• 제목/요약/키워드: Active regeneration

검색결과 199건 처리시간 0.03초

합성가스(Reforming gas)를 이용한 멀티채널 CDPF의 재생 특성 연구 (Studies on Reforming Gas Assisted Regeneration of Multi-channel Catalyzed DPF)

  • 최광춘;정진화;송순호;전광민
    • 한국자동차공학회논문집
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    • 제19권3호
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    • pp.138-145
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    • 2011
  • Diesel particulate filter (DPF) systems are being used to reduce the particulate matter emission of diesel vehicles. The DPF should be regenerated after certain driving hours or distance to eliminate soot in the filter. The most widely used method is active regeneration with oxygen at $550{\sim}650^{\circ}C$. Syngas (synthetic gas) can be used to lower the regeneration temperature of Catalyzed DPF (CDPF). The syngas is formed by fuel reforming process of CPOx (Catalytic Partial Oxidation) at specific engine condition (1500rpm, 2bar) using 1wt.% $Rh/CeO_2-ZrO_2$ catalyst. The oxidation characteristics of PM with syngas supplied to filter were studied using partial flow system that can control temperature and flow rate independently. The filter is coated with washcoat loading of $25g/ft^3$ $Pt/Al_2O_3-CeO_2$, and multi-channel CDPF (MC-CDPF) was used. The filter regeneration experiments were performed to investigate the effect of syngas exothermic reaction on soot oxidation in the filter. For this purpose, before oxidation experiment, PM was collected about 8g/L to the filter at engine condition of 1500rpm, bmep 8bar and flow temperature of $200^{\circ}C$ Various conditions of temperature and concentration of syngas were used for the tests. Regeneration of filter started at 2% $H_2$ and CO concentration respectively and inlet temperature of $260^{\circ}C$. Filter Regeneration occurs more actively as the syngas concentration becomes higher.

도시재생 참여 주체로서 도서관의 역할에 관한 연구 (A Study on the Role of Library in Urban Regeneration)

  • 노영희;노지윤
    • 한국비블리아학회지
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    • 제31권1호
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    • pp.89-113
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    • 2020
  • 도시재생사업에서 도서관은 기초생활인프라 중 하나로 필수적으로 고려되어야할 시설이다. 단순한 기초생활인프라로서의 의미를 넘어 도서관이 도시재생의 참여 주체로서 그 기능과 역할을 효과적으로 수행하기 위해서는 기존 도시재생 사업에서 도서관들의 역할 및 성격, 참여형태을 먼저 이해할 필요가 있다. 이에 본 연구는 도시재생사업 관련 전략계획의 내용에서 도서관과 관련된 내용을 조사하고, 도시재생 참여 주체로서의 도서관의 역할과 참여형태 차원에서 고찰하였다. 이를 통해 도시재생의 도서관이 향후 도시재생 참여 주체로서의 그 역할과 기능을 극대화할 수 있는 방향을 모색하고자 하였다. 연구 결과, 도시재생 내 도서관은 주거환경의 질 제고, 도시 활력증진, 생활밀착형 문화적·교육적·사회/복지적 역할, 지역 내 커뮤니티 허브로서의 역할이 기대되고 있다고 볼 수 있다. 또한, 도서관의 참여형태는 크게 지역·지리적 특화도서관, 다양한 서비스와 결합한 하이브리드 도서관, 지역사회 협력과 연계를 기반으로 한 도서관, 주민 참여를 기반으로 한 지역 커뮤니티 허브형 도서관으로 구분해 볼 수 있었다. 향후 도서관은 도시재생의 참여 주체로서 기대되는 5가지 역할을 바탕으로 보다 적극적인 역할 변화를 도모할 필요가 있다. 또한, 도서관이 도시재생 거점시설로서 그 역할을 성공적으로 수행하기 위해 도서관 서비스의 주체인 사서, 서비스, 프로그램 등에 대한 보다 세부적인 논의가 도시재생 계획 수립시에 필요할 것으로 보인다.

