Electronic Research Archive最新文献_第5页

New challenges in fleet deployment considering EU oil sanctions 考虑到欧盟的石油制裁，船队部署面临新的挑战

IF 0.8 4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023230

Yiwei Wu, Yao Lu, Shuaian Wang, Lu Zhen

{"title":"New challenges in fleet deployment considering EU oil sanctions","authors":"Yiwei Wu, Yao Lu, Shuaian Wang, Lu Zhen","doi":"10.3934/era.2023230","DOIUrl":"https://doi.org/10.3934/era.2023230","url":null,"abstract":"Due to European Union (EU) oil sanctions, tanker shipping companies need to redeploy their tankers by moving tankers between ship routes with the consideration of flag states of tankers, but the literature lacks quantitative methods for this problem. To fill this research gap, this paper studies an integrated problem of fleet deployment, fleet repositioning, round trip completion, and speed optimization with the consideration of flag states of tankers. The problem is formulated as a nonlinear integer programming model to minimize the total cost, including the fleet repositioning cost, the mismatch cost, and the fuel cost, during the planning period while satisfying the total crude oil transportation demand of each voyage and the minimum shipping frequency. Some linearization methods are used to transform the nonlinear model to a linear one which can be directly solved by Gurobi. The average solving time required for 17 computational instances is 4.5 minutes, which validates the effectiveness of the proposed model. Sensitivity analyses, including the influences of the unit fuel price, the total crude oil transportation demand, the mismatch cost of completing a round trip by a deployed tanker, and the repositioning cost for each deployed tanker, on operations decisions, are conducted to obtain managerial insights.","PeriodicalId":48554,"journal":{"name":"Electronic Research Archive","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70246832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical study for a class of time fractional diffusion equations using operational matrices based on Hosoya polynomial 基于细谷多项式的运算矩阵对一类时间分数扩散方程的数值研究

IF 0.8 4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023231

Ping Zhou, H. Jafari, R. Ganji, S. Narsale

引用次数: 1

Some new results for $ B_1 $-matrices 关于$ B_1 $-矩阵的一些新结果

IF 0.8 4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023244

Yan Li, Yaqiang Wang

引用次数: 0

Application of Improved Jellyfish Search algorithm in Rotate Vector reducer fault diagnosis 改进水母搜索算法在旋转矢量减速器故障诊断中的应用

IF 0.8 4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023250

Xiaoyan Wu, Guowen Ye, Yongming Liu, Zhuanzhe Zhao, Zhibo Liu, Yu Chen

{"title":"Application of Improved Jellyfish Search algorithm in Rotate Vector reducer fault diagnosis","authors":"Xiaoyan Wu, Guowen Ye, Yongming Liu, Zhuanzhe Zhao, Zhibo Liu, Yu Chen","doi":"10.3934/era.2023250","DOIUrl":"https://doi.org/10.3934/era.2023250","url":null,"abstract":"In order to overcome the low accuracy of traditional Extreme Learning Machine (ELM) network in the performance evaluation of Rotate Vector (RV) reducer, a pattern recognition model of ELM based on Ensemble Empirical Mode Decomposition (EEMD) fusion and Improved artificial Jellyfish Search (IJS) algorithm was proposed for RV reducer fault diagnosis. Firstly, it is theoretically proved that the torque transmission of RV reducer has periodicity during normal operation. The characteristics of data periodicity can be effectively reflected by using the test signal periodicity characteristics of rotating machinery and EEMD. Secondly, the Logistic chaotic mapping of population initialization in JS algorithm is replaced by tent mapping. At the same time, the competition mechanism is introduced to form a new IJS. The simulation results of standard test function show that the new algorithm has the characteristics of faster convergence and higher accuracy. The new algorithm was used to optimize the input layer weight of the ELM, and the pattern recognition model of IJS-ELM was established. The model performance was tested by XJTU-SY bearing experimental data set of Xi'an Jiaotong University. The results show that the new model is superior to JS-ELM and ELM in multi-classification performance. Finally, the new model is applied to the fault diagnosis of RV reducer. The results show that the proposed EEMD-IJS-ELM fault diagnosis model has higher accuracy and stability than other models.","PeriodicalId":48554,"journal":{"name":"Electronic Research Archive","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70247544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Elliptic and multiple-valued solutions of some higher order ordinary differential equations 若干高阶常微分方程的椭圆解和多值解

