• Title/Summary/Keyword: Selective extraction

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Expanded Object Localization Learning Data Generation Using CAM and Selective Search and Its Retraining to Improve WSOL Performance (CAM과 Selective Search를 이용한 확장된 객체 지역화 학습데이터 생성 및 이의 재학습을 통한 WSOL 성능 개선)

  • Go, Sooyeon;Choi, Yeongwoo
    • KIPS Transactions on Software and Data Engineering
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    • v.10 no.9
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    • pp.349-358
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    • 2021
  • Recently, a method of finding the attention area or localization area for an object of an image using CAM (Class Activation Map)[1] has been variously carried out as a study of WSOL (Weakly Supervised Object Localization). The attention area extraction from the object heat map using CAM has a disadvantage in that it cannot find the entire area of the object by focusing mainly on the part where the features are most concentrated in the object. To improve this, using CAM and Selective Search[6] together, we first expand the attention area in the heat map, and a Gaussian smoothing is applied to the extended area to generate retraining data. Finally we train the data to expand the attention area of the objects. The proposed method requires retraining only once, and the search time to find an localization area is greatly reduced since the selective search is not needed in this stage. Through the experiment, the attention area was expanded from the existing CAM heat maps, and in the calculation of IOU (Intersection of Union) with the ground truth for the bounding box of the expanded attention area, about 58% was improved compared to the existing CAM.

Communication performance of selective combining frequency diversity with maximum likelihood estimation in underwater multipath frequency selective channels (수중 다중경로 주파수 선택적 채널에서 최대우도추정을 적용한 선택적합성 주파수 다이버시티의 통신 성능)

  • Lee, Chaehui;Park, Kyu-Chil;Park, Jihyun
    • The Journal of the Acoustical Society of Korea
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    • v.41 no.2
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    • pp.143-149
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    • 2022
  • In this paper, we evaluate the underwater frequency diversity communication performance of Selective Combination (SC) using Maximum Likelihood Estimation (MLE). In an underwater multipath frequency selective channel, destructive interference fading due to delay spread of a received signal affects the increase in error and Signal to Noise Ratio (SNR) variability of an underwater acoustic communication. Selective Combination frequency diversity using a single sensor is applied as a transmission performance improvement technique according to the frequency selectivity of a channel. In the sea experiment applying MLE for SC decision value extraction, we evaluate the performance of SC frequency diversity and MLE-SC frequency diversity. In experiment result, we confirm through experiment that the Bit Error Rate (BER) is relatively lower when the decision value extracted through MLE-SC is applied than when the SC decision value is fixed.

Studies on Solvent Extraction Using Salphen for Separative Determination of Trace Fe(II) and Fe(III) in Water Samples

  • Kim, Eun-Jook;Kim, Young-Sang;Choi, Jong-Moon
    • Bulletin of the Korean Chemical Society
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    • v.29 no.1
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    • pp.99-103
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    • 2008
  • Solvent extraction using salphen as a ligand has been investigated for the selective separation and determination of trace Fe(II) and Fe(III). A salphen ligand was synthesized, and solvent extraction variables, such as solution pH, the concentration of salphen, the type of organic solvent, auxiliary agents, oxidants and the effect of interference were optimized. Salphen is stable at pH 3-4, and Fe(III)-salphen complexes can be selectively extracted into an MIBK(4-methyl-2-pentanone) phase from an aqueous solution within this pH range. For the determination of the total amount of iron in 100 mL of aqueous solution, Fe(II) ions were completely oxidized using 0.05 mL of 3.5% H2O2 without side reactions. To evaluate its applicability, the proposed method was applied to determine trace Fe(II) and Fe(III) in several kinds of water samples. Reproducible results were obtained with RSD of less than 3.0%, and the recoveries for this reliability were obtained with 91-112%.

High throughput automated 96-well solid-phase extraction and liquid chromatography-tandem mass spectrometric analysis of beraprost in human plasma

  • Chang, Kyu-Young;Kim, Ho-Hyun;Lee, Hee-Joo;Lee, Kyung-Ryul
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.224.1-224.1
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    • 2003
  • A sensitive and selective liquid chromatographic method coupled with tandem mass spectrometry (LC-MS/MS) was developed for the determination of beraprost in human plasma. Plasma samples were transferred into 96-well OASIS HLB extraction plate using an automated sample handling system and the drugs were eluted with methanol. The eluents were then evaporated and reconstituted with water. All sample transfer and solid-phase extraction (SPE) was automated through the application of both the PerkinElmer MultiPROBE II HT and TOMTEC Quadra 96 workstation. (omitted)

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Improving the Charge Extraction of Organic Photovoltaics by Controlling the PCBM Overlayer/Active-Layer Interface (PCBM Overlayer/활성층 계면 제어를 통한 유기 태양전지의 전하 추출 개선)

  • Soonho Hong;Haechang Jeong;Hoseung Kang;Sunyoung Sohn
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.37 no.4
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    • pp.451-456
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    • 2024
  • Organic photovoltaic (OPV) devices have attracted attention due to their high efficiency and simple manufacturing process. Applying an overlayer to OPV devices is one way to improve their performance because it can improve charge extraction and suppress vertical phase separation. In addition, dichloromethane (DCM) was used as an orthogonal solvent to minimize the effect on other layers. However, an coating problems due to the use of DCM were found, which affects surface morphology as rough or peeling. Additional research efforts are needed to solve these problems, and optimal results are expected to be obtained by utilizing various buffer layers or selective organic solvents.

