• Title/Summary/Keyword: change of composition

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Heavy Metal Adsorption Characteristics of Extracellular Polysaccharide Produced by Zoogloea ramigera Grown on Various Carbon Sources

  • Kim, Se-Kyung;Lee, Choul-Gyun;Yun, Hyun-Shik
    • Journal of Microbiology and Biotechnology
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    • v.13 no.5
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    • pp.745-750
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    • 2003
  • Zoogloea ramigera produces an extracellular polysaccharide called zooglan, which adsorbs heavy metals. In the current study, Zoogloea ramigera was cultured in media containing various carbon sources. When different carbon sources were included in the cultivation medium, there was a change in the composition of zooglan that is mainly composed of glucose, galactose, and pyruvic acid. The various zooglan compositions were analyzed by HPLC, and changes in the heavy metal (lead (II) and cadmium) adsorption characteristics relative to a change in the composition were examined using an atomic absorption spectrophotometer. A high adsorption capacity was observed at a pH higher than 3.0. The adsorption of metal ions was the highest at $35^{\circ}C$, and a higher adsorption was obtained with a lower flow rate. Changes in the zooglan composition did result in changes in the heavy metal adsorption characteristics. Furthermore, it was also found that the pyruvic acid content was more important than the glucose or galactose content for heavy metal adsorption.

GMA Torch Configuration for Efficient Use of Argon Gas Part 1 : Effects of AMAG and DMAG Torches on Argon Composition (아르곤 가스를 효율적으로 사용하기 위한 GMA 용접 토치 구조 Part 1 : AMAG와 DMAG 토치가 아르곤 조성에 미치는 영향)

  • 최상균;문명철;유중돈
    • Journal of Welding and Joining
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    • v.17 no.6
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    • pp.38-45
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    • 1999
  • Shielding gas has significant effects on arc stability, metal transfer and weld quality in the gas metal arc welding (GMAW) process. The double gas-shielded MAG(DMAG) and auxiliary gas-shielded MAG (AMAG) torches are investigated for their capability to provide argon-rich gas mixture using small amount of argon gas through the inner and auxiliary nozzles, respectively. Argon composition with the DMAG torch is calculated numerically, and compared with the measured data using the gas chromatogrphy. Gas flow pattern of the DMAG torch is calculated to change from the laminar to turbulent flow when total gas flow rate becomes larger than 4.5 liter/min at room temperature. While argon-rich shielding gas was obtained using both the AMAG and DMAG torches, the AMAG torch provides higher argon composition than the DMAG torch, which demonstrates that argon gas can be utilized more efficiently with the AMAG torch.

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Seasonal fluctuations and changing characteristics of a temperate zone wetland bird community

  • Lee, Soo-Dong;Kang, Hyun-Kyung
    • Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.104-116
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    • 2019
  • Background: The composition of wild bird populations in temperate zones greatly varies depending on phenological changes rather than other environmental factors. Particularly, wild birds appearing in wetlands fluctuate greatly due to the crossover of species arriving for breeding during the summer and for wintering. Therefore, to understand the changes to species composition related to phenology, we conducted this basic analysis of populations to further the cause of the protection of wetland-dependent wild birds. Methods: It is wrong to simply divide a wild bird population investigation into seasons. This study identifies species composition and indicator species that change along with seasons. Wetlands to be surveyed are protected by natural monuments and wetland inventory and are in a state close to nature. In order to identify as many species as possible in wetlands, a survey was conducted in both shallow and deep wetlands. The water depth varied in these areas, ranging from 0.2 to 2.0 m, allowing for both dabbling and diving ducks to inhabit the area. Surveys were conducted using line-transect and distance sampling methods and were conducted at intervals of 2 weeks. The survey was conducted under the following three categories: the eco-tone and emergent zone, the submergent zone, and the water surface. The survey was conducted along a wetland boundary by observing wild birds. A PC-ord program was used for clustering, and the SAS program was used to analyze the changes in species composition. The data strongly indicates that day length is the main factor for seasonal migration periods, despite the fact that climate change and increasing temperatures are often discussed. Results and conclusions: The indicator species for determining seasons include migrant birds such as Ardea cinerea, Alcedo atthis, Anas penelope, and Poiceps ruficollis, as well as resident birds such as Streptopelia orientalis and Emberiza elegans. Importantly, increases in local individual counts of these species may also serve as indicators. The survey results of seasonal fluctuations in temperate zones shows that spring (April to June), summer (July to September), autumn (October), and winter (November to March) are clearly distinguishable, even though spring and summer seasons tend to overlap, leading to the conclusion that additional research could more clearly identify fluctuation patterns in species composition and abundance in the study area.

