하고자 한다. 연구방법으로는 문헌연구, 사례조사, 설문조사를 이용하였다. RDA 자원유형의 디스플레이 방안으로 첫째, RDA 자원유형을 디스플레이하기 위해 내용유형과 수록매체유형을 결합하는 것을 제안하였다. 둘째, RDA 내용유형과 수록매체유형을 아이콘화하는 알고리즘으로 내용유형을 나타내는 이미지와 수록매체유형 용어를 결합하는 방안과 내용유형과 수록매체유형을 모두 이미지로 표현하고 각 이미지에 해당하는 용어를 포함시키는 방안을 제안하였다. 셋째, 복합자원의 자원유형 디스플레이를 위해 필드링크와 순서를 나타내는 서브필드를 활용하여 내용유형, 수록매체유형이 세트로 유지될 수 있도록 제안하였다. 넷째, 간략화면에서 자원유형을 나타내는 아이콘은 자원이 디스플레이되는 왼쪽 상단에 두고, 상세화면에서는 자원유형을 기술사항 내에 배치하는 것을 제안하였다. 다섯째, 표출어로 '포맷'이라는 표현을 사용할 것을 제안하였다. 본 연구는 RDA 자원유형의 디스플레이를 계획할 때 고려사항을 제시하였으므로 도서관에서 실질적인 RDA 디스플레이 방안 마련에 활용할 수 있을 것이다.