• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.7
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• pp.664-672
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• 2009

In this paper we propose an on-glass antenna which consists of conducting dual center striplines and multi-loaded striplines. Multi-loaded striplines and dual center lines were employed for achieving a broad matching bandwidth and improving a vertical radiation gain, respectively. The detail design parameters were determined using the Pareto genetic algorithm with an full wave EM simulator. The optimized design was built and installed on a commercial vehicle, and the antenna performances such as the return loss and the radiation gain were measured in a semi-anechoic chamber. The measurement results showed the matching bandwidth($S_{11}$<-3 dB) of about 49 % in the T-DMB frequency band, the vertical gain of about -3 dBi along the bore-sight direction, and the average gain of about -10 dBi along the azimuth direction.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.2
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• pp.183-192
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• 2009

SAR(Synthetic Aperture Radar) is an all-weather imaging radar and is widely used in military and civil application. Especially high-resolution SAR images are very important in military purpose because it can be used at target recognition application. LIG Nex1 developed a SAR system called NexSAR with bandwidth of 600 MHz and resolution of 30 cm to obtain technologies required for high-resolution SAR. To achieve 600 MHz bandwidth of waveform generator, two DDSs are used and its output signals are SSB modulated. And deramp technique is used to reduce the sampling rate of ADC at high resolution mode. NexSAR has stripmap and spotlight modes and its functionality and performances are evaluated through ground and flight tests.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.10
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• pp.1161-1168
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• 2014

As rapidly growing industry, ICT industry is emphasized for its importance and the demand to figure out for the performances of investment of R&D for ICT have been increasing. The performance for investment of R&D analyze mainly as commercialization, sales, hiring employee and intellectual property and so on. In this paper, we propose an analytical method for performance as focusing an application time of patent that are acquired as a result after perform the national project of ICT. We classify 4 subdivision technologies and 17 detailed classification of Korean industrial standard for 35,551 item of ICT area among national R&D project. This paper proposes computational method for required time about patent's performance. As a analyzed result we verify that the activity of technology's commercialization is most active in communication as 1.2 year of ICT among national project.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.2
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• pp.97-113
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• 2011

While the role of universities in the modern society has long been a key agenda of discussion, Korean universities have recently tried to get good results in league tables, mostly published by major media. Although the criteria of evaluation are developed through benchmarking and thoughtful discussion, they are still in the process of development and fragile to the question whether they really suggest the future direction of universities. The study seeks to find whether the number of UIC(university industry co-authored articles), as suggested by a few scholars, is meaningful and feasible as an alternative or complement to current performance indices of universities. The adoption of UIC implicitly means that a key role of university should be developing and diffusing knowledge to the society by working with industry participants. We found limited evidence that the index of UIC has meaningful discrepancy with current indices for research, which opens up a new discussion.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.6
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• pp.644-652
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• 2013

This paper describes the development and field experiments of Manta-type Unmanned Underwater Vehicle (UUV). Various simulations for Manta UUV are performed by using the nonlinear 6-DOF motion of equations. Through this simulation we verified the motion performances of Manta UUV. To acquire the blueprint of Manta UUV, it was designed with the simulation results. The Manta UUV uses a Doppler Velocity Log (DVL), gyrocompass, GPS, pressure sensor and other minor sensors, applied to measure the motion, position and path of Manta UUV. For its propulsion and changing a direction in the underwater, one vertical fin and four horizontal fins are installed at the hull of UUV. The Manta UUV system was verified with motion and autonomous navigation test at field.

