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排序方式: 共有1601条查询结果,搜索用时 18 毫秒
1.
David L. Wood Jeffrey D. Quass Jianlin Li Shabbir Ahmed David Ventola Claus Daniel 《Drying Technology》2018,36(2):234-244
Processing lithium-ion battery (LIB) electrode dispersions with water as the solvent during primary drying offers many advantages over N-methylpyrrolidone (NMP). An in-depth analysis of the comparative drying costs of LIB electrodes is discussed for both NMP- and water-based dispersion processing in terms of battery pack $/kWh. Electrode coating manufacturing and capital equipment cost savings are compared for water vs. conventional NMP organic solvent processing. A major finding of this work is that the total electrode manufacturing costs, whether water- or NMP-based, contribute about 8–9% of the total pack cost. However, it was found that up to a 2?×?reduction in electrode processing (drying and solvent recovery) cost can be expected along with a $3–6?M savings in associated plant capital equipment (for a plant producing 100,000 10-kWh Plug-in Hybrid Electric Vehicle (PHEV) batteries) using water as the electrode solvent. This paper shows a different perspective in that the most important benefits of aqueous electrode processing actually revolve around capital equipment savings and environmental stewardship and not processing cost savings. 相似文献
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OL Lopez RP Brenner JT Becker RF Ulrich F Boller ST DeKosky 《Canadian Metallurgical Quarterly》1997,48(6):1521-1525
We examined whether either psychotic features (e.g., delusions and hallucinations) or EEG abnormalities are associated with more rapid progression of Alzheimer's disease (AD). AD patients with psychosis have exhibited more EEG abnormalities than those without psychosis, and both abnormal EEG and psychosis have been noted to be predictors of functional and cognitive decline in AD. Ninety-five probable AD patients participating in a longitudinal study of dementia had an EEG and a semistructured psychiatric interview at baseline. Using EEG spectral analysis, we classified records as normal/abnormal based on the parasagittal mean frequency. Patients with abnormal EEGs were more functionally (e.g., Blessed Rating Scale for activities of daily living) and cognitively (e.g., Mini-Mental State) impaired than patients with normal EEG. AD patients with psychosis were only more functionally impaired than patients without psychosis. A two-factor analysis showed no interaction between abnormal EEG and psychosis. In addition, using a Cox proportional hazard model adjusted for age and education, the presence of an abnormal EEG or psychotic symptom at study entry was associated with higher risk of reaching severe cognitive and functional impairment during follow-up. Neither abnormal EEG nor the presence of psychosis predicted death. These results indicate that both abnormal EEG and psychosis are independent predictors of disease progression but not of physical survival. 相似文献
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BACKGROUND: Since its foundation in 1960, the International Society of Nephrology (ISN) has pursued the worldwide advancement of education, science and patient care in nephrology. This goal was achieved by means of the Society's journal and the organization of international congresses and symposia. In order to better reach its colleagues and patients in economically less developed countries, the ISN expanded its activities as of 1980 by a large number of specific programs aimed at these regions. METHODS: The first phase of activities included teaching programs, fellowship and visiting scholar programs, and the provision of travel grants to enhance accessibility to the ISN congresses. A second phase consisted of the creation of a library enhancement program, a commission on acute renal failure and--to improve the organization and efficiency--a central commission on global advancement of nephrology (COMGAN). Currently, a third phase has been entered in which all activities have been intensified: (1) under the guidance of COMGAN, supported by a large number of teaching programs and fact finding missions; (2) by establishing a renal sister program; and (3) by initiating commissions on informatics and on clinical trials. RESULTS: As a result, the ISN has reached most parts of the world, previously deprived of contact with renal science and renal patient care. The fellowship program now counts 160 fellows, who spend one or two years in training. The library enhancement program reaches 218 institutions worldwide. ISN membership has soared over the past two years with over 2,500 new members, mostly in the developing countries. They receive Kidney International and other relevant forms of information. Thus far, 135 pairs of renal units in developing and developed countries have been linked for support on a more continuous basis. ISN-sponsored congresses, symposia, and courses are being held in increasing numbers in the developing world. In many of its activities, the ISN closely collaborates with sister organizations, which also contribute financially. In total, the ISN spends annually over $1 million US from its own budget on the programs described above. CONCLUSION: The various programs and initiatives are proving helpful in advancing renal medicine in areas in need. Expansion into supporting similar programs within other medical subspecialties is being explored. 相似文献
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Claus Bahlmann Author Vitae 《Pattern recognition》2006,39(1):115-125
The selection of valuable features is crucial in pattern recognition. In this paper we deal with the issue that part of features originate from directional instead of common linear data. Both for directional and linear data a theory for a statistical modeling exists. However, none of these theories gives an integrated solution to problems, where linear and directional variables are to be combined in a single, multivariate probability density function. We describe a general approach for a unified statistical modeling, given the constraint that variances of the circular variables are small. The method is practically evaluated in the context of our online handwriting recognition system frog on hand and the so-called tangent slope angle feature. Recognition results are compared with two alternative modeling approaches. The proposed solution gives significant improvements in recognition accuracy, computational speed and memory requirements. 相似文献
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RM Bionta G Blewitt CB Bratton D Casper A Ciocio R Claus M Crouch ST Dye S Errede GW Foster W Gajewski KS Ganezer M Goldhaber TJ Haines TW Jones D Kielczewska WR Kropp JG Learned JM LoSecco J Matthews HS Park LR Price F Reines J Schulz S Seidel E Shumard D Sinclair HW Sobel JL Stone L Sulak R Svoboda G Thornton van der Velde JC C Wuest 《Canadian Metallurgical Quarterly》1987,36(1):30-36
10.
Dr. Jana Buchwalter Prof. Dr. Walter Brenner Dr. Rüdiger Zarnekow 《WIRTSCHAFTSINFORMATIK》2002,44(4):345-353
Many companies and purchasing departments only possess a limited knowledge about the modelling of inter-company business processes for electronic procurement. In the past the discussion about electronic procurement was mostly focused on technical aspects. This article introduces a reference process model for procurement auctions. The process model is made up of a basic process, which describes a minimal process for procurement auctions, and a number of process alternatives, which allow for the adoption of the basic process to changing parameters and individual company requirements. 相似文献