This study presents an advanced method for post-mortem person identification using the segmentation of skeletal structures from chest X-ray images.The proposed approach employs the Attention U-Net architecture,enhance...This study presents an advanced method for post-mortem person identification using the segmentation of skeletal structures from chest X-ray images.The proposed approach employs the Attention U-Net architecture,enhanced with gated attention mechanisms,to refine segmentation by emphasizing spatially relevant anatomical features while suppressing irrelevant details.By isolating skeletal structures which remain stable over time compared to soft tissues,this method leverages bones as reliable biometric markers for identity verification.The model integrates custom-designed encoder and decoder blocks with attention gates,achieving high segmentation precision.To evaluate the impact of architectural choices,we conducted an ablation study comparing Attention U-Net with and without attentionmechanisms,alongside an analysis of data augmentation effects.Training and evaluation were performed on a curated chest X-ray dataset,with segmentation performance measured using Dice score,precision,and loss functions,achieving over 98% precision and 94% Dice score.The extracted bone structures were further processed to derive unique biometric patterns,enabling robust and privacy-preserving person identification.Our findings highlight the effectiveness of attentionmechanisms in improving segmentation accuracy and underscore the potential of chest bonebased biometrics in forensic and medical imaging.This work paves the way for integrating artificial intelligence into real-world forensic workflows,offering a non-invasive and reliable solution for post-mortem identification.展开更多
These days,social media has grown to be an integral part of people’s lives.However,it involves the possibility of exposure to“fake news”,which may contain information that is intentionally or inaccurately false to ...These days,social media has grown to be an integral part of people’s lives.However,it involves the possibility of exposure to“fake news”,which may contain information that is intentionally or inaccurately false to promote particular political or economic interests.The main objective of this work is to use the co-attention mechanism in a Combined Graph neural network model(CMCG)to capture the relationship between user profile features and user preferences in order to detect fake news and examine the influence of various social media features on fake news detection.The proposed approach includes three modules.The first one creates a Graph Neural Network(GNN)based model to learn user profile properties,while the second module encodes news content,user historical posts,and news sharing cascading on social media as user preferences GNN-based model.The inter-dependencies between user profiles and user preferences are handled through the third module using a co-attention mechanism for capturing the relationship between the two GNN-based models.We conducted several experiments on two commonly used fake news datasets,Politifact and Gossipcop,where our approach achieved 98.53%accuracy on the Gossipcop dataset and 96.77%accuracy on the Politifact dataset.These results illustrate the effectiveness of the CMCG approach for fake news detection,as it combines various information from different modalities to achieve relatively high performances.展开更多
This study presents a two-echelon inventory routing problem (2E-IRP) with an end-of-tour replenishment (ETR) policy whose distribution network consists of a supplier, several distribution centers (DCs) and several ret...This study presents a two-echelon inventory routing problem (2E-IRP) with an end-of-tour replenishment (ETR) policy whose distribution network consists of a supplier, several distribution centers (DCs) and several retailers on a multi-period planning horizon. A formulation of the problem based on vehicle indices is proposed in the form of a mixed integer linear program (MILP). The mathematical model of the problem is solved using a branch and cut (B&C) algorithm. The results of the tests are compared to the results of a branch and price (B&P) algorithm from the literature on 2E-IRP with a classical distribution policy. The results of the tests show that the B&C algorithm solves 197 out of 200 instances (98.5%). The comparison of the B&C and B&P results shows that 185 best solutions are obtained with the B&C algorithm on 197 instances (93.9%). Overall, the B&C algorithm achieves cost reductions ranging from 0.26% to 41.44% compared to the classic 2E-IRP results solved with the B&P algorithm, with an overall average reduction of 18.08%.展开更多
