• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.4
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• pp.103-111
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• 2002

The purpose of this study is to investigate influence of NaCl precisely in recycling process of food waste and in places where food waste compost is used, because NaCl with food waste has caused concerns of adverse effects in the process of food waste recycling and in plates where final products is used. The influence of NaCl in composting was measured through temperature, concentration of carbon dioxide ($CO_2$) and pH. NaCl didn't cause bad effects until 1%(wet base) of NaCl concentration for composting, showed adverse effects gradually at 2% and 3% and affected composting deeply at 6%. The influence of NaCl in composting was insignificant until 3% of NaCl concentration but decomposing efficiency of organic compounds was interfered with more than 3%. NaCl concentration has to be maintained less than 1%(wet base) to minimize adverse effects of NaCl in composting however NaCl concentration with food waste used in real composting facilities is so lower than 1 %(wet base) that the bad influence in food waste composting is slight. Compost(final product) was collected from real food waste recycling facilities in A city, S city, K-Gu and S-Gu and controlled NaCl concentration artificially such as 0.5%, 0.8%, 1.2%, 1.6%, 2.0%, 2.5% and 3.0% to investigate influence of NaCl on growth of plants. In results of plant test and pot experiment, according to quality of compost sampled, the influence of NaCl is insufficient until 3% and bad effects appeared clearly more than 3%. The bad effects showed less than 3% because compost sampled was not stabilized fully.

• Resources Recycling
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• v.11 no.2
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• pp.36-44
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• 2002

The waste garnet powder as a raw material for clay bricks was studied its recycling. The physical strength of clay bricks are closely dependent both on the contents of $SiO_2$, $Al_2$$O_3$, and $Fe_2$$O_3$in clay and on the viscosity of it. Although the garnet power has very high contents of $SiO_2$, $Al_2$$O_3$, and $Fe_2$$O_3$, it could not substituted to clay because of its low viscosity. Therefore the substitution of sand with waste garnet powder was considered to influence positively on the strength of clay bricks .Mixing ratios of {clay-sand}, {sand-garnet powder}, and {clay-sand-garnet powder} based on weight were controlled in the production of clay bricks. The properties of clay bricks such as compression strength, moisture absorption, shrinkage, and specific gravity has been evaluated. It was shown that the optimal mixing combination was found to be { clay(50%)-sand(30%)-garnet powder(20%)} as a weight basis. The present study indicated possibilities to produce commercially clay bricks with the waste garnet powder. An economical benefit will be produced in viable in view of recycling waste garnet powder.

• Resources Recycling
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• v.22 no.3
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• pp.28-35
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• 2013

The recycling of the Si/SiC mixture sludge obtained from solar cell industry is very significant, environmentally and economically. The sintering characteristics of Si/SiC mixture sludge was studied for the purpose of recycling. In this study, to understand sintering behavior, SiC content in the Si/SiC mixture was controlled using an air separator. Various Si/SiC mixtures having different SiC contents were sintered using carbon black, clay and aluminum hydroxide as sintering aids. Physical properties of Si/SiC mixture and sintered bodies have been characterized using SEM, XRD, particle size analyzer and apparent density measurement. SEM and particle size analysis result confirmed that the fine particles less than 1 ${\mu}m$ decreased or removed more effectively through the air separator in the case of 95% SiC sample compared than the case of 75% SiC sample or original SiC sample. Further, with addition of the Aluminum Hydroxide, ${\beta}$-cristobalite phase gradually decreased while mullite phase gradually increased. The addition of the carbon black improved the sintering characteristics.

• Resources Recycling
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• v.21 no.1
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• pp.60-65
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• 2012

The Ti-6Al-4V alloys were prepared by recycling of dental Ti pure scraps using vacuum arc melting process, and their physical properties were evaluated the Ti-6Al-4V alloys with different oxygen concentrations. For the preparation of Ti-6Al-4V alloys, Ti pure scraps used for dental implant were utilized as a raw material, and their different oxygen concentrations were ranged from G1 to G4 grade in ASTM standards. It was confirmed that the weight loss of Al in the composition of Ti-6Al-4V alloy could be controlled under the Ar pressure of 875 torr during the melting of alloy. The oxygen concentrations of the Ti-6Al-4V alloys were ranged from 1170 to 3340 ppm. The vickers hardness change of the Ti-6Al-4V alloys showed a similar behavior with that of pure Ti. As a result, we confirmed a possibility of preparation of Ti-6Al-4V alloy by recycling of dental Ti scraps using vacuum arc melting process in this study.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.1
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• pp.51-64
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• 1994