백서의 좌골신경에서 정맥 및 골격근을 이용한 결손신경 봉합술에 대한 연구 (A Study in Bridging Sciatic Nerve Defects with Combined Skeletal Muscle and Vein Conduit in Rats)

  • 이준모
    • Archives of Reconstructive Microsurgery
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    • 제6권1호
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    • pp.29-38
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    • 1997
  • A peripheral nerve when approximation of the ends imparts tension at the anastomosis and with a relatively long segment defect after excision of neuroma and neurofibroma cannnot be repaired by early primary suture. The one of the optimistic reconstruction method of severed peripheral nerves is to restore tension-free continuity at the repair site putting an autogenous nerve graft into the neural gap despite of ancipating motor or sensory deficit of the donor nerve area. To overcome the deficit of the autogenous nerve graft, several other conduits supplying a metabolically active environment which is able to support axon regeneration and progression, providing protection against scar invasion, and guiding the regrowing axons to the distal stump of the nerve have been studied. An author have used ipsilateral femoral vein, ipsilateral femoral vein filled with fresh thigh muscle, and autogenous sciatic nerve for the sciatic nerve defect of around 10 mm in length to observe the regeneration pattern in rat by light and electron microscopy. The results were as follows. 1. Light microscopically regeneration pattern of nerve fibers in the autogenous graft group was more abundant than vein graft and vein filled with muscle group. 2. On ultrastructural findings, the proxial end of the graft in various groups showed similar regenerating features of the axons, myelin sheaths, and Schwann cells. The fascicular arrangement of the myelinated and unmyelinated fibers was same regardless of the type of conduits. There were more or less increasing tendency in the number and the diameter of myelinated fibers correlated with the regeneration time. 3. In the middle of the graft, myelinated nerve fibers of vein filled with muscle group were more in number and myelin sheath was thinner than in the venous graft, but the number of regenerating axons in autogenous nerve graft was superior to that in both groups of the graft. The amount of collagen fibrils and amorphous materials in the endoneurial space was increased to elapsed time. 4. There was no difference in regenerating patterns of the nerve fibers of distal end of the graft. The size and shape of the myelinated nerve fbers were more different than that of proximal and middle portion of the graft. From the above results, the degree of myelination and regenerating activity in autogenous nerve is more effective and active in other types of the graft and there were no morphological differences in either ends of the graft regardless of regeneration time.

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지역재생에 있어 지속가능한 마을기업 육성에 관한 연구 - 영국 마을기업 사례를 중심으로 - (A Study on the Promotion of Sustainable Community Enterprise for the Local Regeneration - Focused on Community Enterprises in the UK -)

  • 임정하
    • 대한건축학회논문집:계획계
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    • 제34권5호
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    • pp.139-150
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    • 2018
  • This paper aims to elaborate the role and availability of the community enterprise as a form of methodology in local regeneration, dealing with urban social problems generated in the process of urban development. In a situation of the increasing skepticism in the capitalism, the instability in public welfare system and disintegration of community, social economy has come to the fore as an alternative. The community enterprise, especially, has shown the potential to form a virtuous cycle in local regeneration system; residents recognize local problems by themselves; discover and utilize the local resources and assets in the process of solving the problems as an entrepreneurial form; and consequently create social and economic capital which can be reinvested in the local community. Given these aspects, Korean government has implemented supporting policies for the promotion of community enterprises, and new government's "Urban Regeneration New Deal Project" are putting more importance on the role of social and community enterprises as a propulsion unit. In this regard, this paper first explores the concept and features of community enterprise in economic and social aspects, whereby it analyzes the capacity of community enterprises as principal agencies or implements in local development. Then, the development status and institutional supports for community enterprises in the UK is revealed, and investigates case studies which are playing a revolutionary role in urban regeneration or local economic revitalization. Based on this analysis, it draws the main factors for the sustainable and autogenous community enterprise as follows: flexibility in legal forms, community owned assets, diverse fund streams and invigorating social investment market, active partnership between public and private sectors, ardent enterprisers and intermediate support organizations.

Study of the cartilage matrix production-promoting effect of chicken leg extract and identification of the active ingredient

  • Yamada, Hiroaki;Nakamura, Utano;Nakamura, Toshio;Uchida, Yoshikazu;Yamatsu, Atsushi;Kim, Mujo
    • Nutrition Research and Practice
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    • 제13권6호
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    • pp.480-487
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    • 2019
  • BACKGROUND/OBJECTIVES: Osteoarthritis (OA) is a major public health issue in Japan and other countries, and foods that prevent or treat OA are in strong demand. Proteins and peptides in chicken meat and bones are known for being rich in functional and nutritional ingredients for the improvement of osteoporosis. We speculated that chicken legs, a food consumed in many regions of the world, may also contain such ingredients. In this study, we aim to (i) evaluate the effect of chicken leg extract (CLE) on the promotion of cartilage matrix production and (ii) identify the active ingredient in CLE that contributes to this function. MATERIALS/METHODS: Artificial CLE digest was prepared, and the acid mucopolysaccharide production-promoting activity of the CLE digest was evaluated by alcian blue staining of ATDC5 cells. CLE was orally administered to rabbits with burr holes in the knee joint of the femur, and the degree of regeneration of cartilage matrix was evaluated. Furthermore, we investigated orally administered CLE-derived peptides in human plasma using LC-MS. From measuring the acid mucopolysaccharide production-promotion activity of these peptides, a molecule considered to be an active ingredient in the CLE digest was identified. RESULTS: CLE digest promoted acid mucopolysaccharide production and facilitated regeneration of cartilage matrix in in vitro and in vivo experiments. Four peptides including phenylalanyl-hydroxyproline (Phe-Hyp) were detected as CLE-derived peptides in human plasma. The effect of CLE was inferred to be due to Phe-Hyp, which was confirmed to be present in the CLE digest. CONCLUSIONS: It was shown that CLE stimulated the production of articular cartilage matrix both in vitro and in vivo, and that CLE could be an effective food for preventing or treating OA. Furthermore, only Phe-Hyp was confirmed as the active compound in the CLE digest, suggesting that the activity of CLE was due to Phe-Hyp.