Pancreatic cancer is a highly lethal disease with a ge-netic susceptibility and familial aggregation found in 3%-16% of patients. Early diagnosis remains the only hope for curative treatment and improvement of prog-no...Pancreatic cancer is a highly lethal disease with a ge-netic susceptibility and familial aggregation found in 3%-16% of patients. Early diagnosis remains the only hope for curative treatment and improvement of prog-nosis. This can be reached by the implementation of an intensive screening program, actually recommended for individuals at high-risk for pancreatic cancer de-velopment. The aim of this strategy is to identify pre-malignant precursors or asymptomatic pancreatic can-cer lesions, curable by surgery. Endoscopic ultrasound (EUS) with or without fine needle aspiration(FNA) seems to be the most promising technique for early de-tection of pancreatic cancer. It has been described as a highly sensitive and accurate tool, especially for small and cystic lesions. Pancreatic intraepithelial neoplasia, a precursor lesion which is highly represented in high-risk individuals, seems to have characteristics chronic pancreatitis-like changes well detected by EUS. Many screening protocols have demonstrated high diagnostic yields for pancreatic pre-malignant lesions, allowing prophylactic pancreatectomies. However, it shows a high interobserver variety even among experienced en-dosonographers and a low sensitivity in case of chronic pancreatitis. Some new techniques such as contrast-en-hanced harmonic EUS, computer-aided diagnostic tech-niques, confocal laser endomicroscopy miniprobe andthe detection of DNA abnormalities or protein markersby FNA, promise improvement of the diagnostic yield ofEUS. As the resolution of imaging improves and as ourknowledge of precursor lesions grows, we believe thatEUS could become the most suitable method to detectcurable pancreatic neoplasms in correctly identifiedasymptomatic at-risk patients.展开更多
A new synchronization scheme for chaotic（hyperchaotic） maps with different dimensions is presented.Specifically,given a drive system map with dimension n and a response system with dimension m,the proposed approach ...A new synchronization scheme for chaotic（hyperchaotic） maps with different dimensions is presented.Specifically,given a drive system map with dimension n and a response system with dimension m,the proposed approach enables each drive system state to be synchronized with a linear response combination of the response system states.The method,based on the Lyapunov stability theory and the pole placement technique,presents some useful features：（i） it enables synchronization to be achieved for both cases of n 〈 m and n 〉 m;（ii） it is rigorous,being based on theorems;（iii） it can be readily applied to any chaotic（hyperchaotic） maps defined to date.Finally,the capability of the approach is illustrated by synchronization examples between the two-dimensional H′enon map（as the drive system） and the three-dimensional hyperchaotic Wang map（as the response system）,and the three-dimensional H′enon-like map（as the drive system） and the two-dimensional Lorenz discrete-time system（as the response system）.展开更多
In this paper, we construct a backward difference scheme for a class of SIR epidemic model with general incidence f . The step sizeτ used in our discretization is one. The dynamical properties are investigated (posit...In this paper, we construct a backward difference scheme for a class of SIR epidemic model with general incidence f . The step sizeτ used in our discretization is one. The dynamical properties are investigated (positivity and the boundedness of solution). By constructing the Lyapunov function, the general incidence function f must satisfy certain assumptions, under which, we establish the global stability of endemic equilibrium when R0 >1. The global stability of diseases-free equilibrium is also established when R0 ≤1. In addition we present numerical results of the continuous and discrete model of the different class according to the value of basic reproduction number R0.展开更多
This paper studies the dynamics of a new fractional-order discrete system based on the Caputo-like difference operator.This is the first study to explore a three-dimensional fractional-order discrete chaotic system wi...This paper studies the dynamics of a new fractional-order discrete system based on the Caputo-like difference operator.This is the first study to explore a three-dimensional fractional-order discrete chaotic system without equilibrium.Through phase portrait,bifurcation diagrams,and largest Lyapunov exponents,it is shown that the proposed fractional-order discrete system exhibits a range of different dynamical behaviors.Also,different tests are used to confirm the existence of chaos,such as 0-1 test and C0 complexity.In addition,the quantification of the level of chaos in the new fractional-order discrete system is measured by the approximate entropy technique.Furthermore,based on the fractional linearization method,a one-dimensional controller to stabilize the new system is proposed.Numerical results are presented to validate the findings of the paper.展开更多
The purpose of this paper is to extend the notion of regional controllability for hyperbolic parameter dependent systems.The key idea is the characterization of the averaged regional control with minimal energy.This c...The purpose of this paper is to extend the notion of regional controllability for hyperbolic parameter dependent systems.The key idea is the characterization of the averaged regional control with minimal energy.This control steers the state average(with respect to such a parameter)towards the desired state only on a given part of the system evolution domain.In this paper,we give the precis definition and the properties of this new concept.Then,we use an approach based on an extension of the Hilbert uniqueness method devoted to the calculation of the control in two different cases:zone control and pointwise control.展开更多
