• 한국막학회:학술대회논문집
• /
• 한국막학회 1996년도 심포지움시리즈 Jan-96 투과증발막과 응용
• /
• pp.69-90
• /
• 1996

In the chemical industry, in the pharmaceutical industry, and in a number of other industries separation processes are necessary to separate and purify products and raw materials [1,2]. Separation processes are also widely used in other applications such as in recycling valuable materials from waste streams. Unit operations for separation processes can be classified in phase separation techniques and component separation techniques based on the nature of the feed mixtures to be separated. The former techniques are used for the separation of heterogeneous mixtures, in which the feed is already present in two or more separated phases on a micro-scale. The latter are suitable for the separation of homogeneous mixtures such as gaseous mixtures and mixtures of completely miscible liquids. tn these cases the separation into individual components is generally achieved by utilizing the differences in physico-chemical properties of components, and is much more difficult compared to phase separation techniques. Separation processes such as distillation, evaporation, liquid-liquid extraction, and crystallization belong to this class.

• 대한음성학회지:말소리
• /
• 제65호
• /
• pp.153-168
• /
• 2008

We propose a new method to apply shape analysis techniques to a computational auditory scene analysis (CASA)-based speech separation system. The conventional CASA-based speech separation system extracts speech signals from a mixture of speech and noise signals. In the proposed method, we complement the missing speech signals by applying the shape analysis techniques such as labelling and distance function. In the speech separation experiment, the proposed method improves signal-to-noise ratio by 6.6 dB. When the proposed method is used as a front-end of speech recognizers, it improves recognition accuracy by 22% for the speech-shaped stationary noise condition and 7.2% for the two-talker noise condition at the target-to-masker ratio than or equal to -3 dB.

• 한국산학기술학회논문지
• /
• 제15권1호
• /
• pp.243-248
• /
• 2014

본 연구의 목적은 농촌진흥청 국립원예특작과학원 감귤시험장에서 개발된 감귤의 플라보노이드 성분의 추출 및 정제방법 개발의 기술가치를 IRR, NPV를 통해 평가하는 것이다. 이는 농업 R&D사업의 효율성과 실용성 제고를 위하여 이용될 수 있을 것이다. 분석결과에 따르면, 감귤의 플라보노이드 성분의 추출 및 정제방법 개발에 따른 기술 가치평가액은 3,155 백만원 ~ 6,518 백만원으로 추정되고, 추출물 적용단가에 따라 순현재가치는 5,541~18,773백만원, 내부수익율 IRR은 할인율(11.9%)보다 큰 28.3%~61.2%로 높게 나타나 경제적 타당성이 높은 것으로 평가된다.

• 약학회지
• /
• 제53권2호
• /
• pp.60-68
• /
• 2009

In terms of chiral issue, two enantiomers of chiral drugs often differ significantly in their pharmacological, toxicological and pharmacokinetic profile. Chiral switches of racemic drugs have been redeveloped as single enantiomers. Several chiral resolution techniques in chirotechnology are introduced and the most used chiral HPLC chromatographic method among several chiral analysis techniques is described with its several advantages. Several types of chiral HPLC columns derived from their chiral selectors are discussed with their property and applications for enantiomer separation.

• 대한방사성의약품학회지
• /
• 제2권2호
• /
• pp.84-95
• /
• 2016

Considerably increasing interest in using the theranostic isotopes/ isotope pairs of radiometals like $^{44/47}Sc$ and $^{64/67}Cu$ for diagnosis and/or therapeutic applications in the nuclear medicine procedures necessitates its reliable production and supply. Separation and purification of no-carrier-added (NCA) isotopes from macro quantitates of the irradiated target matrix along with other impurities is a cardinal procedure amongst several other steps involved in its production. Multitudinous methods including but not limited to liquid-liquid (solvent) extraction, extraction chromatography (EXC), ion exchange, electrodeposition and sublimation are routinely applied either solitarily or in combination for the separation and purification of radioisotopes depending on their production routes, radioisotope of interest and impurities involved. However, application of EXC though has shown promises towards the numerous separation techniques have not received much attention as far as its application prospects in the field of nuclear medicine are concerned. Advances in the recent past for application of the EXC resins in separation and purification of the several medically important radioisotopes at ultra-high purity have shown promising behavior with respect to their operation simplicity, acidic and radiolytic stability, separation efficiencies and speedy procedures with the enhanced and excellent extraction abilities. In this mini review we will be talking about the recent developments in the application and the use of EXC techniques for the separation and purification of $^{44/47}Sc$ and $^{64/67}Cu$ for medical applications. Furthermore, we will also discuss the scientific and practical aspects of EXC in the view of separation of the NCA trace amount of radionuclides.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2022년도 학술발표회
• /
• pp.149-149
• /
• 2022

