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Bridging the Gap between Non-Symbolic and Symbolic Processing:How Could Human Being Acquire Language﹖
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作者 Setsuo Ohsuga 《南昌工程学院学报》 CAS 2006年第2期15-15,共1页
Information plays various roles for supporting human activity.Its basic role is to describe objects in the world.Form of representation is first decided,then method of its processing can be defined on its basis.Thus a... Information plays various roles for supporting human activity.Its basic role is to describe objects in the world.Form of representation is first decided,then method of its processing can be defined on its basis.Thus an information processing paradigm is defined.As human activity gets more and more complicated,information also becomes more and more sophisticated.Form of representation and processing method become the more complicated. 展开更多
关键词 very Bridging the Gap between non-symbolic and Symbolic processing
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Influence of Blade Number on the Performance of Hydraulic Turbines in the Transition Stage
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作者 Fengxia Shi Guangbiao Zhao +1 位作者 Yucai Tang Dedong Maand Xiangyun Shi 《Fluid Dynamics & Materials Processing》 EI 2024年第11期2617-2636,共20页
To analyze the effect of blade number on the performance of hydraulic turbines during the transient stage in which theflow rate is not constant,six hydraulic turbines with different blade numbers are considered.The ins... To analyze the effect of blade number on the performance of hydraulic turbines during the transient stage in which theflow rate is not constant,six hydraulic turbines with different blade numbers are considered.The instantaneous hydraulic performance of the turbine and the pressure pulsation acting on the impeller are investigated numerically by using the ANSYS CFX software.The ensuing results are compared with the outcomes of experimental tests.It is shown that thefluctuation range of the pressure coefficient increases with time,but the corresponding range for the transient hydraulic efficiency decreases gradually when theflow velocity transits to larger values.During the transition to smallflow velocity,thefluctuation range of the pressure coefficient gradually decreases as time passes,but the correspondingfluctuation range of its transient hydraulic efficiency gradually becomes larger.Thefluctuation range in the Z9 case is small during the transition.The main frequency of transient hydraulic efficiency pulsation is equal to the blade frequency.At the main frequency,Z7 has the largest amplitude of the hydraulic efficiency pulsation,Z10 has the smallest amplitude,and the difference between Z7 and Z9 is limited.As the number of blades grows,the pressure pulsation during the transition process gradually decreases,but the pressure pulsation of Z10 at the volute tongue is larger.In the steady state,Z9 has the highest efficiency and in the transient stage,the pressure coefficientfluctuation range is small.Accordingly,for the hydraulic turbine Z9,the performance is optimal. 展开更多
关键词 Hydraulic turbine blade number transient process pressurefluctuation transient hydraulic performance
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Numerical Study of the Efficiency of Multi-Layer Membrane Filtration in Desalination Processes
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作者 Salma Moushi Jaouad Ait lahcen +5 位作者 Ahmed El Hana Yassine Ezaier Ahmed Hader Imane Bakassi Iliass Tarras Yahia Boughaleb 《Fluid Dynamics & Materials Processing》 EI 2024年第11期2509-2521,共13页
Multi-layer membrane filtration is a widely used technology for separating and purifying different components ofa liquid mixture. This technique involves passing the liquid mixture through a series of membranes with de... Multi-layer membrane filtration is a widely used technology for separating and purifying different components ofa liquid mixture. This technique involves passing the liquid mixture through a series of membranes with decreasing pore sizes, which allows for the separation of different components according to their molecular size. Thisstudy investigates the filtration process of a fluid through a two-dimensional porous medium designed forseawater desalination. The focus is on understanding the impact of various parameters such as the coefficientof friction, velocity, and the number of layers on filtration efficiency. The results reveal that the number of layersplays a crucial role in desalination, with an increase in layers leading to enhanced filtration quality, following apower law relationship. The study explores the influence of the coefficient of friction on filtration performance,emphasizing its significant effect on the number of particles filtered over time. Additionally, the role of the initialvelocity in filtration efficiency is examined, showing distinct effects at both high and low velocities. Biofouling isidentified as a factor influencing filtration, with an initial increase in filtered particles followed by a decline due toparticle accumulation in pores. 展开更多
关键词 Desalination process membranefiltration Langevin dynamic fluid velocity number of layers filtered particles
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Number of Tardy Jobs of Single Machine Scheduling Problem with Variable Processing Time
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作者 朱健梅 《Journal of Modern Transportation》 1999年第1期88-95,共8页
The number of tardy jobs of the single machine scheduling problem with a variable processing time is studied in accordance with the published instances of traffic transportation management engineering. It is proved ... The number of tardy jobs of the single machine scheduling problem with a variable processing time is studied in accordance with the published instances of traffic transportation management engineering. It is proved by 3 partition problem that if the problem is of ready time and common deadline constrained, its complexity is NP hard in the strong sense. Finally, a polynomial algorithm for solving unit processing time and common deadline problems is proposed. 展开更多
关键词 number of tardy JOBS single machine scheduling problem VARIABLE processing time STRONG NP HARDNESS algorithm.
