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“N-Two-N”教学模式的构建及在本科有机化学教学中的探究实践 被引量:1
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作者 李万梅 欧阳娅妮 章鹏飞 《大学化学》 CAS 2023年第11期54-63,共10页
基于立德树人的核心目标,探索了本科有机化学教学的新思路,从提高教师引导作用、提升学生自主学习能力、优化评价考核方式等方面进行了探索与研究。本研究以CDIO-BOPPPS协同教学模式为指导思想,引入CDIO理念创新教学设计构思,借鉴BOPPP... 基于立德树人的核心目标,探索了本科有机化学教学的新思路,从提高教师引导作用、提升学生自主学习能力、优化评价考核方式等方面进行了探索与研究。本研究以CDIO-BOPPPS协同教学模式为指导思想,引入CDIO理念创新教学设计构思,借鉴BOPPPS模式改革教学过程,结合多种教学法和多种评价方式,构建一个“N-Two-N”一体化的课堂教学体系。本文阐述了“N-Two-N”一体化模式的落实过程以及该教学模式的优点和取得的成效。 展开更多
关键词 “N-two-N”模式 CDIO-BOPPPS协同教学 立德树人 教学方法 有机化学
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Numerical Simulation for Two-Phase Water Hammer Flows in Pipe by Quasi-Two-Dimensional Model 被引量:2
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作者 Tae Uk Jang Yuebin Wu +1 位作者 Ying Xu Qiang Sun 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第2期9-15,共7页
The features of a quasi-two-dimensional( quasi-2D) model for simulating two-phase water hammer flows with vaporous cavity in a pipe are investigated. The quasi-2D model with discrete vaporous cavity in the pipe is pro... The features of a quasi-two-dimensional( quasi-2D) model for simulating two-phase water hammer flows with vaporous cavity in a pipe are investigated. The quasi-2D model with discrete vaporous cavity in the pipe is proposed in this paper. This model uses the quasi-2D model for pure liquid zone and one-dimensional( 1D) discrete vapor cavity model for vaporous cavity zone. The quasi-2D model solves two-dimensional equations for both axial and radial velocities and 1D equations for both pressure head and discharge by the method of characteristics. The 1D discrete vapor cavity model is used to simulate the vaporous cavity occurred when the pressure in the local pipe is lower than the vapor pressure of the liquid. The proposed model is used to simulate two-phase water flows caused by the rapid downstream valve closure in a reservoir-pipe-valve system.The results obtained by the proposed model are compared with those by the corresponding 1D model and the experimental ones provided by the literature,respectively. The comparison shows that the maximum pressure heads simulated by the proposed model are more accurate than those by the corresponding 1D model. 展开更多
关键词 water HAMMER method of characteristics QUASI -two -dimensional MODEL COLUMN separation discrete vapor cavity MODEL
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Construction and Analysis of Structured Preconditioners for Block Two-by-Two Matrices 被引量:8
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作者 白中治 《Journal of Shanghai University(English Edition)》 CAS 2004年第4期397-405,共9页
For the large sparse block two-by-two real nonsingular matrices, we establish a general framework of structured preconditioners through matrix transformation and matrix approximations. For the specific versions such a... For the large sparse block two-by-two real nonsingular matrices, we establish a general framework of structured preconditioners through matrix transformation and matrix approximations. For the specific versions such as modified block Jacobi-type, modified block Gauss-Seidel-type, and modified block unsymmetric (symmetric) Gauss-Seidel-type preconditioners, we precisely describe their concrete expressions and deliberately analyze eigenvalue distributions and positive definiteness of the preconditioned matrices. Also, we show that when these structured preconditioners are employed to precondition the Krylov subspace methods such as GMRES and restarted GMRES, fast and effective iteration solvers can be obtained for the large sparse systems of linear equations with block two-by-two coefficient matrices. In particular, these structured preconditioners can lead to high-quality preconditioning matrices for some typical matrices from the real-world applications. 展开更多
关键词 block two-by-two matrix PRECONDITIONER modified block relaxation iteration eigenvalue distribution positive definiteness.
