• Journal of Industrial Technology
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• v.36
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• pp.83-88
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• 2016

In this study, a series of experiment was carried to improve dewaterability of the sludge produced in a treatment plant, located in Hongcheon, Gangwondo, which has been treating municipal wastewater and livestock wastewater. Optimum sludge mixing ratio and the amount of sludge conditioner were determined. As sludge conditioners, alum and ferric salt were selected and tested. For the measurement of sludge dewaterability, capillary suction time(CST) and the specific resistance were measured, The specific resistance was detemined by running a series of Buchner Funnel Test. Mixing the two sludges at a 50:50 ratio with the addition of 20 mL alum gave the best results in terms of dewaterability. The moisture content decreased by 2% at this condition.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.15 no.3
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• pp.105-111
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• 2009

In this work, source reduction of poly ethylene terephthalate (PET) packaging are discussed as aspect of sustainability, such as reuse, refill and recycling through the various treatment methods and historical studies for municipal solid waste (MSW) disposal. Since PET has good chemical, physical and mechanical properties, and provides good oxygen and carbon dioxide barrier properties, PET is one of the most widely used thermoplastic polyester in the U.S. and around the world. As the demand for non-renewable PET is increasing, several approaches have been developed to meet economical feasibility and environmental responsibility without degrading material performance. Several companies, such as Coca-Cola Co., Easterform Packaging Co. and Kraft, have tried to develop lightweight PET bottle, and some of lightweight PET bottles are already commercialized. Reuse and refilling for PET container is well developed in Europe, such as Denmark, German and Netherland by supportive legislation and policies. Recycling process is the best way to economically reduce PET waste. In consequence, advanced technique and further development must be provided due to increasing PET packaging waste.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.6
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• pp.429-433
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• 2013

PTFE composites for use of microwave substrate were fabricated by impregnation and heat treatment fabrication with glass fabric. This study shows dielectric properties such as dielectric constant and loss can be controlled by thickness of PTFE composite with change of pressure condition in heating press process. The dielectric constant of the PTFE composites has decreasing tendency as given higher pressure condition. The dielectric loss has similar result too. Especially, the case of the dielectric loss was affected by the condition of pressure at heating press and had the best performance under 3 MPa. In order to see the reason why thickness conditions make different, their microstructures were also observed.

• Journal of the Korean Applied Science and Technology
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• v.13 no.2
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• pp.47-53
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• 1996

The procedure to prepare an acrylic emulsion water repellents by blending of arcylic copolymer, activated polyethylene, wax, and emulsifiers was published in the previous paper. After the treatment of the prepared water repellents on a cotton fabrics with and without textile finishing resin, washability, contact angle, tearing strength, and crease recovery were tested. As the result, there were remarkable improvements in physical properties. Proper curing temperature of the synthesized water repellents impellents was $150^{\circ}C$ : proper using concentration was 5wt% : sodium acetate was the best catalyst for water repellents among the used, and proper concentration was 1.0wt%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.6
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• pp.459-466
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• 2000

For the applications in the ultra-large-scale-integration (ULSI) metallization processing copper thin films have been prepared by metal organic chemical vapor deposition (MOCVD) technology on TiN/Si substrates. The films have been deposited with varying the experimental conditions of substrate temperatures and copper source vapor pressures. The films were then annealed in a vacuum condition after the deposition and the annealing effect to the electrical conductivity of the films was measured. The grain size and the crystallinity of the films were observed to be increased by the post annealing and the electrical conductivity was also increased. The best electrical property of the copper film was obtained by in-situ annealing treatment at above 40$0^{\circ}C$ for the sample prepared at 18$0^{\circ}C$ of the substrate temperature.

• Journal of Industrial Technology
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• v.29 no.B
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• pp.89-94
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• 2009

The dyeing sludge is the major waste generated in Banwol & Sihwa Industrial Complex. The Purpose of this study is to develop BAT (Best available technique) for the treatment and recycling of dyeing sludge. The dyeing sludge was carbonized and the product was tested physical properties and chemical chracterizations and also analyzed chemical compositions. From the test results we expect that the products can be used as adsorbent for the removal of order in the poultry farm and cattle shed. The feasibility of other methods such as manufature of RDF and cement etc. were also studied.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.241-244
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• 2002

The dependence of NiSi properties such as sheet resistance and cross-sectional profile on the dopants was characterized. There was little difference of sheet resistance between various dopants such as As, p, BF2 and B just after R'n formation of NiSi. However, the NiSi properties showed strong dependence on the dopants when thermal treatment was applied after RTf formation. BFa .implanted silicon was the best stable property while As implanted one was the worst. The main reason of the excellence property of BF2 sample is believed to be the retardation of Ni diffusion by the F. Therefore, retardation of Ni diffusion is very desirable fur high performance NiSi technology.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.172-179
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• 1999

As the martensite structure cause fracture failure during drawing from 5.5mm rod to 3.05mm dia. wire without additional heat treatment, the optium cooling condition to inhibit the occurrence of martensite was investigated. In order to get SAE9254+V quality, the effects of alloying element, vanadium on the mechanical properties were investigated. Based upon CCT and TTT curves and the results form cooling test in mill, optimun cooling was found in the condition of the laying head temp of 780$^{\circ}C$ and of the conveyor speed at 0.15m/sec with the whole cover closed. The wire rods produced under the condition showed the best mechanical properties of 120kg/$\textrm{mm}^2$ in TS and 50% in RA, having an excellent drawability. In vanadium added steels, tensile strength was improved without degrading elongation and charpy impact value. That means the strengthening by vanadium is mainly due to the grain refinement by the fine precipitates during tempering process.

• Proceedings of the KIEE Conference
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• 2005.10c
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• pp.223-225
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• 2005

This paper presents a novel prototype of a current source resonant inverter using insulated gate bipolar transistors for driving a streamer reactor, streamer generation technology has been recognized as one of the best methods for water treatment, disinfection, industrial wastes utilization, and so on. However, some technological difficulties related to efficient streamer production have been significant problems restricting streamer usage in the industrial plants. Introduced in this paper is a pulse density modulated high frequency inverter for a plasma generate, which is developed with the aim to improve power conversion and control characteristics of the streamer reactor by using advances in power electronic technology. The developed system implements the feedforward control-based pulse density modulation control scheme with pulse width modulation feedback control strategy to compensate temperature and other environmental influences on streamer discharge.

• Journal of Electrochemical Science and Technology
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• v.15 no.1
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• pp.152-160
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• 2024

In this study, ZnCo₂O₄ nanoparticles were synthesized via the coprecipitation method using different annealing temperatures from 200℃ to 800℃. By varying the treatment temperature, the morphology changed from amorphous to tetragonal, and finally to polygonal particles. As temperature increased, the sizes of the nanoparticles also changed from 5 nm at 200℃ to approximately 500 nm at 800℃. The fabricated material was used to modify the working electrode of a screen-printed carbon electrode (SPE), which was subsequently used to survey the detection performance of the antibiotic, chloramphenicol (CAP). The electrochemical results revealed that the material exhibits a good response to CAP. Further, the sample that annealed at 600℃ displayed the best performance, with a linear range of 1-300 μM, and a limit of detection (LOD) of 0.15 μM. The sensor modified with ZnCo₂O₄ also exhibited the potential for utilitarian application when the recovery in a real sample was above 97%.