Organic Acid Extraction of Fluoride from Antarctic Krill Euphausia superba

  • Xie, Cheng Liang;Kim, Han Soo;Shim, Kil Bo;Kim, Yeon Kye;Yoon, Na Yeong;Kim, Poong Ho;Yoon, Ho Dong
    • Fisheries and Aquatic Sciences
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    • v.15 no.3
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    • pp.203-207
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    • 2012
  • The amount of fluoride removed from Antarctic krill via organic acid extraction depends on the extraction time, concentration, extraction volume, and the nature of the acid itself. The fluoride content in Euphausia superba was determined by measuring the concentration of fluoride ion in acidic extracts using an ion-selective electrode. The best results were obtained by adding 50 mL of 0.01 M citric acid to 0.3-0.5 g of krill and extracting for 5 min. Under these conditions, recoveries of fluoride from frozen whole krill and krill meat were 95.6-99.5% and 97.5-101.3%, respectively. The dry basis fluoride contents of krill by-product, krill meat and the boiled krill were 705, 298, and 575 ppm, respectively. These levels were significantly reduced by citric acid extraction.

Selective transport of Cadmium by PVC/Aliquat 336 polymer inclusion membranes (PIMs): the role of membrane composition and solution chemistry

  • Adelung, Sandra;Lohrengel, Burkhard;Nghiem, Long Duc
    • Membrane and Water Treatment
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    • v.3 no.2
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    • pp.123-131
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    • 2012
  • This study investigated the extraction and stripping performance of PIMs consisting of PVC and Aliquat 336. Extraction and stripping of three representative heavy metals - namely $Cd^{2+}$, $Cu^{2+}$, and $Zn^{2+}$ - by the synthesized membranes were evaluated as a function of sodium chloride concentration and under different stripping solutions (0.01 M $HNO_3$, Milli-Q water, 0.01 M HCl and 0.01 M NaOH), respectively. Results reported here indicate that the formation of negatively charged metal chloride complex species was responsible for the extraction of the target metal to PIMs. Experimental results and thermodynamic modeling of the speciation of chloro metal complexes further confirm that the extraction selectivity between $Cd^{2+}$, $Cu^{2+}$ and $Zn^{2+}$ can be controlled by regulating the chloride concentration of the feed solution. An acidic solution without any chloride was the most effective stripping solution, followed by Milli-Q water, and a diluted hydrochloric acid solution. On the other hand, the stripping of metals from PIMs did not occur when a basic stripping solution was used.

Advanced Lipid Extraction Method for the Determination of the Phospholipase D Activity

  • Yon, Chang-Suek;Lee, Min-Ho;Oh, Doo-Yi;Kim, Dal-Soo;Lee, Ki-Sung;Han, Joong-Soo
    • Archives of Pharmacal Research
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    • v.26 no.6
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    • pp.478-481
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    • 2003
  • Phospholipase D is a ubiquitous enzyme that plays an important role in various lipid mediated cellular signaling pathways and produces rare phospholipids, phosphatidylethanol or phosphatidylbutanol, instead of phosphatidic acid with unique catalytic activity transphosphatidylation in the presence of primary alcohols. The reaction products, phosphatidylethanol or phosphatidylbutanol are used as markers of in vitro phospholipase D activity in many studies. For the sensitive detection of the phospholipase D products, we developed an advanced lipid extraction method that facilitates recovery of the compounds. With the new method, the activity change of phosaholipase D by agonists could be detected more easily and the recovery rate was also increased. The increase of detected enzyme activity change was about double fold compared to the conventional lipid extraction method. This method provides selective force for the phospholipase D products in the extraction procedure.

Road Extraction by the Orientation Perception of the Isolated Connected-Components (고립 연결-성분의 방향성 인지에 의한 도로 영역 추출)

  • Lee, Woo-Beom
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.1
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    • pp.75-81
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    • 2012
  • Road identification is the important task for extracting a road region from the high-resolution satellite images, when the road candidates is extracted by the pre-processing tasks using a binarization, noise removal, and color processing. Therefore, we propose a noble approach for identifying a road using the orientation-selective spatial filters, which is motivated by a computational model of neuron cells found in the primary visual cortex. In our approach, after the neuron cell typed spatial filters is applied to the isolated connected-labeling road candidate regions, proposed method identifies the region of perceiving the strong orientation feature with the real road region. To evaluate the effectiveness of the proposed method, the accuracy&error ratio in the confusion matrix was measured from road candidates including road and non-road class. As a result, the proposed method shows the more than 92% accuracy.

A Study on Reactive Extraction of Citric Acid in Citric-acetic-lactic Acid System (구연산-초산-유산계에서 구연산의 반응추출에 관한 연구)

  • Lee, Han-Seob;Kang, An-Soo
    • Applied Chemistry for Engineering
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    • v.5 no.1
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    • pp.90-98
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    • 1994
  • For elucidation of various parameters' effects on the reactive extraction of citric acids, citric-acetic-lactic acid system with various carriers, diluents, and modifiers were investigated. Carries used were secondary amines, tertiary amines, and solvation extract. Dileunts were n-butylacetate, methoisobutylketon(MIBK), kerosine, and xylene. Modifiers were TBP and isodecanol. The effects of temperature and pH in aquous phase were studied, and equilibrium constants for the reactive extraction were obtained. The re-extraction was performed by alkali solutions such as NaOH, $Na_2CO_3$, and $K_2HPO_4$. Based on the experiment Di-isotridecylamine(secondary amine ) gave higher degree of extraction and more selective than other extractants tested for the extraction of citric acid. N-butylacetate and TBP showed heigher performance for a diluent and modifier, repetitively. The degree of extraction was getting better with decreasing the pH in the aquous phase and the temperature of extraction system. The degree of re-extraction was getting higher with decreasing basicity in the stripping phase and the system temperature, and with increasing the concentration of alkali solution.

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