• 유기물자원화
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• 제29권1호
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• pp.5-17
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• 2021

본 연구는 하수슬러지 소각재에 비교적 높은 함량으로 존재하는 인을 회수하기 위한 국내외 사례를 조사한 문헌연구로서 습식방법 및 열화학적 방법에 의한 인의 회수 및 중금속 제거와 관련한 실험조건과 영향인자 등을 논의하였다. 하수슬러지 소각재의 인 회수 기술 상용화를 위해서는 인 회수과정에서 발생되는 폐수, 잔재물의 처분, 첨가 약품과 에너지 소모의 최소화 등 전체 시스템의 경제성 측면에서 소각시설과 연계한 집적처리공정이 바람직할 것으로 판단된다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.446-448
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• 2008

A new plasma display panel sustaining driver using single side sustaining technique with the dual resonant method is proposed. Since this circuit enables to reduce switches in energy recovery circuit with keeping voltage stress like that of prior circuit, it can be low cost circuit comparing with a conventional driver. To integrate sustain function into one side with single power source in the driver, a charge pump method is adopted to make negative sustaining voltage and achieve dual resonant energy recovery on sustaining modes.

• Journal of Power Electronics
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• 제9권1호
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• pp.93-99
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• 2009

A new plasma display panel sustaining driver using single side sustaining technique with a dual resonant method is proposed in this paper. Since this circuit enables to keep device voltage stress same as the prior circuit, it can be a low cost circuit compared to a conventional driver. To integrate the sustaining function into one side with a single power source in the driver, a charge pump method is adopted to make negative sustaining voltage and to achieve dual resonant energy recovery on the sustaining modes.

• 한국분말재료학회지
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• 제16권5호
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• pp.351-357
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• 2009

A two-step recovery method was developed to produce copper powders from copper chloride waste solution as byproducts of MoO$_3$ leaching process. The first step consisted of replacing noble copper ions with external Fe$^{3+}$ ions which were formed by dissolving iron scraps in the copper chloride waste solution. The replaced copper ions were subsequently precipitated as copper powders. The second step was cementation of entire solution mixture to separate (pure) copper powders from aqueous solution of iron chloride. Cementation process variables of temperature, time, and added amount of iron scraps were optimized by using design of experiment method and individual effects on yield and efficiency of copper powder recovery were investigated. Copper powders thus obtained from cementation process were further characterized using various analytical tools such as XRD, SEM-EDS and laser diffraction and scattering methods.Cementation process necessitated further purification of recovered copper powders and centrifugal separation method was employed, which successfully yielded copper powders of more than 99% purity and average 1$\sim$2$\mu$m in size.

• 정보보호학회논문지
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• 제26권1호
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• pp.125-134
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• 2016

MySQL 데이터베이스는 현재 데이터베이스 시장에서 높은 점유율을 보이며 많은 사용자들이 사용한다. MyISAM 스토리지 엔진의 경우, 이전에 디폴트 엔진으로 사용되었음에도 불구하고 실질적인 레코드 복구 방법이 존재하지 않았다. 삭제된 레코드에는 데이터베이스 수사 시 중요한 증거로 쓰일 수 있는 정보가 존재할 가능성이 높으며, 수사관이 방대한 양의 데이터베이스를 직접 조사하여 일일이 정보를 판별하는 것은 거의 불가능하다. 본 논문에서는 MySQL MyISAM 데이터베이스 구조를 분석하여 삭제된 레코드의 복구 기법을 제안하며 이를 도구로 구현하여 실험한 결과를 제시한다.