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基于密度估计和VGG-Two的大豆籽粒快速计数方法 被引量:1
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作者 王莹 李越 +2 位作者 武婷婷 孙石 王敏娟 《智慧农业(中英文)》 2021年第4期111-122,共12页
为快速准确计数大豆籽粒,提高大豆考种速度和育种水平,本研究提出了一种基于密度估计和VGG-Two(VGG-T)的大豆籽粒计数方法。首先针对大豆籽粒计数领域可用图像数据集缺乏的问题,提出了基于数字图像处理技术的预标注和人工修正标注相结... 为快速准确计数大豆籽粒,提高大豆考种速度和育种水平,本研究提出了一种基于密度估计和VGG-Two(VGG-T)的大豆籽粒计数方法。首先针对大豆籽粒计数领域可用图像数据集缺乏的问题,提出了基于数字图像处理技术的预标注和人工修正标注相结合的快速目标点标注方法,加快建立带标注的公开可用大豆籽粒图像数据集。其次构建了适用于籽粒图像数据集的VGG-T网络计数模型,该模型基于VGG16,结合密度估计方法,实现从单一视角大豆籽粒图像中准确计数籽粒。最后采用自制的大豆籽粒数据集对VGG-T模型进行测试,分别对有无数据增强的计数准确性、不同网络的计数性能以及不同测试集的计数准确性进行了对比试验。试验结果表明,快速目标点标注方法标注37,563个大豆籽粒只需花费197 min,比普通人工标注节约了1592 min,减少约96%的人工工作量,大幅降低时间成本和人工成本;采用VGG-T模型计数,其评估指标在原图和补丁(patch)情况下的平均绝对误差分别为0.6和0.2,均方误差为0.6和0.3,准确性高于传统图像形态学操作以及ResNet18、ResNet18-T和VGG16网络。在包含不同密度大豆籽粒的测试集中,误差波动较小,仍具有优良的计数性能,同时与人工计数和数粒仪相比,计数11,350个大豆籽粒分别节省大约2.493 h和0.203 h,实现大豆籽粒的快速计数任务。 展开更多
关键词 卷积神经网络 籽粒计数 籽粒图像 点标注 密度图 VGG-two 育种
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临床废弃机用M-two镍钛锉的损伤分析 被引量:4
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作者 张平虎 屈铁军 倪龙兴 《牙体牙髓牙周病学杂志》 CAS 2016年第3期175-179,共5页
目的:探讨M-two镍钛锉在根管治疗中的损伤、断裂机制。方法:从临床收集近6个月内906支废弃的机用M-two镍钛锉,体视显微镜观察损伤情况,并且对断锉进行微距数码摄影,同时运用ImagePro Plus软件对断点位置进行测量。采用SPSS 17.0软件包... 目的:探讨M-two镍钛锉在根管治疗中的损伤、断裂机制。方法:从临床收集近6个月内906支废弃的机用M-two镍钛锉,体视显微镜观察损伤情况,并且对断锉进行微距数码摄影,同时运用ImagePro Plus软件对断点位置进行测量。采用SPSS 17.0软件包对数据进行统计学分析。结果:906支M-two镍钛锉中,有196支锉刃发生塑性形变(21.6%);221支锉发生断裂(24.4%)。#10.04锉器械分离率最高(39.3%),#15.05次之(33.6%)。#30.05锉的断裂位点最高(3.65±0.80)mm。折断的类型主要包括:弯曲疲劳折断(65.2%)和扭转折断(34.8%)。结论:#10.04和#15.05锉塑性形变占有较高比例,因此建议一次性使用;其余锉建议临床降低使用次数,并且定期更换。 展开更多
关键词 器械分离 M-two镍钛锉 疲劳失效
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Screening of hepatocyte proteins binding to NS5ABP37 protein by yeast-two hybrid system 被引量:1
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作者 Lei Zhang1,Qing-yong Ma1,Xian-kui Meng1,Kang Li1,Jun Cheng21.The First Affiliated Hospital,Medical School of Xi’an Jiaotong University,Xi’an 710061 2.Institute of Infectious Diseases,Beijing Ditan Hospital,Beijing 100011,China 《Journal of Pharmaceutical Analysis》 SCIE CAS 2009年第4期234-237,251,共5页
Objective To investigate the biological function of NS5ABP37 and to look for proteins interacting with NS5ABP37 protein in hepatocytes.Methods We constructed bait plasmid expressing NS5ABP37 protein of hepatitis C vir... Objective To investigate the biological function of NS5ABP37 and to look for proteins interacting with NS5ABP37 protein in hepatocytes.Methods We constructed bait plasmid expressing NS5ABP37 protein of hepatitis C virus(HCV)by cloning the gene of NS5ABP37 protein into pGBKT7,then the recombinant plasmid DNA was transformed into yeast AH109(α type).The transformed yeast AH109 was mated with yeast Y187(α type)containing liver cDNA library plasmid in 2×YPDA medium.Diploid yeast was plated on synthetic dropout nutrient medium(SD/-Trp-Leu-His-Ade)containing X-α-gal for selection and screening.After extracting and sequencing of plasmids from positive(blue)colonies,we made a sequence analysis by bioinformatics.Results We screened twenty-five proteins binding to NS5ABP37,including Homo sapiens cyclin I(CCNI)gene,Homo sapiens matrix metallopeptidase 25(MMP25)and Homo sapiens talin 1.Conclusion The yeast-two hybrid system is an effective method for identifying hepatocyte proteins interacting with NS5ABP37 of HCV.And the biological function of NS5ABP37 may be associated with glycometabolism,lipid metabolism and apoptosis. 展开更多
