• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.5
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• pp.45-51
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• 2007

This study was carried out to investigate various heavy metal contents in packaging papers by pre-treatments for ICP-ES (Inductively Coupled Plasma Emission Spectrometry) analysis. Pre-treatment methods of heavy metals in this study include extraction, migration and decomposition methods (dry ashing, $HNO_3-HClO_4-HF,\;HNO_3,\;and\;H_2SO_4-HNO_3$). Test results were compared with conventional extraction (water) and migration (3% acetic acid) methods. The five representative heavy metals (Cd, As, Pb, Cr and Hg) were analyzed. For Cd, Hg, and As, the results were below detection limit of the instrumental technique. It was considered that the migration test was a better method compared to extraction test, but all the decomposition methods showed much higher detection values than the extraction or migration test. In case of recycled corrugated containers, 3% acetic acid solution extracted about 25% of chromium and 30% of lead compared to the content by decomposition methods. Among all decomposition methods, the nitric acid - perchloric acid - hydrofluoric acid treatment brought a slightly higher detection value than others, but there was no significant difference among them except sulfuric acid - nitric acid method.

• Resources Recycling
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• v.17 no.3
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• pp.29-34
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• 2008

Solvent extraction behaviors of iron(III) from chloride solution at high ionic strength condition between Alamine336 and TBP were compared by using MaCabe-Thiele diagram. Extraction isotherms of iron by the two extractants were obtained by calculating the equilibrium concentrations of iron in both phases from the initial extraction conditions. In calculating the equilibrium concentration of iron, chemical equilibria in the aqueous phase and mass balance together with the solvent extraction reaction were considered. MaCabe-Thiele diagram of iron by 1M Alamine336 indicated that two extraction stages could lead to complete extraction of 0.5M iron from 3M HCl solution at an A/O ratio of 6/5. The extraction power of 1M Alamine336 was found to be the same as 2-3M TBP. MaCabe-Thiele diagram together with the physical properties of the two extractants indicated that Alamine336 is superior to TBP in extracting ferric iron from chloride solution.

• The Journal of the Korean dental association
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• v.58 no.9
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• pp.564-572
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• 2020

Implant treatment has long been established as the main stream for the recovery of lost teeth. Implant therapy, which began to be practiced under the concept of osseointegration, was performed on the completely healed bone, but implant placement immediately after extraction, which began to be introduced in the 1970s, began to become a widely used treatment modality since the 2000s. However, as with all other procedures, immediate implant placement is not omnipotent. If you are obsessed with the obsession that you need to provide quicker implant treatment to the patients, and if you do it as if you are being chased by time, it is the immediate implant placement that can lead to various embarrassing situations. In this article, to reduce complications, the author will look at some issues that need to be considered when placing implants immediately after extraction.

• Smart Media Journal
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• v.7 no.4
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• pp.79-89
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• 2018

In recent years, falls among elderly people have gained serious attention as a major cause of injuries. Falls often lead to fatal consequences due to lack of prompt response and rescue. Therefore, a more accurate fall detection system and an effective feature extraction technique are required to prevent and reduce the risk of such incidents. In this paper, we proposed an efficient feature extraction technique based on multiple sliding windows and validated it through a series of experiments using supervised learning algorithms. The experiments were conducted using the public datasets obtained from tri-axial accelerometers. The results depicted that extraction of the feature from adjacent sliding windows led to high accuracy in supervised machine learning-based fall detection. Also, the experiments conducted in this study suggested that the best accuracy can be achieved by keeping the window size as small as 2 seconds. With the kNN classifier and dataset from wearable sensors, the experiments achieved accuracy rates of 94%.

• Kosin Medical Journal
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• v.33 no.3
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• pp.396-401
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• 2018

Extraction of old pacemaker leads remains a complex procedure owing to fibrotic encapsulation and lead adhesions. We report a case of extraction of 15-year-old pacemaker leads by weight and pulley method. A 81-year-old man presented with exposed pacemaker leads out of body with purulent discharge from a pacemaker insertion site. He inserted DDD (dual chamber pacing, dual chamber sensing dual function) pacemaker implantation 15 years ago for SSS. Previously pacemaker battery was removed 3 years ago due to recurrent infection of pacemaker scar site. We extracted the pacemaker leads by weight and pulley method successfully without any complications.

• Journal of Periodontal and Implant Science
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• v.48 no.4
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• pp.236-250
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• 2018

Purpose: Resorption of the alveolar bone is an unavoidable consequence of tooth extraction when appropriate alveolar ridge preservation (ARP) measures are not taken. The objective of this trial was to test the hypothesis that dimensional changes in the alveolar bone after tooth extraction would be reduced by inserting an equine collagen membrane and a collagen cone to fill and seal the alveolus (as ARP), in comparison to extraction with untreated alveoli. Methods: In this randomized clinical trial, 31 patients were directly treated with the collagen material after extraction of a tooth from the maxilla (the ARP group). Twenty-nine patients served as the control group. After extraction, no further treatment (i.e., no socket preservation measures) was performed in the control group. Changes in the alveolar process immediately after extraction and after an 8 (${\pm}1$)-week healing period were evaluated 3-dimensionally. Blinded analyses were performed after superimposing the data from the digitalized impressions and surfaces generated by cone-beam computed tomography. Results: Both the ARP and control groups showed a reduction of bone in the alveolar area after tooth extraction. However, significantly less bone resorption was detected in the clinically relevant buccal region in the ARP group. The median bone reduction was 1.18 mm in the ARP group and 5.06 mm in the control group (P=0.03). Conclusions: The proposed hypothesis that inserting a combination material comprising a collagen cone and membrane would lead to a difference in alveolar bone preservation can be accepted for the clinically relevant buccal distance. In this area, implantation of the collagen material led to significantly less alveolar bone resorption. German Clinical Trials Register at www.drks.de, DRKS00004769.