In this paper, we develop a mathematical model of the COVID-19 pandemic in Burkina Faso. We use real data from Burkina Faso National Health Commission against COVID-19 to predict the dynamic of the disease and also th...In this paper, we develop a mathematical model of the COVID-19 pandemic in Burkina Faso. We use real data from Burkina Faso National Health Commission against COVID-19 to predict the dynamic of the disease and also the cumulative number of reported cases. We use public policies in model in order to reduce the contact rate, this allows to show how the reduction of the daily report of infectious cases goes, so we would like to draw the attention of decision makers for a rapid treatment of reported cases.展开更多
We examined persistence in seven common preventive health practices for a nationally representative sample of Medicare beneficiaries over 4-year observation periods. Six panels from the 1997-2005 Medicare Current Bene...We examined persistence in seven common preventive health practices for a nationally representative sample of Medicare beneficiaries over 4-year observation periods. Six panels from the 1997-2005 Medicare Current Beneficiary Survey (MCBS) were used resulting in 13,913 unique individuals with ages ranging from below 65 (disabled) to over 80 years old. Persistence in behavior was defined as the proportion of the observation period beneficiaries participated in each activity. We estimated behavioral persistence as a function of baseline demographic, socioeconomic, and health characteristics using multivariate regression analysis. Beneficiaries were most persistent in smoking abstinence (81% reported not smoking) and least persistent with routine exercise (47% reporting none). From multivariate regression results, there was greater persistence among beneficiaries who were married when compared to those living alone (p 300% FPL compared to <100% FPL all p < 0.01). Increasing age (greater than 80 compared to 65 - 69) was associated with increased compliance in influenza vaccination and smoking cessation (p < 0.01) while negatively associated with weekly exercise and cancer screenings (p < 0.01). Medicare beneficiaries are inconsistently persistent with common preventive health practices.展开更多
In this paper, we study a class of Prigozhin equation for growing sandpile problem subject to local and a non-local boundary condition. The problem is a generalized model for a growing sandpile problem with Neumann bo...In this paper, we study a class of Prigozhin equation for growing sandpile problem subject to local and a non-local boundary condition. The problem is a generalized model for a growing sandpile problem with Neumann boundary condition (see <a href="#ref1">[1]</a>). By the semi-group theory, we prove the existence and uniqueness of the solution for the model and thanks to a duality method we do the numerical analysis of the problem. We finish our work by doing numerical simulations to validate our theoretical results.展开更多
In this paper, we study the impact of copying data in GPU computing. GPU computing allows implementing parallel computations at low cost: a GPU can be purchased at under USD 500. Many studies have shown that GPU can b...In this paper, we study the impact of copying data in GPU computing. GPU computing allows implementing parallel computations at low cost: a GPU can be purchased at under USD 500. Many studies have shown that GPU can be used to speed up the calculations. But for algorithms requiring doing a part of the calculations on GPU and another part on CPU, alternately, latency due to the copy of the data is a performance degradation factor. To illustrate this, we consider the Dijkstra’s algorithm on the shortest path used in solving optimization problems. This algorithm is very heavy to run on sequential machine. So, we are considering a parallel approach on GPU. Note that Dijkstra’s algorithm has been subject of many implementations on GPU. In the present work, we use two platforms with external GPU. Graphs are represented in adjacency matrix. During the computation of this algorithm, intermediates results are copied from GPU to CPU or from CPU to GPU. The purpose of this work is to measure the impact of these copies in the overall performance of the algorithm. For that we calculate time due to the copying data’s implementation;then we compare results with implementation computing only on CPU memory (zero-copy). The real impact shown by experiments demonstrates the interest of this study. GP-GPU programmers have to think that they will use either memory zero-copy or GPU memory. The challenge for GPU’s manufacturers is how to reduce this impact.展开更多
In this paper, we present parallel programming approaches to calculate the values of the cells in matrix’s scoring used in the Smith-Waterman’s algorithm for sequence alignment. This algorithm, well known in bioinfo...In this paper, we present parallel programming approaches to calculate the values of the cells in matrix’s scoring used in the Smith-Waterman’s algorithm for sequence alignment. This algorithm, well known in bioinformatics for its applications, is unfortunately time-consuming on a serial computer. We use formulation based on anti-diagonals structure of data. This representation focuses on parallelizable parts of the algorithm without changing the initial formulation of the algorithm. Approaching data in that way give us a formulation more flexible. To examine this approach, we encode it in OpenMP and Cuda C. The performance obtained shows the interest of our paper.展开更多