关键词 NS5ABP37 yeast-two hybrid system hepatitis C virus(HCV)
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Codimension-two bifurcation of axial loaded beam bridge subjected to an infinite series of moving loads 被引量:1
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作者 杨新伟 田瑞兰 李海涛 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期121-126,共6页
A novel model is proposed which comprises of a beam bridge subjected to an axial load and an infinite series of moving loads. The moving loads, whose distance between the neighbouring ones is the length of the beam br... A novel model is proposed which comprises of a beam bridge subjected to an axial load and an infinite series of moving loads. The moving loads, whose distance between the neighbouring ones is the length of the beam bridge, coupled with the axial force can lead the vibration of the beam bridge to codimension-two bifurcation. Of particular concern is a parameter regime where non-persistence set regions undergo a transition to persistence regions. The boundary of each stripe represents a bifurcation which can drive the system off a kind of dynamics and jump to another one, causing damage due to the resulting amplitude jumps. The Galerkin method, averaging method, invertible linear transformation, and near identity nonlinear transformations are used to obtain the universal unfolding for the codimension-two bifurcation of the mid-span deflection. The efficiency of the theoretical analysis obtained in this paper is verified via numerical simulations. 展开更多
关键词 mid-span deflection beam bridge infinite series of moving loads codimension-two bifurcation
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The Influence Function of the Correlation Indexes in a Two-by-Two Table
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作者 Giovanni Girone Fabio Manca Claudia Marin 《Applied Mathematics》 2014年第21期3411-3420,共10页
In this paper we examine 5 indexes (the two Yule’s indexes, the chi square, the odds ratio and an elementary index) of a two-by-two table, which estimate the correlation coefficient ρ in a bivariate Bernoulli distri... In this paper we examine 5 indexes (the two Yule’s indexes, the chi square, the odds ratio and an elementary index) of a two-by-two table, which estimate the correlation coefficient ρ in a bivariate Bernoulli distribution. We will find the compact expression of the influence functions, which allow the quantification of the effect of an infinitesimal contamination of the probability of any pair of attributes of the bivariate random variable distributed according to the above-mentioned model. We prove that the only unbiased index is the chi square. In order to determine the indexes, which are less sensitive to contamination, we obtain the expressions of three synthetic measures of the influence function, which are the maximum contamination (gross sensitivity error), the mean square deviation and the variance. These results, even if don’t allow a definitive assessment of the overall optimum properties of the five indexes, as not all of them are unbiased, nevertheless they allow to appreciating the synthetic entity of the effect of the contaminations in the estimation of the parameter ρ of the bivariate Bernoulli distribution. 展开更多
关键词 Two-by-two TABLE Influence FUNCTION Correlation Indexes GROSS Sensitivity Error Mean Square Deviation Asymptotic Variance
