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锻造车间能耗建模及优化调度研究

农业装备与车辆工程 2024年第2期62卷 130-134页

作者：杨振华陈君宝别俊陈子春湖北汽车工业学院机械工程学院湖北十堰442002

针对锻造车间能耗优化调度问题,通过建立能耗数学模型和改进NSGA2算法并对其进行实例验证且得到最优解集合。建立了一种基于机器状态-能耗分布关系的车间能耗模型,并以此模型为最小能耗目标,再加上最大完工时间和最大机器负荷最小化,共... 详细信息

针对锻造车间能耗优化调度问题,通过建立能耗数学模型和改进NSGA2算法并对其进行实例验证且得到最优解集合。建立了一种基于机器状态-能耗分布关系的车间能耗模型,并以此模型为最小能耗目标,再加上最大完工时间和最大机器负荷最小化,共同组成车间调度问题的目标函数。改进了NSGA2算法,种群初始化采用全局生成和快速生成两种方式,编码时选择了工序排列编码和机器选择编码的双层编码方式,交叉策略分别选择IPOX交叉和MPX交叉,变异时插入式变异和贪婪变异保证种群多样性并加强局部搜索能力,最后使用MATLAB对算法实例进行求解运算,得出有效非劣解集,以验证车间能耗模型和改进NSGA2算法的有效性和可行性。

关键词：车间优化调度能耗建模 NSGA2算法

沙库巴曲缬沙坦治疗慢性肾脏病5期难治性高血压患者的临床观察

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实用医学杂志 2024年第4期40卷 543-548页

作者：宁燕虹徐苑珊李晓华李仕华杨桢华廖蕴华潘玲广西医科大学第一附属医院肾内科南宁530021 南宁市第二人民医院肾内科南宁530031

目的评估沙库巴曲缬沙坦治疗慢性肾脏病(CKD)5期合并难治性高血压患者的心血管获益及安全性。方法一项真实世界的观察性研究,选取2020年9月至2022年3月广西医科大学第一附属医院诊治的CKD5期合并难治性高血压患者,分为观察组(沙库巴曲... 详细信息

目的评估沙库巴曲缬沙坦治疗慢性肾脏病(CKD)5期合并难治性高血压患者的心血管获益及安全性。方法一项真实世界的观察性研究,选取2020年9月至2022年3月广西医科大学第一附属医院诊治的CKD5期合并难治性高血压患者,分为观察组(沙库巴曲缬沙坦)和对照组(ACEI或ARB),两组患者均接受规律透析及CKD5期常规药物治疗,随访至少3个月。比较两组患者之间的基线资料、疗效及安全性指标的差异,观察不良事件发生情况。结果研究共纳入110例患者,观察组及对照组各55例。两组患者按1∶1进行倾向性评分匹配,基线资料比较提示两组之间性别、年龄、透析龄、基础病因、透析模式及血压水平差异无统计学意义(P>0.05);观察组治疗3个月后的收缩压(SBP)、舒张压(DBP)、心率、B型钠尿肽前体(pro-BNP)、心功能Ⅳ级比例较前下降,左室射血分数(LVEF)0.05)。随访期间仅对照组有1例出现高钾血症,两组均未出现低血压及其他不良反应。结论沙库巴曲缬沙坦治疗CKD5期高血压患者的心血管获益明显,在降压、改善心功能、减轻容量负荷等方面均有疗效,且不良事件少,安全性也较高。

关键词：沙库巴曲缬沙坦 CKD5期高血压疗效安全性

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涉铅洗浴洗衣污水处理研究

蓄电池 2024年第3期61卷 133-136页

作者：杨振华豆红涛宋翊申毅飞陕西凌云蓄电池有限公司陕西宝鸡721304 中国电池工业协会北京100055

经长期跟踪采样分析,明确了铅酸蓄电池生产中涉铅洗浴洗衣污水总铅含量在0.14~0.53 mg/L之间,经厌氧/好氧生化处理后可以达到《电池工业污染物排放标准》(GB 30484-2013)中规定的排放要求。