This article examines the architecture of software-defined networks (SDN) and its implications for the modern management of communications infrastructures. By decoupling the control plane from the data plane, SDN offe...This article examines the architecture of software-defined networks (SDN) and its implications for the modern management of communications infrastructures. By decoupling the control plane from the data plane, SDN offers increased flexibility and programmability, enabling rapid adaptation to changing user requirements. However, this new approach poses significant challenges in terms of security, fault tolerance, and interoperability. This paper highlights these challenges and explores current strategies to ensure the resilience and reliability of SDN networks in the face of threats and failures. In addition, we analyze the future outlook for SDN and the importance of integrating robust security solutions into these infrastructures.展开更多
This paper addresses the problem of identifying the unknown diffusion coefficient in a semilinear parabolic equation with incomplete initial condition.We propose an optimal control approach using the no-regret control...This paper addresses the problem of identifying the unknown diffusion coefficient in a semilinear parabolic equation with incomplete initial condition.We propose an optimal control approach using the no-regret control method and the adapted low-regret control.Our approach provides a fullcharacterisation of the unknown diffusion coefficient independent of the missing initial condition.We also present an optimality system that describes the adapted low-regret control and use it to find a fuil description of the no-regret control by taking the limit of the sequence of adapted low-regret controls.展开更多
This paper proposes three fractional discrete chaotic systems based on the Rulkov,Chang,and Zeraoulia–Sprott rational maps.The dynamics of the proposed maps are investigated by means of phase plots and bifurcations d...This paper proposes three fractional discrete chaotic systems based on the Rulkov,Chang,and Zeraoulia–Sprott rational maps.The dynamics of the proposed maps are investigated by means of phase plots and bifurcations diagrams.Adaptive stabilization schemes are proposed for each of the three maps and the convergence of the states is established by using the Lyapunov method.Furthermore,a combination synchronization scheme is proposed whereby a combination of the fractional Rulkov and Chang maps is synchronized to the fractional Zeraoulia-Sprott map.Numerical results are used to confirm the findings of the paper.展开更多
We study a nonlinear elliptic problem with non-local boundary conditions and Ll-data. We prove an existence and uniqueness result of an entropy solution.
In this work, we are interested to obtain some result of existence and nonex- istence of positive weak solution for the following p-Laplacian system {-△piui=λifi（u1,^…,um）,inΩ, i=1,...,m, ui=0,on δΩ,Vi=1,…,...In this work, we are interested to obtain some result of existence and nonex- istence of positive weak solution for the following p-Laplacian system {-△piui=λifi（u1,^…,um）,inΩ, i=1,...,m, ui=0,on δΩ,Vi=1,…,m,where △piz = div（｜△z｜^pi-2△Z）, Pi ≥ 1,λi,1 ≤ i ≤ m are a positive parameter, and Ω is a bounded domain in IR^N with smooth boundary δΩ. The proof of the main results is based to the method of sub-supersolutions.展开更多
基金funded by Umm Al-Qura University,Saudi Arabia under grant number:25UQU4300346GSSR08.
文摘This study presents an advanced method for post-mortem person identification using the segmentation of skeletal structures from chest X-ray images.The proposed approach employs the Attention U-Net architecture,enhanced with gated attention mechanisms,to refine segmentation by emphasizing spatially relevant anatomical features while suppressing irrelevant details.By isolating skeletal structures which remain stable over time compared to soft tissues,this method leverages bones as reliable biometric markers for identity verification.The model integrates custom-designed encoder and decoder blocks with attention gates,achieving high segmentation precision.To evaluate the impact of architectural choices,we conducted an ablation study comparing Attention U-Net with and without attentionmechanisms,alongside an analysis of data augmentation effects.Training and evaluation were performed on a curated chest X-ray dataset,with segmentation performance measured using Dice score,precision,and loss functions,achieving over 98% precision and 94% Dice score.The extracted bone structures were further processed to derive unique biometric patterns,enabling robust and privacy-preserving person identification.Our findings highlight the effectiveness of attentionmechanisms in improving segmentation accuracy and underscore the potential of chest bonebased biometrics in forensic and medical imaging.This work paves the way for integrating artificial intelligence into real-world forensic workflows,offering a non-invasive and reliable solution for post-mortem identification.
