• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.1 s.119
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• pp.38-47
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• 2007

This study was carried out to develop a new application field and obtain the basic data of citrus peel as waste in Jeju island and traditional Hanji for producing functional Hanji. The results measuring physical and optical properties, water vapor permeance and antibacterial activity are as follows. It was revealed that apparent density go as down but bulk raise up in the structural view of Hanji with increasing of the addition various Korean citrus peel (citrus unshiu, cheonggyun and hanrabong peel, and citrus unshiu peel powder) percentages, and that the density of Hanji added citrus unshiu peel was higher, but bulk was lower in compared with Hanji added other kinds of peel. Those Hanji added citrus unshiu peel, cheonggyun peel, hanrabong peel and citrus unshiu powder were very great not only in the strength (breaking length, burst index, tear index and folding endurance) but also in water vapor permeant rate in comparison with Hanji. The pHs of Hanji were neutrality (7 to 8). The brightness of the Hanji added various citrus peel percentages was low in compared to Hanji, and the 40% addition of hanrabong peel was the lowest. When 40% hanrabong peel was added to Hanji, it was very yellow in the color degree. When cheonggyun peel was added to Hanji manufacture, water vapor permeant rate was highly effective. It is known that vacant space of intrafiber was reduced by image analysis of Hanji and the additions of peel of citrus unshiu, cheonggyun and hanrabong were distributed equally in the interior of Hanji. The antibacterial activity of Hanji added citrus unshiu peel is more than 98%. After all, it would be able to increase utilization of Hanji, extensively. Namely, production of high quality Hanji added functional materials is expected for new valuable industry of citrus peel and Hanji.

• Journal of the Korean Vacuum Society
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• v.20 no.3
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• pp.217-224
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• 2011

of materials and simplification of process. Micro-blasting is one of the promising method for recycling of waste wafer due to their simple and low cost process. Therefore, in this paper, we make recycling wafer through the micro-blaster. A surface etched by micro-blaster forms particles, cracks and pyramid structure. A pyramid structure formed by micro-blaster has a advantage of reflectivity decrease. However, lifetime of minority carrier is decreased by particles and cracks. In order to solve this problems, we carried out the DRE(Damage Romove Etching). There are two ways to DRE process ; wet etching, dry etching. After the DRE process, we measured reflectivity and lifetime of minority carrier. Through these results, we confirmed that a wafer recycled can be used in solar cell.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.4
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• pp.235-246
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• 2002

The fish farming using net cages has been developed in many semi-closed bays in the southern coast of Korea for the last two decades. The intensive cage cultures of fishes generate considerable amounts of organic waste in the form of uneaten food and faeces. In order to evaluate the effect of fish farming activities we collected the benthic macrofauna near the fish farm area located in Wolho Islet of Gamak Bay and in Haklim Island of Tongyeong in November 1998. Benthic macrofaunal assemblages showed dramatic changes in species number, species diversity, and faunal abundance in the region of the fish farm. These changes were clearly observed even at a distance of up to 30 m from the fish farming cage area. Within 5 m from the cage, there was a zone with low species diversity and highest density, dominated by opportunistic polychaete worm, Capitella capitata. By a distance of 15-30 m, this zone presents highest species number and higher density. Our results clearly demonstrated that fish farm area was highly enriched with organic materials, and implied that the fish farm industry and adjacent benthic ecosystem in semi-closed bay will be seriously damaged by self produced organic wastes in the near future.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.194-199
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• 2005

The principle of vortex cyclone was applied to enhance the treatment efficiency of waste air streams containing particulate matters, phenol, and others. Adsorption, condensation, and/or coagulation could be induced at low temperature zone formed by Joule-Thomson expansion as the pressurized air and pulverized activated carbon were introduced at the tangential direction into the cyclone system applied with the coaxial funnel tube of vortex cyclone. Easily condensible vapors were adsorbed and/or condensed forcibly on coagulated or condensed materials which were formed as cores for coagulation or condensation by themselves or on pulverized activated carbons. These types of coagulation or condensation rates were rapidly promoted by increase in their diameter. The maximum removal efficiency obtained from this experiment for the removal of carbon dioxide and phenol was about 87.3 and 93.8 percent, respectively. Phenol removal efficiency was increased with the relative humidities and enhanced by pulverized activated carbon added. The Joule-Thomson coefficients were increased with the pressure of air injected in the range of the relative humidities between 10% and 50%. It is believed that the moisture, particulate matters, and the pressure of the process air introduced could control the removal efficiency of VOCs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.314-321
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• 2016

After the 1980s, as the economy was growing rapidly and the real estate market was active, a large increase in population was supplied to the city. Accordingly, the national apartment housing market is located in the form of Urban Housing Culture. On the other hand, with time, the supply apartment houses became superannuated and the residential environment became poor. Therefore, the environment of old apartment houses has been changed to improve by reconstruction. Despite this, reconstruction incurred not only a lot of construction waste, but also problems of environmental degradation, noise, traffic congestion, increasing number of households, and so on. Recently, the housing law has changed, and vertical extension remodeling focused on Small/Medium Town House is underway. This has been changed in response to the demand. This is one of essential parts in the remodeling field for the future, even though it has some problems in how uses existing buildings. Therefore, this study analyzed occurrence risk factor for each type through research materials and case analysis regarding the vertical extension remodeling of apartment housing. In addition, the relative importance was determined through questionnaires and interviews from constructors, designers, and experts in the field.