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Suboptimal stochastic H-two/H-infinity design with spectrum constraint
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作者 Zhongwei LIN Weihai ZHANG Yan LIN 《控制理论与应用(英文版)》 EI 2008年第3期317-321,共5页
This paper studies the problem of suboptimal state-feedback H-two/H-infinity control of stochastic systems with spectrum constraint. Concretely speaking, a mixed suboptimal H-two/H-infinity controller synthesis togeth... This paper studies the problem of suboptimal state-feedback H-two/H-infinity control of stochastic systems with spectrum constraint. Concretely speaking, a mixed suboptimal H-two/H-infinity controller synthesis together with placing the spectrum into a strip region is considered, which is achieved via solving a convex optimization problem. 展开更多
关键词 Stochastic stabilization Suboptimal H-two/H-infinity control Spectrum assignment Linear matrix inequality (LMI)
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Properties of ground state and anomalous quantum fluctuations in one-dimensional polaron-soliton systems-the effects of electron-two-phonon interaction and non-adiabatic quantum correlations
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作者 罗质华 曹锡金 余超凡 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期372-383,共12页
Based on the Holstein model Hamiltonian of one-dimensional molecular crystals, by making use of the expansion approach of the correlated squeezed-coherent states of phonon instead of the two-phonon coherent state expa... Based on the Holstein model Hamiltonian of one-dimensional molecular crystals, by making use of the expansion approach of the correlated squeezed-coherent states of phonon instead of the two-phonon coherent state expansion scheme, the properties of the ground state and the anomalous quantum fluctuations are investigated in a strongly coupled electron-phonon system with special consideration of the electron-two-phonon interaction. The effective renormalization (ai) of the displacement of the squeezed phonons with the effect of the squeezed-coherent states of phonon and both the electron-displaced pbonon and the polaron-squeezed phonon correlations have been combined to obtain the anomalous quantum fluctuations for the corrections of the coherent state. Due to these non-adiabatic correlations, the effective displacement parameter ai is larger than the ordinary parameter ai (0) In comparison with the electron-one-phonon interaction (g) corrected as oig, we have found the electron-two-phonon interaction (gl) corrected as ai2gi is enhanced significantly. For this reason, the ground state energy (E(2)) contributed by the electron-two-phonon interaction is more negative than the single-phonon case (E01)) and the soliton solution is more stable. At the same time, the effects of the electron-two-phonon interaction greatly increase the polaron energy and the quantum fluctuations. Furthermore, in a deeper level, we have considered the effect of the polaron-squeezed phonon correlation (f-correlation). Since this correlation parameter f 〉 1, this effect will strengthen the electron-one and two-phonon interactions by fai9 and f2ai2g1, respectively. The final results show that the ground state energy and the polaron energy will appear more negative further and the quantum fluctuations will gain further improvement. 展开更多
