期刊文献+
共找到122篇文章
< 1 2 7 >
每页显示 20 50 100
An Elite-Class Teaching-Learning-Based Optimization for Reentrant Hybrid Flow Shop Scheduling with Bottleneck Stage
1
作者 Deming Lei Surui Duan +1 位作者 Mingbo Li Jing Wang 《Computers, Materials & Continua》 SCIE EI 2024年第4期47-63,共17页
Bottleneck stage and reentrance often exist in real-life manufacturing processes;however,the previous research rarely addresses these two processing conditions in a scheduling problem.In this study,a reentrant hybrid ... Bottleneck stage and reentrance often exist in real-life manufacturing processes;however,the previous research rarely addresses these two processing conditions in a scheduling problem.In this study,a reentrant hybrid flow shop scheduling problem(RHFSP)with a bottleneck stage is considered,and an elite-class teaching-learning-based optimization(ETLBO)algorithm is proposed to minimize maximum completion time.To produce high-quality solutions,teachers are divided into formal ones and substitute ones,and multiple classes are formed.The teacher phase is composed of teacher competition and teacher teaching.The learner phase is replaced with a reinforcement search of the elite class.Adaptive adjustment on teachers and classes is established based on class quality,which is determined by the number of elite solutions in class.Numerous experimental results demonstrate the effectiveness of new strategies,and ETLBO has a significant advantage in solving the considered RHFSP. 展开更多
关键词 Hybrid flow shop scheduling REENTRANT bottleneck stage teaching-learning-based optimization
下载PDF
Improved multi-scale inverse bottleneck residual network based on triplet parallel attention for apple leaf disease identification
2
作者 Lei Tang Jizheng Yi Xiaoyao Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期901-922,共22页
Accurate diagnosis of apple leaf diseases is crucial for improving the quality of apple production and promoting the development of the apple industry. However, apple leaf diseases do not differ significantly from ima... Accurate diagnosis of apple leaf diseases is crucial for improving the quality of apple production and promoting the development of the apple industry. However, apple leaf diseases do not differ significantly from image texture and structural information. The difficulties in disease feature extraction in complex backgrounds slow the related research progress. To address the problems, this paper proposes an improved multi-scale inverse bottleneck residual network model based on a triplet parallel attention mechanism, which is built upon ResNet-50, while improving and combining the inception module and ResNext inverse bottleneck blocks, to recognize seven types of apple leaf(including six diseases of alternaria leaf spot, brown spot, grey spot, mosaic, rust, scab, and one healthy). First, the 3×3 convolutions in some of the residual modules are replaced by multi-scale residual convolutions, the convolution kernels of different sizes contained in each branch of the multi-scale convolution are applied to extract feature maps of different sizes, and the outputs of these branches are multi-scale fused by summing to enrich the output features of the images. Second, the global layer-wise dynamic coordinated inverse bottleneck structure is used to reduce the network feature loss. The inverse bottleneck structure makes the image information less lossy when transforming from different dimensional feature spaces. The fusion of multi-scale and layer-wise dynamic coordinated inverse bottlenecks makes the model effectively balances computational efficiency and feature representation capability, and more robust with a combination of horizontal and vertical features in the fine identification of apple leaf diseases. Finally, after