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排序方式: 共有2916条查询结果,搜索用时 31 毫秒
941.
Erik Cambria Tim Benson Chris Eckl Amir Hussain 《Expert systems with applications》2012,39(12):10533-10543
Barriers to use health related quality of life measuring systems include the time needed to complete the forms and the need for staff to be trained to understand the results. An ideal system of health assessment needs to be clinically useful, timely, sensitive to change, culturally sensitive, low burden, low cost, involving for the patient and built into standard procedures. A new generation of short and easy-to-use tools to monitor patient outcomes on a regular basis has been recently proposed. These tools are quick, effective and easy to understand, as they are very structured and rigid. Such structuredness, however, leaves no space to those patients who would like to say something more. Patients, in fact, are usually willing to express their opinions and feelings in free text, rather than simply filling in a questionnaire, for either speaking out their satisfaction or for cathartic complaining. Sentic PROMs allow patients to evaluate their health status and experience in a semi-structured way and accordingly aggregate input data by means of sentic computing, while tracking patients’ physio-emotional sensitivity. 相似文献
942.
Realized volatility and the influence of market measures on predictability: Analysis of Nord Pool forward electricity data 总被引:1,自引:0,他引:1
Erik Haugom Sjur Westgaard Per Bjarte Solibakke Gudbrand Lien 《Energy Economics》2011,33(6):1206-1215
This is the first paper to utilize intra-daily high-frequency data and to apply known market measures for the prediction of volatility in the Nord Pool electricity forward market. The work is based on recent methods of separating realized volatility into two components: continuous and jump volatilities. In addition, the link between future price volatility and current observable economic variables is examined. The measures—trading volume, time-to-maturity, asymmetric effect from negative shocks, and intra-week seasonality—are assessed to identify improvements in day-ahead predictions. The model where the total variation is separated into its continuous and jump components is compared with the simpler heterogeneous autoregressive model of realized variation both in- and out-of-sample. The results show a strong degree of persistence in realized volatility, and significant impacts from the mentioned market measures when predicting Nord Pool forward price volatility. Hence, there is a clear preference for models accounting for the systematic impact of market measures to improve volatility assessment for tomorrow. Moreover, separating the total variation into continuous and jump components seems potentially useful when predicting day-ahead volatility. 相似文献
943.
Keister JW Smedley J Muller EM Bohon J Héroux A 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,649(1):91-93
High purity, single crystal CVD diamond plates are screened for quality and instrumented into a sensor assembly for quantitative characterization of flux and position sensitivity. Initial investigations have yielded encouraging results and have led to further development. Several limiting complications are observed and discussed, as well as mitigations thereof. For example, diamond quality requirements for x-ray diodes include low nitrogen impurity and crystallographic defectivity. Thin electrode windows and electronic readout performance are ultimately also critical to device performance. Promising features observed so far from prototype devices include calculable responsivity, flux linearity, position sensitivity and timing performance. Recent results from testing in high flux and high speed applications are described. 相似文献
944.
Klaus H. Ostenfeld Erik Y. Andersen 《Frontiers of Architecture and Civil Engineering in China》2011,5(4):479-495
Modern bridge building is much more than concrete, steel and money. The overall socioeconomic impact, influence on people
migration, traffic, use of primary materials, safety of construction impact on the environment, energy, risk scenarios, health,
and most relevant now: climate and CO2 emissions, are among the parameters which enter into the decision process at the overall holistic conceptual level, the more
detailed level of selection of bridge sites, and selection of bridge types as well as construction methods and selection of
materials and products. 相似文献
945.
Techno‐economic analysis of an integrated biorefinery system for poly‐generation of power,heat, pellet and bioethanol
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Bioethanol is an alternative to fossil fuels in the transportation sector. The use of pellet for heating is also an efficient way to mitigate greenhouse gas emissions. This paper evaluates the techno‐economic performance of a biorefinery system in which an existing combined heat and power (CHP) plant is integrated with the production of bioethanol and pellet using straw as feedstock. A two‐stage acid hydrolysis process is used for bioethanol production, and two different drying technologies are applied to dry hydrolysis solid residues. A sensitivity analysis is performed on critical parameters such as the bioethanol selling price and feedstock price. The bioethanol production cost is also calculated for two cases with either 10 year or 15 year payback times. The results show that the second case is currently a more feasible economic configuration and reduces production costs by 36.4%–77.3% compared to other types of poly‐generation plants that are not integrated into existing CHP plants. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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948.
Julian Long Daniel Ross Erik Tastepe Mikayla Lamb Yusuke Funamoto Daichi Shima Tomosumi Kamimura Hitomi Yamaguchi 《Journal of the American Ceramic Society》2020,103(5):3008-3019
Fused silica optics used in lasing systems requires a high laser-induced damage resistance. Processes typically used to polish fused silica lenses induce subsurface and surface damage that collect ceria abrasive, creating a layer of contamination. The contamination can be a precursor to laser damage during use. A preliminary study showed the feasibility of magnetic field-assisted finishing (MAF) for polishing fused silica and suggested possible beneficial effects of the MAF-polished surface on the laser-induced damage threshold (LIDT). This paper proposes a method to examine the fundamental polishing characteristics of MAF for fused silica. Using the proposed method, this paper explores the material removal characteristics of the MAF process and improves the understanding of the MAF polishing mechanism. The 45% improvement of LIDT shows the efficacy of MAF for removing the contamination layer of fused silica surfaces with minimal changes in the surface roughness. 相似文献
949.
Surface texturing of silicon substrates with nanowells can change the lubricious performance of cationic polymer lubricant
(CPL), a bound-and-mobile lubricant consisting of a polydimethylsiloxane (PDMS) backbone with covalently bonded quaternary
ammonium iodide cations. The filled nanowell reservoirs enhance self-healing within the contact track since they can readily
provide CPL to near-by regions. However, once this initial reservoir is completely consumed and depleted, the empty nanowells
interfere with long-distance lateral flow process since they act as a reservoir that needs to be filled during the flow. 相似文献
950.
We report direct encapsulation of a sustainable solvent system in silica microcapsules via a sol-gel reaction of silica precursor for potential application of thermoplastic self healing polymeric system. The silica microcapsules were realized by hydrolysis and condensation of tetraethyl orthosilicate (TEOS) using aqueous glycerol microemulsion as template. The pre-hydrolysis of TEOS was found to be useful to obtain isolated free flowing silica microcapsules. Furthermore, the effects of different parameters viz. temperature, rotor speed, the solvent/TEOS ratio on the synthesis of silica microcapsules are studied. A novel micro compression technique to study mechanical properties of the silica microcapsules is reported. The silica microcapsules reported were found to have better mechanical properties compared to incumbent Urea-Formaldehyde (UF) based organic microcapsules. 相似文献