• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.350-353
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• 2004

in order to develop a new technique for the removal of arsenic compoundsfrom acidified water, the removal of arsenic compounds by an acidophilic moss, Jungermannia vulcanicola Steph. was investigated in this study. The result of vial tests for arsenic removal is dependent on the biological activity of moss. The presence of phosphate inhibited the arsenic removal. And the acclimatization of moss by the media containing arsenic increased the its capability of arsenic remova.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.2
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• pp.167-173
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• 2004

Fouling of heat exchangers is generated by water-borne deposits, commonly known as foulants including particulate matter from the air, migrated corrosion produces; silt, clays, and sand suspended in water; organic contaminants; and boron based deposits in plants. The fouling is known to interfere with normal flow characteristics and reduce thermal efficiencies of heat exchangers. This paper describes the fouling analysis technique developed in this study which can analyze the thermal performance for heat exchangers and estimate the future fouling variations. To develop the fouling analysis technique fur heat exchangers, fouling factor was introduced based on the ASME O&M codes and TEMA standards. For the purpose or verifying the fouling analysis technique, the routing analyses were performed for four heat exchangers in several nuclear power plants; two residual heat removal heat exchangers of the residual heat removal system and two component cooling water heat exchangers of the component cooling water system.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.34-37
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• 2002

In this study, electrochemical characteristics variation and removal efficiency with initial pH and mineral compositions during electrokinetic remediation of lead contaminated soils were investigated. Test results showed that heavy metal transportation affected by soil characteristics and electrochemical characteristics varied during electrokinetic remediation. Therefore, in the application of enhanced electrokinetic remediation technique to increase removal efficiency, discrete selection of enhanced technique with characteristics of targeted soil were needed.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.40-52
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• 1998

Among the non-traditional machining methods, Abrasive waterjet machining process shows big promise in drilling difficult-to-machine materials due to its numerous advantages such as absence of heat affect zone and thermal distortion. Acoustic emission signal technique is used to understand about material removal mechanisms during abrasive waterjet drilling process. More information about the drilling process is derived through frequency decomposition of auto regressive moving average modeling representing acoustic emission signals.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.487-491
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• 2009

The inverse halftoning is processing to restore the image made binary to former step image. There are smoothing and gaussian filtering in the technique so far. However, there are still a lot of insufficient points in past inverse halftoning. The removal of the noise and the edge enhansment are closely related in inverse halftoning. It is difficult to do both the noise rednctiom and the edge enhansment in high accuracy at the same time in the technique so far. The technique that can achieve both the removal of the noise and the emphasis of Edge at the same time is expected as future tasks. Then, it was tried to apply the Kalmann filtering to inverse halftoning. In the actual experiment, the effectiveness of the application of the Kalmann filtering to inverse halftoning comparing it with the technique so far was shown.

• Environmental Engineering Research
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• v.21 no.3
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• pp.304-310
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• 2016

Removal of arsenic (As) from soil aggregates with particle sizes of > 2.0, 2.0-0.25, 0.25-0.053, < 0.053 mm by soil washing of $KH_2PO_4$ and the kinetics of As releasing from soil aggregates were investigated. Effects of $KH_2PO_4$ concentration, ratio of liquid/soil and washing duration on the removal were fully explored. The results showed that the high As removal was obtained in > 2 mm aggregates (48.56%) and < 0.053 mm aggregates (42.88%) under the optimum condition ($KH_2PO_4$ concentration of 0.1 mol/L, and liquid/soil ratio (10 mL/g) for 360 min). 62.82% of As was extracted from aggregates with size less than 0.25 mm. Only 11.88% was contributed by the large aggregates (> 2.0mm). Using $KH_2PO_4$ washing, it was also found that extracted As is mainly in form of either specifically sorbed As or As associated with oxides of Fe and Al. Elovich model can describe the removal process of As more precisely than Two-constant kinetic models. The optimum washing conditions and removal process is also applied to bulk soil. This technique in this study is reliable, cost-effective and offers a great potential for practical application in soil remediation.

• Advances in environmental research
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• v.12 no.2
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• pp.77-93
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• 2023

The water can be contaminated by natural sources or by industrial effluents. One such contaminant is fluoride. Fluoride contamination in the water environment due to natural and artificial activities has been recognized as one of the major problems worldwide. Among the commonly used treatment technologies applied for fluoride removal, the adsorption technique has been explored widely and offers a highly efficient simple and low-cost process for fluoride removal from water. This review paper the recent developments in fluoride removal from surface water by adsorption methods. Studies on fluoride removal from aqueous solutions using various carbon materials are reviewed. Various adsorbents with high fluoride removal capacity have been developed, however, there is still an urgent need to transfer the removal process to an industrial scale. Regeneration studies need to be performed to more extent to recover the adsorbent in field conditions, enhancing the economic feasibility of the process. Based on the review, technical strategies of the adsorption method including the Nano-surface effect, structural memory effect, anti-competitive adsorption and ionic sieve effect can be proposed. The design of adsorbents through these strategies can greatly improve the removal efficiency of fluoride in water and guide the development of new efficient methods for fluoride removal in the future. This paper describes brief discussions on various low-cost adsorbents used for the effective removal of fluoride from water.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.4
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• pp.464-472
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• 1994

Surgical removal of the submandibular gland via intraoral approach was performed. The surgical procedure to be used for removal of submandibular gland had been performed via extraoral approach for many centuries. Disadvantages of extraoral technique are the esthetic distress due to an external scar, residual inflammation in Wharton's duct, and neurological complications. Indications of intraoral approach are unlimited in surgical cases of submandibular gland. Advantages of intraoral approach are esthetic satisfaction due to no remaining scars, preservation of adjacent anatomical structures and preservation of lower facial contour. This paper describes the surgical technique of the submandibular gland excision through an intraoral approach and variable incision lines tried. In 7 cases, excellent results were obtained after removal of the submandibular gland through an intraoral approach.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.210-214
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• 2002

In this study, the coupled effect of electrokinetic and ultrasonic remediation technology was investigated for removing of heavy metal and organic matter at the same time. The laboratory tests were conducted using specially designed and fabricated electrokinetic and ultrasonic devices. The electrokinetic technique was applied to remove mainly the heavy metal and the ultrasonic technique was applied to remove mainly organic substance in contaminated soil. Diesel fuel and Cd were used as a surrogate contaminant for this test. A series of laboratory experiments involving electrokinetic and electrokinetic+ultrasonic flushing test were carried out. An increase in permeability and contaminant removal rate was observed in electrokinetic+ultrasonic flushing test.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.2
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• pp.66-72
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• 2006

The old technique of sandblasting which has been used for paint or scale removing, deburring and glass decorating has recently been developed into a powder blasting technique for brittle materials, capable of producing micro structures larger than $100{\mu}m$. In this paper, we studied on the predictive modeling of material removal and surface roughness in powder blasting of glass by design of experiments. The surface characteristics and surface shape of powder blasted glass surface were tested under different blasting parameter. Finally, we proposed a predictive model for powder blasting process, and compared with experimental results.