도시재생사업 효과 분석 - 청주시 중앙동을 중심으로 - (Analyzing Urban Regeneration Effects - Focused on Jungang-Dong, Cheongju City -)

  • 한동욱;김태영;주수민;김혜주;홍명기;백종인;반영운
    • 지역연구
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    • 제34권1호
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    • pp.61-75
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    • 2018
  • 도시재생에 관한 연구는 2006년 이래로 10년이 넘는 기간 동안 활발히 진행되어오고 있다. 지금까지 많은 도시 재생사업 효과를 분석하기 위한 연구가 진행되고 있으나 대부분 정성적인 방법에 치우쳐 있다. 따라서 본 연구는 다양한 상업지역 도시재생사업이 진행 중에 있는 청주시 중앙동을 중심으로 도시재생사업의 효과를 정량적으로 분석하는 데 그 목적이 있다. 이를 위하여 유동인구, 공시지가 공실률을 도시재생사업 효과 분석 지표로 선정하였다. 분석시점은 도시재생의 효과가 본격적으로 나타나기 시작한 2013년을 기점으로 2011년부터 2016년까지이다. 분석결과, 첫째, 유동인구는 차츰 증가하다가 프로젝트가 활발히 진행되던 2014년에 약 65퍼센트의 증가율을 보였다. 둘째, 공시지가는 도시재생이 시작한 2011-2012 시점에 가장 큰 증가 폭을 보였고 2015년까지 증가폭이 점차 줄어들면서 2015-2016년에는 미세한 감소를 보였다. 마지막으로 공실률은 꾸준한 하향곡선을 그리며 27퍼센트에서 12퍼센트로 약 15퍼센트포인트가 감소하였다. 본 연구는 상업지역의 도시재생 효과를 정량적으로 분석한데서 학술적인 의의를 찾을 수 있다.

신규 창업점포의 밀도 및 다양성 지표를 활용한 도시재생사업 대상지 평가에 관한 연구 (A Study on the Evaluation of Urban Regeneration Project Sites Using the Density and Diversity Indicators of New Startup Stores)

  • 장성만;박영수
    • 지역연구
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    • 제37권2호
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    • pp.3-16
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    • 2021
  • 본 연구는 도시 재생사업 대상지를 중심으로 신규 창업점포의 밀도 및 다양성 지표를 산출하고, 이를 대조군 그룹과 비교함으로써, 도시 재생사업으로 인한 지역의 활성화 가능성을 평가하였다. 본 연구의 결과는 세 가지로 제시된다. 첫째, 도시 재생사업 대상지의 신규 창업점포의 밀도가 대조군에 비해 높았다. 이를 통해 도시 재생사업은 새로운 유동인구의 유입을 가져올 것이며, 지역 활성화에 긍정적인 요소로 작용할 것이다. 둘째, 도시 재생사업 대상지와 대조군의 신규 창업점포의 업종을 비교하였다. 비교 결과, 도시 재생사업 대상지는 거주자가 아닌 활동 인구를 대상으로 하는 업종의 비율이 높았다. 이는 주간 인구를 유도함으로써, 지역의 활성화를 촉진할 것이다. 셋째, 신규 창업점포의 업종의 다양성을 바탕으로 도시 재생사업 대상지와 대조군을 비교하였다. 분석 결과, 대도시의 도시 재생사업 대상지는 다양한 상품을 판매하는 매장이 밀집되어 있어 소비자를 위한 다목적 쇼핑을 유도할 것이라 기대되며, 소도시의 도시 재생사업 대상지는 유사한 업종이 밀집함으로써, 소비자의 비교 쇼핑을 유도할 것이다.