each improved module, a triplet parallel attention module is integrated with cross-dimensional interactions among channels through rotations and residual transformations, which improves the parallel search efficiency of important features and the recognition rate of the network with relatively small computational costs while the dimensional dependencies are improved. To verify the validity of the model in this paper, we uniformly enhance apple leaf disease images screened from the public data sets of Plant Village, Baidu Flying Paddle, and the Internet. The final processed image count is 14,000. The ablation study, pre-processing comparison, and method comparison are conducted on the processed datasets. The experimental results demonstrate that the proposed method reaches 98.73% accuracy on the adopted datasets, which is 1.82% higher than the classical ResNet-50 model, and 0.29% better than the apple leaf disease datasets before preprocessing. It also achieves competitive results in apple leaf disease identification compared to some state-ofthe-art methods. 展开更多
关键词 multi-scale module inverse bottleneck structure triplet parallel attention apple leaf disease
下载PDF
Efficient control of connected and automated vehicles on a two-lane highway with a moving bottleneck
3
作者 刘华清 姜锐 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期527-536,共10页
This paper investigates the traffic flow of connected and automated vehicles(CAVs)inducing by a moving bottleneck on a two-lane highway.A heuristic rules-based algorithm(HRA)has been used to control the traffic flow u... This paper investigates the traffic flow of connected and automated vehicles(CAVs)inducing by a moving bottleneck on a two-lane highway.A heuristic rules-based algorithm(HRA)has been used to control the traffic flow upstream of the moving bottleneck.In the HRA,some CAVs in the control zone are mapped onto the neighboring lane as virtual ones.To improve the driving comfort,the command acceleration caused by virtual vehicle is restricted.Comparing with the benchmark in which the CAVs change lane as soon as the lane changing condition is met,the HRA significantly improves the traffic flow:the overtaking throughput as well as the outflow rate increases,the travel delay and the fuel consumption decrease,the comfort level could also be improved. 展开更多
关键词 traffic flow connected and automated vehicles moving bottleneck
下载PDF
Bottlenecked ABR信源对ABR速率算法的影响(英文)
4
作者 张琳 张惠民 《应用基础与工程科学学报》 EI CSCD 1999年第4期440-447,共8页
比较研究了一种特殊信源,Bottlenecked ABR信源在ATM 网络中对ABR拥塞控制算法性能的影响.Bottlenecked ABR信源由于某些原因无法做到根据交换网络提供的信息相应改变信元发送速率.由于网络交... 比较研究了一种特殊信源,Bottlenecked ABR信源在ATM 网络中对ABR拥塞控制算法性能的影响.Bottlenecked ABR信源由于某些原因无法做到根据交换网络提供的信息相应改变信元发送速率.由于网络交换节点对此不了解,必然导致对Bottlenecked 信源分配的速率过大而浪费网络资源.当Bottlenecked 信源不再发生信源拥塞情况时,网络又会因为瞬间增加的速率而发生拥塞.本文对不同的ABR拥塞控制算法进行了仿真。 展开更多
关键词 ATM网络 ABR业务 bottlenecked信源
下载PDF
一类推广的Bottleneck问题的多项式算法
5
作者 智丽萍 《滁州学院学报》 2010年第2期12-13,共2页
本文讨论了一类Bottleneck问题,给出了判定最优解的三个定理,并在此基础上给出了一个求最优解的算法和算例,算法的复杂度为O(n2).
关键词 可行解 最优解 bottleneck问题
下载PDF
深度信念网络的Bottleneck特征提取方法 被引量:3
6
作者 谈建慧 景新幸 杨海燕 《桂林电子科技大学学报》 2016年第2期118-122,共5页
为了提升连续语音识别系统的识别率,提出一种基于深度信念网络的Bottleneck特征提取方法。该方法使用对比散度算法,采用无监督的预训练堆叠限制玻尔兹曼机得到网络初始化参数,进而采用反向传播算法,以最大化帧级交叉熵作为训练准则,反... 为了提升连续语音识别系统的识别率,提出一种基于深度信念网络的Bottleneck特征提取方法。该方法使用对比散度算法,采用无监督的预训练堆叠限制玻尔兹曼机得到网络初始化参数,进而采用反向传播算法,以最大化帧级交叉熵作为训练准则,反向迭代对网络参数进行微调。采用上下文相关的三音素模型,以音素错误率大小作为评价系统性能的准则。实验结果表明,所提出的基于深度信念网络提取的Bottleneck特征相对于传统特征更具优越性。 展开更多
关键词 连续语音识别 深度信念网络 bottleneck特征 音素错误率
下载PDF
基于区分性准则的Bottleneck特征及其在LVCSR中的应用 被引量:2
7
作者 刘迪源 郭武 《数据采集与处理》 CSCD 北大核心 2016年第2期331-337,共7页