关键词：铅铅酸蓄电池洗浴洗衣污水生化处理厌氧好氧

Velocity transformation for compressible wall-bounded turbulence——An approach through the mixing length hypothesis

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 108-125页

作者： Xuke Zhu Yubin Song Xiaoshuo yang zhenhua Xia State Key Laboratory of Fluid Power and Mechatronic Systems and Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China

In an endeavor to establish a connection between the mean velocity profile in compressible wall-bounded turbulence and its incompressible analogue,a refined version of the Trettel and Larsson's(TL)transformation is systematically derived and rigorously assessed across diverse flow *** the recently proposed intrinsic compressibility effects and modeling the multi-layer structure of mixing lengths,the proposed transformation demonstrates exceptional performance in collapsing 57canonical flow cases,including cooled channel and pipe flows,channel flows with pseudo heat sources,as well as adiabatic and diabatic boundary layer ***,the transformation seamlessly extends to low Reynolds number cooled channel and pipe flows,achieving a level of accuracy unparalleled by other transformations in the current state-of-the-art.

关键词： mixing length hypothesis compressible wall-bounded turbulence velocity transformation law of the wall

Numerical simulation research on multiphase flow of aviation centrifugal pump based on OpenFOAM

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Chinese Journal of Aeronautics 2024年第4期37卷 256-275页

作者： Xianwei LIU Jiangfeng FU Junjie yang Dewen YIN zhenhua ZHOU Huacong LI College of Power and Energy Northwestern Polytechnical UniversityXi’an 710072China Norinco Group Testing and Research Institute Huayin 714200China AECC Xi’an Engine Control Technology Co.Ltd. Xi’an 710077China AECC Guizhou Honglin Aero Engine Control Technology Co.Ltd. Guiyang 550009China

This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used in the phase-change control equation for unstructured-grid multiphase flow,and due to the limitation of flow time-step in whole flow regimes,the control equation of vapor–liquid two-phase flow considering cavitation mass transport is established firstly,modifying the momentum equation by introducing the surface tension,and adding the artificial convective flow to the phase equation to solve the numerical dissipation ***,in consideration of the local time step principle and based on the multi-dimensional general limiter algorithm with explicit solutions under the OpenFOAM platform,a solution method of steady-state VOF (Volume of Fluid) model considering cavitation two-phase change is constructed,and the feasibility of this method is verified by NACA hydrofoil and NASA flat plate ***,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is *** research results show that the error of the calculated cavitation pressure distribution for NACA hydrofoil between the simulation test and the experimental-test is less than 5%,and the maximum error of calculated cavitation number at pump head dropping for NASA high-speed flat plate inducer between the simulation test and the experimental-test is 2.1%.The cavitation area observed in the simulation test is the same as that obtained in the high-speed photography *** on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately *** error of the calculated cavitation number at pump head dropping between the simulation test and the experimental test is about 3.7%,showing high calculation accuracy.

关键词： Aero engine Fuel centrifugal pump Multiphase flow OpenFOAM Volume of fluid

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双立柱巷道式堆垛机的平稳性分析与结构优化

设备监理 2024年第4期 48-52,56页

作者：季富华管家辉杨振华陆杰钱吴凡弘元绿色能源股份有限公司无锡214128 南京工程学院机械工程学院南京211112

双立柱堆垛机工作过程中存在摇摆幅度大、平稳性较差的问题,严重时容易发生货物的掉落,甚至发生安全事故。针对上述问题,本文应用静力学分析与有限元模拟相结合的方法,对双立柱巷道式堆垛机的门架机构进行变形分析,结果显示在堆垛机立... 详细信息