关键词 correlated squeezed-coherent state expansion electron-two-phonon interaction nonadiabatic correlations and renormalized phonon displacement anomalous quantum fluctuations polaron-squeezed phonon correlation
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The Pancharatnam Phase of a Three-Level Atom Coupled to Two Systems of N-Two Level Atoms
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作者 D. A. M. Abo-Kahla 《Journal of Quantum Information Science》 2016年第1期44-55,共12页
In this paper, we present the analytical solution for the model that describes the interaction between a three-level atom and two systems of N-two level atoms. The effects of the quantum numbers and the coupling param... In this paper, we present the analytical solution for the model that describes the interaction between a three-level atom and two systems of N-two level atoms. The effects of the quantum numbers and the coupling parameters between spins on the Pancharatnam phase and the atomic inversion, for some special cases of the initial states, are investigated. The comparison between the two effects shows that the analytic results are well consistent. 展开更多
关键词 Pancharatnam Phase Atomic Inversion Systems of N-two Level Atoms
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Observation on the Efficacy of One-Knot-Two-Wire Suture Bridge Method Technique in Treating Small and Medium-Sized Rotator Cuff Tears
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作者 Chaoqi Pang Songlin Liu Liang Ma 《Open Journal of Orthopedics》 2024年第12期562-570,共9页
Objective: To explore the clinical efficacy of shoulder arthroscopic one-knot-two-wire suture bridge technique in the treatment of small and medium-sized rotator cuff tears. Methods: The clinical data of 22 patients w... Objective: To explore the clinical efficacy of shoulder arthroscopic one-knot-two-wire suture bridge technique in the treatment of small and medium-sized rotator cuff tears. Methods: The clinical data of 22 patients with small and medium-sized rotator cuff injuries treated with the one-knot-two-wire suture bridge technique from February 2022 to June 2023 in the Department of Orthopaedics of Jingzhou Hospital Affiliated to Yangtze University were retrospectively analysed, among which 14 cases were male and 8 cases were female;the age ranged from 35 to 68 years old, with an average of (50.86 ± 10.80) years old. All cases underwent an MRI examination of the shoulder joint to understand the type and degree of injury. The duration of the disease ranged from 120 to 166 d, with a mean of (141.23 ± 13.46) d. The evaluation of the operation time, intraoperative bleeding, visual analogue scale (VAS) of pain, Constant-Murley score and Sugaya grading of shoulder MRI were performed at the last follow-up. Results: All 22 patients were followed up for 12 - 18 months, with a mean of (14.68 ± 1.89 d). The operation time was 38 - 58 min, mean (48.18 ± 5.92) min;intraoperative bleeding was 5 - 15 mL, mean (10.00 ± 3.45) mL. All patients achieved normal healing without re-tear, vascular and nerve injury, incision infection, anchor nail loosening and dislodgement and other complications. At the last follow-up, both shoulders were normal in shape and symmetrical on both sides. The VAS score was 0 - 1.2 points, with an average of 0.61 ± 0.42 points, and the Constant-Murley score was 70 - 98 points, with an average of 86.09 ± 8.56 points. The Sugaya classification of MRI examination was 17 cases of grade I, 4 cases of grade II, and 1 case of grade III. Conclusion: One-knot-two-wire suture bridge technique is used for the treatment of small and medium-sized rotator cuff tears with short operative time, low bleeding, and good clinical outcome. 展开更多