基于深层神经网络中间层的Bottleneck(BN)特征由于可以采用传统的混合高斯模型-隐马尔可夫建模(Gaussian mixture model-hidden Markov model,GMM-HMM),在大规模连续语音识别中获得了广泛的应用。为了提取区分性的BN特征,本文提出在使... 基于深层神经网络中间层的Bottleneck(BN)特征由于可以采用传统的混合高斯模型-隐马尔可夫建模(Gaussian mixture model-hidden Markov model,GMM-HMM),在大规模连续语音识别中获得了广泛的应用。为了提取区分性的BN特征,本文提出在使用传统的BN特征训练好GMM-HMM模型之后,利用最小音素错误率(Minimum phone error,MPE)准则来优化BN网络参数以及GMM-HMM模型参数。该算法相对于其他区分性训练算法而言,采用的是全部数据作为一个大的数据包,而不是小的包方式来训练深度神经网络,从而可以大大加快训练速度。实验结果表明,优化后的BN特征提取网络比传统方法能获得9%的相对词错误率下降。 展开更多
关键词 语音识别 神经网络 区分性训练 bottleneck特征
下载PDF
Dynamic Prediction Method of Production Logistics Bottleneck Based on Bottleneck Index 被引量:22
8
作者 LIU Mingzhou TANG Juan GE Maogen JIANG Zengqiang HU Jing LING Lin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期710-716,共7页
In modern manufacturing pattern, there are many uncertain factors in the modern manufacturing process, such as changes of product attribute, changes of manufacturing resources' state, and so on, which cause productio... In modern manufacturing pattern, there are many uncertain factors in the modern manufacturing process, such as changes of product attribute, changes of manufacturing resources' state, and so on, which cause production logistics bottleneck frequently shift, and make decisions of production planning and control based on formed bottleneck deviated from practical production process. Considering these factors, present researches mainly apply afterwards control to optimize production process to passively adapt to bottleneck changes If the direction of bottleneck shifting can be accurately forecasted, the transition from afterwards control of chasing bottleneck to beforehand control can be realized. Therefore, aiming at the phenomenon of production logistics bottleneck shifting under uncertain manufacturing circumstances, this paper starts off with dynamic property of capability and requirement and then builds the concepts of bottleneck degree and bottleneck index to describe dynamic bottleneck characteristic of production unit; taken production capability, production load and quality assurance capability into consideration, mathematical model of bottleneck index is established to measure bottleneck degree accurately, consequently, quantitative research on mechanism of production logistics shifting is achieved. Based on bottleneck index, the prediction model of production logistics bottleneck is founded to predict dynamic change of bottleneck accurately. Finally, an example of forecasting and monitoring the production logistics bottleneck in one manufacturing shop is given to testify the validation and practicability of the prediction method. 展开更多
关键词 production logistics bottleneck shifting quality assurance capability bottleneck index prediction model
下载PDF
Modified bottleneck-based heuristic for large-scale job-shop scheduling problems with a single bottleneck 被引量:20
9
作者 Zuo Yan Gu Hanyu Xi Yugeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期556-565,共10页
A modified bottleneck-based (MB) heuristic for large-scale job-shop scheduling problems with a welldefined bottleneck is suggested, which is simpler but more tailored than the shifting bottleneck (SB) procedure. I... A modified bottleneck-based (MB) heuristic for large-scale job-shop scheduling problems with a welldefined bottleneck is suggested, which is simpler but more tailored than the shifting bottleneck (SB) procedure. In this algorithm, the bottleneck is first scheduled optimally while the non-bottleneck machines are subordinated around the solutions of the bottleneck schedule by some effective dispatching rules. Computational results indicate that the MB heuristic can achieve a better tradeoff between solution quality and computational time compared to SB procedure for medium-size problems. Furthermore, it can obtain a good solution in a short time for large-scale jobshop scheduling problems. 展开更多
关键词 job shop scheduling problem bottleneck shifting bottleneck procedure.