• Resources Recycling
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• v.25 no.6
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• pp.13-22
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• 2016

This study is aimed at compare and evaluate the environmental impact of End-of-Life Vehicle(ELV) on the eco-friendly technology dismantling and recycling system, using Life Cycle Assessment (LCA) method. In this study, it was analyzed for the environmental impacts of raw materials, disassemble process, recycle parts separation and waste treatment into the process of ELV treatment by greenhouse gas and resource consumption, etc. Through this study, the indoor rail type dismantling technology were recycling rate applied on the alternate system was increased by approximately 8%. As a result, it was 3 to 88% by improving the environmental impact category. In addition, the added benefit of approximately 8 - 62% in pre-market occurred through the recycling rate, improve parts reuse rate of ELV. Through the results of this study, legal compliance, improved reuse and recycling ratio, used parts market reach, enable exports has identified the need for the effort that the dissemination and diffusion of eco-friendly technology.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.897-902
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• 2006

This study was carried out to investigate the possibility for utilization of waste materials and the characteristics of pork by feeding citrus byproducts. The groups consisted of the pork without citrus byproduct (TB-0) and the pork fed with 6% and 10% citrus byproduct during growing and fattening period (TB-1). The contents of moisture, crude protein, crude fat, crude ash, vitamin $B_1$ and $B_2$, total amino acids, and caloric were not significantly different between TB-0 and TB-1 (p>0.05). The contents of cholesterol and the magnesium of TB-1 were lower than those of TB-0. Palmitic acid was the most abundant among saturated fatty acids while oleic acid was the most abundant among unsaturated fatty acids in both groups. In case of sensory score, the color and aroma of raw meat and taste, texture, juiciness and palatability of boiled meat were not influenced by feeding of citrus byproduct. But the flavor preference of boiled meat of TB-1 was higher than that of TB-0.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.46-50
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• 1998

This study was conducted with pot experiment to find out the effect of ginkgo leaf wastes application produced from the pharmaceutical process on the growth and yield of red pepper. Four kinds of ginkgo leaf wastes, the natural dried leaves, the leaves produced from the pharmaceutical process, the dried leaves to remove methanol after the pharmaceutical process, and the leaves washed with water to removal methanol and some activated materials after pharmaceutical process, were treated with two levels of application rates. The growth responses and yield were measured throughout the experimented period. Shoot growth of red pepper was inhibited by all treatment of ginkgo leaf wastes compared to the treatment of NPK and NPK+compost. Red pepper yields were also significantly reduced by treatment of the ginkgo leaf wastes except for the treatment of the water washed ginkgo leaf wastes, 1,000 kg/10a, which showed similar yield to NPK treatment. The major reseon to reduce the growth and yield seemed to be originated from the allelopathic substances of the ginkgo leaves. The organic matter contents of the soil after experiment were slightly increased with the treatment of the ginkgo leaf wastes and compost than that of NPK treatment. Based on these results, this study for using the ginkgo leaf wastes should be done more to utilize the wastes of the pharmaceutical process as a organic fertilizer.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.599-615
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• 2022

In order to excavate underground tunnel most safely such as Han river, the slurry shield TBM method is applied to cope with face of high water pressure for many metro projects. In downtown subway project most of excavated soil is discharged externally whereas in road construction excavated soil is used as filling materials so it becomes important factor for success of the project. After excavated soil, weathered rock and soft rock are discharged with bentonite through discharge pipe to slurry treatment plant then those soils are separated in separation plant according to those size. Fine grained soil has been discarded together with filter cake but it is not toxic and can be mixed with coarse aggregate in proper ratio so this study is performed to find use of qualified filling material to meet quality standard. Therefore, in this study, legal standards and quality standards for the utilization of excavated soil of the slurry shield TBM method were examined and test was conducted to derive recycling way for filter cake and aggregate. And a plan for using it as a filling material for road construction was derived. Because bentonite is a clay composed of montmorillonite, and the excavated soil in the tunnel is also non-toxic, disposal of this material can waste social cost so it is expected to be helpful in the underground space development project that carries out the TBM project by recycling it as a valuable resource.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.295-302
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• 2021

Surface modification of recycled plastic film-based aggregates is demonstrated to enhance the interaction between aggregates and cement paste. It is shown that the oxygen(O₂) atmospheric pressure plasma(APP) treatment leads to a drastic increase in hydrophilicity. In case of the plasma treatment at 100W of RF power, 15/4sccm of O₂/Ar flow rate and 30sec of discharging time, the water contact angle on the aggregates surface decreased from 104.5° to 44.0°. In addition, the contact angle of surface modified aggregates kept in air increased with time elapse. Improvement of hydrophilicity can be explained by the formation of new hydrophilic oxygen functional groups which is identified as C-OH, C-O-C, C=O, -COOH by X-ray photoelectron spectroscopy(XPS) analysis and Fourier-transform infrared spectroscopy(FT-IR). Therefore, it can be concluded that the plasma treatment process is an effective method to improve adhesion of the recycled plastic film-based aggregates and cement paste.