82 research outputs found
A deformed Hermitian Yang-Mills Flow
We study a new deformed Hermitian Yang-Mills Flow in the supercritical case.
Under the same assumption on the subsolution as Collins-Jacob-Yau
\cite{cjy2020cjm}, we show the longtime existence and the solution converges to
a solution of the deformed Hermitian Yang-Mills equation which was solved by
Collins-Jacob-Yau \cite{cjy2020cjm} by the continuity method.Comment: This version is more readable and some references are adde
The Neumann problem of special Lagrangian type equations
We study the Neumann problem for special Lagrangian type equations with
critical and supercritical phases. These equations naturally generalize the
special Lagrangian equation and the k-Hessian equation. By establishing uniform
a priori estimates up to the second order, we obtain the existence result using
the continuity method. The new technical aspect is our direct proof of boundary
double normal derivative estimates. In particular, we directly prove the double
normal estimates for the 2-Hessian equation in dimension 3. Moreover, we solve
the classical Neumann problem by proving the uniform gradient estimate.Comment: 24 page
Evaluation of Pedestrian Level of Service at Signalised Intersections from the Elderly Perspective
The crossing decisions and behaviour of elderly pedestrians are affected by the pedestrian level of service (PLOS). In this paper, an evaluation model was established to analyse the relationship between the traffic environment and the perceived evaluation of elderly pedestrians. Firstly, the characteristic parameters of the selected intersections and the perceived evaluation data of elderly pedestrians at the synchronisation scenery were extracted using manual recording and questionnaire-based truncation methods. The correlation between the perceived evaluation data of elderly pedestrians and the traffic parameters were tested with respect to the dimensions of safety, convenience and efficiency. Then, the significant parameters affecting PLOS were recognised. Based on the traffic characteristic parameters, the PLOS evaluation model from the elderly perspective was established using the fuzzy linear regression method. PLOS classification thresholds were obtained using the fuzzy C-means clustering algorithm. The data from two intersections were used to validate the model. The results show that the difference between the actual and the predicted PLOS values of the two crosswalks were 0.2 and 0.1, respectively. Thus, the proposed PLOS evaluation model in this paper can be used to accurately predict the PLOS from the elderly perspective using the traffic data of signalised intersections
The parabolic quaternionic Monge-Amp\`{e}re type equation on hyperK\"{a}hler manifolds
We prove the long time existence and uniqueness of solution to a parabolic
quaternionic Monge-Amp\`{e}re type equation on a compact hyperK\"{a}hler
manifold. We also show that after normalization, the solution converges
smoothly to the unique solution of the Monge-Amp\`{e}re equation for
-quaternionic psh functions
The Monge-Amp\`{e}re equation for -quaternionic PSH functions on a hyperK\"{a}hler manifold
We prove the existence of unique smooth solutions to the quaternionic
Monge-Amp\`{e}re equation for -quaternionic plurisubharmonic functions
on a hyperK\"{a}hler manifold and thus obtain solutions for the quaternionic
form type equation. We derive estimate by establishing a Cherrier-type
inequality as in Tosatti and Weinkove [22]. By adopting the approach of Dinew
and Sroka [9] to our context, we obtain and estimates without
assuming the flatness of underlying hyperK\"{a}hler metric comparing to
previous results [14].Comment: 31 page
Targeted Activation Penalties Help CNNs Ignore Spurious Signals
Neural networks (NNs) can learn to rely on spurious signals in the training
data, leading to poor generalisation. Recent methods tackle this problem by
training NNs with additional ground-truth annotations of such signals. These
methods may, however, let spurious signals re-emerge in deep convolutional NNs
(CNNs). We propose Targeted Activation Penalty (TAP), a new method tackling the
same problem by penalising activations to control the re-emergence of spurious
signals in deep CNNs, while also lowering training times and memory usage. In
addition, ground-truth annotations can be expensive to obtain. We show that TAP
still works well with annotations generated by pre-trained models as effective
substitutes of ground-truth annotations. We demonstrate the power of TAP
against two state-of-the-art baselines on the MNIST benchmark and on two
clinical image datasets, using four different CNN architectures.Comment: 24 pages including appendix; extended version of a paper accepted to
AAAI-2024 under the same titl
The Dirichlet problem of the homogeneous -Hessian equation in a punctured domain
In this paper, we consider the Dirichlet problem for the homogeneous
-Hessian equation with prescribed asymptotic behavior at where
is a -convex bounded domain in the Euclidean space. The
prescribed asymptotic behavior at of the solution is zero if
, it is if and
if . To solve this problem, we
consider the Dirichlet problem of the approximating -Hessian equation in
with small. We firstly construct the
subsolution of the approximating -Hessian equation. Then we derive the
pointwise -estimates of the approximating equation based on new gradient
and second order estimates established previously by the second author and the
third author. In addition, we prove a uniform positive lower bound of the
gradient if the domain is starshaped with respect to . As an application, we
prove an identity along the level set of the approximating solution and obtain
a nearly monotonicity formula. In particular, we get a weighted geometric
inequality for smoothly and strictly -convex starshaped closed
hypersurface in with .Comment: 33 pages. arXiv admin note: text overlap with arXiv:2207.1350
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