• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.155-157
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• 2006

송전전압이 점차 초고압화되면서 절연체의 유전특성을 개선하여 송전용량을 향상시키고, 절연내력을 높여 케이블 외경을 저감시키려는 시도에 따라 우수한 유전특성 및 절연내력을 갖는 폴리머 절연층과 기계적 특성, 절연유와의 적합성이 우수한 크라프트지의 장점을 혼합시킨 반합성지가 개발되어 전력케이블의 주절연재료로 사용되고 있다. 본 논문은 LS전선이 국내최초로 개발한 400 kV급 반합성지 전력케이블 및 접속함 개발과정 및 이와 관련된 요소기술에 대해 기술하였다. 송전시스템에서 요구되는 유전특성의 반합성지를 설계 제작하여, 기존 크라프트 절연지 대비 유전손실은 50% 수준, 절연내력은 125%이상의 반합성지를 개발하였고, 반합성지 고유의 특성인 팽윤율을 조절하여 케이블을 제조하였다. 반합성지 절연 케이블에 필요한 접속함에서는 보강절연재로 케이블과 동일한 반합성지를 사용하여 전체적인 3기를 감소시키고, 열저항성을 줄이고자 노력하였다. 또한, 접속함 조립공정에 필요한 저온연공법을 개발하여 반합성지에 열적 스트레스를 최소화하였다. 상기 관련기술의 개발 결과로, IEC 60141, AEIC CS2-97 및 NGTS 3.5.1에 근거하여 400 kV급 반합성지 OF 케이블 및 접속함에 대해 국제 공인기관인 KEMA의부터 Type Test을 인증받았다.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.83-90
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• 2018

We have studied the optimal conditions for design and development on the communication device for a bilateral, and it's electrodes for transmitting electric signal are constructed on the $36^{\circ}$ rotated $LiTaO_3$ substrate by evaporating Al-Cu(W 30%) alloy. At first, we manufactured three kind of samples using this method, and selected two samples as similar with frequency, ripple and passband characteristics, and then we connect two samples by series in order to make bilateral devices. As results, we obtained that the electrode structure has better characteristics then the others, when it's width of reflector and electrode are $1{\lambda}/4$, $1{\lambda}/12$ respectively, and it's frequency is approximately 190.3MHz. Near future, I hope to help the manufacture for communication devices for the multi-channel and the duplex filter.

• Journal of Convergence for Information Technology
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• v.7 no.5
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• pp.103-109
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• 2017

A pressure vessel is a cylindrical container that accommodates a pressurized fluid. In real life, there are propane canisters and butane canisters. According to data from the Korea Gas Safety Corporation, The number of domestic gas accidents is average 33 cases of domestic gas accidents occurred per year and 20.8 for mobile butane gases. The purpose of this study was to investigate a method to prevent this kind of explosion. Common studies include forced drain through safe holes, forced separation of butane canisters, and manufacturing of high-strength steel. This paper uses a concept that reduces stress inside the cylinder using prestressed method that precede compression. In other words, install a long liner in both ends of the pressure vessel. I want to develop a safety device that acts like a gas intermediate valve.

• Journal of Convergence for Information Technology
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• v.10 no.3
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• pp.217-226
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• 2020

The study was conducted to investigate the improvement nail health in middle-aged women aged 40~60 years who intake soybean koji by incubating Aspergillus oryzae(황국균), and utilized non-fermented soybeans as a control group and soybean koji as an experiment group for eight weeks. After clinical trials, the lifting and cracking conditions of the nails in the experiment group were improved, The moisture content increased 5.1 times compared to the control group, The water loss was 1.4 times less the reduction to the control group. and nail thickness increased by 1.9 times compared to controls. Wrinkles on the surface improved by about 2.4 times compared to the control group. In conclusion, consumption of this soybean koji of A. oryzae's has been shown to have an impact on improving nail is expected to be used Therefore, I propose this soybean koji of A. oryzae's as an inner beauty for improving nail is in middle-aged women aged 40~60 years.

• Journal of Electrical Engineering and Technology
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• v.9 no.2
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• pp.433-440
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• 2014

In this study, a method for the low-carbon active distribution system (ADS) planning is proposed. It takes into account the impacts of both network capacity and demand correlation to the renewable energy accommodation, and incorporates demand response (DR) as an available resource in the ADS planning. The problem is formulated as a mixed integer nonlinear programming model, whereby the optimal allocation of renewable energy sources and the design of DR contract (i.e. payment incentives and default penalties) are determined simultaneously, in order to achieve the minimization of total cost and $CO_2$ emissions subjected to the system constraints. The uncertainties that involved are also considered by using the scenario synthesis method with the improved Taguchi's orthogonal array testing for reducing information redundancy. A novel cuckoo search (CS) is applied for the planning optimization. The case study results confirm the effectiveness and superiority of the proposed method.