关键词 One-Knot-two-Wire Bridge Method Rotator Cuff Tear Shoulder Arthroscopy Suture Bridge
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Double Fire-Two Stage Method and Parameter Calculation of Underground Coal Gasification
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作者 杨兰和 梁杰 余力 《International Journal of Mining Science and Technology》 SCIE EI 2000年第2期11-14,共4页
The double fire two stage method of underground coal gasification was suggested. On the basis of material balance, the ideal gasification parameters were calculated, and the field test process was briefly introduced. ... The double fire two stage method of underground coal gasification was suggested. On the basis of material balance, the ideal gasification parameters were calculated, and the field test process was briefly introduced. In addition, the cause for a middle to a high heat value of water gas was described. And the reasonableness and feasiblity of the method was proved, showing that the double fire two stage gasification is an important technique for commercialized production. 展开更多
关键词 DOUBLE FIRE sources two STAGE UNDERGROUND COAL GASIFICATION UNDERGROUND water gas
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Photon number cumulant expansion and generating function for photon added-and subtracted-two-mode squeezed states
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作者 卢道明 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期70-73,共4页
For the first time, we derive the photon number cumulant for two-mode squeezed state and show that its cumulant expansion leads to normalization of two-mode photon subtracted-squeezed states and photon added- squeezed... For the first time, we derive the photon number cumulant for two-mode squeezed state and show that its cumulant expansion leads to normalization of two-mode photon subtracted-squeezed states and photon added- squeezed states. We show that the normalization is related to Jacobi polynomial, so the cumulant expansion in turn represents the new generating function of Jacobi polynomial. 展开更多
关键词 Jacobi polynomial photon number cumulant expansion photon subtracted- and photon added- two-mode squeezed states
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Estimation of Area under Receiver Operating Characteristic Curve for Bi-Pareto and Bi-Two Parameter Exponential Models
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作者 Bhavna Kaushal Kanchan Jain Suresh K. Sharma 《Open Journal of Statistics》 2014年第1期1-10,共10页
In this paper, we find the ROC curves for Bi-Pareto and Bi-two parameter exponential distributions. Theoretical, parametric and non-parametric values of area under receiver operating characteristic (AUROC) curve for d... In this paper, we find the ROC curves for Bi-Pareto and Bi-two parameter exponential distributions. Theoretical, parametric and non-parametric values of area under receiver operating characteristic (AUROC) curve for different parametric combinations have been calculated using simulations. These values are compared in terms of root mean square and mean absolute errors. The results are demonstrated for two real data sets. 展开更多
关键词 ROC AUROC PARETO TWO PARAMETER Exponential Root Mean Square ERROR Mean Absolute ERROR
