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Development of SNP parentage assignment techniques in the yellowfin seabream Acanthopagrus latus
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作者 Hongbo Zhao Liangmin Huang +3 位作者 Jing Zhang Songyuan You Qingmin Zeng Xiande Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期151-155,共5页
Acanthopagrus latus is an essential aquaculture species on the south coast of China.However,there is a lack of systematic breeding of A.latus,which considerably limits the sustainable development of A.latus.As a resul... Acanthopagrus latus is an essential aquaculture species on the south coast of China.However,there is a lack of systematic breeding of A.latus,which considerably limits the sustainable development of A.latus.As a result,genetic improvements are urgently needed to breed new strains of A.latus with rapid growth and strong resistance to disease.During selective breeding,it is necessary to estimate the genetic parameters of the target trait,which in turn depends on an accurate disentangled pedigree for the selective population.Therefore,it is necessary to establish the parentage assignment technique for A.latus.In this study,95 individuals selected from their parents and their 14 families were used as experimental material.SNPs were developed by genome resequencing,and highly polymorphic SNPs were screened on the basis of optimized filtering parameters.A total of 14392738 SNPs were discovered and 205 SNPs were selected for parentage assignment using the CERVUS software.In the model where the gender of the parents is known,the assignment success rate is 98.61%for the male parent,97.22%for the female parent,and 95.83%for the parent pair.In the model where the gender of the parents is unknown,the assignment success rate is 100%for a single parent and 90.28%for the parent pair.The results of this study were expected to serve as a reference for the breeding of new varieties of A.latus. 展开更多
关键词 Acanthopagrus latus parentage assignment SNP Genome re-sequencing
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Channel assignment and power allocation for throughput improvement with PPO in B5G heterogeneous edge networks
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作者 Xiaoming He Yingchi Mao +3 位作者 Yinqiu Liu Ping Ping Yan Hong Han Hu 《Digital Communications and Networks》 SCIE CSCD 2024年第1期109-116,共8页
In Beyond the Fifth Generation(B5G)heterogeneous edge networks,numerous users are multiplexed on a channel or served on the same frequency resource block,in which case the transmitter applies coding and the receiver u... In Beyond the Fifth Generation(B5G)heterogeneous edge networks,numerous users are multiplexed on a channel or served on the same frequency resource block,in which case the transmitter applies coding and the receiver uses interference cancellation.Unfortunately,uncoordinated radio resource allocation can reduce system throughput and lead to user inequity,for this reason,in this paper,channel allocation and power allocation problems are formulated to maximize the system sum rate and minimum user achievable rate.Since the construction model is non-convex and the response variables are high-dimensional,a distributed Deep Reinforcement Learning(DRL)framework called distributed Proximal Policy Optimization(PPO)is proposed to allocate or assign resources.Specifically,several simulated agents are trained in a heterogeneous environment to find robust behaviors that perform well in channel assignment and power allocation.Moreover,agents in the collection stage slow down,which hinders the learning of other agents.Therefore,a preemption strategy is further proposed in this paper to optimize the distributed PPO,form DP-PPO and successfully mitigate the straggler problem.The experimental results show that our mechanism named DP-PPO improves the performance over other DRL methods. 展开更多
关键词 B5G Heterogeneous edge networks PPO Channel assignment Power allocation THROUGHPUT
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A self-organization formation configuration based assignment probability and collision detection
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作者 SONG Wei WANG Tong +1 位作者 YANG Guangxin ZHANG Peng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期222-232,共11页
