• 정보통신설비학회논문지
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• 제10권2호
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• pp.46-52
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• 2011

This paper presents adaptive spread-spectrum watermarking scheme on the H.264/AVC video. The H.264/AVC has become popular video coding since it's compression performance has been improved greatly. That is why there is not enough space for embedding watermark using the spread-spectrum method. To overcome this problem, we propose selective block embedding scheme. The blocks which don't contain non-zero DCT (Discrete Cosine Transform) coefficients are selected by value. So we have enough space to embed watermarks. Experimental result shows that proposed scheme improves recovery rates of watermark about 12% and reduces distortion of watermarked video.

• 한국수소및신에너지학회논문집
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• 제30권3호
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• pp.289-295
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• 2019

Effects of various reaction factors such as pressure, time, and temperature on clathrate formation were investigated for hydroquinone with $CO_2$ and $N_2$. Experimental and spectroscopic results indicate that $CO_2$ plays more preferential role in forming hydroquinone clathrates than $N_2$. These results can be used in application of selective $CO_2$ separation from flue gases with the formation of clathrate compounds.

• Journal of Magnetics
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• 제15권2호
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• pp.91-98
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• 2010

The paper presents results of a study on the selective separation technology of ferrous and non-ferrous metals from broken light bulbs. The proposed method is to use magnetic fluids to obtain a magnetic fluid based- separation. [1] The study was conducted using three types of waste materials: regular light bulbs, auto light bulbs and neon tubes. In order to process the waste materials, a six stages technologic flow was developed: a) separation of light bulbs components; b) Physical and chemical analysis of raw materials; c) grain conditioning of the raw material; d) dry magnetic separation of ferrous components; e) magnetic fluid separation of non-magnetic material; f) recovery of the magnetic fluid adhered to the surface of the separated material grains. [2] This study shows that magnetic fluid separation is only profitable for regular and auto light bulbs and is not profitable in the case of neon tubes.

• 한국수소및신에너지학회논문집
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• 제24권5호
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• pp.437-443
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• 2013

Clathrate samples, using hydroquinone as a host and ethylene or propylene as a possible guest, were prepared and analyzed by means of spectroscopic measurements. Obtained results showed that ethylene can form clathrate compounds with hydroquinone at 4.0MPa and room temperature, while propylene cannot form clathrate compounds. Different formation behaviors of these two olefin compounds can be applied to a clathrate-based storage/recovery of ethylene in a selective way, and can provide useful information on the cavity size of the formed clathrate compounds.

• 한국표면공학회지
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• 제36권2호
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• pp.184-193
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• 2003

Cyclic sweep voltametry was performed to investigate the electrochemical behavior of heavy metal ions and the organic additives in surface finishing process. And electrolysis using parallel plate electrode electrolyzer was carried out to simulate the treatment of real waste water. Results showed that more than 99 percent of Cu was recovered and selective recovery of Cu in mixed waste water was possible, but the possibility of economical recovery of Ni and Cr were very low due to the evolution of hydrogen gas. Electrochemical oxidation of cyanide and organic additives on anode showed very excellent removal rate. The complete removal of several hundred ppm of cynide was possible within several tens minutes and organics within 2 or 3 hours. Even in case of concentrate waste water, the complete removal of COD by using NaCl and air stirring seemed to be possible.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권6호
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• pp.386-394
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• 2001

Carboxylic acids are examples of compounds with wide industrial applications and high potential, This article presents the principles of reactive extraction along with the character-istics of tertiary amine extractants, while is given on considering the effect of the amine class and chain length, As such a brief overview the current research on reactive extraction, including the recovery of citric acid, selective amine-based extraction , and extractive fermentation is given. When discussing extractive fermentation strategies for reducing solvent toxicity are also suggested based on specific examples. Finally, solvent regeneration and stripping of extracted acid explained.

• 한국응용과학기술학회지
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• 제27권3호
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• pp.273-281
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• 2010

Nickel recovery method was studied by the wet process from the catalyst used in hydrogenation process. Nickel content in waste catalyst was about 16%. At the waste catalyst leaching system by the alkaline solution, selective leaching of nickel was possible by amine complex formation reaction from ammonia water and ammonium chloride mixed leachate. The best leaching condition of nickel from mixed leachate was acquired at the condition of pH 8. LIX65N as chelating solvent extractant was used to recover nickel from alkaline leachate. The purity of recovered nickel was higher than 99.5%, and the whole quantity of nickel was recovered from amine complex.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1464-1478
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• 2021

Selective Production of Exotic Species is an innovative plant for advanced nuclear physic studies. A radioactive beam, generated by using an UCx target-ion source system, is ionized, selected and accelerated for experimental objects. Very high vacuum conditions and appropriate safety systems to storage exhaust gases are required to avoid radiological risk for operators and people. In this paper, Failure Mode, Effects, and Criticality Analysis of a preliminary design of high activity gas recovery system is performed by using a modified Fuzzy Risk Priority Number to rank the most critical components in terms of failures and human errors. Comparisons between fuzzy approach and classic application allow to show that Fuzzy Risk Priority Number is able to enhance the focus of risk assessments and to improve the safety of complex and innovative systems such as those under consideration.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
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• pp.206-209
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• 2003

본 논문에서 제안하는 알고리즘은 심벌 타이밍 jitter 를 최소화하기 위해 가장 강한 신호를 주기적으로 감시하고, 그 신호를 적응적으로 DLL(Delayed Locked Loop)의 기준 신호로 정한다. 결과적으로 제안된 알고리즘은 DLL 추적 실패를 피할 수 있고, 기존의 알고리즘에 비하여 DLL의 정상 상태 추적 오류가 작다. 모의실험을 통하여 제안된 알고리즘의 정상상태 DLL 추적오류가 작고 다중 경로 상황에서 DLL 추적 실패를 피할 수 있음을 확인 하였다. 따라서 본 논문에서 제안하는 알고리즘은 OFDM 의 시간동기 복원 알고리즘에 적합하다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2004년도 춘계학술발표대회
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• pp.1355-1358
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• 2004

This paper describes a modification to the SACK (Selective Acknowledgement) Transmission Control Protocol's (TCP), called SACK TCP with Probing Device, SACK works in conjunction with Probing Device, for improving SACK TCP performance when more than half a window of data lost that is typical in handoff as well as unreliable media. It shows that by slightly modifying the congestion control mechanism of the SACK TCP, it can be made to better performance to multiple packets lost from one window of data.