998 research outputs found
Estimating the Division Kernel of a Size-Structured Population
We consider a size-structured population describing the cell divisions. The
cell population is described by an empirical measure and we observe the
divisions in the continuous time interval [0, T ]. We address here the problem
of estimating the division kernel h (or fragmentation kernel) in case of
complete data. An adaptive estimator of h is constructed based on a kernel
function K with a fully data-driven bandwidth selection method. We obtain an
oracle inequality and an exponential convergence rate, for which optimality is
considered
Peran Diplomasi Budaya Dalam Mewujudkan Komunitas Sosial-budaya ASEAN: Kasus Vietnam
In the era of globalization and International integration, International relationships is an integral part in foreign policy. So that the foreign policy conducted well, all countries must implement diplomacy. Cultural diplomacy is not only the application, the empowering culture to improve the behavior of diplomacy, but also the diplomacy using to respect and preserve the culture. The reality and the implementation of the Vietnam government and Party in recent years will mostly contribute to answer it. From here, the importance of cultural diplomacy in the process of establishing ASEAN Community 2015 will be seen as well. Cultural diplomacy not only improves the position and the authority of Vietnam in the International arena, but also strengthens the relations with other countries and contributes to the formation of ASEAN Social-Cultural Community in particularly and ASEAN Community 2015 in general
Automatic Crack Detection in Built Infrastructure Using Unmanned Aerial Vehicles
This paper addresses the problem of crack detection which is essential for
health monitoring of built infrastructure. Our approach includes two stages,
data collection using unmanned aerial vehicles (UAVs) and crack detection using
histogram analysis. For the data collection, a 3D model of the structure is
first created by using laser scanners. Based on the model, geometric properties
are extracted to generate way points necessary for navigating the UAV to take
images of the structure. Then, our next step is to stick together those
obtained images from the overlapped field of view. The resulting image is then
clustered by histogram analysis and peak detection. Potential cracks are
finally identified by using locally adaptive thresholds. The whole process is
automatically carried out so that the inspection time is significantly improved
while safety hazards can be minimised. A prototypical system has been developed
for evaluation and experimental results are included.Comment: In proceeding of The 34th International Symposium on Automation and
Robotics in Construction (ISARC), pp. 823-829, Taipei, Taiwan, 201
Adaptive nonparametric estimation of a component density in a two-class mixture model
A two-class mixture model, where the density of one of the components is
known, is considered. We address the issue of the nonparametric adaptive
estimation of the unknown probability density of the second component. We
propose a randomly weighted kernel estimator with a fully data-driven bandwidth
selection method, in the spirit of the Goldenshluger and Lepski method. An
oracle-type inequality for the pointwise quadratic risk is derived as well as
convergence rates over Holder smoothness classes. The theoretical results are
illustrated by numerical simulations
Multi-Objective Optimization for IRS-Aidded Multi-user MIMO SWIPT Systems
In this paper, we investigate an intelligent reflecting surface (IRS) assisted simultaneous wireless information and power transfer (SWIPT) system in which users equipped with multiple antennas exploit power-splitting (PS) strategies for simultaneously information decoding (ID) and energy harvesting (EH). Different from the majority of previous studies which focused on single objective optimization problems (SOOPs) and assumed the linearity of EH models, in this paper, we aim at studying the multi-objective optimization problem (MOOP) of the sum rate (SR) and the totalharvested energy (HE) subject to the maximum transmit power (TP) constraint, the user quality of service (QoS), and HE requirements at each user with taking a practical non-linear EH (NLEH) model into consideration. To investigate insightful tradeoffs between the achievable SR and total HE, we adopt the modified weighted Tchebycheff method to transform the MOOP into a SOOP. However, solving the SOOPs and modified SOOP is mathematically difficult due to the non-convexity of the object functions and the constraints of the coupled variables of the base station (BS) transmit precoding matrices (TPMs), the user PS ratios (PSRs), and the IRS phase shift matrix (PSM). To address these challenges, an alternating optimization (AO) framework is used to decompose the formulated design problem into sub-problems. In addition, we apply the majorization-minimization (MM) approach to transform the sub-problems into convex optimization ones. Finally, numerical simulation results are conducted to verify the tradeoffs between the SR and the total amount of HE. The numerical results also indicate that the considered system using the IRS with optimal phase shifts provides considerable performance improvement in terms of the achievable SR and HE as compared to the counterparts without using the IRS or with the IRS of fixed phase shifts
Nonparametric estimation of the fragmentation kernel based on a PDE stationary distribution approximation
We consider a stochastic individual-based model in continuous time to
describe a size-structured population for cell divisions. This model is
motivated by the detection of cellular aging in biology. We address here the
problem of nonparametric estimation of the kernel ruling the divisions based on
the eigenvalue problem related to the asymptotic behavior in large population.
This inverse problem involves a multiplicative deconvolution operator. Using
Fourier technics we derive a nonparametric estimator whose consistency is
studied. The main difficulty comes from the non-standard equations connecting
the Fourier transforms of the kernel and the parameters of the model. A
numerical study is carried out and we pay special attention to the derivation
of bandwidths by using resampling
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