• Applied Chemistry for Engineering
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• v.24 no.2
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• pp.171-176
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• 2013

The need of volatile organic compound (VOC) free coating material has been increased to solve environmental problems such as the global warming. Nowadays, about 70~80% of coating materials used in the worldwide are a liquid type. Therefore, the development of non-solvent coating material that can minimize VOCs emissions is necessary to solve the global warming problem. In this study, acrylic monomers were added to develop non-solvent paints in order to improve disadvantages of the poor adhesion of a conventional phenolic resin caused by acidification. As a result, the blend resins of 2.818 Mpa phenol- formaldehyde resin/poly methyl methacrylate (PE/PMMA) has the best properties and performances for the adhesives.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.7
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• pp.552-560
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• 2013

Airplane Buhwal is the first light airplane which is designed and made in South Korea. Restoration of airplane Buhwal is designed based on the one made by Korean Airforce in 2004 but there are some changes also. It uses aluminum main wing, electronic indicator, BRS(Ballistic recovery parachute) and black box for improved performance. In this paper, for the restorated Buhwal, major design changes are introduced, structure, aerodynamic and stability analysis are reviewed and improved performances which is proven through flight test are shown. This study will be a big help for domestic light airplane development.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.113-116
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• 2005

In this paper, silicon thin-film solar cells(Si- TFSC) and a-Si/c-Si heterojunction solar cells(HJ-cell) are investigated. The Si-TFSC was prepared on glass substrate by depositing $1-3{\mu}m$ thin-film silicons by glow discharge method. The $a-Si:H/{\mu}c-Si:H$ tandem solar cells on textured ZnO:A1 TCO (transparent conducting oxide) showed improved Jsc in top and bottom cells than that on $SnO_2:F$ TCO. This enhancement of jsc resulted from improved light trapping effect by front textured ZnO:A1. The a-Si/c-Si HJ-cells with simple structure without high efficiency features are suffering from low Voc and Jsc. The improvement of front nip and back interface properties by adopting high quality silicon-films at low temperature should be done both for increasing device performances and production cost.

• Journal of Society of Preventive Korean Medicine
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• v.11 no.2
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• pp.101-112
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• 2007

Oriental public health programs have been introduced for the purpose of providing comprehensive oriental health care services to community people including vulnerable classes, increasing the accessibility of oriental medicine and the public benefit, and further more elevating the health promotion and the quality of life of community people. Promoting these programs since 2002 in earnest, it is evaluated that it has made a lot of performances. In the other side, it showed many problems and policy issues also. This study is accomplished to analyze the problems made since the system was introduced and until now, 2007, and with this analysis, to examine policy issues and the reasonable recommendations for its development Major problems are as follows. First, fundamental notions and identity of oriental public health programs are not positioned accurately. Second, the infra-structure construction for effective propulsion of business is insufficient. Third, it is short of the capacity for program implementation of oriental public health doctors, related manpower, and health centers. Fourth, oriental health promotion programs that can fulfill the various health needs of community people are deficient. Fifth, active aid of the government and the oriental medical world as well as legal and systematical support for oriental public health programs is insufficient. As a result, to solve the problems and induce the successful settlement of the program, the policy recommendations such as (i) the fundamental notions of the program and establishment of approach strategies, (ii) reinforcement of the foundation of the program implementation, (iii) capacity enhancement of the manpower of the program implementation, and (iv) effective building of supportive system of the program are presented.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.91-102
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• 2009

A traffic accident prediction model developed using various design variables(road design variables, geometric variables, and traffic environmental variables) is one of the most important factors to safety design evaluation system for roads. However, statistical accident models have a crucial problem not applicable for all intersections. To make up this problem, this study developed AMFs(Accident Modification Factors) through statistical modeling methods, historical accident databases, judgment from traffic experts, and literature review by considering design variable's characteristics, traffic accident rates, and traffic accident frequency. AMFs developed in this study include exclusive left-turn lane, exclusive right-turn lane, sight distance, and intersection angle. Predictabilities of the developed AMFs and the existing accident prediction models are compared with real accident historical data. The results showed that performances of the developed AMFs are superior to the existing statistical accident prediction models. These findings show that AMFs should be considered as a important process to develop safety design evaluation algorithms. Additionally, AMFs could be used as an index that can judge the impact of corresponding design variables on accidents in rural intersections.