Accurate quantitative evaluation of baseflow contribution to streamflow is imperative to address seasonal drought vulnerability, flood occurrence and groundwater management concerns for efficient and sustainable water resources management in watersheds. Several baseflow separation algorithms using recursive filters, graphical method and tracer or chemical balance have been developed but resulting baseflow outputs always show wide variations, thereby making it hard to determine best separation technique. Therefore, the current global shift towards implementation of artificial intelligence (AI) in water resources is employed to compare the performance of deep learning models with conventional hydrograph separation techniques to quantify baseflow contribution to streamflow of Piney River watershed, Tennessee from 2001-2021. Streamflow values are obtained from the USGS station 03602500 and modeled to generate values of Baseflow Index (BI) using Web-based Hydrograph Analysis (WHAT) model. Annual and seasonal baseflow outputs from the traditional separation techniques are compared with results of Long Short Term Memory (LSTM) and simple Gated Recurrent Unit (GRU) models. The GRU model gave optimal BFI values during the four seasons with average NSE = 0.98, KGE = 0.97, r = 0.89 and future baseflow volumes are predicted. AI offers easier and more accurate approach to groundwater management and surface runoff modeling to create effective water policy frameworks for disaster management.

• 자원리싸이클링
• /
• 제16권4호
• /
• pp.47-60
• /
• 2007

현대생활은 플라스틱 없이는 성립되지 않으며, 폐플라스틱량도 방대하다. 한편 2003년부터 EPR(확대생산자책임)제도가 도입됨에 따라 생활계 혼합 폐플라스틱 발생량이 급증하였다. 플라스틱 리싸이클링에는 플라스틱-플라스틱 간의 선별이 기본으로 되어 있다. 플라스틱간의 선별기술 고도화가 폐플라스틱 재활용의 관건이라 하여도 과언이 아니다. 본고에서는 이와 같은 관점에서 플라스틱 상호선별에 초점을 맞추어, 연구동향과 실용화되어 있는 기술을 기술하고저 한다.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제18권5호
• /
• pp.46-55
• /
• 2013

The main objective was to evaluate the efficiencies of different separation techniques, such as gravity separation, magnetic separation, and aerial separation. Zinc and cadmium removal efficiencies by gravity separation and magnetic separation were 28.3~29.3% and 19.1%, respectively, and were higher than the efficiency obtained by aerial separation. Results showed that the combination of gravity separation and magnetic separation in series which was to maximize the removal efficiencies gave removal efficiency of 21.5~38.7% for zinc and 22.1~23.4% for cadmium. The mass of soil meeting the regulation standards for zinc and cadmium after retrieval from the combined separation process accounted for approximately 80% of the treated soil that would be reusable without the pre-treatment procedure as the neutralization process using in the soil washing method. Physical separation techniques utilizing heavy metal properties are the alternative method to remediate heavy-metal contaminated soils in environmental and economic aspects.

• 한국항공우주학회지
• /
• 제41권8호
• /
• pp.673-679
• /
• 2013

안전분리 비행시험에서 사진계측 기법을 이용하여 분리되는 외부장착물의 분리특성을 분석하였다. 한 대의 카메라를 사용하여 6자유도를 해석할 수 있는 기법을 적용하였으며, 사진계측의 이론적인 배경과 MIL-HDBK-1763에서 제시하는 내용을 토대로 계측 요구조건을 정립하고 비행시험에 적용하여 분리궤적을 추출하였다. 사진계측의 오차에 영향을 주는 입력변수들의 불확실성을 경험에 의해 추정하였으며, 각각의 입력변수들에 의한 궤적오차를 고려하여 분리안전성을 분석하였다.

• 대한방사성의약품학회지
• /
• 제2권1호
• /
• pp.43-50
• /
• 2016

$^{89}Zr$ with the favorable nuclear decay kinetics and chemical properties is an appealing radiometal for its application in immuno-PET using radiolabeled monoclonal antibodies. Rising demand of ultrahigh purity and high-specific activity $^{89}Zr$ has propelled the radiochemist worldwide to develop an overall efficacious method for its promising separation from the target matrix $^{89}Y$. The requirement of elevated radiochemical purity (${\geq}$ 99.99%) has accelerated the efforts since last two decades to achieve higher decontamination and separation factors of carrier free $^{89}Zr$ over $^{89}Y$ using several suitable separation techniques. However, each of the technique has its own pros and cons which prior to its actual medical application needs to be optimized and thoroughly scrutinized to avoid further complications during radiolabelling of the pharmaceuticals. In this short review article we will specifically consider as well focus on the historical development and the recent advances on the radiochemical separation of $^{89}Zr$ from $^{89}Y$ which will be helpful for the separation scientist involved in this area to understand the existing available means and plan the strategy to investigate and develop the novel techniques to overcome the problems involved in the present methods.