• 대한임상검사과학회지
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• 제36권2호
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• pp.98-109
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• 2004

The lower limit of detection, precision, setting method of target value, reportable range determination, recovery, linearity, and comparison study with another equipment was evaluated for the Toshiba-120FR chemistry autoanalyzer which was newly introduced at the Daejeon Veteran Hospital in Dec. 2003. Nineteen kinds of test for AST, ALT, ALP, LDH, GGT, TP, ALB, GLU, T-cho, T-bil, TG, UA, CAL, IP, AMY, HDL-C, LDL-C, Cre and BUN were performed to evaluate the lower limit of detection, precision, setting method of target value, reportable range determination, recovery, linearity, and comparison study with other equipment according to the NCCLS guidelines(EP5-A, EP6-P, EP9-A). The Toshiba-120FR autochemical analyzer showed good precision for all tested items. The data concerning the lower limit of detection, precision(total CV 0.47%~3.65%), setting method of target value, reportable range determination, recovery(93%~111%), linearity($R^2=0.997{\sim}0.999$), and comparison study(r=0.977~0.999) with other equipment was acceptable for all tested items. The results of evaluation for the Toshiba-120FR autochemical analyzer showed that this equipment could be used as an alternative to other equipment.

• 한국멀티미디어학회논문지
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• 제24권3호
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• pp.431-439
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• 2021

Since the sensor nodes are randomly arranged in the region of interest, it may happen that the sensor network area is separated or there is no sensor node in some area. In addition, after the sensor nodes are deployed in the sensor network, a coverage hole may occur due to the exhaustion of energy or physical destruction of the sensor nodes. The coverage hole can greatly affect the overall performance of the sensor network, such as reducing the data reliability of the sensor network, changing the network topology, disconnecting the data link, and worsening the transmission load. Therefore, sensor network coverage hole recovery has been studied. Existing coverage hole recovery studies present very complex geometric methods and procedures in the two-step process of finding a coverage hole and recovering a coverage hole. This study proposes a method for discovering and recovering a coverage hole in a sensor network, discovering that the sensor node is a boundary node by itself, and determining the location of a mobile node to be added. The proposed method is expected to have better efficiency in terms of complexity and message transmission compared to previous methods.

• 환경위생공학
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• 제18권3호통권49호
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• pp.21-26
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• 2003

The generation of waste cable has been continuously increased as a production of electrical and communication media are extended. The current recovery methods, such as mechanical peeling, incineration, solvent extraction and pyrolysis, seems inadequate because they are either hard to apply in some cases or environmentally unacceptable. It has been shown that copper can be effectively separated from the jelly filled type cables using a soybean oil treatment method. As a result, jelly compound is vanished from the wire by soybean oil bath and waste wires are separated copper and PE by the mechanical chipper. This is a more environmentally friendly method than burning, and considerably faster than Stripping.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
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• pp.597-599
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• 1999

Triply encoded HTIS(hadamard transform imaging spectrometer) is a system which applies the grill spectrometer to the HTIS. we consider a nonideality of mask transparent characteristic in estimating spectrum. Triply encoded system increases the SNR(signal to noise ration) by multiplexing effect. In this paper, we suggest an advanced $T^{-1}$ method for spectrum recovery. Then, we proved the superiority of the suggested method by comparing the average MSE(mean square error) of the other recovery methods.

• 한국환경과학회지
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• 제12권1호
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• pp.81-86
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• 2003

The study was carried out to evaluate the new analytical method of phthalate esters(diethylphthalate, di-n-butylphthalate, butylbenzylphthalate, bis(2-ethylhexyl)phthalate), one of the endocrine disruptors, which were performed by GC/MS-SIM(selected ion monitoring). The phthalate esters were extracted from water samples using solid-phase extraction on $C_{18}$ columns. It investigated that the extraction recovery rate of phthalate esters with different solvents and solvent volume. The optimal solvent was dichloromethane and proper volume of dichloromethane for recovery of phthalate esters was 4 mL. There were good linearities(above $R^2$=0.9975) in the range 0.01~0.50mg/L, and the detection limits were below 0.01~0.03$\mu\textrm{g}$/L. The recovery rates, RSD and MDLs for phthalate esters were 80~114%, 5.0~8.1% and 0.03~0.11$\mu\textrm{g}$/L, respectively. This method shows a good precision of phthalate esters.