• Journal of Environmental Health Sciences
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• v.27 no.3
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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.

• Journal of Fashion Business
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• v.21 no.4
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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.

• Special Issue of the Society of Naval Architects of Korea
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• 2015.09a
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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.

• Journal of Korean Library and Information Science Society
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• v.42 no.2
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• pp.237-255
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• 2011

This study is to find new methods in describing material type as content type and carrier type for the improvement of OPAC retrieval and the embodiment of work and expression of FRBR. It is hard to describe type vocabulary in cataloging because division of content and carrier taxonomy in KCR4 and KORMARC is not distinct. This study is to review the characteristics of material type list in RDA and ISBD(2010), and to examine the various type vocabulary and description methods of videorecording, soundrecording, and cartographic by retrieving KERIS DB. As a result, there is no consistency in applying type vocabulary between KCR4 and KORMARC. Also, libraries use the mix of content and carrier or detailed carrier vocabulary for local use. Therefore, it is need to define the function of GMD as content type, to expand and correct content and carrier vocabulary, and to express both content and carrier type in citation and detailed display. This study will contribute to embody the expression of FRBR.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.3
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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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• v.22 no.1
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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.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.1
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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.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.2
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• pp.125-134
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• 2015

Spherical type LNG carrier has many advantages, but has a demerit it is more expensive than membrane type one. Therefore, when calculating the initial estimate of spherical type LNG carrier, high accuracy calculation of tank weight has to be carried out. In this study the simplified analysis method which is able to calculate stresses of all the tank zones is established and has special feature to deal with static and dynamic loading. In order to verify the established method, the design results obtained through the method in this study have been compared with those of existing ship obtained from finite element analysis. As a result, the usability of simplified analysis method has been confirmed.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.4
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• pp.986-996
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• 1994

Insulation system of LNG carrier has made important roles such as maintaining a proper Boil off Ratio(BOR) for the cargo and avoiding the excessive low temperature of the adjacent inner hull beyond the permissible limit. At the same time, safety and economy of the LNG transportation by the ship are connected with the performance of the insulation system. Also, thermal insulation system of LNG carrier is one of the most advanced technique with the structure analysis of tank, welding and assembling. In this study a computer program is developed to calculate the hull temperature distribution and BOR, which are important factors in thermal design for the Moss Rosenberg Verft spherical tank type LNG carrier. Detailed results for hhull temperature distribution close to LNG tank, BOR and the thickness effect of insulation material are reported in this paper in the range of standare design sea condition.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.05a
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• pp.80-85
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• 2002

The progressive die for U-bending production part is a very specific division. This study reveals the Sheet metal forming process with multi-forming die by Center Carrier type feeding system. Through the FEM simulation by DEFORM it was accepted to u-bending process as the first performance to design in strip process layout design. The next process of die development was studied according to sequence of die development.