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Rapid Determination of Seed Number and Thousand Kernel Weight of Asparagus officinalis L.Using Image Processing Method
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作者 Huimin GAO Yu TIAN +1 位作者 Zhiqiang LIU Yanpo CAO 《Asian Agricultural Research》 2019年第11期53-55,共3页
Asparagus officinalis L.is favored by its high health function,but its hybrid seeds are expensive.The amount of seed,seed plumpness and germination rate are related to the production costs of breeding enterprises and ... Asparagus officinalis L.is favored by its high health function,but its hybrid seeds are expensive.The amount of seed,seed plumpness and germination rate are related to the production costs of breeding enterprises and large growers.Therefore,it is necessary to investigate the seed number and thousand kernel weight of A.officinalis L.This study developed a quick and accurate method to measure the seed number and thousand kernel weight of A.officinalis L.using image processing technology.Seed sample of A.officinalis L.was scanned with 200 dpi resolution,and the seed number was then obtained using Image-ProPlus software.After weighing the seeds,thousand kernel weight was finally calculated.By recording‘macro’,the batch processing of the samples can also be realized.This method is simple and accurate,and can greatly save the time of investigation. 展开更多
关键词 ASPARAGUS OFFICINALIS L. SEED number Thousand KERNEL WEIGHT Image processing method
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ON THE BASIC REPRODUCTION NUMBER OF GENERAL BRANCHING PROCESSES 被引量:1
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作者 蓝国烈 马志明 孙苏勇 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期1081-1094,共14页
Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual ... Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual CMJ processes. We discuss also some properties of the extinction probability and the generating operator of general branching processes. As an application in epidemics, in the final section we suggest a generalization of SIR model which can describe infectious diseases transmission in an inhomogeneous population. 展开更多
关键词 general branching process extinction probability reproduction kernel spectral radius TNC condition basic reproduction number SIR model
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Characterization of aluminum based functionally graded composites developed via friction stir processing 被引量:2
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作者 Venkatesh BIKKINA Sadasiva Rao TALASILA Kumar ADEPU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第7期1743-1755,共13页
Al/SiC functionally graded material(FGM) was developed through a novel multi-step friction stir processing(FSP) method. Si C particles with a mean size of 27.5 μm were embedded in the groove on the 6082-Al plate. To ... Al/SiC functionally graded material(FGM) was developed through a novel multi-step friction stir processing(FSP) method. Si C particles with a mean size of 27.5 μm were embedded in the groove on the 6082-Al plate. To create a graded structure over a predefined value, FSP was carried out with three tools with different pin lengths and with varying volume fractions of SiC particles. The structure was formed by passing tools with 1-3 passes with a constant rotational and traveling speeds of 900 r/min and 20 mm/min, respectively. The experiments were conducted at room temperature. Microstructural features of functionally graded(FG) samples were examined by using scanning electron microscopy(SEM) and 3D light microscopy. Mechanical properties in terms of wear resistance and microhardness were thoroughly assessed. The results indicate that the increase in FSP pass number causes more uniform SiC particle dispersion. The microhardness values were impacted by the number of passes and improved by 51.54% for Pass 3 when compared to as-received 6082-Al. Wear resistance of Al/SiC FG samples was found to increase as a result of the addition of SiC particles. 展开更多
关键词 functionally graded composites friction stir processing silicon carbide AA6082-T6 number of passes
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Effect of Processing Conditions on the Interlaced Yarn
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作者 李龙 Shuichi TANOUE Yoshiyuki IEMOTO 《Journal of Donghua University(English Edition)》 EI CAS 2008年第1期37-40,共4页
A new interlacer is used in this paper to investigate the effect of processing conditions on the properties of interlaced yarn. The experimental results show that number of tangles of interlaced yarn changes little wi... A new interlacer is used in this paper to investigate the effect of processing conditions on the properties of interlaced yarn. The experimental results show that number of tangles of interlaced yarn changes little with air pressure from 0.2 MPa to 0.5 MPa, and the number of tangles has a maximum value with yarn speed changing. For two yarn directions of entering and leaving yarn guide of interalcer, the yarn speed for the maximum number of tangles is 400 m/rain and 600 m/rain, respectively. The number of tangles changes with air pressure and yarn speed for two yarn directions is compared. 展开更多
关键词 Interlaced yarn number of tangles processing condition
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Dividing Process in Base-10 Number System Reversed Dividing Process for 1/X
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作者 Nick Huang 《Journal of Mathematics and System Science》 2015年第7期307-308,共2页
A new set of steps for dividing process, the Reversed Dividing Process, is introduced, in which the position based number representation digits for the value of l/X are reversely output one by one compared with digit ... A new set of steps for dividing process, the Reversed Dividing Process, is introduced, in which the position based number representation digits for the value of l/X are reversely output one by one compared with digit output order of the normal dividing process. 展开更多
关键词 Dividing process Natural number INTEGER PRIMES Composite numbers and Repeating Fractions.
