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1.
Co-browsing is an activity in which a group of users navigate their way through of a set of Web pages together for a shared purpose. Effective co-browsing among users with different device capabilities requires a shared understanding of those Web pages. This paper demonstrates the concept of shared viewpoints (SVPs), and personal viewpoints (PVPs), for co-browsing, before detailing a framework for implementing these concepts. Finally, the effectiveness of the framework is presented through a perceptual experiment.  相似文献   
2.
An efficient algorithm is presented for numerically evaluating a self-consistent field theoretic (SCFT) model of block copolymer structure. This algorithm is implemented on a distributed memory parallel cluster in order to solve the SCFT equations on large computational grids. Simulation results are presented for a two-component molten mixture of a symmetric ABA triblock copolymer with an A homopolymer. These results illustrate a case in which simulating a large system is required to resolve features with a wide range of length scales.  相似文献   
3.
Efficient identification of forest age is useful for forest management and ecological applications. Here we propose a user-assisted method for determining forest age using high spatial resolution remotely sensed imagery. This method requires individual trees to be extracted from imagery and represented as points. We use a local maximum filter to generate points that are converted to Voronoi polygons. Properties of the Voronoi polygons are correlated with forest age and used to aggregate points (trees) into areas (stands) based on three forest age classes. Accuracy of the aggregation ranges from approximately 68% to 78% and identification of the mature class is more consistent and accurate than the younger classes.  相似文献   
4.
The authors examined heterogeneity in symptom trajectories among youths following psychiatric crises as well as the psychosocial correlates and placement outcomes associated with identified trajectories. Using semiparametric mixture modeling with 156 youths approved for psychiatric hospitalization, the authors identified 5 trajectories based on symptoms over the 16 months following crisis: high improved, high unimproved, borderline improved, borderline unimproved, and subclinical. Membership in unimproved symptom groups was associated with less suicidality, younger age, more youth hopelessness, and more caregiver empowerment. Improved symptom group membership predicted long-term decreases in days in out-of-home placements. More important, and in contrast with general impressions from the existing literature, findings suggest that a substantive proportion of youths with serious emotional disturbance sustain high levels of symptomatology following intensive mental health services. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
The growth of the Internet and of various intranets has spawned a wealth of online services, most of which are implemented on local-area clusters using remote invocation (for example, remote procedure call/remote method invocation) among manually placed application components. Component placement can be a significant challenge for large-scale services, particularly when application resource needs are workload dependent. Automatic component placement has the potential to maximize overall system throughput. The key idea is to construct (offline) a mapping between input workload and individual-component resource consumption. Such mappings, called component profiles, then support high-performance placement. Preliminary results on an online auction benchmark based on J2EE (Java 2 Platform, Enterprise Edition) suggest that profile-driven tools can identify placements that achieve near-optimal overall throughput.  相似文献   
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Changes in clinical and laboratory measures of disease activity were studied prospectively in 12 European centers. Altogether 282 rheumatoid patients were evaluated during 6 months of therapy with slow-acting drugs. Patients' global assessment was taken to indicate overall response. The number of swollen joints and number of tender joints correlated highly with this. The erythrocyte sedimentation rate (ESR) correlated less well but was more uniform across centers. Grip strength, C-reactive protein and hemoglobin performed poorly between centers. There were cultural and linguistic difficulties using the Health Assessment Questionnaire in a European setting. Physician's global assessments were similar to the patient's global assessments and provided redundant information. The best measures are: the number of swollen joints, the number of tender joints, the ESR, and the patient's global assessment. It may also help to measure articular pain.  相似文献   
8.
The mechanical fracture strength and toughness of short-fibre composites, injection moulded from compounds of poly(ethylene terephthalate) (PET) containing 10 and 30% (by weight) (w/o) glass, have been investigated and the dependence upon matrix hydrolytic stability determined. Mouldings have been characterised by several physical techniques to evaluate molecular weight, degradation rates, crystallinity and morphology, whilst time-dependent gravimetric data were derived to quantify sorption kinetics and allow comparisons with theoretical reaction rates to be made. During melt processing, PET is hydrolysed extremely rapidly by traces of moisture (<0.02w/o). yet the inherent strength of moulded composites declines significantly only below an apparently critical molecular weight. However, on long-term humid ageing in hot water, impact behaviour especially is rendered more complex by simultaneous crystallisation, molecular reorder and losses of interfacial bond strength.  相似文献   
9.
The current, most frequently employed, commercial route to produce hydroxyapatite prosthetic coatings is plasma spraying. However, this has several important limitations especially for textured surfaces. Low temperature methods of coating fabrication such as cathodic electrodeposition are attractive alternatives. However, quantitative characterisation of the phase composition of thin electrodeposited coatings can be problematic. An X-ray diffraction method, which provides quantitative compositional information without reference to external or internal standards, is introduced and validated. The method can also be applied when Bragg peaks from the supporting substrate are apparent within the data and preferred orientation can be tolerated. This method has been used to examine in detail the microstructure of electrodeposited coatings which are compared directly with those formed by a commercial plasma spraying process.We show that, unlike the plasma sprayed coatings, the electrodeposited material consists of a single crystalline phase (hydroxyapatite) and a significantly reduced amorphous phase. The electrodeposited coatings also possess significantly more microstrain and a smaller crystallite size than the corresponding plasma sprayed material.  相似文献   
10.
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