下载PDF
Bottlenecks and Countermeasures of High-Penetration Renewable Energy Development in China 被引量:9
10
作者 Jizhen Liu Qinghua Wang +1 位作者 Ziqiu Song Fang Fang 《Engineering》 SCIE EI 2021年第11期1611-1622,共12页
China has become the world’s largest producer and consumer of energy,and ranks first in its wind and solar power installation capacity.However,serious wind and solar curtailment in China has significantly hindered th... China has become the world’s largest producer and consumer of energy,and ranks first in its wind and solar power installation capacity.However,serious wind and solar curtailment in China has significantly hindered the development and utilization of renewable energy.To address problems in the consumption of renewable energy,this paper analyzes four key factors affecting the capacity of power generated from renewable energy sources:power balance,power regulation performance,transmission capacity,and load level.Focusing on these bottlenecks,we propose seven solutions:centralized and distributed development of renewable energy,improving the peak-load regulation flexibility of thermal power,increasing the proportion of gas turbines and pumped-hydropower storage,construction of transmission channels and a flexible smart grid developing demand response and virtual power plants,adopting new energy active support and energy storage,and establishing appropriate policies and market mechanisms.The Chinese Government and energy authorities have issued a series of policies and measures,and in the past three years,China has had remarkable achievements in the adoption of renewable energy.The rate of idle wind capacity decreased from 17%in 2016 to 7%in 2018,and that of solar decreased from 10%in 2016 to 3%in 2018. 展开更多
关键词 bottleneckS COUNTERMEASURES Idle wind and solar power Renewable energy
下载PDF
A CAPACITY EXPANSION PROBLEM WITH BUDGET CONSTRAINT AND BOTTLENECK LIMITATION 被引量:4
11
作者 杨超 刘静林 《Acta Mathematica Scientia》 SCIE CSCD 2001年第3期428-432,共5页
This paper considers a capacity expansion problem with budget constraint. Suppose each edge in the network has two attributes: capacity and the degree of difficulty. The difficulty degree of a tree T is the maximum. d... This paper considers a capacity expansion problem with budget constraint. Suppose each edge in the network has two attributes: capacity and the degree of difficulty. The difficulty degree of a tree T is the maximum. degree of difficulty of all edges in the tree and the cost for coping with the difficulty in a tree is a nondecreasing function about the difficulty degree of the tree. The authors need to increase capacities of some edges so that there is a spanning tree whose capacity can be increased to the maximum extent, meanwhile the total cost for increasing capacity as well as overcoming the difficulty in the spanning tree does not exceed a given budget D*. Suppose the cost for increasing capacity on each edge is a linear function about the increment of capacity, they transform this problem into solving some hybrid parametric spanning tree problems([1]) and propose a strongly polynomial algorithm. 展开更多
关键词 capacity expansion minimum spanning tree bottleneck spanning tree polynomial complexity
下载PDF
Bottleneck算法的改进与仿真
12
作者 徐琛 蒋珉 柴干 《计算机技术与发展》 2009年第10期37-39,43,共4页
分析了Bottleneck算法的不足,指出在路段较为拥挤的情况下该算法中因不具备预测机制而产生的时滞会引起控制误差以及主线拥挤时会造成交通流大幅波动等,产生不足的原因是算法的两个限制条件过于严格,进而提出了改进方案。改进算法中对... 分析了Bottleneck算法的不足,指出在路段较为拥挤的情况下该算法中因不具备预测机制而产生的时滞会引起控制误差以及主线拥挤时会造成交通流大幅波动等,产生不足的原因是算法的两个限制条件过于严格,进而提出了改进方案。改进算法中对两个限制条件适当放宽,在此基础上以宁杭高速(江苏段)一期为背景进行了仿真,并与原算法进行了比较。仿真结果表明,改进后的算法能更快更平稳地使交通流达到稳定状态,且具有较强的鲁棒性。 展开更多
关键词 bottleneck算法 协调控制 拥堵
下载PDF
Mine production index(MPI)-extension of OEE for bottleneck detection in mining 被引量:2
13
作者 Amol Arun Lanke Seyed Hadi Hoseinie Behzad Ghodrati 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期753-760,共8页
Although mining production depends on various equipments, significant amount of production loss can be attributed a specific equipment or fleet. Bottleneck is defined not only by production loss but also by our satisf... Although mining production depends on various equipments, significant amount of production loss can be attributed a specific equipment or fleet. Bottleneck is defined not only by production loss but also by our satisfaction from the equipment. The user satisfaction could be measured as machine effectiveness.Mining literatures on performance improvement and optimization of equipment operations assert importance of availability, utilization and production performance as key parameters. These three parameters are useful for evaluating effectiveness of equipment. Mine production index(MPI), which can represent the effect of these factors, has been applied for continuous operation in mining. MPI uses Fuzzy Delphi Analytical Hierarchy Process to determine importance of each three parameter for individual equipment. A case study in a Swedish open pit mine was done to evaluate the field application of MPI.The results reveal that crusher is the bottleneck equipment in studied mine. As a methodical approach,an algorithm which uses MPI and detects bottleneck in continuous mining operation has been proposed. 展开更多