To compost the food garbage with the dry bean curd and sawdust as the bulking agents, the method of high-speed fermentation by the characteristic microorganisms group was applied. The results of experiments are summarized as follows ; 1. Korean food garbage, which is high in water content, is difficult to compost only by microorganism fermentation without the addition of bulking agents such as dry bean curd cake and sawdust. 2. Weight reduction rates are ranging from 35.6% to 64.5% and varying with the composition of food garbage. The less weight reduction rate is, the longer continuous-fermentation is. And the color of compost is changing sequentially as yellow -> brown -> black. 3. Comparing with the controlled microorganism group, the weight reduction rate and $H_2CO_3$ production rate in the characteristic microorganism group fermentation reactors are higher. And the fermentation rate is satisfactory when the characteristic microorganism group is added. 4. The value of fermented composting as fertilizer diminishes, and the contents of Total Nitrogen, $P_2O_5$, $K_2O$ increase on the condition that the fermentation continues. However, the organic contents and C/N ratio diminish as the fermentation continues. 5. The high-speed fermentation technology demonstractes the possibility of recycling as well as the reduction of composting time provided that it is applied as a pretreatment process for composting.

• Journal of the Korea Concrete Institute
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• v.14 no.2
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• pp.223-230
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• 2002

The main intent of this research was to determine the feasibility of utilizing recycling bottom ash as CLSM (controlled low-strength material). CLSM is a cementitious material, commonly a blend of portland cement, fly ash, sand, and water, that is usually flowable and self-leveling at the time of placement. The durability characteristics of mixtures made bottom ash we compared with those of fly ash CLSM in order to evaluate the effectiveness and suitability of bottom ash as material in CLSM. A comprehensive evaluation of the bottom ash in CLSM and mix proportions indicated that the bottom ash are capable of performing as CLSM mixtures. The durability characteristic of CLSM incorporating the bottom ash under various physical and chemical causes of deterioration were investigated. Test results indicated that CLSM using bottom ash has acceptable durability performance. CLSM incorporating with bottom ash were also found to be environmentally safe.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.91-96
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• 2011

The design, construction and management of underground facilities as infrastructure of nation should be properly carried out. One of reasons for underground facilitie's failure is a non-proper construction of backfill materials. This is common for circular underground pipes. A non-proper compaction is the cause of settlement and decrease of performance of underground facilities. The use of controlled low strength materials is an alternative to reduce the couple of failure problems. The flowability, self-cementation, and non-compaction are the major advantages to use the controlled low strength materials. In this research, couple of recycled materials, such as in-situ soil, water-treatment sludge, and crumb rubbers, were adopted. The basic properties of each materials were determined according to KS or ASTM. Also, couple of laboratory tests were carried out to get the design parameters for geotechnical and roadway area.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.688-696
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• 2014

A slew-rate control method of LCD driver ICs is introduced to increase uniformity between adjacent driver ICs and reduce power consumption. The slew rate of every voltage follower is calibrated by a feedback algorithm during the non-displaying period. Under normal operation mode, the slew rate is dynamically controlled for improving power efficiency. Experimental results show that the power consumption is reduced by 16% with a white pattern and by 10% with a black pattern, and display defects are successfully eliminated.

• BMB Reports
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• v.39 no.2
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• pp.132-139
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• 2006

Vascular endothelial cadherin (VE-cadherin), which belongs to the classical cadherin family, is localized at adherens junctions exclusively in vascular endothelial cells. Biochemical and biomechanical cues regulate the VE-cadherin adhesive potential by triggering the intracellular signals. VE-cadherin-mediated cell adhesion is required for cell survival and endothelial cell deadhesion is required for vascular development. It is therefore crucial to understand how VE-cadherin-based cell adhesion is controlled. This review summarizes the inter-endothelial cell adhesions and introduces our recent advance in Rap1-regulated VE-cadherin adhesion. A further analysis of the VE-cadherin recycling system will aid the understanding of cell adhesion/deadhesion mechanisms mediated by VE-cadherin in response to extracellular stimuli during development and angiogenesis.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.1-9
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• 1999

Effect of furnish on enzyme activity was investigated by using the three components (cellulose, enzyme, and cationic polyelectrolyte) model papermaking system. Avicel was used as a cellulose model compound to observe the effect of adsorption and desorption of enzyme with other component and the resultant change of particle size. As an experimental result, the enzyme loses considerably its apparent activity due to the adsorption onto cellulose and cationic polyelectrolyte. Activities of enzyme applied to the actual papermaking stocks having controlled fiber length showed different behavior in terms of pulp species UKP and KOCC stocks. That is, the enzyme activity in UKP was increased as fines content increased, however, vice versa in KOCC stock . This result can be considered to be the existence of various contaminants included in the fines of KOCC . The effect of possible contaminants such as inorganic materials, calcium ion, surfactant, and conductivity on enzyme activity were also investigated.