The formation control of multiple unmanned aerial vehicles(multi-UAVs)has always been a research hotspot.Based on the straight line trajectory,a multi-UAVs target point assignment algorithm based on the assignment pro... The formation control of multiple unmanned aerial vehicles(multi-UAVs)has always been a research hotspot.Based on the straight line trajectory,a multi-UAVs target point assignment algorithm based on the assignment probability is proposed to achieve the shortest overall formation path of multi-UAVs with low complexity and reduce the energy consumption.In order to avoid the collision between UAVs in the formation process,the concept of safety ball is introduced,and the collision detection based on continuous motion of two time slots and the lane occupation detection after motion is proposed to avoid collision between UAVs.Based on the idea of game theory,a method of UAV motion form setting based on the maximization of interests is proposed,including the maximization of self-interest and the maximization of formation interest is proposed,so that multi-UAVs can complete the formation task quickly and reasonably with the linear trajectory assigned in advance.Finally,through simulation verification,the multi-UAVs target assignment algorithm based on the assignment probability proposed in this paper can effectively reduce the total path length,and the UAV motion selection method based on the maximization interests can effectively complete the task formation. 展开更多
关键词 straight line trajectory assignment probability collision detection lane occupation detection maximization of interests
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Reinforcement Learning Based Quantization Strategy Optimal Assignment Algorithm for Mixed Precision
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作者 Yuejiao Wang Zhong Ma +2 位作者 Chaojie Yang Yu Yang Lu Wei 《Computers, Materials & Continua》 SCIE EI 2024年第4期819-836,共18页
The quantization algorithm compresses the original network by reducing the numerical bit width of the model,which improves the computation speed. Because different layers have different redundancy and sensitivity to d... The quantization algorithm compresses the original network by reducing the numerical bit width of the model,which improves the computation speed. Because different layers have different redundancy and sensitivity to databit width. Reducing the data bit width will result in a loss of accuracy. Therefore, it is difficult to determinethe optimal bit width for different parts of the network with guaranteed accuracy. Mixed precision quantizationcan effectively reduce the amount of computation while keeping the model accuracy basically unchanged. In thispaper, a hardware-aware mixed precision quantization strategy optimal assignment algorithm adapted to low bitwidth is proposed, and reinforcement learning is used to automatically predict the mixed precision that meets theconstraints of hardware resources. In the state-space design, the standard deviation of weights is used to measurethe distribution difference of data, the execution speed feedback of simulated neural network accelerator inferenceis used as the environment to limit the action space of the agent, and the accuracy of the quantization model afterretraining is used as the reward function to guide the agent to carry out deep reinforcement learning training. Theexperimental results show that the proposed method obtains a suitable model layer-by-layer quantization strategyunder the condition that the computational resources are satisfied, and themodel accuracy is effectively improved.The proposed method has strong intelligence and certain universality and has strong application potential in thefield of mixed precision quantization and embedded neural network model deployment. 展开更多
关键词 Mixed precision quantization quantization strategy optimal assignment reinforcement learning neural network model deployment
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UAVs cooperative task assignment and trajectory optimization with safety and time constraints 被引量:2
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作者 Duo Zheng Yun-fei Zhang +1 位作者 Fan Li Peng Cheng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第2期149-161,共13页
This paper proposes new methods and strategies for Multi-UAVs cooperative attacks with safety and time constraints in a complex environment.Delaunay triangle is designed to construct a map of the complex flight enviro... This paper proposes new methods and strategies for Multi-UAVs cooperative attacks with safety and time constraints in a complex environment.Delaunay triangle is designed to construct a map of the complex flight environment for aerial vehicles.Delaunay-Map,Safe Flight Corridor(SFC),and Relative Safe Flight Corridor(RSFC)are applied to ensure each UAV flight trajectory's safety.By using such techniques,it is possible to avoid the collision with obstacles and collision between UAVs.Bezier-curve is further developed to ensure that multi-UAVs can simultaneously reach the target at the specified time,and the trajectory is within the flight corridor.The trajectory tracking controller is also designed based on model predictive control to track the planned trajectory accurately.The simulation and experiment results are presented to verifying developed strategies of Multi-UAV cooperative attacks. 展开更多
关键词 MULTI-UAV Cooperative attacks Task assignment Trajectory optimization Safety constraints
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Task assignment in ground-to-air confrontation based on multiagent deep reinforcement learning 被引量:3