关键词 Mine production index bottleneck seeking FDAHP Production analysis
下载PDF
Bottleneck effects on the bidirectional crowd dynamics 被引量:1
14
作者 杨晓霞 董海荣 +1 位作者 姚秀明 孙绪彬 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第12期561-571,共11页
The bottleneck effect on bidirectional crowd dynamics is of great theoretical and practical significance, especially for the designing of corridors in public places, such as subway stations or airports. Based on the f... The bottleneck effect on bidirectional crowd dynamics is of great theoretical and practical significance, especially for the designing of corridors in public places, such as subway stations or airports. Based on the famous social force model, this paper investigates the bottleneck effects on the free flow dynamics and breakdown phenomenon under different scenarios, in which different corridor shapes and inflow ratios are considered simultaneously. Numerical simulation finds an interesting self-organization phenomenon in the bidirectional flow, a typical characteristic of such a phenomenon is called lane formation, and the existence of which is independent of the corridor's shape and inflow rate. However, the pattern of the lane formed by pedestrian flow is related to the corridor's shape, and the free flow efficiency has close relationship with the inflow rate. Specifically, breakdown phenomenon occurs when inflows from both sides of the corridor are large enough, which mostly originates from the bottleneck and then gradually spreads to the other regions. Simulation results further indicate that the leaving efficiency becomes low as breakdown occurs, and the degree of congestion is proportional to the magnitude of inflow. The findings presented in this paper match well with some of our daily observations, hence it is possible to use them to provide us with theoretical suggestions in design of infrastructures. 展开更多
关键词 bidirectional pedestrian flow social force model pedestrian behavior bottleneck
下载PDF
Bottleneck Identification and Prediction of Wafer Fabrication Systems in Transient States 被引量:1
15
作者 周炳海 殷萌 孙超 《Journal of Donghua University(English Edition)》 EI CAS 2015年第4期549-553,558,共6页
According to theory of constraints( TOCs), the performance of a complex manufacturing system,such as a wafer fabrication system,is mainly determined by its bottleneck machine.A method of the identification and predict... According to theory of constraints( TOCs), the performance of a complex manufacturing system,such as a wafer fabrication system,is mainly determined by its bottleneck machine.A method of the identification and prediction of the bottleneck machine was proposed in transient states of a system. Firstly,the bottleneck index was formulated based on the workloads and the variability in wafer fabrication systems. Secondly, main factors causing the variability and their influences on the bottleneck machine in transient states of the system were analyzed and discussed. An effective bottleneck identification and prediction model was presented,which incorporated the variability and queuing theory,and took machine breakdowns and setups into considerations.Finally,the proposed bottleneck prediction method was verified by simulation experiments. Results indicate that the proposed bottleneck prediction method is feasible and effective. 展开更多
关键词 WAFER fabrications TRANSIENT STATES bottleneck PREDICTION
下载PDF
Self-organized phenomena of pedestrian counterflow through a wide bottleneck in a channel 被引量:2
16
作者 董力耘 蓝冬恺 李翔 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期591-597,共7页
The pedestrian counterflow through a bottleneck in a channel shows a variety of flow patterns due to self-organization.In order to reveal the underlying mechanism,a cellular automaton model was proposed by incorporati... The pedestrian counterflow through a bottleneck in a channel shows a variety of flow patterns due to self-organization.In order to reveal the underlying mechanism,a cellular automaton model was proposed by incorporating the floor field and the view field which reflects the global information of the studied area and local interactions with others.The presented model can well reproduce typical collective behaviors,such as lane formation.Numerical simulations were performed in the case of a wide bottleneck and typical flow patterns at different density ranges were identified as rarefied flow,laminar flow,interrupted bidirectional flow,oscillatory flow,intermittent flow,and choked flow.The effects of several parameters,such as the size of view field and the width of opening,on the bottleneck flow are also analyzed in detail.The view field plays a vital role in reproducing self-organized phenomena of pedestrian.Numerical results showed that the presented model can capture key characteristics of bottleneck flows. 展开更多
