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281.
The energy balances published by the International Energy Agency (IEA) are one of the most valuable sources of energy statistics covering world energy supply and demand. However, some issues arise when these data are analyzed or used directly. Even when industrial energy consumption alone is examined, at least three types of issues are encountered: missing data, large amounts of misallocated data in some countries, and numerous unrealistic outliers in the time-series variations. When we deal with only a few regions, we can look at data one by one and modify them. In this case, we are going to overcome these issues with a systematic method because the data covers world including more than a hundred regions.This paper proposes a data reconciliation method to treat these issues, and describes its application to world industrial energy consumption. As a result of its application, we found that the three issues mentioned above seemed to be overcome. The degree of the reconciliation by region showed that OECD countries' degree tends to be smaller than those of non-OECD countries. However, not all of the OECD countries have low values and some countries, such as the United States, have high values. 相似文献
282.
H. Suzuki M. Okada W. Lin S. Morita Y. Yamagata H. Hanada H. Araki S. Kashima 《CIRP Annals》2014,63(1):313-316
Needs of micro structured optical components are increasing in the astronomical space telescope. In the space having extremely large temperature differences, a diffractive optical element (DOE) lens is very effective in reducing the thermal chromatic aberration due to the thermal expansion. In order to finish the ground DOE lens of synthetic silica, a magnetic field-assisted polishing is proposed. In the experiments, DOE lens ground by the sharp edged diamond wheel is finished by the magnetic field-assisted polishing. By the grinding and polishing test, changes of form deviation profiles and surface roughness profiles are evaluated and feasibility is tested. 相似文献
283.
The SSU1-R gene provides high sulfite resistance to the wine yeast Y9-16B. In this study, we examined the distribution of this gene in 61 wine yeasts and 4 laboratory yeasts. We also analyzed the number of repeats of a 76-bp promoter sequence and its relationship to sulfite resistance. We found that the SSU1-R gene was present in 31 of the 61 wine yeasts. Furthermore, we found that the number of repeats in the promoter region of SSU1-R varied from two to six. Using RsaI, which cuts only once in the repeat, we suggested that the repeats all consisted of the 76-bp sequence. Finally, we found that there was a complex relationship between the number of repeats and sulfite resistance. 相似文献
284.
Hamamatsu N Nomiya Y Aita T Nakajima M Husimi Y Shibanaka Y 《Protein engineering, design & selection : PEDS》2006,19(11):483-489
We assumed that adverse effects posed by introducing multiple mutations could be decomposed into those of each of the component mutations and that the risk could be reduced by the accumulation of mutations that were finely tuned for directed improvement of a specific property. We propose here a directed evolution strategy for improving a specific property with less effect on other ones. This strategy is composed of fine-tuning of mutations and their accumulation by our original mutation-assembling method. In this study, we selected lactate oxidase (LOX) as a model enzyme, because its directed evolution had showed a trade-off between thermostability and catalytic activity. Mutation profiling at each of the sites found by error-prone PCR revealed a strong inverse relationship between the two properties. Thermostable mutations with less effect on catalytic activity were selected at each site and accumulated with ideal combinations by our method. The resultant multiple mutants exhibited 5- to 10-fold superior catalytic activity and comparable thermostability with those created by accumulating thermostable mutations, which were not tuned for catalytic activity. This result demonstrates that the accumulation of fine-tuned mutations is an advantageous approach to reduce the risk of adverse effects posed by accumulating multiple mutations. 相似文献
285.