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151.
Payback is often used as a measure of profitability by prospective PV owners. Contrasting this measure with another financial gauge––life-cycle cash flow––the paper discusses why payback may not be the most appropriate measure for residential PV applications and why it may hide sound financial opportunities for those deciding to invest in a PV system.In parallel, the paper addresses another aspect of economic feasibility: the value of energy produced. For residential applications, this value is currently set at residential net-metered retail rates. We present preliminary evidence that a higher value, reflective of the local effective capacity of PV ought to be claimed for residential PV applications. 相似文献
152.
Shyla Joseph James T. Joseph Annamma John J. K. Thomas Sam Solomon 《Journal of Materials Science: Materials in Electronics》2011,22(7):741-744
LnTiSbxNb1−xO6 (Ln = Ce, Pr) ceramics were prepared by the conventional solid state ceramic route for x = 0, 0.05, 0.1, 0.15, 0.2 and 0.25.
The structure of the materials was analyzed using X-ray diffraction techniques. The cell parameters and the theoretical densities
of the samples were calculated using least square methods. The samples are sintered to more than 90% of the theoretical density
at 1,325–1,350 °C. The microwave dielectric properties were measured using the cavity resonator method. The surface morphology
of the sintered sample was analyzed using Scanning Electron Microscopy. All the materials have good microwave dielectric properties
and are suitable for dielectric resonator applications. 相似文献
153.
Tiesong Zhao Hanli Wang Sam Kwong C.-C. Jay Kuo Wolfgang A. Halang 《Journal of Visual Communication and Image Representation》2011,22(7):627-633
To enable robust video transmission over heterogeneous networks, the hierarchical B-picture prediction structure is employed in the state-of-the-art video coding standard H.264/SVC, aiming to produce scalable bitstreams with various frame rates. However, the exhaustive mode decision process with the hierarchical B-picture structure increases the computational complexity of H.264/SVC encoding dramatically. In this paper, a fast mode decision algorithm is proposed to speed up H.264/SVC encoding with the hierarchical B-picture structure, which is achieved by utilizing macroblock (MB) features, correlation of temporal–spatial neighboring MBs, and the discrepant characteristics of hierarchical layers. Extensive experimental results demonstrate that the proposed algorithm is able to reduce the encoding time of H.264/SVC significantly for video sequences with a wide range of resolutions, and meanwhile the video quality and compression ratio are well preserved. 相似文献
154.
Sam Oberter 《中国建筑装饰装修》2011,(5):138-143
更像工业设计师而非建筑师,建筑师将住宅设计浓缩到其空间特征——形成了一个墙面少、有一间浴室、布局开放的简洁盒子。该住宅是可持续的典范,同时是一种经济型的住宅选择。 相似文献
155.
Do‐Yeon Kim Suman Sinha‐Ray Jung‐Jae Park Jong‐Gun Lee You‐Hong Cha Sang‐Hoon Bae Jong‐Hyun Ahn Yong Chae Jung Soo Min Kim Alexander L. Yarin Sam S. Yoon 《Advanced functional materials》2014,24(31):4986-4995
The industrial scale application of graphene and other functional materials in the field of electronics has been limited by inherent defects, and the lack of simple deposition methods. A simple spray deposition method is developed that uses a supersonic air jet for a commercially available reduced graphene oxide (r‐GO) suspension. The r‐GO flakes are used as received, which are pre‐annealed and pre‐hydrazine‐treated, and do not undergo any post‐treatment. A part of the considerable kinetic energy of the r‐GO flakes entrained by the supersonic jet is used in stretching the flakes upon impact with the substrate. The resulting “frozen elastic strains” heal the defects (topological defects, namely Stone‐Wales defect and C2 vacancies) in the r‐GO flakes, which is reflected in the reduced ratio of the intensities of the D and G bands in the deposited film. The defects can also be regenerated by annealing. 相似文献
156.
