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41.
Y S Cao C M Ang K S Raajeevan A K Kiran K C Lai S W Ng I Zulkifli Y L Wah 《Water science and technology》2006,54(8):237-246
This paper analyses the performance of the anaerobic selector (A/O process) in a full-scale activated sludge process receiving mostly industrial sewage discharge (> 60%) in Singapore. In addition to the sludge settleability, enhanced biological phosphorus removal (EBPR) was studied. The sludge volume index (SVI) reduced from 200 to 80 ml g(-1) and foaming was suppressed significantly, indicating the effectiveness of the anaerobic selector in improving sludge settleability. The phosphorus removal efficiency was 66%, and 7.5 mg HAc-COD was consumed per mg PO4(3-) -P removed. In the anaerobic compartment, 31% of the SCOD and 73% of the acetic acid in the settled sewage were removed with PO4(3-) -P release of 14.1 mg PO4(3-)-P l(-1). The linear correlation between PO4(3-) -P release in the anaerobic compartment and PO4(3-) -P uptake in the aerobic compartment indicates that there is about 0.8 mg PO4(3-) -P release in the anaerobic compartment per mg PO34(3-) -P uptake in the aerobic compartment. The fates of volatile fatty acids (VFAs) and its short chain acids (SCAs) in the process were studied and discussed. 相似文献
42.
At the present time, organic solid wastes from industries and agricultural activities are considered to be promising substrates for biogas production via anaerobic digestion. Moreover solids stabilisation is required before reutilization or disposal. Slaughterhouses are among the most important industries in Uruguay and produce 150,000 tons of ruminal content (RC) and 30,000 tons of blood per year. In order to determine the influence of the solids and blood contents, the ammonia inhibition and the inoculum adaptation co-digestion batch tests were performed. A set of experiences with TS concentration of 2.5%, 5% and 7.5% and different ratios of RC/blood were carried out using an inoculum from an UASB reactor. In all experiences fast blood hydrolisation was observed. A higher methane production was detected in the experiences with higher TS content. However, the fraction of solids degradation was lower in these experiences. A plateau in the biogas production was found. The free ammonia level, which was above the reported inhibitory levels, could explain this behaviour. After the inhibition period the biogas production restarted probably due to the biomass acclimatisation to the ammonia. In order to determine the inoculum adaptation a new experiment was performed. The inoculum used was the sludge coming from the first set of experiences. Based upon batch tests a 3.5 m3 pilot reactor was designed and started up. Ammonia inhibition was avoided by the start-up strategy and in two weeks the biogas production was 3.5 m3/d. The VS stabilisation with a solid retention time of 20 days was of 43%. The pilot reactor working at steady state had a TS concentration of 3-4% with a ratio of RC/blood of 10:1 at the entrance. 相似文献
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44.
Marketing online banking services: The voice of the customer 总被引:1,自引:1,他引:0
US banks have invested heavily in developing online capabilities, with the expectation of migrating customers to the new cheaper delivery system. Results in the USA thus far have been mixed at best; market penetration is low and customer usage is sporadic, focusing mainly on simple tasks. This paper reports on the first of two studies conducted to investigate the reasons for the mediocre performance. A qualitative consumer study revealed significant differences in attitudes and opinions between early users and those that banks hope will adopt next. Most importantly, future prospects could be characterised as indifferent about online banking; many were not convinced about its benefits and the value it provides. While the potential to expand the market for online banking services exists, banks need to re-examine their marketing approach. 相似文献
45.
Differences between bank employees' perceptions towards implications of electronic banking in Greece
Konstantinos Lymberopoulos Ioannis E Chaniotakis 《Journal of Financial Services Marketing》2003,8(1):35-47
This paper aims to identify both the Greek branch and the central division employees' perceptions towards implications of electronic banking adoption and explore whether there are any differences between them. To this end, based on 14 potential implications recognised in the literature review, a questionnaire was designed and completed by 613 bank employees. The analysis showed that perceptions vary in relation to respondents' working position. Additionally, there are indications that the identified differences are greater if they are linked with the respondents' working experience and educational qualifications, as well as the size of the financial institution. In conclusion, the paper discusses the strategic implications of the findings. 相似文献
46.
Jay Ginn 《Journal of Financial Services Marketing》2003,7(4):319-329
Present policy means that a private pension, unless it is substantial, may fail to bring financial gain in retirement due to means testing: the pensions poverty trap. This paper examines women's acquisition of private (occupational and personal) pensions and their risk of facing this trap. Because of the loosening link between marriage and motherhood, previous patterns of pension advantage according to marital status are shifting. The employment and pension impact of motherhood varies with socio-economic status but the pension prospects of the majority of women are poor. It is concluded that women's need for financial advice to avoid the pensions poverty trap is greater than men's. An improved basic pension, indexed to national income, would reduce the risk of mis-selling and restore confidence that saving for a pension is worthwhile. 相似文献
47.
The paper argues that although considerations such as industry consolidation, the role of lending and the effects of technology are still important in shaping the future of investment banking, sustainable competitive advantage necessitates that emphasis is also placed on thought leadership. This entails quite a radical change in terms of the way in which the industry approaches the problem of competition and requires emphasis on value creation for all the constituent parts of the industry: corporations, investors, the banks themselves and research departments. Accordingly, the paper provides a rationale for this change and provides inter alia a range of examples to illustrate how thought leadership could lead to a fundamental change in the future of the investment banking industry. 相似文献
48.
A play-the-winner-type urn design with reduced variability 总被引:1,自引:0,他引:1
Anastasia Ivanova 《Metrika》2003,58(1):1-13
We propose a new adaptive allocation rule, the drop-the-loser, that randomizes subjects in the course of a trial comparing
treatments with dichotomous outcomes. The rule tends to assign more patients to better treatments with the same limiting proportion
as the randomized play-the-winner rule. The new design has significantly less variable allocation proportion than the randomized
play-the-winner rule. Decrease in variability translates into a gain in statistical power. For some values of success probabilities
the drop-the-loser rule has a double advantage over conventional equal allocation in that it has better power and assigns
more subjects to the better treatment.
Acknowledgments. I thank Stephen Durham, the associate editor, and the referees for their helpful suggestions. 相似文献
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