• Title/Summary/Keyword: Co-conversion

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H.264 Deblocking Filter Implementation Method Considering $8\times8$ Block-Based Post-Filtering ($8\times8$ 블록기반의 후처리필터링을 고려한 H.264 블록화 현상 제거부 설계 기법)

  • Kim Sung Deuk;Cho Hong Kyu
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.2 s.302
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    • pp.19-26
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    • 2005
  • After various video coding standards such as H.263, MPEG-4, and H.264 have been introduced, there has bun strong need to support the multiple standards with limited resources efficiently. In terms of deblocking Inter which plays an important role in improving visual quality, K264 deblocking filter implementation has different aspects as compared with traditional $8\times8$ block-based post-filter implementation. Analyzing the differences, this paper proposes a H.264 deblocking filter implementation method that supports $8\times8$ block-based post-filtering for the traditional video coding systems. In the proposed implementation method the block boundaries to he filtered are adaptively chosen for $8\times8$ and $4\times4$ block boundary filtering. Since the filtered result is selectively used for motion compensation or not, both loop-filtering and post-filtering can be achieved. A quantization parameter conversion unit that converts H.263 quantization parameters to H.264 quantization parameters is utilized by examining the $8\times8$ block boundary errors based on human visual system. Since the original nature of the H.264 deblocking filter is well expanded to the $8\times8$ block-based post-filter with minor modifications, the proposed implementation method is suitable to implement the deblocking function of the multiple video standards such as H.263, MPEG-4, and K264, efficiently.

A Study on Characteristics of HI Decomposition Using Pt Catalysts on ZrO2-SiO2 Mixed Oxide (ZrO2-SiO2 복합산화물에 담지된 백금 촉매의 요오드화수소 분해 특성 연구)

  • Ko, Yunki;Park, Eunjung;Bae, Kikwang;Park, Chusik;Kang, Kyoungsoo;Cho, Wonchul;Jeong, Seonguk;Kim, Changhee;Kim, Young Ho
    • Journal of Hydrogen and New Energy
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    • v.24 no.5
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    • pp.359-366
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    • 2013
  • This work is investigated for the catalytic decomposition of hydrogen iodide (HI). Platinum was used as active material by loading on $ZrO_2-SiO_2$ mixed oxide in HI decomposition reaction. To obtain high and stable conversion of hydrogen iodide in severe condition, it was required to improve catalytic activity. For this reason, a method increasing dispersion of platinum was proposed in this study. In order to get high dispersion of platinum, zirconia was incorporated in silica by sol-gel synthesis. Incorporating zirconia influence increasing platinum dispersion and BET surface area as well as decreasing deactivation of catalysts. It should be able to stably product hydrogen for a long time because of inhibitive deactivation. HI decomposition reaction was carried out under the condition of $450^{\circ}C$ and 1 atm in a fixed bed reactor. Catalysts analysis methods such as $N_2$ adsorption/desorption analysis, X-ray diffraction, X-ray fluorescence, ICP-AES and CO gas chemisorption were used to measurement of their physico-chemical properties.

Performance and Carcass Composition of Growing-finishing Pigs Fed Wheat or Corn-based Diets

  • Han, Yung-Keun;Soita, H.W.;Thacker, P.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.5
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    • pp.704-710
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    • 2005
  • The objective of this experiment was to compare corn and wheat in finishing pig diets in order to determine whether performance, carcass quality, fatty acid composition or fat colour is altered by choice of cereal grain. A total of 126 crossbred pigs were used in this experiment. At the start of the experiment, a portion of the experimental animals were assigned to receive a wheat-based diet formulated using soybean meal as the sole source of supplementary protein. The remainder of the pigs were assigned to a corn-based diet formulated to supply a similar level of lysine (0.65%) and energy (3,300 kcal/kg DE). At two week intervals, a portion of the pigs on the corn-based diet were switched to the wheat-based diet so that a gradient was produced with pigs being fed the corn and wheatbased diets for different proportions of the finishing period ranging from 100% on wheat to 100% on corn. There were no significant differences in the growth rate of pigs fed the two diets (p = 0.834). Pigs fed wheat tended to consume slightly less feed (p = 0.116) and had a significantly improved feed conversion (p = 0.048) compared with pigs fed corn. Choice of cereal did not affect dressing percentage (p = 0.691), carcass value index (p = 0.146), lean yield (p = 0.134), loin fat (p = 0.127) or loin lean (p = 0.217). Fatty acid composition of backfat was unaffected by the cereal grain fed (p>0.05). Total saturated fatty acid content was 33.31% for both corn and wheat fed pigs (p = 0.997) while the polyunsaturated fatty acid content was 12.01% for corn fed pigs and 11.21% for wheat fed pigs (p = 0.257). The polyunsaturated/saturated ratio was 0.36 for pigs fed corn and 0.34 for pigs fed wheat (p = 0.751). Hunter Lab Colour Scores indicated no difference either in the whiteness or yellowness of the fat. In conclusion, wheat can substitute for corn in growingfinishing pig rations without detrimental effects on pig performance. There were no differences in either the fatty acid composition of backfat or in backfat colour indicating that the decision to use wheat vs. corn needs to be made on economic grounds rather than being based on their effects on fat quality.