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基于纹理特征与深度学习的小麦图像中的穗粒分割与计数
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作者 许鑫 耿庆 +2 位作者 郑凯 石磊 马新明 《江苏农业学报》 CSCD 北大核心 2024年第4期661-674,共14页
穗粒数是小麦产量构成的重要因素和估测产量的参数之一,传统的人工计数方法耗时费力,人为因素影响大。为了实现对小麦穗粒数的智能、快速监测,以百农307、新麦26、稷麦336这3个小麦品种为试验材料,利用智能手机于小麦灌浆后期拍摄麦穗图... 穗粒数是小麦产量构成的重要因素和估测产量的参数之一,传统的人工计数方法耗时费力,人为因素影响大。为了实现对小麦穗粒数的智能、快速监测,以百农307、新麦26、稷麦336这3个小麦品种为试验材料,利用智能手机于小麦灌浆后期拍摄麦穗图像,随后对麦穗图像进行预处理并归一化为480×480像素大小,结合深度学习和迁移学习机制,构建基于冻结-解冻机制的HRNet模型的小麦小穗图像分割计数深度学习模型,利用图像处理算法、小麦小穗图像纹理特征确定小穗像素数与穗粒数之间的关系阈值,构建小穗粒数预测模型,实现对小麦穗粒的预测计数。结果表明,对比同样采用冻结-解冻机制的PSPNet模型、DeeplabV3+分割模型、U-Net模型及无冻结解冻机制的HRNet模型,采用基于冻结-解冻机制的HRNet模型对小麦小穗的分割效果更优,且具有更好的鲁棒性,分割精确度为0.9594,平均交并比(mIoU)为0.9119,类别平均像素准确率(mPA)为0.9419,召回率为0.9419;通过3个不同品种小麦的麦穗图像对小穗进行计数,所得决定系数(R2)为0.92,平均绝对误差为0.73,平均相对误差为2.89%;籽粒计数的R2为0.92,平均绝对误差为0.43,平均相对误差为5.51%。由研究结果可知,基于冻结-解冻机制得出的HRNet模型的小麦小穗图像分割算法能够有效分割小麦图像中的小穗,并获得更加丰富的语义信息,可用于解决小目标图像分割困难及训练欠拟合问题,通过粒数预测模型可以快速、精确地对小麦的籽粒数进行预测,从而为小麦高效、智能化估产提供算法支撑。 展开更多
关键词 麦穗 籽粒数 图像处理 HRNet 深度学习 图像分割
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基于组合赋权云模型的塔台管制系统运行安全评估 被引量:1
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作者 张兆宁 石峰 《安全与环境学报》 CAS CSCD 北大核心 2024年第4期1254-1265,共12页
随着我国民航业的迅猛发展,空中交通流量不断攀升,机场塔台管制系统的运行安全面临严峻考验,因此,正确识别和评估风险成为有效提高塔台管制系统运行安全水平的重要前提。为精准且有效地完成对塔台管制系统运行的安全评估,构建了基于模... 随着我国民航业的迅猛发展,空中交通流量不断攀升,机场塔台管制系统的运行安全面临严峻考验,因此,正确识别和评估风险成为有效提高塔台管制系统运行安全水平的重要前提。为精准且有效地完成对塔台管制系统运行的安全评估,构建了基于模糊决策实验室分析法(Decision-Making Trial and Evaluation Laboratory,DEMATEL)网络层次分析法(Analytic Network Process,ANP)熵权法云模型的塔台管制系统运行安全评估模型。首先,通过流程图法并结合人机环管的思想建立塔台管制系统运行安全评估指标体系,并采用模糊DEMATEL法确定评估指标间的相互影响关系,绘制评估指标之间的网络结构图;然后,通过ANP法确定各评估指标的主观权重,采用熵权法确定各评估指标的客观权重,并通过博弈论方法计算评估指标的综合权重;最后,将权重结果与评语层云模型结合使用对各级安全评估指标进行安全评估,通过MATLAB软件完成算例的仿真分析。结果表明:该塔台管制系统运行安全等级在一般和良好之间,仍需采取有效措施对某些风险因素进行控制;同时验证了该模型在塔台管制系统运行安全评估中具有可行性和准确性,对塔台管制系统安全评估具有指导意义。 展开更多
关键词 安全工程 三角模糊数 决策实验室分析法(DEMATEL) 网络层次分析法(ANP) 熵权法 云模型 塔台管制
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基于TFN-AHP和云模型的母舰对气垫船保障能力评价