基金funded by Umm Al-Qura University,Saudi Arabia under grant number:25UQU4300346GSSR05.
文摘These days,social media has grown to be an integral part of people’s lives.However,it involves the possibility of exposure to“fake news”,which may contain information that is intentionally or inaccurately false to promote particular political or economic interests.The main objective of this work is to use the co-attention mechanism in a Combined Graph neural network model(CMCG)to capture the relationship between user profile features and user preferences in order to detect fake news and examine the influence of various social media features on fake news detection.The proposed approach includes three modules.The first one creates a Graph Neural Network(GNN)based model to learn user profile properties,while the second module encodes news content,user historical posts,and news sharing cascading on social media as user preferences GNN-based model.The inter-dependencies between user profiles and user preferences are handled through the third module using a co-attention mechanism for capturing the relationship between the two GNN-based models.We conducted several experiments on two commonly used fake news datasets,Politifact and Gossipcop,where our approach achieved 98.53%accuracy on the Gossipcop dataset and 96.77%accuracy on the Politifact dataset.These results illustrate the effectiveness of the CMCG approach for fake news detection,as it combines various information from different modalities to achieve relatively high performances.
文摘This study presents a two-echelon inventory routing problem (2E-IRP) with an end-of-tour replenishment (ETR) policy whose distribution network consists of a supplier, several distribution centers (DCs) and several retailers on a multi-period planning horizon. A formulation of the problem based on vehicle indices is proposed in the form of a mixed integer linear program (MILP). The mathematical model of the problem is solved using a branch and cut (B&C) algorithm. The results of the tests are compared to the results of a branch and price (B&P) algorithm from the literature on 2E-IRP with a classical distribution policy. The results of the tests show that the B&C algorithm solves 197 out of 200 instances (98.5%). The comparison of the B&C and B&P results shows that 185 best solutions are obtained with the B&C algorithm on 197 instances (93.9%). Overall, the B&C algorithm achieves cost reductions ranging from 0.26% to 41.44% compared to the classic 2E-IRP results solved with the B&P algorithm, with an overall average reduction of 18.08%.
文摘Pancreatic cancer is a highly lethal disease with a ge-netic susceptibility and familial aggregation found in 3%-16% of patients. Early diagnosis remains the only hope for curative treatment and improvement of prog-nosis. This can be reached by the implementation of an intensive screening program, actually recommended for individuals at high-risk for pancreatic cancer de-velopment. The aim of this strategy is to identify pre-malignant precursors or asymptomatic pancreatic can-cer lesions, curable by surgery. Endoscopic ultrasound (EUS) with or without fine needle aspiration(FNA) seems to be the most promising technique for early de-tection of pancreatic cancer. It has been described as a highly sensitive and accurate tool, especially for small and cystic lesions. Pancreatic intraepithelial neoplasia, a precursor lesion which is highly represented in high-risk individuals, seems to have characteristics chronic pancreatitis-like changes well detected by EUS. Many screening protocols have demonstrated high diagnostic yields for pancreatic pre-malignant lesions, allowing prophylactic pancreatectomies. However, it shows a high interobserver variety even among experienced en-dosonographers and a low sensitivity in case of chronic pancreatitis. Some new techniques such as contrast-en-hanced harmonic EUS, computer-aided diagnostic tech-niques, confocal laser endomicroscopy miniprobe andthe detection of DNA abnormalities or protein markersby FNA, promise improvement of the diagnostic yield ofEUS. As the resolution of imaging improves and as ourknowledge of precursor lesions grows, we believe thatEUS could become the most suitable method to detectcurable pancreatic neoplasms in correctly identifiedasymptomatic at-risk patients.
文摘A new synchronization scheme for chaotic（hyperchaotic） maps with different dimensions is presented.Specifically,given a drive system map with dimension n and a response system with dimension m,the proposed approach enables each drive system state to be synchronized with a linear response combination of the response system states.The method,based on the Lyapunov stability theory and the pole placement technique,presents some useful features：（i） it enables synchronization to be achieved for both cases of n 〈 m and n 〉 m;（ii） it is rigorous,being based on theorems;（iii） it can be readily applied to any chaotic（hyperchaotic） maps defined to date.Finally,the capability of the approach is illustrated by synchronization examples between the two-dimensional H′enon map（as the drive system） and the three-dimensional hyperchaotic Wang map（as the response system）,and the three-dimensional H′enon-like map（as the drive system） and the two-dimensional Lorenz discrete-time system（as the response system）.
