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        21.
        2013.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : The objective of this study is to evaluate the applicability of the pitch, which is produced during SDA petroleum upgrading process, as a pavement paving material. In order for the purpose, the physical and chemical properties of the pitch are analyzed, and then the various plasticizers are applied in the pitch. METHODS: Two types of pitch are selected from oil refinery companies, which are owned the SDA petroleum upgrading process. Also, two types of asphalt binders, PG 64-22 and PG 58-22, are employed to compare with the pitch because these two types of asphalt binders are currently used as paving materials. For the chemical property of the pitch, the composition of SARA (Saturate, Aromatic, Resin, Asphaltene), the elementary composition, and the functional group are analyzed. For the physical property of the pitch, the basic material property tests, such as penetration test, softening point test, flash point test, ductility test, and rotational viscometer test, are performed. Also, the DSR (Dynamic Shear Rheometer) test and the BBR (Bending Beam Rheometer) test are conducted using asphalt binder specimens obtained by both short term aging (Rolling Thin Film Oven, RTFO) and long term aging (Pressure Aging Vessel, PAV) processes. The rheological property of each pitch type is evaluated as a function of temperatures and loading cycles. PG 64-22 asphalt binder is used as a control material. RESULTS AND CONCLUSIONS: The Pitch may not be suitable for the pavement paving material without modifications, but the pitch can be used as alternatives of modified addictive or asphalt. If low molecular component, such as saturate and aromatic components, are added in the pitch based on the development of various plasticizers, it has a strong possibility for the pitch to be used as a alternative. However, in order to verify the performance property of the pitch, further research is needed.
        4,000원
        22.
        2007.02 구독 인증기관 무료, 개인회원 유료
        This study presented the plan for treatment plant as investigating the technical examination of existing landfill leachate treatment plant at Geumgo-Dong and the plan of landfill leachate treatment with sewage treatment. The R/O process in 1st stage landfill leachate treatment plant(plant capacity:150m3/d) was closed in consideration of economical aspect and efficiency. It is to be desired that the 1st stage and 2nd stage landfill leachate treatment (plant capacity: 250m3/d) are combined, and are converted the Pretreatment process with nitrogen treatment process, and after total landfill treatment leachate happened from landfill site is pretreated it is transferred the sewage treatment plant. Ammonia nitrogen load of landfill leachate that was transferredthe sewage treatment plant(plant capacity: 300,000m3/d). This load is no problem at now, but it is need change the inflow line for sewage treatment plant and the enlargement of pretreatment process in case that the raw landfill leachate is increased.
        5,400원
        23.
        1994.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this paper, the unit processes in the typical water treatment plant, which need to be expanded because the water demand is over the existing water treatment capacity in the near future, were carefully examined to upgrade the water treatment plant. The models were installed in the fields as a distorted model based upon the hydraulic similitudes. The models having the constant discharge ratio in the unit processes between the model and the prototype were installed as two units to compare the treatment efficiencies. The capacity of the individual unit, which is a model of the prototype of $250,000m^3/day$ capacity, was $24m^3/day$. In the mixing and flocculation experiments, the mixing intensity of flocculators G was selected as the main experimental item. The optimal mixing intensities G, which are 65/sec for experimental discharge of $1m^3/hr$ and 85/sec for experimental discharge of $1.3m^3/hr$, are identified based upon the comparison the relative turbidity removal efficiencies. Also, the outlet weir loading was selected as the main experimental item in the sedimentation process. Through the continuous experiments with the main experimental items of the mixing intensity of flocculators G and the outlet loading of the weir in the sedimentation basin, about 20% upgrading compared to the existing water treatment capacity was obtained.
        4,000원
        24.
        2019.02 KCI 등재 서비스 종료(열람 제한)
        Purpose - The industrial structure upgrading can play an important role in promoting the carbon emission efficiency. Thus, this paper attempts to study the impact of industrial structure upgrading on carbon emission efficiency in order to reduce carbon emissions. Research design, data, and methodology - This paper selects panel data of 30 provinces and municipalities (autonomous regions) in China from 2001 to 2016, and divides them into three regions. The Moore index is used to measure the industrial structure upgrading, the non-radial SBM model based on undesired output is used to measure the slack variable to calculate the total factor carbon emission efficiency. Finally the impact of industrial structure upgrading on the carbon emission efficiency are analyzed. Results - It is found that the Moore index and the carbon emission efficiency in the eastern region is the highest in the three regions. Conclusions - The influence of various influencing factors on carbon emission efficiency is different between regions. The Moore index has a positive effect on the carbon emission efficiency in the eastern region, and has a negative influence coefficient on the central region. The effect on the western region is not obvious.
        25.
        2018.09 KCI 등재 서비스 종료(열람 제한)
        In the case of solid refuse fuel manufacturing facilities, residues, which are left-over from the process, are buried at a rate of 34% of incoming amount, and some are disposed of by combustion. The residues were upgraded by mechanical biological treatment and subject to attempts at combustion, and the bottom ash generated from combustion tests was applied to fabricate bricks for recycling. The brick was manufactured by substitutions of stone powder, cement, sand ranging from by 3 to 30% according to experimental conditions. These could be used as an interlocking block for the sidewalk or open spaces. The basic characteristics of the bottom ash and the water absorption, bending strength, compressive strength, and dimensions of the mixed bricks were tested. Results showed that 10% of the stone powder substitution was regarded as an optimal condition, and the brick quality was satisfactory under given standards, because the pozzolanic and hydration reactions occurred effectively.