An Approach to Application of Component Based on Message Central Processing change the C2 Architecture (C2 아키텍처를 변형한 메시지 중앙처리 기반의 Component 활용 기법)

  • 정화영
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.5
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    • pp.1089-1094
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    • 2003
  • Recently, Software development method supported CBD is applied with many concern and is researched with part of application and composition based-on architecture effectively use it. Effectively, C2 architecture has been concern with the point of component composition method based-on message driven for supported GUI. But, In case of classified sequence in component and method call method in server component, component must be modified to apply it. Thus, In this paper, Message handling part with a part of C2 architecture change is locate in the message neither component not connector. So, Although method call method it can be composit and operate component for support Plug-and-Play without modification. Also, it's possible the more flexible message handling with parallel composition of component between message without classified sequence.

Application Advanced One-Sided Stress Wave Velocity Measurement in Concrete (콘크리트에서의 One-Sided 응력파 속도 측정 기법의 적용에 관한 연구)

  • ;;J.S.Popovice;J.D.Achenbach
    • Proceedings of the Korea Concrete Institute Conference
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    • 1997.04a
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    • pp.544-550
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    • 1997
  • In this study, the advanced on-sided stress wave velocity measurement method was applied to investigate the effects of composition, age and moisture content in concrete. Two concrete specimens that have different composition were used to figure out the change of the Longitudinal and Surface wave velocity due to different composition. The other concrete specimen was cast and the Longitudinal and Surface wave velocity was monitored during curing process. After 28-day old, the effect of moisture content in the concrete specimen to the stress wave velocity is presented in this paper during the time period 43-74 days after casting. For drying process. an aggregate drying oven was used. A conventional ultrasonic through transmission method was used to compare with the results determined by the one-sided method.

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A Study on the Satisfaction of Spatial Composition by Double-income Households Considering their Life Style (맞벌이가족 라이프스타일 유형에 따른 공간구성 만족도에 관한 연구)

  • Lee, Se-Na;Lee, Hyun-Soo
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2006.11a
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    • pp.92-96
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    • 2006
  • With the change of family type and diversify of life style, residents need various unit plan in Quality. A rate of economically productive women has increased, and generally double-income households will continuously increase in the future. So a research is requested to consider the double-income households's satisfaction for a unit plan based on their life characteristics. The purpose of this study is to find out double-income households's lifestyles, and to search and analyze users' needs for spatial composition according to their lifestyles, and then, embody spatial composition of Apartment Unit plans. The findings are as follows. (1) Housing lifestyles of users living in apartment are categorized into 5 types: seeking the way to make housework easy and comfortable, making the best use spatial composition, pursing the universalism, housework oriented, pursing the leisure. (2) The type of seeking the way to make housework easy and comfortable requests facility with home appliances and a shower bath, the type of making the best use spatial composition requests storage space and trial about new plan, the type of pursing the universalism is concerned about the protection of environment and a memorial service, the type of housework oriented wants a talk with their family and discuss some problem, and the type of pursing the leisure requests division of household with their family and likes traveling and sports.

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Total Lipid, Total Cholesterol and Fatty Acid Composition in Colostrum from Mothers with Preterm Delivery and Pregnancy Induced Hypertension (조기분만과 임신성 고혈압 산모의 초유내 총지질, 총콜레스테롤 및 지방산 조정)

  • 안홍석
    • Journal of Nutrition and Health
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    • v.33 no.2
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    • pp.186-192
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    • 2000
  • In this study, total lipid and cholesterol contents and fatty acid composition of colostrum milk obtained from 30 normal mothers, 10 mothers who was delivered of preterm infant and 8 pregnancy induced hypertensive mothers were analyzed. While total cholesterol content in preterm colostrum was significantly lower than other groups (p<0.05), total lipid content was not different among three groups, ranged 2.24-.2.2g/dl. Composition of saturated fatty acide, such as lauric acid and myristic acid which are medium chain fatty acids in preterm milk were higher than those of normal-term and hypertensive mother's milk. There was no difference n total composition of polyunsaturated fatty acids and the rationh of $\omega$6/$\omega$3 among 3 group mother's colostrum, ranged 19.45-21.45% and 6.42-7.87, respectively. but the composition of arachidonic acid and DHA in colostrum of hypertensive mothers were significantly higher than those of normal and preterm mothers. These data indicates that gestational length and complications during pregnancy may change the lipid profile and fatty acid composition of hyman milk colosstrum.