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作者 Jia-yi Liu Gang Wang +2 位作者 Qiang Fu Shao-hua Yue Si-yuan Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第1期210-219,共10页
The scale of ground-to-air confrontation task assignments is large and needs to deal with many concurrent task assignments and random events.Aiming at the problems where existing task assignment methods are applied to... The scale of ground-to-air confrontation task assignments is large and needs to deal with many concurrent task assignments and random events.Aiming at the problems where existing task assignment methods are applied to ground-to-air confrontation,there is low efficiency in dealing with complex tasks,and there are interactive conflicts in multiagent systems.This study proposes a multiagent architecture based on a one-general agent with multiple narrow agents(OGMN)to reduce task assignment conflicts.Considering the slow speed of traditional dynamic task assignment algorithms,this paper proposes the proximal policy optimization for task assignment of general and narrow agents(PPOTAGNA)algorithm.The algorithm based on the idea of the optimal assignment strategy algorithm and combined with the training framework of deep reinforcement learning(DRL)adds a multihead attention mechanism and a stage reward mechanism to the bilateral band clipping PPO algorithm to solve the problem of low training efficiency.Finally,simulation experiments are carried out in the digital battlefield.The multiagent architecture based on OGMN combined with the PPO-TAGNA algorithm can obtain higher rewards faster and has a higher win ratio.By analyzing agent behavior,the efficiency,superiority and rationality of resource utilization of this method are verified. 展开更多
关键词 Ground-to-air confrontation Task assignment General and narrow agents Deep reinforcement learning Proximal policy optimization(PPO)
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Joint target assignment and power allocation in the netted C-MIMO radar when tracking multi-targets in the presence of self-defense blanket jamming 被引量:1
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作者 Zhengjie Li Junwei Xie +1 位作者 Haowei Zhang Jiahao Xie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期414-427,共14页
The netted radar system(NRS)has been proved to possess unique advantages in anti-jamming and improving target tracking performance.Effective resource management can greatly ensure the combat capability of the NRS.In t... The netted radar system(NRS)has been proved to possess unique advantages in anti-jamming and improving target tracking performance.Effective resource management can greatly ensure the combat capability of the NRS.In this paper,based on the netted collocated multiple input multiple output(CMIMO)radar,an effective joint target assignment and power allocation(JTAPA)strategy for tracking multi-targets under self-defense blanket jamming is proposed.An architecture based on the distributed fusion is used in the radar network to estimate target state parameters.By deriving the predicted conditional Cramer-Rao lower bound(PC-CRLB)based on the obtained state estimation information,the objective function is formulated.To maximize the worst case tracking accuracy,the proposed JTAPA strategy implements an online target assignment and power allocation of all active nodes,subject to some resource constraints.Since the formulated JTAPA is non-convex,we propose an efficient two-step solution strategy.In terms of the simulation results,the proposed algorithm can effectively improve tracking performance in the worst case. 展开更多
关键词 Netted radar system MIMO Target assignment Power allocation Multi-targets tracking Self-defense blanket jamming
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Shuffled frog leaping algorithm with non-dominated sorting for dynamic weapon-target assignment 被引量:1
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作者 ZHAO Yang LIU Jicheng +1 位作者 JIANG Ju ZHEN Ziyang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期1007-1019,共13页
The dynamic weapon target assignment(DWTA)problem is of great significance in modern air combat.However,DWTA is a highly complex constrained multi-objective combinatorial optimization problem.An improved elitist non-d... The dynamic weapon target assignment(DWTA)problem is of great significance in modern air combat.However,DWTA is a highly complex constrained multi-objective combinatorial optimization problem.An improved elitist non-dominated sorting genetic algorithm-II(NSGA-II)called the non-dominated shuffled frog leaping algorithm(NSFLA)is proposed to maximize damage to enemy targets and minimize the self-threat in air combat constraints.In NSFLA,the shuffled frog leaping algorithm(SFLA)is introduced to NSGA-II to replace the inside evolutionary scheme of the genetic algorithm(GA),displaying low optimization speed and heterogeneous space search defects.Two improvements have also been raised to promote the internal optimization performance of SFLA.Firstly,the local evolution scheme,a novel crossover mechanism,ensures that each individual participates in updating instead of only the worst ones,which can expand the diversity of the population.Secondly,a discrete adaptive mutation algorithm based on the function change rate is applied to balance the global and local search.Finally,the scheme is verified in various air combat scenarios.The results show that the proposed NSFLA has apparent advantages in solution quality and efficiency,especially in many aircraft and the dynamic air combat environment. 展开更多