文摘In this paper, we construct a backward difference scheme for a class of SIR epidemic model with general incidence f . The step sizeτ used in our discretization is one. The dynamical properties are investigated (positivity and the boundedness of solution). By constructing the Lyapunov function, the general incidence function f must satisfy certain assumptions, under which, we establish the global stability of endemic equilibrium when R0 >1. The global stability of diseases-free equilibrium is also established when R0 ≤1. In addition we present numerical results of the continuous and discrete model of the different class according to the value of basic reproduction number R0.
基金The author Adel Ouannas was supported by the Directorate General for Scientific Research and Technological Development of Algeria.The author Shaher Momani was supported by Ajman University in UAE.
文摘This paper studies the dynamics of a new fractional-order discrete system based on the Caputo-like difference operator.This is the first study to explore a three-dimensional fractional-order discrete chaotic system without equilibrium.Through phase portrait,bifurcation diagrams,and largest Lyapunov exponents,it is shown that the proposed fractional-order discrete system exhibits a range of different dynamical behaviors.Also,different tests are used to confirm the existence of chaos,such as 0-1 test and C0 complexity.In addition,the quantification of the level of chaos in the new fractional-order discrete system is measured by the approximate entropy technique.Furthermore,based on the fractional linearization method,a one-dimensional controller to stabilize the new system is proposed.Numerical results are presented to validate the findings of the paper.
基金This work was supported by the Directorate-General for Scientific Research and Technological Development(DGRSDT)The authors wish to acknowledge the editor and anonymous reviewers for their insightful comments,which have improved the quality of this publication.The authors also acknowledge Prof.Carlos Castro,from Polytechnic University of Madrid(Spain),for a fruitful discussion and the referee for the remarks that have improved the final version of the paper.
文摘The purpose of this paper is to extend the notion of regional controllability for hyperbolic parameter dependent systems.The key idea is the characterization of the averaged regional control with minimal energy.This control steers the state average(with respect to such a parameter)towards the desired state only on a given part of the system evolution domain.In this paper,we give the precis definition and the properties of this new concept.Then,we use an approach based on an extension of the Hilbert uniqueness method devoted to the calculation of the control in two different cases:zone control and pointwise control.
文摘In this paper, we develop a mathematical model of the COVID-19 pandemic in Burkina Faso. We use real data from Burkina Faso National Health Commission against COVID-19 to predict the dynamic of the disease and also the cumulative number of reported cases. We use public policies in model in order to reduce the contact rate, this allows to show how the reduction of the daily report of infectious cases goes, so we would like to draw the attention of decision makers for a rapid treatment of reported cases.
文摘We examined persistence in seven common preventive health practices for a nationally representative sample of Medicare beneficiaries over 4-year observation periods. Six panels from the 1997-2005 Medicare Current Beneficiary Survey (MCBS) were used resulting in 13,913 unique individuals with ages ranging from below 65 (disabled) to over 80 years old. Persistence in behavior was defined as the proportion of the observation period beneficiaries participated in each activity. We estimated behavioral persistence as a function of baseline demographic, socioeconomic, and health characteristics using multivariate regression analysis. Beneficiaries were most persistent in smoking abstinence (81% reported not smoking) and least persistent with routine exercise (47% reporting none). From multivariate regression results, there was greater persistence among beneficiaries who were married when compared to those living alone (p 300% FPL compared to <100% FPL all p < 0.01). Increasing age (greater than 80 compared to 65 - 69) was associated with increased compliance in influenza vaccination and smoking cessation (p < 0.01) while negatively associated with weekly exercise and cancer screenings (p < 0.01). Medicare beneficiaries are inconsistently persistent with common preventive health practices.
文摘In this paper, we study a class of Prigozhin equation for growing sandpile problem subject to local and a non-local boundary condition. The problem is a generalized model for a growing sandpile problem with Neumann boundary condition (see <a href="#ref1">[1]</a>). By the semi-group theory, we prove the existence and uniqueness of the solution for the model and thanks to a duality method we do the numerical analysis of the problem. We finish our work by doing numerical simulations to validate our theoretical results.
