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101.
Rose Ann Fox 《Rocks & Minerals》2013,88(6):278-279
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Martin Oschatz Marcus Rose Nicole Klein Thomas Freudenberg Gleb Yushin 《Carbon》2010,48(14):3987-3992
A hierarchical and highly porous carbide-derived carbon (CDC) was obtained by nanocasting of pre-ceramic precursors into cubic ordered silica (KIT-6) and subsequent chlorination. Resulting CDC replica materials show high methane and n-butane uptake and excellent performance as electrode materials in supercapacitors. 相似文献
105.
A 1 wt% lysozyme solution was used as a model fluid to test a previously formulated mathematical model for the initial chemical reaction fouling rate of a heat transfer surface. The experimental results showed that, at a given wall temperature, a maximum initial fouling rate existed over a range of fluid velocities. The maximum rate and the fluid velocity at which it occurred both increased as the wall temperature increased. These observations were consistent with the model. Quantitatively, the average absolute percent deviation between the experimental results and the optimum model predictions was 23,3%. The decrease in initial fouling rate with increasing velocity at high fluid velocities was even greater than predicted by the model. 相似文献
106.
Sobo EJ Billman G Lim L Murdock JW Romero E Donoghue D Roberts W Kurtin PS 《The Joint Commission journal on quality improvement》2002,28(9):498-509
BACKGROUND: The Institute of Medicine's 2001 report on quality delimits six dimensions of optimal care: safety, effectiveness, efficiency, timeliness, patient centeredness, and equity. In fall 2001 parents of pediatric cancer patients were interviewed to determine how well they thought these dimensions were addressed with respect to medication administration. Immediate goals were to identify system weaknesses and devise strategies to prevent future errors. A higher-order goal was to develop and demonstrate a model protocol for rapid-cycle interview assessments. METHODS: Hematology/oncology directors worked with a research expert to develop a semistructured interview protocol. After training, which included directed reading, oral instruction, and role-playing, a convenience sample of 20 English- and Spanish-speaking parents of inpatients was recruited. Parents were asked to characterize current medication administration practices and to describe problems that they had experienced or witnessed. Rapid content analysis techniques were used to identify issues of importance to the parents. FINDINGS: Parents' medication concerns centered on their children's comfort. Parents called for communication improvements, standardization of all nursing procedures and techniques, and a guide or an outline providing a clear understanding of what to expect when and from whom. Viewing these concerns in relation to the Institute of Medicine's quality domains allowed the department to frame an improvement action plan aligned with organizational and national priorities. IMPLICATIONS: With good supervision and limited focused training, inexperienced staff can successfully administer semistructured qualitative interviews and help analyze findings for rapid cycle improvement purposes. The protocol can be adapted for use in organizations interested in rapid qualitative assessments of patient and parent preferences. 相似文献
107.
本研究的主要目标是在鼓励创造性思维的同时,建立一个结构化方法用于阐明产品生命周期策略。当前提倡采用适用于大多数产品的通用规则。联系“通用性”原则,与“放之四海皆准”的方法相比,本研究找出了影响产品生命终期的主要因素。研究结果可分为两个核心部分。第一,根据产品的技术特性,该方法论确定了合理的产品生命终期策略第二,为了评估和验证该方法,将产品生命终期策略的分类和当前工业实践进行了对比,开发的产品生命终期设计顾问(ELDA)软件,指导生产商确定适合的产品生命终期策略。对产品生命终期进行分类的能力使得设计者能够重新设计对环境负荷较小产品。这篇文章为设计者和生产管理者提供了合适的产品生命终期策略。通过更深入的理解相应产品的生命终期策略,本文的研究结果能够帮助设计者开发适合他们情况的、系统的产品生命终期策略。通过技术革新或者价值链的改进,将ELDA的结果运用于生命终期改善。 相似文献
108.
Nayak J. Tuncel E. Rose K. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2006,52(10):4626-4629
This correspondence presents a novel application of the theta function defined by Lovasz. The problem of coding for transmission of a source through a channel without error when the receiver has side information about the source is analyzed. Using properties of the Lovasz theta function, it is shown that separate source and channel coding is asymptotically suboptimal in general. By contrast, in the case of vanishingly small probability of error, separate source and channel coding is known to be asymptotically optimal. For the zero-error case, it is further shown that the joint coding gain can in fact be unbounded. Since separate coding simplifies code design and use, conditions on sources and channels for the optimality of separate coding are also derived 相似文献
109.
Effects of foam on ocean surface microwave emission inferred from radiometric observations of reproducible breaking waves 总被引:1,自引:0,他引:1
Padmanabhan S. Reising S.C. Asher W.E. Rose L.A. Gaiser P.W. 《Geoscience and Remote Sensing, IEEE Transactions on》2006,44(3):569-583
WindSat, the first satellite polarimetric microwave radiometer, and the NPOESS Conical Microwave Imager/Sounder both have as a key objective the retrieval of the ocean surface wind vector from radiometric brightness temperatures. Available observations and models to date show that the wind direction signal is only 1-3 K peak-to-peak at 19 and 37 GHz, much smaller than the wind speed signal. In order to obtain sufficient accuracy for reliable wind direction retrieval, uncertainties in geophysical modeling of the sea surface emission on the order of 0.2 K need to be removed. The surface roughness spectrum has been addressed by many studies, but the azimuthal signature of the microwave emission from breaking waves and foam has not been adequately addressed. Recently, a number of experiments have been conducted to quantify the increase in sea surface microwave emission due to foam. Measurements from the Floating Instrumentation Platform indicated that the increase in ocean surface emission due to breaking waves may depend on the incidence and azimuth angles of observation. The need to quantify this dependence motivated systematic measurement of the microwave emission from reproducible breaking waves as a function of incidence and azimuth angles. A number of empirical parameterizations of whitecap coverage with wind speed were used to estimate the increase in brightness temperatures measured by a satellite microwave radiometer due to wave breaking in the field of view. These results provide the first empirically based parameterization with wind speed of the effect of breaking waves and foam on satellite brightness temperatures at 10.8, 19, and 37 GHz. 相似文献
110.
Two main security threats exist for DNS in the context of query/response transactions. Attackers can spoof authoritative name servers responding to DNS queries and alter DNS responses in transit through man-in-the-middle attacks, and alter the DNS responses stored in caching name servers. The IETF has defined the digital signature-based DNSSEC for protecting DNS query/response transactions through a series of requests for comments. 相似文献