关键词 dynamic weapon-target assignment(DWTA)problem shuffled frog leaping algorithm(SFLA) air combat research
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An Air Defense Weapon Target Assignment Method Based on Multi-Objective Artificial Bee Colony Algorithm 被引量:1
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作者 Huaixi Xing Qinghua Xing 《Computers, Materials & Continua》 SCIE EI 2023年第9期2685-2705,共21页
With the advancement of combat equipment technology and combat concepts,new requirements have been put forward for air defense operations during a group target attack.To achieve high-efficiency and lowloss defensive o... With the advancement of combat equipment technology and combat concepts,new requirements have been put forward for air defense operations during a group target attack.To achieve high-efficiency and lowloss defensive operations,a reasonable air defense weapon assignment strategy is a key step.In this paper,a multi-objective and multi-constraints weapon target assignment(WTA)model is established that aims to minimize the defensive resource loss,minimize total weapon consumption,and minimize the target residual effectiveness.An optimization framework of air defense weapon mission scheduling based on the multiobjective artificial bee colony(MOABC)algorithm is proposed.The solution for point-to-point saturated attack targets at different operational scales is achieved by encoding the nectar with real numbers.Simulations are performed for an imagined air defense scenario,where air defense weapons are saturated.The non-dominated solution sets are obtained by the MOABC algorithm to meet the operational demand.In the case where there are more weapons than targets,more diverse assignment schemes can be selected.According to the inverse generation distance(IGD)index,the convergence and diversity for the solutions of the non-dominated sorting genetic algorithm III(NSGA-III)algorithm and the MOABC algorithm are compared and analyzed.The results prove that the MOABC algorithm has better convergence and the solutions are more evenly distributed among the solution space. 展开更多
关键词 Weapon target assignment multi-objective artificial bee colony air defense defensive resource loss total weapon consumption target residual effectiveness
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SiamDLA: Dynamic Label Assignment for Siamese Visual Tracking
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作者 Yannan Cai Ke Tan Zhenzhong Wei 《Computers, Materials & Continua》 SCIE EI 2023年第4期1621-1640,共20页
Label assignment refers to determining positive/negative labels foreach sample to supervise the training process. Existing Siamese-based trackersprimarily use fixed label assignment strategies according to human prior... Label assignment refers to determining positive/negative labels foreach sample to supervise the training process. Existing Siamese-based trackersprimarily use fixed label assignment strategies according to human priorknowledge;thus, they can be sensitive to predefined hyperparameters and failto fit the spatial and scale variations of samples. In this study, we first developa novel dynamic label assignment (DLA) module to handle the diverse datadistributions and adaptively distinguish the foreground from the backgroundbased on the statistical characteristics of the target in visual object tracking.The core of DLA module is a two-step selection mechanism. The first stepselects candidate samples according to the Euclidean distance between trainingsamples and ground truth, and the second step selects positive/negativesamples based on the mean and standard deviation of candidate samples.The proposed approach is general-purpose and can be easily integrated intoanchor-based and anchor-free trackers for optimal sample-label matching.According to extensive experimental findings, Siamese-based trackers withDLA modules can refine target locations and outperformbaseline trackers onOTB100, VOT2019, UAV123 and LaSOT. Particularly, DLA-SiamRPN++improves SiamRPN++ by 1% AUC and DLA-SiamCAR improves Siam-CAR by 2.5% AUC on OTB100. Furthermore, hyper-parameters analysisexperiments show that DLA module hardly increases spatio-temporal complexity,the proposed approach maintains the same speed as the originaltracker without additional overhead. 展开更多
