831 research outputs found
Commuting Mode Choice Behaviour Study and Policy Suggestions for Low-Carbon Emission Transportation in Xi’an (China)
This study established the commuting mode choice models in the typical Chinese city of Xi’an by using the Logistic regression method. Results show that commuters will transfer from the walking, bicycle, electric-bicycle/motor or bus to the car if the commuting distance, household income or the car availability increase; commuters will transfer from the walking, bicycle, electric-bicycle/motor to the car and transit if the commuting distance increases; compared with transit, the shorter driving time is the significant factor for the commuters choosing cars. The findings indicate that there is the necessity of great investment in the public transit with high-quality services to shorten the traveling time, combined with measures of car restriction, parking control, road congestion charging and transit priority lanes for the low-carbon emission transportation development in Chinese cities. The findings in the typical city of Xi’an will provide reference value for other cities in the world
Localizing by Describing: Attribute-Guided Attention Localization for Fine-Grained Recognition
A key challenge in fine-grained recognition is how to find and represent
discriminative local regions. Recent attention models are capable of learning
discriminative region localizers only from category labels with reinforcement
learning. However, not utilizing any explicit part information, they are not
able to accurately find multiple distinctive regions. In this work, we
introduce an attribute-guided attention localization scheme where the local
region localizers are learned under the guidance of part attribute
descriptions. By designing a novel reward strategy, we are able to learn to
locate regions that are spatially and semantically distinctive with
reinforcement learning algorithm. The attribute labeling requirement of the
scheme is more amenable than the accurate part location annotation required by
traditional part-based fine-grained recognition methods. Experimental results
on the CUB-200-2011 dataset demonstrate the superiority of the proposed scheme
on both fine-grained recognition and attribute recognition
A Comparative Study on the Theories of Highway Planning
On the con text of traffic planning development and its application, the author analyses the theories of highway network planning and its practicalities in China. The highway network planning to conduct a comprehensive comparison of the two schools, points out the characteristics of each theory, the operation characteristics of adaptability and cost planning of regional circumstances in different sizes for easy selection of applications in the future depending on the purpose and conditions of the plan
End-to-End Differentiable Molecular Mechanics Force Field Construction
Molecular mechanics (MM) potentials have long been a workhorse of
computational chemistry. Leveraging accuracy and speed, these functional forms
find use in a wide variety of applications from rapid virtual screening to
detailed free energy calculations. Traditionally, MM potentials have relied on
human-curated, inflexible, and poorly extensible discrete chemical perception
rules (atom types) for applying parameters to molecules or biopolymers, making
them difficult to optimize to fit quantum chemical or physical property data.
Here, we propose an alternative approach that uses graph nets to perceive
chemical environments, producing continuous atom embeddings from which valence
and nonbonded parameters can be predicted using a feed-forward neural network.
Since all stages are built using smooth functions, the entire process of
chemical perception and parameter assignment is differentiable end-to-end with
respect to model parameters, allowing new force fields to be easily
constructed, extended, and applied to arbitrary molecules. We show that this
approach has the capacity to reproduce legacy atom types and can be fit to MM
and QM energies and forces, among other targets
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