• Bulletin of the Korean Chemical Society
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• v.25 no.8
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• pp.1133-1136
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• 2004

The need for highly reliable methods for the determination of trace metals is recognized in analytical chemistry and environmental science. A method based on the cloud-point extraction (CPE) technique for the trace analysis of Pb and Cu in water samples is described in this study. The analytes in the initial aqueous solution are complexed with pyrogallol, and 0.1%(w/v) Triton X-114 is added as surfactant. Following phase separation at $50^{\circ}C$, based on the cloud point of the mixture and dilution of the surfactant-rich phase with acidified methanolic solution, the enriched analytes are determined by flame atomic absorption spectrometry. After optimization of the complexation and extraction conditions, the enrichment factors of Pb and Cu were found to be 72 and 85, respectively. Under optimum conditions, the preconcentration of 60 mL of samples in the presence of 0.1%(w/v) Triton X-114 permitted the detection of 0.4 ${\mu}gL^{?1}$ of Pb and 0.05 ${\mu}gL^{?1}$ of Cu. The proposed method was applied successfully to the determination of Pb and Cu in water samples.

• Journal of the Korea Society of Computer and Information
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• v.24 no.1
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• pp.85-92
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• 2019

In this paper, we propose a efficient feature point extraction method that can solve the problem of performance degradation by introducing a preprocessing process when extracting feature points by utilizing the characteristics of 360-degree realistic media. 360-degree realistic media is composed of images produced by two or more cameras and this image combining process is accomplished by extracting feature points at the edges of each image and combining them into one image if they cover the same area. In this production process, however, the stitching process where images are combined into one piece can lead to the distortion of non-seamlessness. Since the realistic media of 4K-class image has higher resolution than that of a general image, the feature point extraction and matching process takes much more time than general media cases.

• Analytical Science and Technology
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• v.37 no.5
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• pp.295-305
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• 2024

5-Hydroxymethyl-2-furaldehyde (5-HMF) is considered one of the main quality indexes of various food products. Its metabolism in humans can potentially lead to carcinogenic compounds. Metallic ions such as Zn, Mg, Mn, and Fe have been reported to enhance 5-HMF formation. Recently, studies on adsorbents that can extract specific organic and inorganic substances with one adsorbent have been conducted. However, simultaneous analysis of organic and inorganic materials typically requires distinct pre-treatment and analytical methods, which increase a lot of labor and cost. In this study, hybrid imprinted polymer (HIP) by mixing 5-HMF imprinted polymer (FIP) and zinc ion imprinted polymer (ZIIP) were generated to extract two analytes, Zn ion and 5-HMF, simultaneously. Physicochemical characterization of HIP was conducted by Fourier-transform infrared spectroscopy, scanning electron microscopy, and sorption tests. Extraction conditions including adsorbent mixing ratio, adsorbate mixing range, and equilibrium time were optimized. Freundlich adsorption model was as the best-fitting isotherm model to elucidate the adsorption mechanism. Affinity of Zn ion and 5-HMF on HIP was superior to non-HIP. In conclusion, HIP showed reasonable feasibility that could be used as an adsorbent to be used for simultaneous extraction of organic and inorganic compounds present in the sample.

• Journal of Soil and Groundwater Environment
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• v.15 no.5
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• pp.23-31
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• 2010

For an efficient remediation of Pb-contaminated soil (S-1) in a clay shooting range, a soil washing test was performed with mineral acid, organic acid, chelating agent, and chloride. The Pb extraction efficiency of extractant (0.1 M) used in the washing test showed the order of HCl > $Na_2$-EDTA > NTA > DTPA > citric acid > malic acid > succinic acid > acetic acid > $CaCl_2$ > $MgCl_2$, for S-1 soil. As compared to initial Pb concentration, extraction efficiency by the concentration of extractant was 93.35%, 80.80%, 73.92%, and 24.57% in S-1 soil for HCl (0.5 M, pH 1.10), $Na_2$-EDTA (0.01 M, pH 3.99), citric acid (0.5 M, pH 1.27), and $MgCl_2$ (0.1 M, pH 8.82), respectively. S-1 soil had 56.83% of residue form and 43.17% of non-residue form (18.04% of exchangeable form), respectively. Although the concentrations of these fractions sharply decreased after HCl washing, since the exchangeable forms with relatively large mobility are still distributed as high as 18.78% (to Pb total content in residual soils) in S-1 soil, it is necessary to devise a proper management plan for residual soils after soil washing application.