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农林高校“一体两翼”专业学位硕士研究生产教综合体建设与实践
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作者 姚立健 赵超 +1 位作者 徐丽君 孙通 《中国农机化学报》 北大核心 2026年第1期339-345,共7页
针对当前产教协同育人过程中存在融合深度不足、发力点不明晰的困境,提出一种“一体两翼”专业学位硕士研究生产教综合体建设方案。通过产教双方共建“校中企”和“企中校”,对传统实践基地进行形式延伸和内涵拓展;将三全育人、党建+、... 针对当前产教协同育人过程中存在融合深度不足、发力点不明晰的困境,提出一种“一体两翼”专业学位硕士研究生产教综合体建设方案。通过产教双方共建“校中企”和“企中校”,对传统实践基地进行形式延伸和内涵拓展;将三全育人、党建+、产业文化贯穿于实践基地建设,塑造研究生的家国情怀、专业志趣,激发他们投身产业、服务“三农”的理想抱负,进而解决实习生留任率不高、学农不爱农的问题。联合一二三产业中的一批农机企业组建实践基地集群,为学生提供内容丰富、形式多样的实践科目,形成稳定的实践基地“生态圈”。通过全员参与建设的实践类课程,设计覆盖全过程的实践科目等手段来推动研究生的全方位发展。成果可为研究生实践基地的建设及长效运行提供新思路。 展开更多
关键词 三全育人 产教融合 一体两翼 产教综合体 三产融合
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基于双层模糊控制与改进遗传算法的移动机器人路径规划算法
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作者 田敏 吴晓枫 《计算机应用研究》 北大核心 2026年第1期183-190,共8页
为提升移动机器人在复杂道路环境下执行多任务时的路径安全性与规划效率,提出了一种结合双层模糊控制系统和改进遗传算法的方法,以应对移动机器人路径规划中复杂道路环境与多元化任务安全性的挑战。该方法首先构建了一个基于专家系统的... 为提升移动机器人在复杂道路环境下执行多任务时的路径安全性与规划效率,提出了一种结合双层模糊控制系统和改进遗传算法的方法,以应对移动机器人路径规划中复杂道路环境与多元化任务安全性的挑战。该方法首先构建了一个基于专家系统的双层模糊控制系统:第一层将复杂路况和障碍物转换为道路安全度等级,第二层结合任务安全等级生成遗传算法的适应度权重。通过引入道路安全因素优化遗传算法的适应度函数模型,增强路径规划的安全性。算法实现上,采用伯努利混沌映射、Gaussian算子和Symmetrical Sigmoid算子优化选择、交叉、变异操作,提升了全局搜索能力和效率。实验表明,该方法相较于其他算法,路径距离最大减少5.9%,转弯次数最大减少85.7%,且在多种对比实验中表现出优异的普适性和鲁棒性,有效解决了复杂道路环境与任务安全需求之间的关系。 展开更多
关键词 改进遗传算法 路径规划 双层模糊控制系统 移动机器人
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基于分块策略的二维装箱问题求解
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作者 赵向领 苏坛杰 +2 位作者 秦雪 李朝阳 陈晓刚 《包装工程》 北大核心 2026年第1期111-121,共11页
目的提升条带型容器二维装箱问题的空间利用率和算法效率,支持物流、制造等复杂装载场景下的资源优化。方法提出基于分块和分层叠加的两阶段优化算法。第1阶段为分块策略,以最小分块数量和最大所有分块长度之和为目标,依据条带型容器长... 目的提升条带型容器二维装箱问题的空间利用率和算法效率,支持物流、制造等复杂装载场景下的资源优化。方法提出基于分块和分层叠加的两阶段优化算法。第1阶段为分块策略,以最小分块数量和最大所有分块长度之和为目标,依据条带型容器长度,把容器分割成多块,并关联每块与某一待装物品的长度。第2阶段为单块组装策略,引入动态分层叠加机制,建立单块组装算法。结果采用17组经典Benchmark数据,与自适应分块策略、Gurobi求解器进行对比,所提算法的平均求解时间仅为0.10s,自适应分块策略需要0.97s,Gurobi需要1285.15s;所提算法的面积利用率为85.06%,自适应分块策略为72.96%,Gurobi为72.91%,可见效率显著提升。该算法以0.51s的平均运行时间实现了面积利用率84.70%,标准差为0.56,优于多数对比算法。测试了5组航空货运实际案例,最多有565件货物,规划时间仅为2.81s,满足工业实时性需求。结论所提出的分块、分层叠加两阶段算法兼顾了分配效果与效率,适用于实时性和可靠性要求较高的工业应用,可为复杂物流装载优化提供有效支持。 展开更多
关键词 二维装箱问题 分块策略 面积利用率 组合优化 启发式算法
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习近平新时代中国特色社会主义思想体系总体构架的逻辑探析
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作者 陶文昭 杨建宇 《新疆师范大学学报(哲学社会科学版)》 北大核心 2026年第1期5-12,共8页
习近平新时代中国特色社会主义思想体系总体构架展现了新时代理论创新成果的全景全貌。在逻辑构架维度,以“十个明确”为内核,构建了以“明体达用,体用贯通—知行互铨,践实通变—执中秉要,守创相济—鉴往知来,史镜国是”为主要理论特点... 习近平新时代中国特色社会主义思想体系总体构架展现了新时代理论创新成果的全景全貌。在逻辑构架维度,以“十个明确”为内核,构建了以“明体达用,体用贯通—知行互铨,践实通变—执中秉要,守创相济—鉴往知来,史镜国是”为主要理论特点的四维框架,通过“两个结合”创造性转化马克思主义基本原理和中华文明基因,形成兼具理论解释力与中国特色的现代性理论构架;在历史构架维度,遵循辩证唯物主义和历史唯物主义,通过中国式现代化重构现代化理论范式。这一双重构架互动机制既推动习近平新时代中国特色社会主义思想的体系化学理化,促进马克思主义中国化时代化的发展,又以人类命运共同体理念重构全球治理范式,为发展中国家提供现代化新路径,为当代世界社会主义运动注入新动能。 展开更多
关键词 习近平新时代中国特色社会主义思想 “两个结合” 中国式现代化 体系化 学理化 总体构架
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词语江南与“重建内心”——析沈苇的诗集《诗江南》
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作者 魏庆培 《廊坊师范学院学报(社会科学版)》 2026年第1期49-59,共11页
《诗江南》是著名诗人沈苇从新疆返乡后集中抒写的一部关于江南的诗集。西域与江南两地的生活经验构成了其诗歌基本的写作动力,也为打开现代性江南的诗性世界提供了话语基础和思想支撑。返乡后的诗人,在追踪江南所表现出的种种现代性面... 《诗江南》是著名诗人沈苇从新疆返乡后集中抒写的一部关于江南的诗集。西域与江南两地的生活经验构成了其诗歌基本的写作动力,也为打开现代性江南的诗性世界提供了话语基础和思想支撑。返乡后的诗人,在追踪江南所表现出的种种现代性面孔的同时,亦对其内在的矛盾和危机进行了深刻反思。在此,诗人继续贯彻“关乎世界与人性,抵达人之为人的基本命题”,将“综合抒情”纳入“无边的现实主义”的文学视野中,通过对江南的重新发现和体认,实现了自我诗学的内在转换和文本重建。 展开更多
关键词 沈苇 《诗江南》 两个故乡 现代性江南 话语 诗性 诗学观念
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