关键词 counterflow bottleneck cellular automaton flow patterns
下载PDF
一种推广的Bottleneck问题的Threshold算法
17
作者 唐松生 王晓宏 《青岛化工学院学报(自然科学版)》 1999年第1期90-92,共3页
讨论了一种推广的Botleneck问题,并给出了求问题的最优解的一个Threshold算法,并求解了一个数值例子。
关键词 Threshold算法 bottleneck 瓶颈问题
下载PDF
Review and Evaluation on the Sociocultural Theory and Bottleneck Hypothesis 被引量:1
18
作者 Fan Xu 《Review of Educational Theory》 2020年第4期58-63,共6页
Over the past three decades,a growing number of different theories in second language acquisition field have come out in an effort to provide explanations as to how language learning takes place,to figure out what var... Over the past three decades,a growing number of different theories in second language acquisition field have come out in an effort to provide explanations as to how language learning takes place,to figure out what variables are effective for second language acquisition as well as to offer guidance to mass second language learners and language teachers.Because behind every teaching approach exists certain kind of theory of language acquisition and good theory in turn can help students master language skills in an effective and efficient way.Each theory is considered to have contributed to the field by highlighting a specific aspect of the language acquisition process.Second language acquisition theories are intrinsically related with various disciplines such as applied linguistics,psychology,education,sociolinguistics,neurology,etc.Considering the impossibility to elaborate all second language theories,I will focus on sociocultural theory and bottleneck hypothesis in second language acquisition.There is an overview which follows the introduction to the Sociocultural Theory and Bottleneck Hypothesis and its contribution to second language acquisition respectively,and then I will evaluate them to see their contributions to the SLA disciplinary development. 展开更多
关键词 Sociocultural theory bottleneck hypothesis Theory evaluation
下载PDF
一种带不等式约束的Bottleneck问题的Primal算法
19
作者 唐松生 《青岛化工学院学报(自然科学版)》 1998年第4期384-386,共3页
讨论了一种带不等式约束的Botleneck问题,给出了其最优解的一个充分必要条件及求问题最优解的一个Primal算法,并给出了一个数值例子。
关键词 最优解 Primal算法 可行解 bottleneck问题
下载PDF
Influence of bottleneck on single-file pedestrian flow:Findings from two experiments
20
作者 金诚杰 姜锐 李大韦 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第8期564-571,共8页
In order to investigate the influence of bottleneck on single-file pedestrian flow,we conduct two different bottleneck experiments.The first one is on ring road,while the second one is on straight route.For the first ... In order to investigate the influence of bottleneck on single-file pedestrian flow,we conduct two different bottleneck experiments.The first one is on ring road,while the second one is on straight route.For the first one,the global density is always set to be 1.5 ped/m.The corresponding critical flow rate for the bottleneck activation is about 0.57 ped/s.The data of the detectors set at different locations,including the velocities and time-headways,show that the amplitude of the oscillation of the stop-and-go waves gradually increases during the upstream propagation.Besides,when the measured flow rates are the same,the different situations in the single-file experiments with and without bottleneck are compared and discussed.For the second one,lower flow rates are used and the bottleneck is always activated.In all the runs,the system can reach one stable state,and the time needed is nearly the same.Inside the stable area,the statistics of pedestrians'velocities keeps nearly constant in both time and space.Outside this area,when the waiting time is not long(X=10 s),the phenomenon observed is similar to that found on ring road,e.g.,the statistics of pedestrians'velocities also gradually increases during the upstream propagation.This phenomenon is similar to that found in vehicular traffic flow,which shows the universality of different traffic flows.But when the waiting time becomes longer(X=20 s),this situation will be broken since the actions of many pedestrians become much slower.All these results can facilitate understanding more about the influence of bottleneck on single-file pedestrian flow. 展开更多
关键词 pedestrian flow single-file flow EXPERIMENT bottleneck stop-and-go
下载PDF
上一页 1 2 7 下一页 到第
使用帮助 返回顶部