双立柱堆垛机工作过程中存在摇摆幅度大、平稳性较差的问题,严重时容易发生货物的掉落,甚至发生安全事故。针对上述问题,本文应用静力学分析与有限元模拟相结合的方法,对双立柱巷道式堆垛机的门架机构进行变形分析,结果显示在堆垛机立柱上端和上横梁连结处是最薄弱的地方。进一步对薄弱部位和关键零部件进行优化设计,与优化前进行对比,结果表明,堆垛机结构变形量减少5.40%,最大等效应力值降低8.28%,优化数据可为堆垛机可靠性的提高提供借鉴。

关键词：堆垛机结构优化有限元分析平稳性计算

The Analysis of Existing Problems and Countermeasures about China＇s Oversea Purchase

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International Journal of Technology Management 2015年第1期 7-10页

作者： zhenhua yang Jiangxi Science and Technology Normal University Jiangxi Nanchang 197907 China

Oversea purchase has got rapid development as a new industry in our country. But its problems are increasingly prominent. This thesis aims at finding the problems and roots which hinder its development by analyzing the development situation of current oversea purchase. In addition, this thesis will look for countermeasures which are beneficial to its healthy development and promote the free development of foreign trade in our country.

关键词： Oversea Purchase Cross-border Payment Consumption Rights Protection.

A Video Captioning Method by Semantic Topic-Guided Generation

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Computers, Materials & Continua 2024年第1期78卷 1071-1093页

作者： Ou Ye Xinli Wei zhenhua Yu Yan Fu Ying yang College of Computer Science and Technology Xi’an University of Science and TechnologyXi’an710054China

In the video captioning methods based on an encoder-decoder,limited visual features are extracted by an encoder,and a natural sentence of the video content is generated using a ***,this kind ofmethod is dependent on a single video input source and few visual labels,and there is a problem with semantic alignment between video contents and generated natural sentences,which are not suitable for accurately comprehending and describing the video *** address this issue,this paper proposes a video captioning method by semantic topic-guided ***,a 3D convolutional neural network is utilized to extract the spatiotemporal features of videos during the ***,the semantic topics of video data are extracted using the visual labels retrieved from similar video *** the decoding,a decoder is constructed by combining a novel Enhance-TopK sampling algorithm with a Generative Pre-trained Transformer-2 deep neural network,which decreases the influence of“deviation”in the semantic mapping process between videos and texts by jointly decoding a baseline and semantic topics of video *** this process,the designed Enhance-TopK sampling algorithm can alleviate a long-tail problem by dynamically adjusting the probability distribution of the predicted ***,the experiments are conducted on two publicly used Microsoft Research Video Description andMicrosoft Research-Video to Text *** experimental results demonstrate that the proposed method outperforms several state-of-art ***,the performance indicators Bilingual Evaluation Understudy,Metric for Evaluation of Translation with Explicit Ordering,Recall Oriented Understudy for Gisting Evaluation-longest common subsequence,and Consensus-based Image Description Evaluation of the proposed method are improved by 1.2%,0.1%,0.3%,and 2.4% on the Microsoft Research Video Description dataset,and 0.1%,1.0%,0.1%,and 2.8% on the Microsoft Research-Video to Text dataset

关键词： Video captioning encoder-decoder semantic topic jointly decoding Enhance-TopK sampling

The International Competitiveness Analysis of the Current China＇s Solar Photovoltaic Industry

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International Journal of Technology Management 2015年第5期 11-15页

作者： yang zhenhua Jiangxi Science and Technology Normal University Jiangxi Nanchang197907

Solar energy is one of clean energies which has the most development and application prospect. And solar photovoltaic industry is the main force foe the development of new energy industry. This paper points out the obstacles which improves the international competitiveness of China＇ s photovoltaic industry based on the analysis of the three big indexes, namely the international competitiveness of photovoltaic industry IMS, TCD and RCI, and proposes the suggestion which enhances the competitive advantage of China＇ s solar photovoltaic industry.

关键词： Solar Photovoltaic Industry International Competitiveness Solar Photovoltaic Industry Chain