• Title/Summary/Keyword: Regeneration ratio

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Spatial Regeneration for Preservation of Historic Urban Features and Improvement of Living Conditions in High-density Historic Districts: Urban Renewal Design Strategies for Shanghai's Old Town

  • Huang, Na;Cai, Yongjie;Zhuang, Mingyu;Zhou, Yi;Zhou, Jun
    • International Journal of High-Rise Buildings
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    • v.10 no.1
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    • pp.9-16
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    • 2021
  • Being the origin of Shanghai City, the Old Town presents a high-density spatial texture, a characteristic of local living conditions in the Shanghai context. However, the Old Town is faced with competing interests: the preservation of historic urban features and the improvement of contemporary living conditions. In view of its high density and poor living conditions, this paper focuses on two types of blocks for urban design research, and proposes two spatial regeneration strategies, as "overlapping lilong" and "texture continuity". It is expected to inherit the regional characteristics of urban space, improve the plot ratio and supplement the mix of functions, through the translation of the traditional lilong typology and the reproduction of historical streets and alleys, so as to provide operable spatial strategies and design methods for the organic renewal of Old Town and other historic districts.

The Effect of Tidal Cycle and River Runoff on the Dynamic of Nutrients in Keum river estuary (금강하구역에서 영양염 거동에 대한 조석 및 담수유출의 영향)

  • Kim, Jong-Gu;Kang, Hoon
    • Journal of Environmental Science International
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    • v.11 no.6
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    • pp.519-528
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    • 2002
  • This study was to evaluate the impact of river runoff and salt intrusion by tide on nutrient balance of estuary during a complete tidal cycle. 24 hours time series survey was carried out during a spring tide July 2001 on a tidal estuary in the Keum river. Three stations(A,B,C) were set along a transect line of about 10km, which linked the lower part of estuary dyke to the subtidal zone. Surface water was sampled simultaneously at each station every hours f3r the determination of nutrients. Water temperature, pH and dissolved oxygen were measured in situ. Riverine input of silicate and nitrate during ebb tide significantly increased the concentration of all stations. Conversely, during high tide, nutrient concentration were lowered by the mixing of fresh water with sea water Ammonium nitrogen concentration were higher at intertidal zone(Stn.B) due to sewage inflow to Kyeongpo stream and ammonium release under anaerobic conditions. Also, these results was discussed as a biological component that influences the processes of nutrient regeneration within the estuary. Best correlations were found at lower part of estuary dyke(Stn.A) for salinity against DIN(Y=0.121 Sal.+4.97, r2=0.956) and silicate(Y=0.040 Sal.+2.62, r2=0.785). But no significant correlation was found between salinity and ammonium. Unbalanced elemental ratio(N/P, Si/N and Si/P) depended significantly on the import of nutrients (silicate & nitrate nitrogen) from river and stream. The effect of the tidal cycle and river runoff is important that in determining the extend of the variations in nutrient concentrations at all station.

Selective Separation of Hydrogen from Gas Mixture using LaNi5 (LaNi5를 이용한 혼합기체로부터 수소의 선택적 분리)

  • Sun, Yang Kook;Nahm, Kee Suk;Lee, Wha Young
    • Transactions of the Korean hydrogen and new energy society
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    • v.1 no.1
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    • pp.15-23
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    • 1989
  • The selective separation of hydrogen from gas mixture containing hydrogen was experimentally studied using $LaNi_5$. The capacity and the rate of hydrogen separation, the purity of recovered hydrogen and the optimum condition of the regeneration of deactivated $LaNi_5$ were investigated. The separation rate and the recovery ratio of hydrogen were slowly decreased with the increase of the number of hydrogen absorption cycle. It was found that this result comes from the deactivation of $LaNi_5$ partly because of the blocking of hydrocarbon compounds in the $LaNi_5$ lattice and partly because of the poisoning of $LaNi_5$ surface by carbon monoxide contained in the gas mixture. The optimum condition for the regeneration of deactivated $LaNi_5$ was obtained by heating in a vacuum to about 637 K. The recovery ratio of hydrogen at the optimum condition was observed to be about 80%. The rates of hydrogen separation were measured in the ${\alpha}$-phase and two phase regions. The rate equations could be expressed as follows ; ${\alpha}$ - phase : $$-\frac{dP{_{H_2}}}{dt}=9.836{\times}10^{-3}(P{_{H_2}}_{-P_{eq}})$$ two phase region : $$-\frac{dP_{H{_2}}}{dt}=1.6909{\times}10^2\exp(-17560/RT)(P{_{H_2}}_{-P_{eq}})$$.