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A Dynamic QoS Adjustment Enabled and Load-balancing-aware Service Composition Method for Multiple Requests

  • Wu, Xiaozhu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.3
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    • pp.891-910
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    • 2021
  • Previous QoS-aware service composition methods mainly focus on how to generate composite service with the optimal QoS efficiently for a single request. However, in the real application scenarios, there are multiple service requests and multiple service providers. It is more important to compose services with suboptimal QoS and maintain the load balance between services. To solve this problem, in this paper, we propose a service composition method, named as dynamically change and balancing composition method (DCBC). It assumes that the QoS of service is not static, and the services can adjust the value of QoS to gain more opportunities to be selected for composition. The method mainly includes two steps, which are the preprocessing step and the service selection step. In the preprocessing step, a backward global best QoS calculation is performed which regarding the static and dynamic QoS respectively; then guided by the global QoS, the feasible services can be selected efficiently in the service selection step. The experiments show that the DCBC method can not only improve the overall quality of composite services but also guarantee the fulfill ratio of requests and the load balance of services.

Effect of DHA and Environmental Enrichment on Brain Fatty Acid Composition and Acetylcholinesterase Activity (식이 DHA와 환경보충이 흰쥐의 뇌지방조성 및 Acetylcholinesterase활성에 미치는 영향)

  • 김문정
    • Journal of Nutrition and Health
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    • v.29 no.1
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    • pp.32-40
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    • 1996
  • To investigate the effect of dietary docosahexaenoic acid(DHA) and environmental enrichment on brain fatty acid composition and acetylcholinesterase(AChE) activity, two groups of was fed isocaloric diets containing 10 or 12% dietary lipids for 7 weeks. A third group was fed 10% (w/w) dietary lipids with supplemented 2% DHA-rich fish oil. Each diet group was housed either in a stainless steel cage individually or in a large enriched cage with toys where 7 rats were kept together. The fatty acid composition of plasma and brain was significantly affected by dietary lipid composition but not by environmental enrichment. Fish oil supplementation significanlty decreased plasma levels of monounsaturated fatty acids(MUFA) and increased polyunsaturated fatty acids(PUFA). Fish oil supplemented groups also maintained lower plasma n-6 fatty acids and higher n-3 fatty acids levels than unsupplemented groups. The fish oil supplementation significantly decreased arachidonic acid and increased eicosapentaenic, docosapentaenoic acids, and DHA in brain fatty acid composition. In addition, brain DHA level in supplemented groups tended higher than the unsupplemented. Brain, AChE activity significantly increased by the environmental enrichment but not by the fish oil supplementation. These finding suggest that the 2% fish oil (0.57% DHA & 0.31% EPA, per diet weigth) supplementation is enough to accumulate n-3 fatty acids and to change the n-6 n-3 ratio in brain and environmental enrichment might promote the learning ability.

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Structure of the consumption expenditure by income bracket -Comparative analysis before and after IMF- (도시가계의 소득계층별 소비지출구조 분석 - IMF이전과 이후 비교분석 -)

  • 소연경
    • Journal of the Korean Home Economics Association
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    • v.38 no.12
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    • pp.1-14
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    • 2000
  • The purpose of this study is to identify the change according to income bracket and the trade-off between expenditure items by analyzing expenditure patterns of the urban households as a reset of the IMF. The results of this study are as follows; The composition percentage and the amount of consumption expenditure of urban households after IMF decrease in all classes. But the change of composition percentage by the decrease of consumption expenditure is different in every class. The percentage of decrease of the upper class is higher than that of the lower class in an essential expenditure of household, which is food. And the percentage of decrease of the lower class is higher than that of the higher class in the discretionary expenditures such as clothes and education.

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