关键词 Siamese network label assignment single object tracking anchorbased anchor-free
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An Intelligent Algorithm for Solving Weapon-Target Assignment Problem:DDPG-DNPE Algorithm
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作者 Tengda Li Gang Wang +3 位作者 Qiang Fu Xiangke Guo Minrui Zhao Xiangyu Liu 《Computers, Materials & Continua》 SCIE EI 2023年第9期3499-3522,共24页
Aiming at the problems of traditional dynamic weapon-target assignment algorithms in command decisionmaking,such as large computational amount,slow solution speed,and low calculation accuracy,combined with deep reinfo... Aiming at the problems of traditional dynamic weapon-target assignment algorithms in command decisionmaking,such as large computational amount,slow solution speed,and low calculation accuracy,combined with deep reinforcement learning theory,an improved Deep Deterministic Policy Gradient algorithm with dual noise and prioritized experience replay is proposed,which uses a double noise mechanism to expand the search range of the action,and introduces a priority experience playback mechanism to effectively achieve data utilization.Finally,the algorithm is simulated and validated on the ground-to-air countermeasures digital battlefield.The results of the experiment show that,under the framework of the deep neural network for intelligent weapon-target assignment proposed in this paper,compared to the traditional RELU algorithm,the agent trained with reinforcement learning algorithms,such asDeepDeterministic Policy Gradient algorithm,Asynchronous Advantage Actor-Critic algorithm,Deep Q Network algorithm performs better.It shows that the use of deep reinforcement learning algorithms to solve the weapon-target assignment problem in the field of air defense operations is scientific.In contrast to other reinforcement learning algorithms,the agent trained by the improved Deep Deterministic Policy Gradient algorithm has a higher win rate and reward in confrontation,and the use of weapon resources is more efficient.It shows that the model and algorithm have certain superiority and rationality.The results of this paper provide new ideas for solving the problemof weapon-target assignment in air defense combat command decisions. 展开更多
关键词 Weapon-target assignment DDPG-DNPE algorithm deep reinforcement learning intelligent decision-making GRU
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Automatic Team Assignment and Jersey Number Recognition in Football Videos
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作者 Ragd Alhejaily Rahaf Alhejaily +2 位作者 Mai Almdahrsh Shareefah Alessa Saleh Albelwi 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2669-2684,共16页
Football is one of the most-watched sports,but analyzing players’per-formance is currently difficult and labor intensive.Performance analysis is done manually,which means that someone must watch video recordings and ... Football is one of the most-watched sports,but analyzing players’per-formance is currently difficult and labor intensive.Performance analysis is done manually,which means that someone must watch video recordings and then log each player’s performance.This includes the number of passes and shots taken by each player,the location of the action,and whether or not the play had a successful outcome.Due to the time-consuming nature of manual analyses,interest in automatic analysis tools is high despite the many interdependent phases involved,such as pitch segmentation,player and ball detection,assigning players to their teams,identifying individual players,activity recognition,etc.This paper proposes a system for developing an automatic video analysis tool for sports.The proposed system is the first to integrate multiple phases,such as segmenting the field,detecting the players and the ball,assigning players to their teams,and iden-tifying players’jersey numbers.In team assignment,this research employed unsu-pervised learning based on convolutional autoencoders(CAEs)to learn discriminative latent representations and minimize the latent embedding distance between the players on the same team while simultaneously maximizing the dis-tance between those on opposing teams.This paper also created a highly accurate approach for the real-time detection of the ball.Furthermore,it also addressed the lack of jersey number datasets by creating a new dataset with more than 6,500 images for numbers ranging from 0 to 99.Since achieving a high perfor-mance in deep learning requires a large training set,and the collected dataset was not enough,this research utilized transfer learning(TL)to first pretrain the jersey number detection model on another large dataset and then fine-tune it on the target dataset to increase the accuracy.To test the proposed system,this paper presents a comprehensive evaluation of its individual stages as well as of the sys-tem as a whole. 展开更多