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作者 狄鹏 陈鹏宇 +2 位作者 刘昊邦 张帆 黄钧 《海军工程大学学报》 CAS 北大核心 2024年第2期55-60,共6页
母舰对气垫船的保障能力是气垫船任务执行能力的重要组成部分,对母舰的保障能力进行综合评价是提升气垫船与母舰保障适配能力的重要环节。母舰对气垫船的保障活动具有高度的随机性、复杂性和动态性,导致其保障能力的评价也存在不确定性... 母舰对气垫船的保障能力是气垫船任务执行能力的重要组成部分,对母舰的保障能力进行综合评价是提升气垫船与母舰保障适配能力的重要环节。母舰对气垫船的保障活动具有高度的随机性、复杂性和动态性,导致其保障能力的评价也存在不确定性和模糊性。为此,基于三角模糊数(triangular fuzzy number,TFN)-层次分析法(analytic hierarchy process,AHP)与云模型提出了一种新的母舰对气垫船保障能力评价方法,并对某型母舰对气垫船的保障能力进行了评价。该方法通过特定的结构算法完成定性概念与定量表示的相互结合,降低了保障能力评价中权重计算的主观性和随机性,为母舰对气垫船保障能力评价提供了借鉴。 展开更多
关键词 气垫船 母舰 三角模糊数 层次分析法 云模型 保障能力评价
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基于TFN-AHP熵权的铁钻工工业设计方案评价
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作者 王维旭 夏博昌 +2 位作者 刘旬 吕志鹏 李享 《石油机械》 北大核心 2024年第7期70-77,共8页
针对铁钻工工业设计方案评价综合性强、存在一定主观性、评价影响因素多的问题,提出一种基于三角模糊数层次分析法和熵权法主、客观方法相结合的铁钻工方案评价模型。该模型在层次分析法框架下,根据专家意见构建铁钻工工业设计方案评价... 针对铁钻工工业设计方案评价综合性强、存在一定主观性、评价影响因素多的问题,提出一种基于三角模糊数层次分析法和熵权法主、客观方法相结合的铁钻工方案评价模型。该模型在层次分析法框架下,根据专家意见构建铁钻工工业设计方案评价指标体系,划分4项1级指标和12项2级指标,以模糊决策矩阵为评价信息载体,引入三角模糊数优化传统层次分析法不能准确表征带有模糊不确定性特征的评价信息的问题,并使用客观方法熵权法组合赋权确定综合权重。将此评价模型运用于实际铁钻工设计项目方案评价,将评价结果与相关传统评价法进行对比,并将筛选出来的方案进行深入优化设计,证明了评价模型的有效性。研究结果能够有效辅助企业进行铁钻工工业设计方案决策。 展开更多
关键词 铁钻工 层次分析法 熵权法 三角模糊数 综合评价方法
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基于实数化的均匀圆阵矩阵重构方法
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作者 张涛 刘鲁涛 《应用科技》 CAS 2024年第4期122-128,共7页
为了减小低快拍数和低信噪比下采样协方差矩阵误差,并降低其运算复杂度,提出了一种基于实数化的均匀圆阵采样协方差矩阵重构方法。针对均匀圆阵的特点,通过组建特殊的基向量,构成特殊的重构矩阵。通过将采样协方差矩阵实数化,进一步降... 为了减小低快拍数和低信噪比下采样协方差矩阵误差,并降低其运算复杂度,提出了一种基于实数化的均匀圆阵采样协方差矩阵重构方法。针对均匀圆阵的特点,通过组建特殊的基向量,构成特殊的重构矩阵。通过将采样协方差矩阵实数化,进一步降低了重构矩阵的复杂度。考虑到多通道不一致性对重构矩阵的影响,引入0位校正算法,提高了重构方法的稳健性。最后应用重构后的协方差矩阵进行子空间类波达方向估计(direction of arrival,DOA)。实验仿真证明,该特殊重构矩阵在实数化下与原矩阵重构能力相同;当快拍数为100、信噪比为0 dB时,双信源分辨力较重构前由74%提高到95%以上;理论重构运算复杂度降低到原来的53.99%。 展开更多
关键词 矩阵重构 实数化 波达方向估计 子空间恢复 0位校正 阵列信号处理 高分辨 基向量
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基于TFAHP的电炉企业多维一体化财务模式评价模型