        26.
        2018.05 KCI 등재 서비스 종료(열람 제한)
        Purpose - The development of Anhui high-tech industry is the key to transforming the mode of economic development and optimizing the industrial structure. Research design, data, and methodology - The data of paper that is the data of Anhui province and the six provinces of central China from 2010 to 2015, which analyzed the present situation of High-tech industry in Anhui Province by means of data comparison and literature analysis, and then explored several possible modes of undertaking. Results - With the analysis of the current situation of the development of high-tech industry in Anhui Province, several possible modes for undertaking the transfer of high-tech industries in Anhui Province were explored: The mode of undertaking of Leading Enterprises + Industrial park, the mode of undertaking of differentiated development + Regional comprehensive exploitation and the mode of undertaking "Dynamic industrial Chain" + industrial cluster. Conclusions - Based on the perspective of industrial upgrading, this paper analyzes the shortcomings of Anhui Province in the traditional mode of undertaking industrial transfer and expounds the inherent requirements of innovation industry undertaking. Finally, on the basis of the above analysis, the author explored three possible modes of acceptance.
        27.
        2018.05 서비스 종료(열람 제한)
        바이오가스의 고질화 공정에서는 필수적으로 메탄의 손실이 발생하게 된다. 특히 기체분리막을 이용한 바이오가 고질화는 타 공정에 비해 경제적이라는 장점이 있지만 메탄 손실율이 높은 편이다. 메탄 손실율이 줄이기 위해서는 고선택도의 분리막 모듈이 요구된다. 분리막을 이용한 바이오가스 고질화 공정에서 메탄손실율이 높은 이유는 CO2에 의한 가소화(Plasticization)으로 CH4의 투과도가 증가하기 때문이다. Cellulose계열의 고분자는 CO2 가소화에 대한 영향이 적기 때문에 CA(Cellulose Acetate)를 사용하여 고선택도의 분리막 개발이 가능하다. 따라서, 투과도가 높은 막을 개발하기 위해 도프용액의 농도와 에어갭(Evaporation time)을 변화시키면서, CA의 두께와 기공을 조절하여, 고선택도의 CA 분리막을 제막하였다. 비용매 유도상 분리법(NIPS, nonsolvent induced phase separation)을 이용하여 제막하였다. 실험에 사용된 Eastman사의 CA를 더 이상 정제하지 않고 그대로 사용하였으며, 도프용액은 다성계로 중합체(polymer), 용매(solvent), 비용제(nonsolvent)를 혼합하여 분리막을 방사하였다. CA의 함량이 증가할수록 active layer 층이 두꺼워지므로 분리막의 선택도가 증가하는 경향을 보였다. 하지만, CA함량이 증가할수록 support layer의 다공층이 줄어들게 되고 active layer층이 두꺼워지므로 투과도도 함께 줄어들게 된다. CA 21wt%에서의 메탄의 투과도와 선택도는 1.3 GPU 및 33.0이였으며, CA 25wt%에서의 메탄 투과도와 선택도는 0.1 GPU 및 43.6으로 고선택도 분리막을 제막하였다.
        28.
        2016.07 KCI 등재 서비스 종료(열람 제한)
        High-rank coals are limited, while low-rank coals are abundant. However, the low-rank coals needs upgradation so as to improve their quality. If not, the utilization of low-rank coals will lead to many operational difficulties. As this study was made in South Korea, this article discusses the energy and coal scenario of South Korea. The critique discusses the concerns of utilizing low-grade coal and the need for upgrading low-grade coal. The article also briefly discusses the currently practiced low-rank coal upgradation techniques. Also, the review paper suggests some best upgradation techniques.
        29.
        2014.06 KCI 등재 서비스 종료(열람 제한)
        In this research, the upgrading technology and policy trends for biogas were examined with a focus on the European Union (EU). Depending on the capacity of the biogas upgrading facility investment costs are different. In addition, biogas upgrading technology-specific energy demand is lowest in the amine scrubber process. Organic waste met the sustainability criteria. Also, the energy content was four times larger, and the results showed that the utilization value was significant. Through cogeneration, and it can secure various markets. Because of these advantages, various policies are being promoted in the EU. In the future, South Korea needs to model its biogas policy after the upgrading technology and policy trends in the EU, and it should strive to create a market for biomethane.
        30.
        2011.02 서비스 종료(열람 제한)
        최근 세계 곳곳에서 대규모 지진이 발생하여 건축물 붕괴에 따른 피해가 속출함에 따라 지진에 대비하기 위해 기존 건축물의 내진 성능을 보강방안에 대한 관심이 높아지고 있다. 그러나 현재 우리나라의 경우, 교육생활의 터전임과 동시에 가구 재난 발생 시 지역주민들의 응급피난장소인 학교 건축물조차 내진설계가 제대로 이루어져 있지 않고 있어, 지진 발생 시 막대한 피해가 예상된다. 현 상황을 극복하기 위해 기존 노후화 학교 건축물의 내진성능을 향상시키기 위한 적절한 보강방안이 제시되어야한다. 본 논문에서는 범용해석프로그램을 통해 기존 노후화 학교 건축물에 대한 비선형정적해석에 결과에 따른 내진보강 후 비선형 시간이력해석을 실시하여 지진하중에 의한 구조물의 비선형 거동을 규명하고 내진 보강 효과를 검증하고자 한다.
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