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191.
Face recognition via adaptive image combination 总被引:1,自引:0,他引:1
于威威 《上海交通大学学报(英文版)》2010,15(5):600-603
Dimension reduction and manifold learning are the two most popular feature extraction methods. The two methods focus on spatial
locality as a guiding principle to find a low-dimensional basis for describing high-dimensional data, but no bases or features
are more spatially localized than the original image pixels. So, adaptive image combination is presented to represent a class
by a combined sample. The combined sample is a linear combination of original samples in the same class. Adaptive image combination
(AIC) find the best combination coefficients by minimizing the intrapersonal distance and maximizing the interpersonal distance.
Experimental results show that AIC is effective. 相似文献
192.
There is a growing literature that promotes the presence of a mix of compensatory and semi-compensatory processing strategies
in the way that individuals evaluate packages of attributes in real or hypothetical markets, and make choices. This paper
proposes a specification for the utility form in a choice model to test if, given a pair of attributes with a common-metric
(e.g., components of travel time or cost), the attribute with the dominating level defines the marginal (dis)utility that
is assigned to both attributes. We refer to this processing strategy as a parameter transfer rule. We use a stated choice
data set, in the context of car driving individuals choosing between tolled and non-tolled routes, to estimate a mixed logit
model which incorporates the presence of the parameter transfer rule and the conventional fully compensatory rule, both existing
up to a probability. We find that if this parameter transfer heuristic is part of the mix, the WTP is more than 30% higher,
on average, than when only a fully compensatory rule is imposed. We also contrast the parameter transfer rule with other semi-compensatory
heuristics which have been investigated in other papers, and show that the finding adds further support to the accumulating
evidence that a semi-compensatory attribute processing rules tend to result in higher mean WTP estimates compared to the fully
compensatory attribute processing rule. 相似文献
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198.
Runyu Wang 《WMU Journal of Maritime Affairs》2011,10(2):143-165
Since the 1980s, the precautionary principle has been drawing more and more international attention. This became particularly
clear during the series of Conferences on the Protection of the North Sea, which addressed marine environmental protection,
and initiated the application of the principle into maritime affairs. Although a unified concept of the precautionary principle
is lacking, some typical formulations have been concluded in regional treaties and international documents, and components
of the principle can be summarised (Part I and Part II). The precautionary principle has been adopted by international documents
involving different fields of law of the sea, and been addressed by international courts and tribunals (Part III). While the
precautionary principle is still not part of customary international law (Part IV), its increasing level of worldwide acceptance
suggests that it will become a customary international law in the future. 相似文献
199.
This paper documents the efforts to operationalize the conceptual framework of MIcrosimulation Learning-based Approach to
TRansit Assignment (MILATRAS) and its component models of departure time and path choices. It presents a large-scale real-world
application, namely the multi-modal transit network of Toronto which is operated by the Toronto Transit Commission (TTC).
This large-scale network is represented by over 500 branches with more than 10,000 stops. About 332,000 passenger-agents are
modelled to represent the demand for the TTC in the AM peak period. A learning-based departure time and path choice model
was adopted using the concept of mental models for the modelling of the transit assignment problem. The choice model parameters
were calibrated such that the entropy of the simulated route loads was optimized with reference to the observed route loads,
and validated with individual choices. A Parallel Genetic Algorithm engine was used for the parameter calibration process.
The modelled route loads, based on the calibrated parameters, greatly approximate the distribution underlying the observed
loads. 75% of the exact sequence of transfer point choices were correctly predicted by the off-stop/on-stop choice mechanism.
The model predictability of the exact sequence of route transfers was about 60%. In this application, transit passengers were
assumed to plan their transit trip based on their experience with the transportation network; with no prior (or perfect) knowledge
of service performance. 相似文献
200.
This paper establishes a link between an activity-based model for the Greater Toronto Area (GTA), dynamic traffic assignment,
emission modelling, and air quality simulation. This provides agent-based output that allows vehicle emissions to be tracked
back to individuals and households who are producing them. In addition, roadway emissions are dispersed and the resulting
ambient air concentrations are linked with individual time-activity patterns in order to assess population exposure to air
pollution. This framework is applied to evaluate the effects of a range of policy interventions and 2031 scenarios on the
generation of vehicle emissions and greenhouse gases in the GTA. Results show that the predicted increase of approximately
2.6 million people and 1.3 million jobs in the region by 2031 compared to 2001 levels poses a major challenge in achieving
meaningful reductions in GHGs and air pollution. 相似文献