• International Journal of Highway Engineering
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• v.5 no.2 s.16
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• pp.15-24
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• 2003

The performance of waterproofing system (WPS) is known to be a function of many complex interaction of material factors, design details, and the quality of construction, but it is mainly determined by the bond strength, which is measured by tensile adhesive strength (TAS) test. to the concrete bridge deck. In this research, eight waterproofing membranes were selected from commercial market and the tensile adhesive characteristics of the WPS on concrete bridge deck were investigated in view of various factor in asphalt pavement. The factors include type of asphalt mixture, pavement thickness, paving temperature and influence of wheel loading. TAS test of different asphalt pavement types showed that TAS of WPS under SMA (Stone Mastic Asphalt) pavement was greater than that under dense asphalt pavement. TAS of sheet membranes was improved as the compaction temperature of asphalt concrete increase, but TAS of liquid membranes were not. The influence of thickness of pavement val minimal with given laboratory test condition. TAS of sheet membranes after wheel tracking test were in the order of the sites under wheel path (UWP), before wheel tracking (BWT) and nearby wheel path (NWP). Since TAS of the same WPS of UWP was higher than TAS of BWT, wheel loading had function of pressing WPS resulting in higher adhesive strength. But liquid membranes were variable on types. The feature of detached interface after TAS test showed that sheet types were all detached in between deck concrete and WPS, and liquid types were detached in between asphalt pavement and WPS.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.6
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• pp.689-695
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• 2015

The offshore plant crews that were commissioned in the commercial startup phase boarded the offshore plant in two shifts until the end of the project. The crews who were hired by the owner side stayed in the original offshore plant during the project. However, most of the offshore plant commissioned members who were dispatched from the shipyard were accommodated in the offshore accommodation barge. For this reason, they were exposed to many accidents since there are a lot of people staying in a small space. This study suggested a method for improving survival rate at offshore accommodation barge in terms of life safety. It is assumed that the fire accident among unfortunate events which take place in the offshore accommodation barge mainly occurred. So, this study analyzed the safety evacuation for offshore plant employees using fire simulation model based on both domestic and international law criteria. In particular, When fire occurs in the offshore accommodation barge, the periodically well trained crews are followed safety evacuation procedure. whereas many employees who have different background such as various occupations, cultural differences, races and nationality can be commissioned with improper evacuation behaviors. As a result, the risk will be greater than normal situation due to these inappropriate behaviors. Therefore, This study analyzed the Required Safe Escape Time (RSET) and Available Safe Escape Time (ASET). Also it was suggested the improvement of structure design and additional arrangement of safety equipment to improve the survival rate of the residents in offshore accommodation barge.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1987.05a
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• pp.6-6
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• 1987

만성중이염은 현재 그 빈도가 줄어드는 추세에 있으나 아직도 이과 영역에서 큰 비중을 차지하는 질환이다. 또한 청력개선, 정상구조의 보존, 병변 제거의 목적을 위하여 대부분 수술적 요법이 필요하게 된다. 이에 저자들은 본 병원에서 시행한 만성 중이염 451예, 남자 238예, 여자 213예. 진주종성 중이염 170예, 비진주종성 중이염 273예에 대한 수술시 소견에 대한 임상 통계적 관찰을 한 바, 다음과 같은 결과를 얻었다. 1) 관찰대상을 술식별로 분류하면 진주종성 중이염과 비진주종성 중이염의 비가 $\circled1$ Myningoplasty ; 19.1% : 0%, $\circled2$ Tympanoplasty without mastoidectomy ; 34.5% : 14.4%, $\circled3$ Tympanoplasty with mastoidectomy ; 3.0% :12.1% 이었다. 2) 고막천공부위는, 진주종성 중이염과 비진주종성 중이염의 비가 변연부천공이 10.1% : 5.5%, 상고실천공이 38.8% : 1.4%, 중심부천증이 12.9% : 47.3%, 전천공이 32.5% : 39.6%, 고막유착이 5.6% : 6.2% 을 보였다. 3) 이소골의 상태는 진주종성중이염과 비진주종성 중이염의 비가, 모든 이소골의 손실은 26.6% : 4.3%, 모든 이소골이 정상에 가까운 예는 16.6% : 69.3%, 가장 병변이 심했던 침골 이상은 76.9% : 24.8% 를 보였다. 4) 중이강 점막소견은 진주종성 중이염과 비진주종성 중이염의 비가, 정상에 가까운 예가 16.7% : 47.0%, 병적 소견을 보인 예가 83.3% : 53.0% 이었다. 5) 진주종성 중이염과, 비진주종성 중이염에서의 안면신경관노출은 2.2% : 0.3%, 뇌막노출은 9.5% : 2.9%, 횡정맥동노출은 5.0% : 1.1%, 미로누공은 1.7% : 0% 이었다.lant, engineering service business can be said "The Software of Total Industry." Engineering service is what is called a higher business which offers specialized engineering know-how and experience. Engineering service compaines offer Its specialized knowledge and experience to government, industry and commerce. Whether the task is to modernize plant equipment, to design a building or to manage construction, an engineering company will develop and implement the most appropriate and cost effective solution. Clients use the engineering service of firm knowing that the engineer′s professional judgement is not influenced or biased by other commercial affiliations. While benefiting from the diverse experience that professional engineers can apply to a specific problem, government and industry also reduce the need for permanent in-house engineering staff. Engineering firms may be specialized or multi-disciplinary.도말표본에서와 같이 제 14 일 이전에는 호중구가, 그 이후에는 단핵구가 주종을 이루었다.>18.9dB