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The biologic effects of magnoliae cortex extract and safflower seed (Carthamus tinctorius $Linn{\acute{e}}$) extract mixture on PDL cells and osteoblasts (후박 및 홍화종자 추출혼합물이 치주인대세포 및 골아세포의 활성도 및 백서의 두개골재생에 미치는 영향)

  • Shin, Seung-Yun;Lee, Yong-Moo;Ku, Young;Bae, Ki-Hwan;Chung, Chong-Pyoung
    • Journal of Periodontal and Implant Science
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    • v.28 no.4
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    • pp.545-559
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    • 1998
  • Magnoliae cortex has been used as a drug for treatment of fractures in Chinese medicine and safflower(Carthamus tinctorius $Linn{\acute{e}}$) has been traditionally used for treatment of blood stasis. The purpose of present study was to examine the biologic effects of magnoliae cortex extract and safflower extract mixture(MSM) on human periodontal ligament cells and fetal rat calvarial osteoblasts and on healing of rat calvarial defects. The ethanolic extracts of magnoliae cortex(MCE), safflower seed(SSE), Zea May L(ZML) were prepared as positive control group. MSM mixed to the ratios of 1 : 1, 1 : 2, 1 : 5 and 1 : 10 were used as test group. The effects of each agents on the growth and survival, ALPase activity, cell proliferation and tissue regenerative effect of each extracts was evaluated by histomorphometric measuring of newly formed bone on the 8 mm defect in rat calvaria after oral administration of 2 ratio groups(1 : 5 and 1 : 10) at 3 different doses (0.1, 0.25 and 0.5g/kg per day). MSM stimulated the growth and survival rate of osteoblasts and PDL cells more than any other agents. The growth and survival rate were increased as the proportion of safflower seed extract was increased. MCE, SSE, ZML stimulated the ALPase activity of osteoblast and PDL cell in comparison to the negative control group. But all groups of MSM regardless of ratio of safflower seed extract stimulated the ALPase activity than any other agent. The ALPase activity was also increased as the proportion of safflower seed extract was increased. Although MCE, SSE, ZML stimulated the proliferation of osteoblasts. 1 : 5 and 1 : 10 ratio MSM showed significant increase in stimulation of proliferation of osteoblasts. No agent significantly increased proliferation of PDL cells. Significant new bone formation were seen where 1 : 5 ratio, 0.5g/kg group and 1 : 10 ratio, 0.25, 0.5g/kg groups were used. These results show that magnoliae cortex extract and safflower seed extract mixture can potentially increase bone regeneration ability.

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An Analysis of the Effects of Customer Characteristics on Sales of Alley Market Area Using Geographically Weighted Regression (지리가중회귀분석을 이용한 고객특성별 골목상권 매출액 영향 연구)

  • Kang, Hyun Mo;Lee, Sang-Kyeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.6
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    • pp.611-620
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    • 2018
  • With the revitalization of alley market area becoming a major goal of the urban regeneration project, an understanding on customer characteristics that affect the sales of alley market areas is needed. As spatial heterogeneity appears to exist in alley market areas, the use of GWR (Geographically Weighted Regression) is required as an alternative to OLS (Ordinary Least Squares) regression. This study analyzes effects of customer characteristics on sales of 1007 alley market areas in Seoul. Comparing R squared and AICc, results show that GWR is better than OLS regression. According to OLS regression, the ratio of female, the ratio of 40's and 50's, the number of employees, the opening rate of establishment, the density of building and the size of alley market area have positive effects on sales, while the ratio of 20's and 30's, the distance of bus stop and that of subway station have negative effects. As a result of comparing local regression coefficients of geographically weighted regression analysis, the ratio of female customers has the greatest effect on the northwestern region, followed by the southwestern region, the central region and the northeastern region. The ratio of 20's and 30's and that of 40's and 50's effect on the southeastern and northeastern regions, and then the southwestern region. It is expected that this study will help to identify marketing target for each alley market area.

Performance characterization of liquid desiccant system with extended surface (확장표면을 적용한 액체식 제습시스템의 성능특성에 관한 연구)

  • Jang, Young-Soo;Song, Gwi-Eun;Lee, Dae-Young
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.639-644
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    • 2009
  • This study presents the new idea of liquid desiccant system with extended surface to reduce the system size. The extended surface is inserted between vertical cooling/heating tubes to increase the mass transfer area, and the liquid desiccant flows through the tube wall and the extended surface. Mathematical models for heat and mass transfer between liquid desiccant and air stream at tube wall and extended surface are provided. Dimensionless design parameters governing heat and mass transfer phenomena around the tube and the extended surface are identifier, and dimensionless operating parameters depicting system operating condition including flow rate ratio between dehumidification/regeneration processes, and mass flow rate ratio between air stream and liquid desiccant are explained. The effects of the parameters on system performance are summarized.