文摘In this paper, we study the impact of copying data in GPU computing. GPU computing allows implementing parallel computations at low cost: a GPU can be purchased at under USD 500. Many studies have shown that GPU can be used to speed up the calculations. But for algorithms requiring doing a part of the calculations on GPU and another part on CPU, alternately, latency due to the copy of the data is a performance degradation factor. To illustrate this, we consider the Dijkstra’s algorithm on the shortest path used in solving optimization problems. This algorithm is very heavy to run on sequential machine. So, we are considering a parallel approach on GPU. Note that Dijkstra’s algorithm has been subject of many implementations on GPU. In the present work, we use two platforms with external GPU. Graphs are represented in adjacency matrix. During the computation of this algorithm, intermediates results are copied from GPU to CPU or from CPU to GPU. The purpose of this work is to measure the impact of these copies in the overall performance of the algorithm. For that we calculate time due to the copying data’s implementation;then we compare results with implementation computing only on CPU memory (zero-copy). The real impact shown by experiments demonstrates the interest of this study. GP-GPU programmers have to think that they will use either memory zero-copy or GPU memory. The challenge for GPU’s manufacturers is how to reduce this impact.
文摘In this paper, we present parallel programming approaches to calculate the values of the cells in matrix’s scoring used in the Smith-Waterman’s algorithm for sequence alignment. This algorithm, well known in bioinformatics for its applications, is unfortunately time-consuming on a serial computer. We use formulation based on anti-diagonals structure of data. This representation focuses on parallelizable parts of the algorithm without changing the initial formulation of the algorithm. Approaching data in that way give us a formulation more flexible. To examine this approach, we encode it in OpenMP and Cuda C. The performance obtained shows the interest of our paper.
文摘This article examines the architecture of software-defined networks (SDN) and its implications for the modern management of communications infrastructures. By decoupling the control plane from the data plane, SDN offers increased flexibility and programmability, enabling rapid adaptation to changing user requirements. However, this new approach poses significant challenges in terms of security, fault tolerance, and interoperability. This paper highlights these challenges and explores current strategies to ensure the resilience and reliability of SDN networks in the face of threats and failures. In addition, we analyze the future outlook for SDN and the importance of integrating robust security solutions into these infrastructures.
文摘This paper addresses the problem of identifying the unknown diffusion coefficient in a semilinear parabolic equation with incomplete initial condition.We propose an optimal control approach using the no-regret control method and the adapted low-regret control.Our approach provides a fullcharacterisation of the unknown diffusion coefficient independent of the missing initial condition.We also present an optimality system that describes the adapted low-regret control and use it to find a fuil description of the no-regret control by taking the limit of the sequence of adapted low-regret controls.
基金supported by the Natural Science Foundation of China under Grant Nos.11726624,11726623,61473237the Natural Science Basic Research Plan in Shaxanxi Province of China under Grant No.2018GY-091the Natural Science Basic Research Plan in Shandong Province of China under Grant No.ZR2017PA008。
文摘This paper proposes three fractional discrete chaotic systems based on the Rulkov,Chang,and Zeraoulia–Sprott rational maps.The dynamics of the proposed maps are investigated by means of phase plots and bifurcations diagrams.Adaptive stabilization schemes are proposed for each of the three maps and the convergence of the states is established by using the Lyapunov method.Furthermore,a combination synchronization scheme is proposed whereby a combination of the fractional Rulkov and Chang maps is synchronized to the fractional Zeraoulia-Sprott map.Numerical results are used to confirm the findings of the paper.
文摘We study a nonlinear elliptic problem with non-local boundary conditions and Ll-data. We prove an existence and uniqueness result of an entropy solution.
文摘In this work, we are interested to obtain some result of existence and nonex- istence of positive weak solution for the following p-Laplacian system {-△piui=λifi（u1,^…,um）,inΩ, i=1,...,m, ui=0,on δΩ,Vi=1,…,m,where △piz = div（｜△z｜^pi-2△Z）, Pi ≥ 1,λi,1 ≤ i ≤ m are a positive parameter, and Ω is a bounded domain in IR^N with smooth boundary δΩ. The proof of the main results is based to the method of sub-supersolutions.