There-Phase Voltage-Source Soft-Switching Inverter with Auxiliary High Frequency Transformer Linked Power Regeneration Resonant Snubbers

  • Hattori, Hiroshi;Nakaoka, Mutsuo;Sakamoto, Kenji
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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    • pp.153-158
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    • 1998
  • In this paper, a prototype of the auxiliary resonant commutated snubber circuit(ARCS) with a high frequency transformer power regeneration loop is described for voltage source type sinewave inverter system. This is a new soft switching topology developed for three phase voltage source soft-switching inverter, active power filter and reactive power compensator has significant advantage of current rating reduction for auxiliary active switching devices. In addition, this paper presents a novel prototype of voltage-source soft switching space vector-modulated inverter with ARCS mentioned above, which is more suitable and acceptable for high-power utility interactive power conditioning, along with a digital control scheme. The steady-state operating analysis of ARCS has the remarkable features and the practical design procedure of this resonant snubber are illustrated on the basis of computer simulation analysis. The operating performance evaluations in the steady-state of this three phase voltage source soft switching inverter are discussed and compared with the three phase voltage source hard switching inverter.

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유휴공간 관점의 디트로이트 빈집정비 방식의 특성에 관한 연구 (A Study on the Characteristics of Detroit's Improving Empty Homes Method from the perspective on abandoned space)

  • 오준걸
    • 한국산학기술학회논문지
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    • 제17권7호
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    • pp.475-480
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    • 2016
  • 도심의 활력이 떨어짐에 따라 주거지역에서는 빈집이 발생하고 부동산의 개발이 빠르게 이루어지지 못해 버려진 빈집이 유휴공간으로 방치되어 있다. 본 연구의 목적은 유휴공간의 관점에서 빈집의 정의를 바탕으로 디트로이트시의 빈집정비 제도와 방식의 특성을 도출한다. 빈집정비는 근본적으로 도시쇠퇴의 문제해결과 방지를 위함이고, 디트로이트 도시쇠퇴 지역의 빈집정비 특성을 분석하여 우리나라의 빈집정비 현실과 상황에 적용하는 기초자료로 사용하고자 한다. 분석에 따른 디트로이트시의 빈집정비 특성으로는 1. 유휴부지의 조사와 데이터베이스화하는 작업에 주민 참여와 그 데이터를 개방하는 것이 특성으로 나타났다. 2. 유휴부지의 잠재적인 가능성에 따른 재생전략의 다양화를 통한 개발이 특성으로 분석된다. 3. 재생과정의 다원성 확보로 특히 공공과 민간의 역할이 분명하다. 따라서 우리나라에 빈집정비에 적용해야 할 결론으로는 유휴공간의 관점에서 빈집을 주거에 국한시키지 말고 유휴부지도 적극적인 활용에 노력을 기울여야 한다. 또 주민의 참여에 하향식이 아닌 수평적 관계나 오히려 상향식의 참여가 요구된다. 마지막으로 이러한 내용을 포함하는 가이드라인의 작성이 필요하다.

치근이개부 수평결손시 조직재생에 관여하는 전구세포의 면역세포화학적 연구 (THE IMMUNOCYTOCHEMICAL STUDY OF THE PRECURSOR CELLS IN THE PERIODONTAL REGENERATION OF HORIZONTAL FURCATION DEFECT.)

  • 허익;권영혁
    • Journal of Periodontal and Implant Science
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    • 제25권2호
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    • pp.438-457
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    • 1995
  • The origin of fibroblasts, their proliferative activity and roles in the early stages of periodontal regeneration were investigated in order to better understand the periodontal healing process in furcation defects of the beagle dog after guided tissue regeneration. Newly divided cells were identified and quantitated by immunolocalization of bromodeoxyuridine (BrdU) injected 1 hour prior to sacrificing the animals. The results were as follows :1. During periodontal healing in horizontal furcation defect, three different stages, namely the granulation tissue, connective tissue, and bone formation stages, were identified on the basis of major types of cells and tissue. 2. In the early stages of periodontal regeneration, both the remaining periodontal ligament and alveolar bone compartment were the major sources. 3. The majority of BrdU-labeled fibroblasts were located at the following areas ; 1) the coronal zone of the defect in case of the connective tissue fanned on the root surface. 2) the area within an 400 ${\mu}m$ distance from the remaining bone level in case of the periodontal ligament. 3) the area within an 100 ${\mu}m$ distance from the bone surface in case of areas of active bone formation.4. The highly proliferative fibroblasts adjacent to bone surface played a major role in the formation of osteoblast precursor cells, whereas both paravascular and endosteal cells played a minor role in new bone formation, In conclusion, it was suggested that the fibroblasts in the remaining periodontal ligament and bone will play a major role in periodontal regeneration, whereas both paravascular and endosteal cells will play a minor role in new bone formation.

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