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Development of a Linearized Model and Verification of the Exact Solution for the Analysis of a Desiccant Dehumidifier (제습기 성능분석을 위한 선형화 모델 및 해석해의 검증)

  • 이길봉;이대영;김민수
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.9
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    • pp.811-819
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    • 2004
  • A silica gel desiccant dehumidifier is studied theoretically in this paper adopting several linearization assumptions. The governing equations are linearized with the assumptions, and the exact solutions to the temperature and the humidity ratio are obtained. In spite of the assumptions, the theoretical results are found to agree well with those from the numerical analysis without any assumption. In typical operation ranges of the desiccant dehumidifier, the time-averaged errors in the process air temperature and humidity ratio are less than 4% and 7%, respectively, and the corresponding root-mean-square values are less than 5% and 15%, respectively The analytical solutions are expected to contribute to the fundamental understanding of the dehumidification and regeneration processes and the correlation analysis of the numerous parameters influencing the dehumidifier operation.

Production of New Regenerated Plants by Anther Culture of the Hybrids of Italian ryegrass X Tall fescue (이탈리안 라이그라스 X 톨페스큐 속간 교잡종의 약배양 기법을 이용한 식물체 생산)

  • Kim, K.Y.;Kang, K.M.;Choi, K.J.;Jang, Y.S.;Lim, Y.C.;Kim, M.J.;Kim, J.G.;Kim, W.H.;Park, G.J.
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.22 no.4
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    • pp.273-278
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    • 2002
  • Several regenerated plants were obtained from anther culture of the hybrid lines of Italian ryegrass (Lolium multiflorum Lam.) X Tall fescue (Festuca arundinacea Schreb.). When the anthers of the hybrid plants were incubated for 20 days on callus induction medium, MS medium containing 30 g/$\ell$ of sucrose, 2 mg/$\ell$ of NAA and 1 mg/$\ell$ of kinetin, their calli were induced. The mean ratio of callus induction was 11.6 percent, and the mean of callus weight was 9.1 mg/callus/anther. When the calli of the hybrid plants were incubated for 50 days on plant regeneration medium, MS medium containing 30 g/$\ell$ of sucrose, 1 mg/$\ell$ of NAA and 2 mg/$\ell$ of kinetin, the hybrid plants were regenerated. The mean ratio of plant regeneration was 27.1 percent and line Hyb-1 showed highest regenerabillity with the frequency of 30.2 percent.

Experimental Study on the Characteristics of CO2 Capture with Spray Towers Using Ammonia Solution (암모니아수 흡수제를 사용하는 분무탑의 이산화탄소 포집 기본특성에 관한 실험적 연구)

  • Lim, Youngbok;Choi, Munkyoung;Lee, Jinwon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.38 no.2
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    • pp.165-172
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    • 2014
  • Experiments were conducted to identify basic characteristics of $CO_2$ capture using a spray tower with a single nozzle. Results were evaluated in terms of $CO_2$ saturation which is the main determining factor of regeneration energy, and capture efficiency under various operating conditions. Changes in the capture efficiency under various conditions are well expressed as a monotone increasing function of the relative solvent $(NH_3):CO_2$ flow rate. Although changes in $CO_2$ saturation are also well described as a function of the $NH_3/CO_2$ flow rate ratio, these are expressed as a monotone decreasing function, in contrast with the increasing function of $CO_2$ efficiency. In recent research on the relationship between $CO_2$ saturation and capture efficiency, $CO_2$ saturation was found to decrease when capture efficiency increased. In conclusion, the results show that the amount of solvent used for achieving high capture efficiencies is excessive, as is the amount of regeneration energy needed.

Plant Regeneration by in vitro Tissue Culture in Korean Soybean (Glycine max L.) (기내 배양을 통한 국내 콩(Glycine max L.) 품종의 식물체 재분화)

  • Kim, Dong-Gun;Kantayos, Vipada;Kim, Dong-Kwan;Park, Heung-Gyu;Kim, Haeng-Hoon;Rha, Eui-Shik;Lee, Sheong Chun;Bae, Chang-Hyu
    • Korean Journal of Plant Resources
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    • v.29 no.1
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    • pp.143-153
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    • 2016
  • Plant regeneration via organogenesis and somatic embryogenesis was investigated in Korean soybean cultivars including Cheongja 3, Jinpumkong 2, Taekwangkong and Uram. Cotyledon, cotyledon+hypocotyl and hypocotyl segments of 7-day-old seedlings were cultured on MS medium containing various concentration (0, 1, 2 and 4 ㎎/L) of BA and TDZ. The results showed that MS medium supplemented with BA 2.0 ㎎/L yielded the highest shoot formation ratio of 83.3%. In 4 cultivars, Taekwangkong showed the highest ratio of shoot formation. When various sizes of immature cotyledons (S: 1∼ 2 ㎜, M: 3∼5 ㎜, L: 6∼8 ㎜) were tested on MS medium containing 2,4-D 40 ㎎/L for somatic embryogenesis, the optimum size for embryogenic callus induction was 3∼5 ㎜ in length of immature cotyledons. In 4 cultivars, Taekwangkong showed the highest percentage of embryogenic callus induction. The results indicate that Taekwangkong is the best soybean cultivar for plant regeneration via organogenesis and embryogenic callus induction among the 4 cultivars.