• Journal of Life Science
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• v.27 no.4
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• pp.464-470
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• 2017

Three Korean native cattle (KNC) and seven exotic breeds (Chikso, Hanwoo, Jeju black, Holstein, Japanese black, Charolais, Angus, Hereford, Simmental, and Cross breed) were characterized by using five microsatellite (MS) markers (INRA30, TGLA325, UMN0803, UMN0905, and UMN0929) from the sex chromosome. Genetic diversity was evaluated across the 10 breeds by using the number of alleles per locus, allele frequency, heterozygosity, and polymorphism information content (PIC) to search for locus and/or breed specific alleles, allowing a rapid and cost-effective identification of cattle samples, avoiding mislabeling of commercial beef. It was divided into two main groups from STRUCTURE analysis, one corresponding to KNC and the other to exotic cattle breeds. These results also showed specific genetic differences between KNC and exotic breeds. Nei's standard genetic distance was calculated and used in the construction of a neighbor-joining tree. Results evidenced a correspondence between genetic distance, breeds' history, and their geographic origin, and a clear separation between KNC and exotic breeds. Overall, this study evidenced that DNA markers can discriminate between domestic and imported beef, contributing to the knowledge on cattle breeds' genetic diversity and relationships by using MS markers of the sex chromosome. These markers would be useful for inhibitory effect about false sales and for building an effective tracking system.

• Elastomers and Composites
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• v.46 no.3
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• pp.211-217
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• 2011

Wood Polymer Composite (WPC) has attracted a great deal of attention in environmental industries due to renewable resources, processability, excellent physical properties and logging regulations for application to housing units and engineering construction materials. In this study, commercial WPCs were prepared by using a modular intermeshing co-rotating twin screw extruder. The effect of three main factors such as wood flour contents, coupling agent concentrations and pre-treatment of wood flour on the properties of WPCs was extensively investigated. It was found that tensile strength and thermal stability were decreased with increasing wood flour contents whereas the water absorption was increased. Addition of maleic anhydride grafted polypropylene (PP-g-MA) into WPC exhibited better physical properties. On the contrary, the water absorption was slightly decreased with PP-g-MA. Finally the sample, which was prepared with pre-treated wood flour, represented the highest tensile strength. However, the water absorption of the sample was increased due to the transition of crystalline structure of cellulose.

