• Nuclear Engineering and Technology
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• 제51권7호
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• pp.1866-1870
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• 2019

Residual salt separation is an essential step in pyroprocessing because its reaction products, as prepared by electrochemical unit processes, contain frozen residual electrolyte species, which are generally composed of alkali-metal chloride salts (e.g., LiCl, KCl). In this study, a simple technique that utilizes high-temperature gas flux as a driving force to melt and push out the residual salt in the reaction products was developed. This technique is simple as it only requires the use of a heating gun in combination with a gas injection system. Consequently, $LiNO_3-ZrO_2$ and $LiCl-ZrO_2$ mixtures were successfully separated by the high-temperature gas injection (separation efficiency > 93%), thereby demonstrating the viability of this simple technique for residual salt separation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.31-34
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• 2003

In this paper, we describe a method for separating text lines in handwritten Korean address images. The most remarkable feature of the proposed method is to use a modified projection technique. named a partial projection technique. A projection based text line separation method which projects the whole address image in horizontal direction to find split points for text line separation cannot avoid failing separation in case of images with a little skew or overlap between vertically neighboring text lines. To overcome this problem, we have introduced a partial projection technique which splits an address image into a few partial address images to be equal width and then project them each horizontally. The experiment done with 989 handwritten Korean address images extracted from live mails shows the superiority of the proposed method. The correct text-line separation rate fir the testing images was about 91.5％.

• 센서학회지
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• 제30권2호
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• pp.119-124
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• 2021

Isolation and separation of biological nanoparticles, such as cells and extracellular vesicles, are important techniques for their characterization. Dielectrophoresis (DEP) based on microfluidic chips is an effective method to isolate and separate the nanoparticles. However, the electrodes of the DEP chips are electrolyzed by the electrical signals applied to the nanoparticles. Thus, the isolation/separation efficiency of the nanoparticles is reduced considerably. Through this study, we developed a microfluidic DEP chip for reliable isolation/ separation of nanoparticles and developed a passivation technique for the protection of the DEP chip electrodes. The electrode passivation process was designed using a hydrogel and the stability of the hydrogel passivation layer was verified. The fabricated DEP chip and the proposed passivation technique were used for the collection and dispersion of the fluorescent polystyrene nanoparticles. The proposed chip and the technique for isolation and separation of nanoparticles can be leveraged in various bioelectronic applications.

• Nuclear Engineering and Technology
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• 제50권7호
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• pp.1184-1189
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• 2018

Pyroprocessing uses various molten salts during electrochemical unit processes. Reaction products after the electrochemical processes must contain a significant amount of residual salts to be separated. Vacuum distillation is a common method to separate the residual salts; however, its high operation temperature may cause side reactions. In this study, a simple rotation technique using centrifugal force was suggested to separate the residual salts from the reaction products at relatively low temperature compared to the distillation technique. When a reaction product container with porous wall rotates inside a vessel heated above the melting point of the residual salt, the residual salt in the liquid phase is separated through centrifugal force. It was shown that the $LiNO_3-Al_2O_3$ mixture can be separated by this technique to leave solid $Al_2O_3$ inside the container, with a separation efficiency of 99.4%.

• 자원리싸이클링
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• 제15권1호
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• pp.28-36
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• 2006

2004년 이후 EPR 제도의 시행과 더불어 폐플라스틱을 함유한 물질의 소각과 매립을 법으로 규제함에 따라 폐플라스틱 재활용의 필요성이 가중되고 있다. 본 연구는 생활계 폐플라스틱 재활용을 위한 정전선별 기술의 개발을 목적으로, 하전물질과 하전장치를 개발하여 선별효율을 높이고자 하였다. 따라서 우리는 대상 플라스틱의 하전효율과 재질분리에 적합한 하전장치 및 마찰하전형정전선별기를 개발하여 2종 혼합 플라스틱으로부터 PVC를 $99\%$ 이상 제거하였으며, PET와 같이 PVC 함량을 규제하는 경우 최적 실험조건에서 PET 회수율 $80\%$로 PVC를 $99.99\%$ 까지 제거할 수 있는 기술도 개발하였다. 또한 3종 혼합 플라스틱은 $98\%$이상으로 분리하여 플라스틱의 재활용을 높일 수 있는 재질분리 기술을 확립하였다.

• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2005년도 추계정기총회 및 제26회 학술발표대회 고분자리싸이클링기술 특별심포지엄
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• pp.23-33
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• 2005

2004년 이후 EPR 제도의 시행과 더불어 폐플라스틱을 함유한 물질의 소각과 매립을 법으로 규제함에 함에 따라 폐플라스틱 재활용의 필요성이 가중되고 있다. 본 연구는 생활계 폐플라스틱 재활용을 위한 정전선별 기술개발로써, 하전물질과 하전장치 개발에 따라 선별효율을 높일 수 있다. 따라서 우리는 대상 플라스틱의 하전효율과 재질분리에 적합한 하전장치와 마찰하전형정전선별기 개발하여 2종 혼합 플라스틱으로부터 PVC를 99% 이상 제거하였으며, PET와 같이 PVC 함량을 규제하는 경우 최적 실험조건에서 PET 회수율 80%로 PVC를 99.99% 까지 제거할 수 있는 기술도 개발하였다. 또한 3종 혼합 플라스틱은 98%이상으로 분리하여 플라스틱의 재활용을 높일 수 있는 재질분리 기술을 확립하였다.

• International Journal of Aeronautical and Space Sciences
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• 제2권2호
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• pp.1-18
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• 2001

A numerical technique for simulating the separation dynamics of strap-on boosters jettisoned in the dense atmosphere is presented. Six degree of freedom rigid body equations of motion are integrated into the three-dimensional unsteady Navier-Stokes solution procedure to determine the dynamic motions of strap-ons. An automated Chimera overlaid grid technique is introduced to achieve maximum efficiency for multi-body dynamic motion and a domain division technique is implemented in order to reduce the computational cost required to find interpolation points in the Chimera grids. The flow solver is validated by comparing the computed results around the Titan IV launch vehicle with experimental data. The complete analysis process is then applied to the. H-II launch vehicle, the central rocket in japans space program, the CZ-3C launch vehicle developed in China and the KSR-III, a three-stage sounding rocket being developed in Korea. From the analyses, separation trajectories of strap-on boosters are predicted and aerodynamic characteristics around the vehicles at every time interval are examined. In addition, separation-impulse devices generally introduced for safe separation of strap-ons are properly modeled in the present paper and the jettisoning force requirements are examined quantitatively.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1991년도 추계학술대회 논문집
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• pp.105-109
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• 1991

A computer aided flatness calibration system has been developed. Rectangular grids based measurement procedure is proposed with closing error technique. giving advantages over conventional diagonal measurement procedures (‘Union Jack’). A new analysis technique has been developed for flatness evaluation called ‘ETT(Enclose Tilt technique)’, enabling minimum separation definition which is acknowledged as standard term for flatness definition. Practical assessment shows the performance of the developed system.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.41-53
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• 2013

The study is to propose the optimal separation technique of heavy metals (Pb and Zn) contaminated in soil for improving the removal efficiency by various applicable techniques. The heavy metal contaminated soil samples near abandoned mine X-1 and X-2 were used for the study. Firstly, the wet classification process was shown more than 80% of removal efficiency for lead and zinc. Meanwhile, the magnetic separation process was shown low removal efficiency for lead and zincs because those heavy metals were non-magnetic materials. For the next step, the flotation separation process was shown approximately 24.4% of removal efficiency for zinc, while the gravity concentration process was shown approximately 57% of removal efficiency for lead, and 19.9% of removal efficiency for zinc, respectively. Therefore, zinc contaminated in soil would be effectively treated by the combination technique of the wet classification and the flotation technique. Meanwhile, lead contaminated in soil would be effectively treated by the combination technique of the wet classification process and the flotation process. Furthermore, the extraction of organic matter was shown more effective with aeration, 3% of hydrogen peroxide and 3% of lime such as calcium hydroxide.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.789-792
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• 2005

The dominant noise sources of Diesel Multiple Units are powerpack, which is composed of engine, transmission and cooling system, noise and wheel-rail rolling noise. The interior noise of a running vehicle is determined by structure-borne noise and air-borne noise from these noise sources. The contributions of interior noise from each noise source are calculated by air-borne transfer functions and structure-borne transfer functions of noise sources. In this paper, source separation technique is proposed to determine these transfer functions from the results of stationary and running tests of existing vehicle. With this technique, it is possible to get hold of contributions of interior noise from .noise sources of running vehicle. This source separation technique makes it possible to take efficient measures for reduction of interior noise at the early car-development stage.