IF 0.8 4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023302

Guoqiang Dang

引用次数: 2

Multi-features combinatorial optimization for keyframe extraction 关键帧提取的多特征组合优化

IF 0.8 4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023304

Lei Ma, Weiyu Wang, Yaozong Zhang, Yu Shi, Zhenghua Huang, Hanyu Hong

{"title":"Multi-features combinatorial optimization for keyframe extraction","authors":"Lei Ma, Weiyu Wang, Yaozong Zhang, Yu Shi, Zhenghua Huang, Hanyu Hong","doi":"10.3934/era.2023304","DOIUrl":"https://doi.org/10.3934/era.2023304","url":null,"abstract":"Recent advancements in network and multimedia technologies have facilitated the distribution and sharing of digital videos over the Internet. These long videos contain very complex contents. Additionally, it is very challenging to use as few frames as possible to cover the video contents without missing too much information. There are at least two ways to describe these complex videos contents with minimal frames: the keyframes extracted from the video or the video summary. The former lays stress on covering the whole video contents as much as possible. The latter emphasizes covering the video contents of interest. As a consequence, keyframes are widely used in many areas such as video segmentation and object tracking. In this paper, we propose a keyframe extraction method based on multiple features via a novel combinatorial optimization algorithm. The key frame extraction is modeled as a combinatorial optimization problem. A fast dynamic programming algorithm based on a forward non-overlapping transfer matrix in polynomial time and a 0-1 integer linear programming algorithm based on an overlapping matrix is proposed to solve our maximization problem. In order to quantitatively evaluate our approach, a long video dataset named 'Animal world' is self-constructed, and the segmentation evaluation criterions are introduced. A good result is achieved on 'Animal world' dataset and a public available Keyframe-Sydney KFSYD dataset [1].","PeriodicalId":48554,"journal":{"name":"Electronic Research Archive","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70248035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fractional integral associated with the Schrödinger operators on variable exponent space 变指数空间上与Schrödinger算子相关的分数积分

4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023345

Huali Wang, Ping Li

引用次数: 0

Phased mission reliability analysis of unmanned ship systems 无人船系统阶段任务可靠性分析

4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023325

Xu Zhan, Yang Yong, Wang Xiao

引用次数: 0

Investigation of the global dynamics of two exponential-form difference equations systems 两个指数型差分方程组的全局动力学研究

4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023338

Merve Kara

{"title":"Investigation of the global dynamics of two exponential-form difference equations systems","authors":"Merve Kara","doi":"10.3934/era.2023338","DOIUrl":"https://doi.org/10.3934/era.2023338","url":null,"abstract":"<abstract>In this study, we investigate the boundedness, persistence of positive solutions, local and global stability of the unique positive equilibrium point and rate of convergence of positive solutions of the following difference equations systems of exponential forms: <disp-formula> <label/> <tex-math id=\"FE1\"> begin{document}$ begin{equation*} Upsilon_{n+1} = frac{Gamma_{1}+delta_{1}e^{-Psi_{n-1}}}{Theta_{1}+Psi_{n}}, Psi_{n+1} = frac{Gamma_{2}+delta_{2}e^{-Omega_{n-1}}}{Theta_{2}+Omega_{n}}, Omega_{n+1} = frac{Gamma_{3}+delta_{3}e^{-Upsilon_{n-1}}}{Theta_{3}+Upsilon_{n}}, end{equation*} $end{document} </tex-math></disp-formula> <disp-formula> <label/> <tex-math id=\"FE2\"> begin{document}$ begin{equation*} Upsilon_{n+1} = frac{Gamma_{1}+delta_{1}e^{-Psi_{n-1}}}{Theta_{1}+Upsilon_{n}}, Psi_{n+1} = frac{Gamma_{2}+delta_{2}e^{-Omega_{n-1}}}{Theta_{2}+Psi_{n}}, Omega_{n+1} = frac{Gamma_{3}+delta_{3}e^{-Upsilon_{n-1}}}{Theta_{3}+Omega_{n}}, end{equation*} $end{document} </tex-math></disp-formula> for $ nin mathbb{N}_{0} $, where the initial conditions $ Upsilon_{-j} $, $ Psi_{-j} $, $ Omega_{-j} $, for $ jin{0, 1} $ and the parameters $ Gamma_{i} $, $ delta_{i} $, $ Theta_{i} $ for $ iin{1, 2, 3} $ are positive constants.</abstract>","PeriodicalId":48554,"journal":{"name":"Electronic Research Archive","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135007466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Riccati-Bernoulli subsidiary ordinary differential equation method to the coupled Higgs field equation 耦合希格斯场方程的里卡蒂-伯努利辅助常微分方程解法

4区数学

Electronic Research Archive Pub Date : 2023-01-01 DOI: 10.3934/era.2023342

Yi Wei

引用次数: 0