• Nuclear Engineering and Technology
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• v.50 no.2
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• pp.253-258
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• 2018

A microcell $UO_2$ pellet, as an accident-tolerant fuel pellet, is being developed to enhance the accident tolerance of nuclear fuels under accident conditions as well as the fuel performance under normal operation conditions. Improved capture-ability for highly radioactive and corrosive fission product (Cs and I) is the distinct feature of a ceramic microcell $UO_2$ pellet, and the enhanced pellet thermal conductivity is that of a metallic microcell $UO_2$ pellet. The fuel temperature can be effectively decreased by enhanced thermal conductivity. In this study, the material concepts of metallic and ceramic microcell $UO_2$ pellets were designed, and the fabrication process of microcell $UO_2$ pellets embodying the designed concept was developed. We successfully implemented the microcell $UO_2$ pellets and produced microcell $UO_2$ pellets. In addition, an assessment of the out-of-pile properties of a microcell $UO_2$ pellet was performed, and the in-reactor performance and behavior of the developed microcell pellets were evaluated through a Halden irradiation test. According to the expectations, the excellent performance of the microcell $UO_2$ pellets was confirmed by the online measurement data of the Halden irradiation test.

• Bulletin of the Korean Chemical Society
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• v.21 no.7
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• pp.720-726
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• 2000

The analytic gradient method for the equation-of-motion coupled-cluster singles and doubles (EOM-CCSD) energy has been extended to employ a reduced molecular orbital (MO) space. Not only the innermost core MOs but also some of the outermost virtua l MOs can be dropped in the reduced MO space, and a substantial amount of computation time can be reduced without deteriorating the results. In order to study the magnitudes and trends of the effects of the dropped MOs, the geometries and vibrational properties of the ground and excited states of BF, CO, CN, N2, AlCl, SiS, P2, BCl, AIF, CS, SiO, PN and GeSe are calculated with different sizes of molecular orbital space. The 6-31 G* and the aug-cc-pVTZ basis sets are employed for all molecules except GeSc for which the 6-311 G* and the TZV+f basis sets are used. It is shown that the magnitudes of the drop-MO effects are about $0.005\AA$ in bond lengths and about 1% on harmonic frequencies and IR intensities provided that the dropped MOs correspond to (1s), (1s,2s,2p), an (1s,2s,2p,3s,3p) atomic orbitals of the first, the second, and the third row atoms, respectively. The geometries and vibrational properties of the first and the second excited states of HCN and HNC are calculated by using a drastically reduced virtual MO space as well as with the well defined frozen core MO space. The results suggest the possibility of using a very smalI MO space for qualitative study of valence excited states.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.17-23
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• 2019

In this paper, I propose a system development methodology that accepts images taken by camera attached to drone in real time while controlling mini drone and recognize and confirm the face of certain person. For the development of this system, OpenCV, Python related libraries and the drone SDK are used. To increase face recognition ratio of certain person from real-time drone images, it uses Deep Learning-based facial recognition algorithm and uses the principle of Triples in particular. To check the performance of the system, the results of 30 experiments for face recognition based on the author's face showed a recognition rate of about 95% or higher. It is believed that research results of this paper can be used to quickly find specific person through drone at tourist sites and festival venues.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.104-114
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• 2019

This study was to find factors affecting on recognition and performance of peripheral intravenous infusion management among pediatric nurses. In analysis using SPSS/Win 24.0, the average scores of recognition and performance were 3.34±0.39, 3.42±0.37 out of 4 each. 'Maintenance and exchange' and 'education' were the lowest each among subdomains. There're significant differences in recognition and performance according to working departments et. al.(p=.039, p<.001), and there's a positive correlation between recognition and performance(r=.591, p<.001). Factors affecting on recognition were performance(β=.57) and working department(β=.22), and on performance were recognition(β=.57) and educated experience(β=.19). And explanation rate were 41.2%, 41.4% each in stepwise multiple regression. In conclusion, recognition and performance were mutually influencing factors. Therefore, it is needed to increase performance by preparing measures to improve recognition of peripheral intravenous infusion management.

• Journal of Convergence for Information Technology
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• v.8 no.6
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• pp.117-122
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• 2018

In this paper, we review the security issues reported by the organizations every year and analyze the similarities and differences with the concerns that the practitioners engaged in the IT environment are concerned about the necessary security matters. Interviews and questionnaires were collected for practitioners working in various IT work environments such as government agencies, financial companies, general companies, airlines, etc. to gather their opinions on the concerns of future information security. We analyzed the collected opinions and derived key keywords. The results should be compared with the security issue keywords or statistical data reported by the security companies or related organizations in the first half and the second half of each year to find common security trends and to analyze the differences and supplement them I checked whether there was any danger. We will comprehensively analyze key security issues reported by security companies and information security related organizations and future security concerns predicted by IT practitioners to prepare for the security threats of the current era of the fourth industrial revolution.