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151.
Amorphous lithium electrolyte thin films, xLi2O·ySiO2·zP2O5, were deposited by rf magnetron sputtering of pure and mixed-phase lithium silicate, lithium phosphate, SiO2, Li2O, and Li2CO3 targets, and their compositions were determined using proton-induced y -ray emission spectroscopy, energy-dispersive X-ray analysis, Rutherford backscattering spectrometry, and atomic-emission spectroscopy. The deposition conditions were chosen to assure thermalization of the sputtered flux, which proved to be necessary in order to obtain a homogeneous distribution of Si and P in the films. Optical absorption and ac impedance measurements showed that glass-in-glass phase separation occurred in a large SiO2-rich domain of the composition diagram. In contrast to bulk glasses, all of the Li2O–SiO2 films were phase-separated, including those with lithia contents larger than lithium disilicate. High-performance liquid chromatography measurements revealed that, analogous to bulk glasses, the addition of SiO2 to Li2O-P2O5 compositions reduced the number of phosphate anion dimers, trimers, and higher anion polymers in the films through the formation of -Si-O-P-bonds. However, in contrast to bulk glasses, the distribution of phosphate anion polymers followed closely the Flory distribution, with the fraction of anion polymers decreasing monotonically with increasing chain length.  相似文献   
152.
We prove consistency results for two types of density estimators on a closed, connected Riemannian manifold under suitable regularity conditions. The convergence rates are consistent with those in Euclidean space as well as those obtained for a previously proposed class of kernel density estimators on closed Riemannian manifolds. The first estimator is the uniform mixture of heat kernels centered at each observation, a natural extension of the usual Gaussian estimator to Riemannian manifolds. The second is an approximate heat kernel (AHK) estimator that is motivated by more practical considerations, where observations occur on a manifold isometrically embedded in Euclidean space whose structure or heat kernel may not be completely known. We also provide some numerical evidence that the predicted convergence rate is attained for the AHK estimator.  相似文献   
153.
In this paper we examine, for the first time, the potential of remote sensing to monitor flood dynamics in urban areas and constrain mathematical models of these processes. This is achieved through the development of a unique data set consisting of a series of eight space-borne synthetic aperture radar (SAR) and aerial photographic images of flooding of the UK town of Tewkesbury acquired over an eight day period in summer 2007. Previous observations of urban flooding have used single image and wrack mark data and have therefore been unable to adequately chart the propagation and recession of flood waves through complex urban topography. By using a combination of space-borne radar and aerial imagery we are able to show that remotely sensed imagery, particularly from the new TerraSAR-X radar, can reproduce dynamics adequately and support flood modelling in urban areas. We illustrate that image data from different remote sensing platforms reveal sufficient information to distinguish between models with varying degrees of channel-floodplain connectivity, particularly toward the end of the recession phase of the event. For this test case, our results also show that high resolution SAR imagery even when acquired from satellites can reveal important hydraulic characteristics difficult to simulate with current dynamic flood models. Hence, it is established, at least for this test case and event, that SAR imagery from as far as several hundred kilometers from the Earth's surface can deliver important information about floodplain dynamics that can be used to identify and help build suitable models, even in built-up environments.  相似文献   
154.
The U.S. Department of Defense is in the process of assessing and remediating closed, transferred, and transferring military training ranges across the United States. Many of these sites have areas that are known to contain unexploded ordnance (UXO). Other sites or portions of sites are not expected to contain UXO, but some verification of this expectation using geophysical surveys is needed. Many sites are so large that it is often impractical and/or cost prohibitive to perform surveys over 100% of the site. In such cases, it is particularly important to be explicit about the performance required of the surveys. This article presents the statistical algorithms developed to support the design of geophysical surveys along transects (swaths) to find target areas (TAs) of anomalous geophysical readings that may indicate the presence of UXO. The algorithms described here determine (1) the spacing between transects that should be used for the surveys to achieve a specified probability of traversing the TA, (2) the probability of both traversing and detecting a TA of anomalous geophysical readings when the spatial density of anomalies within the TA is either uniform (unchanging over space) or has a bivariate normal distribution, and (3) the probability that a TA exists when it was not found by surveying along transects. These algorithms have been implemented in the Visual Sample Plan (VSP) software to develop cost-effective transect survey designs that meet performance objectives.  相似文献   
155.
The heavy civil engineering industry (railways, sewage-treatment, chemical and pharmaceutical facilities, oil and gas facilities, etc.) is one of the major contributors to the British economy and generally involves a high level of investment. Clients in this industry are demanding accurate cost estimates, proper analysis of out-turn cost and cost escalation, and a high quality risk analysis throughout the construction processes. Current practices in the industry have suggested that there is a lack of structured methodologies and systematic cost escalation approaches to achieve an appropriate cost analysis at the outset of projects and throughout the construction processes. In this context the prime objective of this research work is to develop a structured cost escalation methodology for improving estimating management and control in the heavy engineering industry construction processes. The methodology is composed of a forecasting model to predict cost indices of major items in industry and a risk knowledge-base model for identifying and quantifying causes of cost escalations. This paper reviews and discusses a knowledge-based model for applying a cost escalation factor. The cost escalation factor is made up of market variation, a risk element, and a component for bias. A knowledge elicitation strategy was employed to obtain the required knowledge for the model. The strategy included questionnaires, interviews, and workshops, and deliverables came in the form of influences and their effect on project cost escalation. From these deliverables, a decision support system and specifications for applying cost escalation to base estimates are presented.  相似文献   
156.
157.
As minority‐owned firms have penetrated the broader national marketplace—selling goods and services to corporate as well as government clients—the issue of capacity has surfaced. Particularly in government markets, one claim is that minority business enterprises (MBEs) are smaller, younger firms than nonminorities, and hence they often lack the capacity to compete effectively for government contracts. Affirmative action procurement programs, in this view, provide preferential treatment for less qualified businesses, generating reverse discrimination against the dominant, typically white‐male group of business owners. A counterclaim, put forth by proponents of preferential procurement programs, is that discriminatory barriers such as entrenched old‐boy networks impede MBE expansion into mainstream markets. Do the entrenched networks really thwart MBEs, or do they simply lack the capacity to compete? Empirical findings of this study support the discriminatory barrier explanation.  相似文献   
158.
159.
Working with suicidal inmates is among the most demanding elements of clinical practice in corrections, yet few studies regarding the characteristics of prison inmate suicide attempters or their attempts exist. This represents a significant gap as the method of attempt, the prison context, and the resulting lethality of these incidents may be different from attempts made outside of prison. This exploratory study is the first to apply a continuous scale rating of suicide attempt lethality to incidents where an inmate survived a suicide attempt. It describes the attempt incident dynamics and resulting range of lethality scores found within the study sample. It also examines the inmate adjustment and mental health characteristics that were associated with the lethality rating. Preliminary findings suggest that increases in suicide attempt lethality are associated with the presence of Axis II disorders, favorable staff interactions, and the decreased use of drugs other than marijuana, alcohol, cocaine, or depressants. A call for research to extend this exploration through replication is made and recommendations for clinical practice are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
160.
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