A study of NOx performance for Cu-chabazite SCR catalysts by Sulfur poisoning and desulfation (Cu-Chabazite SCR Catalysts의 황 피독 및 탈황에 의한 NOx 저감 성능에 관한 연구)

  • Nam, Jeong-Gil
    • Journal of Advanced Marine Engineering and Technology
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    • v.37 no.8
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    • pp.855-861
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    • 2013
  • Small-pore Cu-chabazite SCR catalysts with high NOx conversion at low temperatures are of interest for marine diesel engines with exhaust temperatures in the range of 150 to $300^{\circ}C$. Unfortunately, fuels for marine diesel engines can contain a high level of sulfur of up to 1.5% by volume, which corresponds to a $SO_2$ level of 500 ppm in the exhaust gases for an engine operating with an A/F ratio of 50:1. This high level of $SO_2$ in the exhaust may have detrimental effects on the NOx performance of the Cu-chabazite SCR catalysts. In the present study, a bench-flow reactor is used to investigate the effects of sulfur poisoning on the NOx performance of Cu-chabazite SCR catalysts. The SCR catalysts were exposed to simulated diesel exhaust gas stream consisted of 500 ppm $SO_2$, 5% $CO_2$, 14% $O_2$, 5% $H_2O$ with $N_2$ as the balance gas at 150, 200, 250 and $300^{\circ}C$ for 2 hours at a GHSV of 30,000 $h^{-1}$. After sulfur poisoning the low-temperature NOx performance of the SCR catalyst is evaluated over a temperature range of 150-$300^{\circ}C$ to determine the extent of the catalyst deactivation. Desulfation is also carried out at 600 and $700^{\circ}C$ for 30 minutes to determine whether it is possible to recover the NOx performance of the sulfur-poisoned SCR Catalysts.

Emulsion Polymerization of Vinyl acetate-Butyl acrylate Copolymer (유화 중합에 의한 비닐 아세테이트-부틸 아크릴레이트 공중합체의 합성 연구)

  • 설수덕;임종민
    • Polymer(Korea)
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    • v.28 no.2
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    • pp.135-142
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    • 2004
  • Poly(vinyl acetate) (PVAc) prepared by emulsion polymerization has broad applications for additives such as paint binder, adhesive for wood and paper due to its low glass transition temperature which help to plasticize substrate resins. Since emulsion polymerization has a disadvantage that surfactant and ionic initiator degrade properties of the product polymer, poly(vinyl acetate-co-butyl acrylate) (VVc-BA) was synthesized using potassium persulfate as catalyst and poly(vinyl alcohol) (PVA) as protective colloid to prevent the degradation. The copolymer latex product was internally plasticized and has enhanced colloid stability, adhesion, tensile strength and elongation. During VAc-BA emulsion polymerization, no coagulation and complete conversion occur with the reactant mixture of 0.7wt% potassium persulfate, 15wt% poly(vinyl alcohol) (PVA-217), and the balanced monomer that the weight ratio of vinyl acetate to butyl acrylate is 19. As the concentrations of PVA increase, the copolymerization becomes faster and polymer particles are more stable, resulting in enhanced mechanical stability of the VAc-BA copolymer. However, the size of the polymer particles decreases with increasing PVA contents. Properties of the VAc-BA copolymer, such as minimum film formation temperature, glass transition temperature, surface morphology, molecular weight and molecular weight distribution, tensile strength and elongation, were characterized using differential scanning calorimeter, transmission electron microscope and other instruments.