关键词 Football video analysis player detection ball detection team assignment jersey number recognition
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Bee Colony Optimization Algorithm for Routing and Wavelength Assignment Based on Directional Guidance in Satellite Optical Networks
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作者 Mai Yang Qi Zhang +8 位作者 Haipeng Yao Ran Gao Xiangjun Xin Feng Tian Weiying Feng Dong Chen Fu Wang Qinghua Tian Jinxi Qian 《China Communications》 SCIE CSCD 2023年第7期89-107,共19页
With the development of satellite communication,in order to solve the problems of shortage of on-board resources and refinement of delay requirements to improve the communication performance of satellite optical netwo... With the development of satellite communication,in order to solve the problems of shortage of on-board resources and refinement of delay requirements to improve the communication performance of satellite optical networks,this paper proposes a bee colony optimization algorithm for routing and wavelength assignment based on directional guidance(DBCO-RWA)in satellite optical networks.In D-BCORWA,directional guidance based on relative position and link load is defined,and then the link cost function in the path search stage is established based on the directional guidance factor.Finally,feasible solutions are expanded in the global optimization stage.The wavelength utilization,communication success probability,blocking rate,communication hops and convergence characteristic are simulated.The results show that the performance of the proposed algorithm is improved compared with existing algorithms. 展开更多
关键词 routing and wavelength assignment satel-lite optical networks bee colony optimization algo-rithm directional guidance feasible solution extension
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Hybrid Policy of Routing and Spectrum Assignment in Elastic Optical Networks
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作者 Joël Adépo Georges Nogbou Anoh Joseph Wognin Vangah 《Open Journal of Applied Sciences》 2023年第12期2387-2394,共8页
The major challenge in elastic optical networks is to determine the path of a connection and to allocate spectral resources on the links of this path. This problem consists of two sub-problems, routing and spectrum al... The major challenge in elastic optical networks is to determine the path of a connection and to allocate spectral resources on the links of this path. This problem consists of two sub-problems, routing and spectrum allocation. In the literature, these sub-problems are solved with a predefined order for all topology node pairs. Recent work proposes hybrid resolution algorithms based on connection demand and network state to provide a solution to these problems. However, the blocking rate of new connection requests has become problematic. In this work, we propose a hybrid routing and spectrum assignment policy to improve blocking rate of new connection requests. The proposed solution consists to change the routing policy of a pair node if the connection request is blocked. This algorithm improves the blocking rate of new connection requests. 展开更多
关键词 ROUTING Spectrum assignment Elastic Optical Network
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^(1)H and ^(13)C NMR spectral assignments for low-concentration bile acids in biological samples
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作者 Hong Lin Junbo He +1 位作者 Weinong Zhang Huiru Tang 《Magnetic Resonance Letters》 2023年第4期277-285,共9页
Bile acids are the main body of enterohepatic circulation in vivo.They have essential functions such as emulsifying fat,bacteriostasis and regulating multiple metabolic pathways as signal molecules.However,the assignm... Bile acids are the main body of enterohepatic circulation in vivo.They have essential functions such as emulsifying fat,bacteriostasis and regulating multiple metabolic pathways as signal molecules.However,the assignments of NMR signals for some lowconcentration bile acids are still needed.This study combined 1D nuclear magnetic resonance(NMR)and 2D NMR techniques including 1He1H correlation spectroscopy(COSY),1He1H total correlation spectroscopy(TOCSY),1H J-resolved spectroscopy(J-Res),1He13C heteronuclear single quantum coherence spectroscopy(HSQC),and 1He13C heteronuclear multiple bond correlation spectroscopy(HMBC)to assign the 1H and 13C signals of six bile acids in aqueous solution at physiological pH(~7.4)and nine bile acids in methanol.These data are of importance to the NMR-based studies on lipid digestion,absorption,and metabolism. 展开更多
关键词 Bile acids ^(1)H NMR ^(2)D NMR Signal assignments
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Bus frequency optimization in a large-scale multi-modal transportation system:integrating 3D-MFD and dynamic traffic assignment