Based on a time continuity condition proposed in our earlier work, we develop a fairly general framework, free of regularization issues, for producing initially rigid cohesive finite element models that are temporally convergent in an explicit dynamics setting. These models are adaptive in the sense that an interface is inactive until the traction across it reaches a critical level. We require that the traction across the interface be a continuous function of displacement, and therefore of time, i.e., the traction before and after activation should be the same. We demonstrate with examples that failure to satisfy this condition leads to non-optimal convergence or failure of convergence as the time step tends to zero. We also investigate the predicted crack path produced by a time continuous model versus a discontinuous model in a simulation of a laboratory experiment. The time-continuous model produces crack paths that are stable with variations of the time step and are close to laboratory measurements. 相似文献
157.
Shubhra Chandra Sam Gioskos Bruce D. James Barry J. Macauley Robert J. Magee 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1993,56(1):41-44
The results are reported for an investigation into the fungicidal properties of six triphenyltin(IV) compounds representing metal coordination numbers of four through six. These experiments were conducted against a number of soil and plant pathogenic fungi and compared with the results obtained from triphenyltin chloride. While all the compounds examined proved to be effective fungicides, differences at the concentration levels tested were not sufficiently pronounced to relate the degree of toxicity to the molecular structure. 相似文献
158.
RA Adegbola AG Falade BE Sam M Aidoo I Baldeh D Hazlett H Whittle BM Greenwood EK Mulholland 《Canadian Metallurgical Quarterly》1994,13(11):975-982
During a 2-year period 159 malnourished children ages 3 months to 5 years with radiologic evidence of pneumonia were investigated to determine the cause of their pneumonia. In addition 119 malnourished children without pneumonia, 119 well-nourished children with pneumonia and 52 well-nourished children without pneumonia were studied as controls. Percutaneous lung aspiration was performed on 35 malnourished and 59 well-nourished children with pneumonia. Bacteria were isolated from the blood, lung or pleural fluid of 28 (18%) malnourished children with pneumonia, 42 (35%) well-nourished children with pneumonia and from the blood of 5 (4%) malnourished children without pneumonia. Streptococcus pneumoniae and Haemophilus influenzae, which were the two organisms isolated most frequently in both groups of children with pneumonia, were found in 17 (11%) malnourished and 39 (33%) well-nourished children with pneumonia. Mycobacterium tuberculosis was detected in 5 malnourished children with pneumonia. A potentially pathogenic virus was identified in 35% of malnourished children with pneumonia and 40% of well-nourished children with pneumonia, and from 25% of children without pneumonia. The viruses identified most frequently were adenovirus and respiratory syncytial virus.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
159.
In this letter, we propose a macromodeling approach for the nitride-based trapping storage Flash EEPROM cell with intriguing 2nd-bit effect. Both unusual I/sub D/-V/sub D/ and I/sub D/-V/sub G/ characteristics of this 2-bit Flash cell can be accurately modeled by the macromodel. It also provides insights into the special device characteristics of the programmed cell. Furthermore, we can use this model to correctly evaluate the read speed degradation resulting from 2nd-bit effect. 相似文献
160.
Traditionally, metaphors such as "my job is a jail" have been treated as implicit similes (i.e., this metaphor would be treated as if it were a comparison statement, "my job is like a jail"). A. Tversky's (1977) account of similarity is applied to such nonliteral similarity expressions, and is shown to apply as readily to nonliteral comparisons as to literal comparisons. But treating metaphors as comparison statements fails to account for certain important phenomena, including metaphoricity itself (the judgment that a comparison statement is nonliteral). We argue that metaphors are exactly what they appear to be: class-inclusion assertions, in which the topic of the metaphor (e.g., "my job") is assigned to a diagnostic category (e.g., entities that confine one against one's will, are unpleasant, are difficult to escape from). In such assertions, the metaphor vehicle (e.g., "jail") refers to that category, and at the same time is a prototypical exemplar of that category. This account of metaphor provides a basis for a theory of metaphor comprehension, and also clarifies why people use metaphors instead of similes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献