A Study on the Effect of Different Functional Groups in Anion Exchange Membranes for Vanadium Redox Flow Batteries (바나듐 산화환원 흐름전지를 위한 음이온교환막의 관능기에 따른 특성 연구)

  • Lee, Jae-Myeong;Lee, Mi-Soon;Nahm, Ki-Seok;Jeon, Jae-Deok;Yoon, Young-Gi;Choi, Young-Woo
    • Membrane Journal
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    • v.27 no.5
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    • pp.415-424
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    • 2017
  • Commonly cation exchange membranes have been used for vanadium redox flow batteries. However, a severe vanadium ion cross-over causes low energy efficiency. Thus in this study, we prepared 3 different anion exchange membranes to investigate the effect on the membrane properties such as vanadium ion cross-over and long term stability. The base membranes were prepared by an electrolyte pore filling technique using vinyl benzyl chloride (VBC), divinylbenzene (DVB) within a porous polyethylene (PE) substrate. Then 3 different functional amines were introduced into the base membranes, respectively. These resulting membranes were evaluated by physico-chemical properties such as ion exchange capacity, dimensional stability, vanadium ion cross-over and membrane area resistance. Conclusively, TEA-functionalized membrane showed longest term stability than other membranes although all the membranes are similar to coulombic efficiency.

A Comparative Study of Commercial Catalysts for Methanol Steam Reforming (메탄올 수증기 개질반응에서의 상용촉매 비교연구)

  • Park, Jung-Eun;Park, Jae-Hyun;Yim, Sung-Dae;Kim, Chang-Soo;Park, Eun-Duck
    • Korean Chemical Engineering Research
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    • v.49 no.1
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    • pp.21-27
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    • 2011
  • The comparison work was conducted for the methanol steam reforming among commercial Cu-based catalysts, viz. ICI-M45, which is for the methanol synthesis, MDC-3 and MDC-7, which are for the water-gas shift reaction. The catalytic activity for the water-gas shift reaction was also compared over three catalysts. Among them, MDC-7 showed the highest methanol conversion and formation rate of hydrogen and carbon dioxide at 473 K for the methanol steam reforming. To find out any promotional effect between ICI-M45 and MDC-7, three different packing methods with these two catalysts were examined. However, no synergistic effect was observed. The catalytic activity for watergas shift reaction decreased in the following order: MDC-7 > MDC-3 > ICI-M45. The highest activity of MDC-7 for the methanol steam reforming as well as the water-gas shift reaction can be due to its high surface area, copper dispersion, and an adequate Cu/Zn ratio.

Removal of tar and particulate from gasification process using pre-coating technology (바이오매스 가스화 공정의 생성가스 중 타르 및 입자 제거를 위한 pre-coating 기술 연구)

  • Kim, Joon-Yub;Choi, Byoung-Kwon;Jo, Young-Min;Kim, Sang-Bum
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.12
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    • pp.804-815
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    • 2019
  • Due to the depletion and environmental problems of fossil fuel, biomass has arisen as an alternative energy source. Biomass is a renewable and carbon-neutral source. However, it is moister and has lower energy density. Therefore, biomass needs thermal chemical conversion processes like gasification, and it does not only produce a flammable gas, called 'syngas', which consists of CO, H2, and CH4, but also some unwanted byproducts such as tars and some particulates. These contaminants are condensed and foul in pipelines, combustion chamber and turbine, causing a deterioration in efficiency. Thus this work attempted to find a method to remove tars and particles from syngas with a filter which adopts a pre-coating technology for preventing blockage of the filter medium. Hydrated limestone powder and activated carbon(wood char) powder were used as the pre-coat materials. The removal efficiency of the tars was 86 % and 80 % with activated carbon(wood char) coating and hydrated limestone coating, respectively.