• Korean journal of communication and information
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• v.18
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• pp.269-303
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• 2002

This article presents a historical account of media role in the transition and consolidation period of democracy. Despite the assumption that media plays a important role in the construction of democracy, it is less clear how the media can affect the process of political change itself. This article seeks to answer some of these question, based on the Mill's macro-social comparative 'method of difference' of Korea and Spain. It is widely agreed that both states achieve democracy through transaction from above(pacts). Media role, however, differs significantly in accordance with authoritarian legacies and civic representativeness of the pacts. Whereas Korean dailies is deepening given market oligopoly and prior practices after democratization, Spain dailies market entirely changed in both structural and spiritual respects. As a result, Korean dailies substantially lacks in civic representativeness as before, contrary to Spain. Spain television settled a sort of the external pluralism. Korean television is pursuing the BBC type of internal pluralism. In Korea, television is more commercial than Spain. Consequently, Spain media serve the consolidation of democracy more than Korea on the whole.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.1
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• pp.50-55
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• 2008

In this paper, New LC VCO with $8{\sim}10.9$ GHz Band has been designed using commercial $0.35-{\mu}m$ CMOS technology. This proposed circuit is consisted of the parallel construction of the typical NMOS and PMOS cross-coupled pair which is based on the LC tank, MOS cross-coupled pair which has same tail current of complementary NMOS and PMOS, and output buffer. The designed LC VCO, which is according to proposed structure in this paper, takes a 29% improvement of the wide tuning range as 8 GHz to 10.9 GHz, and a 6.48mW of low power dissipation. Its core size is $270{\mu}m{\times}340{\mu}m$ and its phase noise is as -117dBc Hz and -137dBc Hz at 1-MHz and 10-MHz offset, respectively. FOM of the new proposed LC VCO gets -189dBc/Hz at a 1-MHz offset from a 10GHz center frequency. This design is very useful for the 10Gb/s clock generator and data recovery integrated circuit(IC) and SONET communication applications.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.6
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• pp.1029-1044
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• 2017

The Discrete Element Method (DEM) is one of the useful numerical methods to analyze the behavior of the ground formation by computing the motion and interaction using particles. The DEM has not been applied in civil engineering but also a wide range of industrial fields, such as chemical engineering, pharmacy, material science, food engineering, etc. In this study, to review a performance of the spoke-type earth pressure balance (EPB) shield TBM (Tunnel Boring Machine), the commercial software based on the DEM technology was used. An analysis of the TBM during excavation was conducted according to two pre-defined excavation conditions with the different rotation speed of a cutterhead. During the analysis, the resistant torque at the face of the cutterhead, the compressive force at the cutterhead and shield surface, the muck discharge at the screw auger were measured and compared. Upon the two kinds of excavation conditions, the applicability of the DEM analysis was reviewed as a modelling method for the TBM.

• Plant Journal
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• v.10 no.2
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• pp.38-47
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• 2014

Renewable Portfolio Standards was introduced into the system in Korea in 2012. Interest in the unutilized and renewable energy sources is increasing. and these being actively investigated. An organic rankine cycle has emerged as an alternative in order to take advantage of bio-gas engine heat of sewage treatment plants whose capacity is 1500 kW. The organic rankine cycle power system was simulated by a simulator which is a commercial program of power plant design and performance analysis. The biogas engine is operated by $460^{\circ}C$ and 2.7 kg/s flow rate in the sewage treatment plant. Working fluids(R-601a, R-123, R-245fa) are selected to use in ORC power system in this temperature range. It was the isopentane that is the best performance among three working fluids. It could be obtained net power of 163.1 kW and efficiency of 13.66% from isopentane in the simulation.

• Plant Journal
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• v.10 no.2
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• pp.28-37
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• 2014

Recently, it is considered that environment and energy are critical issues all over the world. In power generation sector in Korea, almost power stations are constructed and operated as cogeneration plants in conformity with this trend. KDHC(Korea District Heating Corporation) goes one step further adopting renewable energy technology like heat pump using wasted heat for energy-saving and environment improvement. This study investigates the performance characteristics by the location of waste heat recovery heat pumps of 5 Gcal/h capacity in 150 MW-class Gwang-gyo cogeneration plant using commercial software 'THERMOFLEX'. Prior to analysis, the simulations are performed with actual operation data, and then the validation of simulations is verified by checking the error within 2%. After verification, the simulations are carried out with 3 locations and the effect on electrical power output and heat output is analyzed. As a result, overall efficiency of cogeneration plant is the highest in the case of heat pump located before DH(District Heating) Heater because of the largest increase of heat output despite of decrease of electrical power output.