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作者 Kai Yuan Dandan Cui Jiancheng Long 《Digital Transportation and Safety》 2023年第4期241-252,共12页
A properly designed public transport system is expected to improve traffic efficiency.A high-frequency bus service would decrease the waiting time for passengers,but the interaction between buses and cars might result... A properly designed public transport system is expected to improve traffic efficiency.A high-frequency bus service would decrease the waiting time for passengers,but the interaction between buses and cars might result in more serious congestion.On the other hand,a low-frequency bus service would increase the waiting time for passengers and would not reduce the use of private cars.It is important to strike a balance between high and low frequencies in order to minimize the total delays for all road users.It is critical to formulate the impacts of bus frequency on congestion dynamics and mode choices.However,as far as the authors know,most proposed bus frequency optimization formulations are based on static demand and the Bureau of Public Roads function,and do not properly consider the congestion dynamics and their impacts on mode choices.To fill this gap,this paper proposes a bi-level optimization model.A three-dimensional Macroscopic Fundamental Diagram based modeling approach is developed to capture the bi-modal congestion dynamics.A variational inequality model for the user equilibrium in mode choices is presented and solved using a double projection algorithm.A surrogate model-based algorithm is used to solve the bi-level programming problem. 展开更多
关键词 Three-dimensional macroscopic fundamental diagram Dynamic traffic assignment Bi-level programming model Double projection algorithm Surrogate model-based algorithm
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基于冗余度和方差的P-Cycle圈构造算法的研究 被引量:1
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作者 孙强 李德莉 任叶 《铁道学报》 EI CAS CSCD 北大核心 2018年第12期101-107,共7页
铁路光传送网络是高速铁路地面基础设施的神经中枢,为避免网络故障给铁路运营带来巨大损失,重点研究光传送网P-Cycle(Pre-configured Cycle)保护技术,提出在圈扩展时以所有候选圈上未保护工作容量的方差、冗余度两个指标为比较标准的RVP... 铁路光传送网络是高速铁路地面基础设施的神经中枢,为避免网络故障给铁路运营带来巨大损失,重点研究光传送网P-Cycle(Pre-configured Cycle)保护技术,提出在圈扩展时以所有候选圈上未保护工作容量的方差、冗余度两个指标为比较标准的RVPA(Redundancy and Variance Based P-Cycle Construction Algorithm)算法。圈扩展的过程中,算法将选择方差与冗余度能同时满足条件的候选圈作为本轮扩展圈,有效限制了完成保护的P-Cycle圈个数;圈扩展停止条件中,当UPL与参数M、冗余度的大小关系满足条件时,则停止圈扩展,从而限制圈上节点数,使圈个数与圈长度得到有效均衡;在仿真过程中,利用泛欧网络拓扑COST239对RVPA算法进行仿真,并对比分析不同M值下的性能。仿真结果表明,在相同空闲资源与待保护工作容量设定下,参数M取0.5时效果最优,并且RVPA算法的保护容量效率、所需圈的个数、算法整体耗时、总冗余度均优于已有的POCA(P-Cycle Optimization Configuration Heuristic Algorithm)算法。 展开更多
关键词 生存性 p-cycle保护 p-cycle圈扩展算法 资源占用 保护容量效率
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抗毁网状WDM网络中的光纤级P-Cycles优化设计
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作者 虞红芳 吴冬凌 +2 位作者 李乐民 林然 陈天罡 《电子科技大学学报》 EI CAS CSCD 北大核心 2007年第2期161-163,216,共4页
为降低保护切换代价和提高故障恢复时间,提出了以光纤级P-Cycle来实现网络保护;研究了工作路由与光纤级P-Cycle放置联合优化的设计问题,给出了ILP数学模型。为降低计算的复杂度,采用了一种简单有效的方法:根据跳数预先选择工作路由候选... 为降低保护切换代价和提高故障恢复时间,提出了以光纤级P-Cycle来实现网络保护;研究了工作路由与光纤级P-Cycle放置联合优化的设计问题,给出了ILP数学模型。为降低计算的复杂度,采用了一种简单有效的方法:根据跳数预先选择工作路由候选集及环的有效性和长度预先选择P-Cycle候选集。仿真结果表明光纤级P-Cycle设计相比于波长级P-Cycle设计保护切换代价大大降低。 展开更多
关键词 光纤级p-cycle 联合优化 预先选择 保护切换代价
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~1H and ^(13)C NMR Assignments for Amlodipine and Risperidone
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作者 杨春晖 李勤 +2 位作者 刘雪辉 赵兴凯 崔育新 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第1期49-52,共4页
Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for t... Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for the two drugs were performed and confirmed by theevidence of J_(HF) and J_(CF). Conclusion The structures of amlodipine and risperidone wereconfirmed by careful analysis of regular 1D and 2D NMR spectroscopy. 展开更多
关键词 NMR assignment fluorine coupling AMLODIPINE RISPERIDONE
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A Discrete-Time Stochastic Traffic Assignment Model
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作者 王炜 朱中 曲大义 《Journal of Southeast University(English Edition)》 EI CAS 2001年第1期13-17,共5页
A discrete time stochastic traffic assignment model is proposed. The model provides a discrete time description of the variations of flows on a road network during a day or a peak period. The congestion effect at li... A discrete time stochastic traffic assignment model is proposed. The model provides a discrete time description of the variations of flows on a road network during a day or a peak period. The congestion effect at links and link junctions are taken into account. The first in first out principle is enforced on all links at all periods of the day. A stochastic user equilibrium assignment is achieved when the tripmaker is unable to find better travel alternatives. A computational procedure is also presented. 展开更多
关键词 stochastic user equilibrium traffic assignment discrete time traffic assignment
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