Comparative Study of the Effects of the Intermodal Freight Transport Policies (인터모달 추진 정책과 효과에 관한 비교연구)

  • Woo, Jung-Wouk
    • Journal of Distribution Science
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    • v.13 no.10
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    • pp.123-133
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    • 2015
  • Purpose - The Korean government has devised intermodal transportation policies and granted subsidies to shippers and logistics companies that made a conversion of transportation means through the policies. This provides support by expanding the complex uniform railroad transportation and overhauling the deteriorated railroad facilities. As for 2013, however, the freight transportation percentage of railroad was 4.5% in tons and 8.5% in ton kilometers. Meanwhile, since the 1990s, developed countries such as the U.S. and Europe have been trying to expand intermodal freight transport with a legal and institutional support to build a logistics system corresponding with social and economic environmental changes. In this study, I set out to examine the effects of the intermodal freight transport policies in the EU and the U.S., and to explore the direction of setting up a rail intermodal transport system in South Korea. Research design, data, and methodology - The paper used a qualitative research methodology through the literature review. First, was an overview of Intermodal transportation in the EU, U.S. and UN. Second, it describes the development of transport in Europe and the U.S. with particular emphasis on intermodal freight transport. Third, it explores the direction of setting up a intermodal freight transport in South Korea. The last section contains concluding remarks. Results - As for the EU, it has been promoting integration between transport and intermodal logistics network designs while utilizing ITS or ICT and supports for rail freight intermodal by giving reduction to a facilities fee or subsidizing for rail freight in order to minimize the cost of external due to freight transport. On the other hand, as for the U.S., it has been made up of an industrial-led operating project and has been promoting it to improve accessibility between intermodal hubs and cargo terminals through intermodal corridor program, and an intermodal cargo hub access corridor projects, etc. Moreover, it has tried to construct intermodal transport system using ITS or ICT and to remove Barrier. As a result, in these countries, the proportion of intermodal freight transport is going to be the second significant transport compared with rail and maritime transport. An Effective rail intermodal transport system is needed in South Korea, as seen in the case of these countries. In order to achieve this object, the following points are required to establish radical infrastructure policy; diversify investment financing measures taken under public-private partnerships, legal responsibilities, improvement of utilization of existing facilities to connect the railway terminal and truck terminal, and enhancement service competitiveness through providing cargo tracking and security information that combines the ITS and ICT. Conclusions - This study will be used as a basis for policy and support for intermodal freight transport in South Korea. In the future, it is also necessary to examine from the perspective of the shipper companies using the rail intermodal transport, ie, recognition of shipper, needed institutional supports, and transportation demand forecasting and cost-effective analysis of the railway infrastructure systems improvement.

Effect of Dietary β-Mannanase Supplementation and Palm Kernel Meal Inclusion on Laying Performance and Egg Quality in 73 Weeks Old Hens

  • Lee, Jun Yeob;Kim, Sang Yun;Lee, Jae Hwan;Lee, Jeong Heon;Ohh, Sang Jip
    • Journal of Animal Science and Technology
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    • v.55 no.2
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    • pp.115-122
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    • 2013
  • This study was conducted to evaluate the effect of dietary ${\beta}$-mannanase supplementation and palm kernel meal (PKM) inclusion (5%) on laying performance, egg quality and nutrient utilizability of laying hens with 73 weeks of age. A total of 240 Lohmann brown laying hens with average 77.5% egg production were randomly allocated with 60 hens per treatment, 4 replicates per treatment and 15 hens per replicate. Experimental design was a completely randomized design with $2{\times}2$ factorial arrangement, with the factors being (1) two levels of PKM (0 vs. 5%) and (2) with or without dietary ${\beta}$-mannanase (480 IU/kg of diet CTCzyme$^{(R)}$) supplementation. All hens were housed in cages ($35cmW{\times}35cmD{\times}40cmH$) with 2 hens per cage for six weeks feeding trial. Laying performance was recorded daily during feeding trial. Egg quality, nutrients utilizability and blood assays were done at the end of feeding trial. Egg production was improved (P<0.05) by both dietary PKM inclusion and ${\beta}$-mannanase combined supplementation. Either ${\beta}$-mannanase or PKM did not affect feed intakes and feed conversion ratio of all diets. Egg weight of hens fed diet containing 5% of PKM had heavier (P<0.05) eggs compared with hens fed without PKM. Albumen height was improved (P<0.05) by dietary mannanase supplementation. Crude fat utilization of 5% PKM diet was higher than that of no PKM diet regardless of ${\beta}$-mannanase supplementation. Both DM and total carbohydrate utilization were decreased (P<0.05) in hens fed 5% PKM diet. Serum IgG and yolk IgY contents of PKM groups were lower (P<0.05) than those of no PKM groups. This result showed that 5% PKM diet, independent of dietary ${\beta}$-mannanase supplementation, was able to improve egg production. In addition, dietary ${\beta}$-mannanase supplementation could be used for improving the albumen height of eggs.