• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.78-83
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• 2000

The emission factor of nitrogen oxides(NOx) was evaluate to clarify the characteristics of NOx emitted from seven large combustion facilities in seoul area. The emission factors of NOx at A-1 and A-2 facilities of internal combustion engine were 66.957kgNOx/ton and 20.913kgNOx/ton, respectively. The emission factor of A-1 facility was higher than that of A-2 facility even same internal combustion engine, because A-1 facility adopted SCR(selective catalystic reactor) for reduction of NOx emission factor of A-2, A-4, and A-7 power generation boiler facilities were 4.300kgNOx/ton, 2.460kgNOx/ton and 1.796kgNOx/ton, respectively. The capacity of A-2 facility was about two times than that of A-4 and A-7. These emission factors were lower than those at facilities in other areas of korea, because of using low NOx burner of power generation boiler. The emission factors of NOx at A-3 and A-6 incinerator facilities were 0.147kgNOx/ton and 0.221kgNOx/ton which were lower than other facilities, respectively, because these facilities incinerate municipal solid waste of low heating value and uwe SCR for reducing NOx concentration.

• Journal of Urban Science
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• v.11 no.1
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• pp.29-35
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• 2022

Waste to Energy Plant were recognized as hateful facilities, and there were many conflicts in the location due to social problems such as the NIMBY phenomenon due to problems such as damage to property in the surrounding area, odor, and image loss. Problems such as air pollution and odor are solved by the development of advanced prevention facilities such as electric dust collectors, wet cleaning systems, semi-dry reaction towers, bag filters, and catalyst towers (SCR: Selective Catalytic Reduction), and air recycling facilities in waste storage tanks. However, it is being avoided because of the perception that it is an incinerator. To resolve these conflicts, the government installs and operates resident convenience facilities to compensate residents near resource recovery facilities, provides green space and improves the environment, and supports heating expenses in accordance with the 「Waste Treatment Facility Support Act」. The purpose of this study is to derive implications through the analysis of domestic and overseas case studies for resident convenience facilities and environment improvement for the promotion of local communities in resource recovery facilities and use them as basic data for community promotion and environmental improvement when installing resource recovery facilities in the future.

• Membrane Journal
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• v.32 no.2
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• pp.140-149
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• 2022

In this study, the conditions of low temperature and high pressure of biogas upgrading process using polysulfone membrane have been designed and tested to achieve the high recovery and efficiency corresponding to those of the highly selective polymeric materials. Polysulfone hollow fiber membrane with 4-component dope solution was spun via non-solvent induced phase separation. The hollow fiber membrane was mounted into a 1.5 inch housing. The effective area was 1.6 m², and its performance was examined in various operation temperatures and pressures. CO₂ and CH₄ permeances were 412 and 12.7 GPU at 20℃, and 280 and 3.6 GPU at -20℃, respectively, while the CO₂/CH₄ selectivity increased from 32.4 to 77.8. Single gas test was followed by the mixed gas experiments using single-stage and double stage where the membrane area ratio varied from 1:1 to 1:3. At the single-stage, CH₄ purity increased and the recovery decreased as the stage-cut increased. At the double stage, the area ratio of 1:3 showed the higher CH₄ recovery as decreasing the operation temperature at the same purity of CH₄ 97%. Finally, polysulfone hollow fiber membranes have yielded of both CH₄ purity and recovery of 97% at -20℃ and 16 barg.

• Journal of the Korean Institute of Rural Architecture
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• v.18 no.1
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• pp.19-28
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• 2016

This research aimed to suggest a standard design that reflects Hanok design tendency, and present a selective design that can fulfill a building owner's intention beyond the simple function of building permit or report. In addition, this research attempted to become a standard by establishing a criterion in calculating the measurements of section design or primary framework members, in order to be a guideline for designing Hanok in different sizes and forms. The results are as follows. The building area of Hanok standard design was set to be below $85m^2$, with a straight type of $83.16m^2$ and an L-shape of $84.24m^2$. By dividing the plane into a straight type and L-shape, two straight types were suggested: 'general type' and 'large living room type.' The upper floor space, along with the main room and small room, was proposed as an option to be changed into a room where an underfloor heating is installed depending on the building owner's intention. In addition, a criterion for side design and calculation of framework measurements was suggested and applied, while a five-girder design without high pillars was suggested for material-assembling structure. Two types of pillars-circumference and square cylinder-were proposed for the building owner to choose from, and a pointed beam house and ikgong(orthogonally-projected bracket) house were suggested for pojak bracket structure so either of them could be chosen according to the building owner's taste and economic condition. Finally, the sectional size of main materials were divided according to the form of pojak bracket structure to be proposed.

• Journal of the Korean Vacuum Society
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• v.12 no.3
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• pp.168-173
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• 2003

Recently, according to the rapid progress in Flat-panel-display industry, there has been a growing interest in the poly-Si process. Compared with a-Si, poly-Si offers significantly high carrier mobility, so it has many advantages to high response rate in Thin Film Transistors (TFT's). We have investigated a new process for the high temperature Solid Phase Crystallization (SPC) of a-Si films without any damages on glass substrates using thin film heater. because the thin film heater annealing method is a very rapid thermal process, it has very low thermal budget compared to the conventional furnace annealing. therefore it has some characteristics such as selective area crystallization, high temperature annealing using glass substrates. A 500 $\AA$-thick a-Si film was crystallized by the heat transferred from the resistively heated thin film heaters through $SiO_2$ intermediate layer. a 1000 $\AA$-thick $TiSi_2$ thin film confined to have 15 $\textrm{mm}^{-1}$ length and various line width from 200 to 400 $\mu\textrm{m}$ was used as the thin film heater. By this method, we successfully crystallized 500 $\AA$-thick a-Si thin films at a high temperature estimated above $850^{\circ}C$ in a few seconds without any thermal deformation of g1ass substrates. These surprising results were due to the very small thermal budget of the thin film heaters and rapid thermal behavior such as fast heating and cooling. Moreover, we investigated the time dependency of the SPC of a-Si films by observing the crystallization phenomena at every 20 seconds during annealing process. We suggests the individual managements of nucleation and grain growth steps of poly-Si in SPC of a-Si with the precise control of annealing temperature. In conclusion, we show the SPC of a-Si by the thin film heaters and many advantages of the thin film heater annealing over other processes