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作者 梁晨 《工业加热》 CAS 2024年第1期71-74,共4页
电炉企业的财务由于其参数指标众多,对相关模式评价过程不能运用单一阈值理论,评价过程一直是个难题。设计基于TFAHP的电炉企业多维一体化财务模式评价模型。通过微观模拟电炉企业财务工资过程,确定评价指标,由此构建模糊评价矩阵,依据... 电炉企业的财务由于其参数指标众多,对相关模式评价过程不能运用单一阈值理论,评价过程一直是个难题。设计基于TFAHP的电炉企业多维一体化财务模式评价模型。通过微观模拟电炉企业财务工资过程,确定评价指标,由此构建模糊评价矩阵,依据模糊评价矩阵,构建二级评价矩阵,在单一准则下计算各评价指标的相对权重,采用三角模糊数层次分析法确定总权重,由此构建评价模型,获取评价结果,设定评价等级集合及区间值,给出具体评语等级。实验可知,所构建模型进行多维一体化财务模式评价在电炉企业应用效果较好,评价效率较高。 展开更多
关键词 三角模糊数层次分析法 多维一体化 财务模式 评价矩阵 指标权重
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基于直觉模糊环境的海上风机选型
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作者 邵萌 毛智谋 +2 位作者 孙金伟 管笑 伊传秀 《科学技术与工程》 北大核心 2024年第16期6649-6658,共10页
选择合适的海上风力发电机机型对海上风电场的长期高效运行起着至关重要的作用。针对决策者在风机选型决策过程中存在不确定性和主观偏好等问题,提出一种改进的多准则决策(multi-criteria decision making, MCDM)框架及方法:在权重求解... 选择合适的海上风力发电机机型对海上风电场的长期高效运行起着至关重要的作用。针对决策者在风机选型决策过程中存在不确定性和主观偏好等问题,提出一种改进的多准则决策(multi-criteria decision making, MCDM)框架及方法:在权重求解算法中将群体决策和直觉模糊数与层次分析法相结合,提出群体直觉模糊层次分析法(group intuitionistic fuzzy analytic hierarchy process, GIAHP)计算指标权重;在备选方案排序算法中将余弦距离引入接近理想点法(technique for order preference by similarity to an ideal solution, TOPSIS),提出多距离TOPSIS确定备选方案排序。最后以山东省海上风电场风机选型为例,并通过敏感性分析验证框架及方法的鲁棒性。该框架及方法为中国海上风电场风机选型提供理论依据,可确保海上风电场长期稳定运行。 展开更多
关键词 海上风机选型 直觉模糊数 群体直觉模糊层次分析法(GIAHP) 多距离接近理想点法(TOPSIS)
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超声生物显微镜在超声睫状体成形术中的应用 被引量:1
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作者 杜梅 律鹏 +1 位作者 刘佳卉 王雅东 《兰州大学学报(医学版)》 2024年第4期48-52,共5页
目的 探讨超声生物显微镜在超声睫状体成形术中的应用。方法 采用回顾性病例分析方法,纳入2020年8月—2021年7月在兰州大学第二医院眼科进行超声睫状体成形术的23例青光眼患者,对比术眼术前、术后1周、术后1个月、术后3个月的超声生物... 目的 探讨超声生物显微镜在超声睫状体成形术中的应用。方法 采用回顾性病例分析方法,纳入2020年8月—2021年7月在兰州大学第二医院眼科进行超声睫状体成形术的23例青光眼患者,对比术眼术前、术后1周、术后1个月、术后3个月的超声生物显微镜检查结果,记录分析不同时间段睫状体与睫状突形态学上的差异。结果 23例患者术前平均眼压为(44.83±6.25) mmHg,术后1周平均眼压降低了38.9%,术后1个月平均眼压降低了43.2%,术后3个月平均眼压降低了43.8%,差异均有统计学意义(P <0.001)。超声生物显微镜检查发现青光眼患者在超声睫状体成形术术前和术后不同时间中睫状突厚度,睫状突数量均有变化,与术前相比,术后不同时间段睫状突厚度减小,睫状突数量减少,差异均具有统计学意义(P <0.05)。结论 超声生物显微镜可准确观察睫状体的形态学变化,并可以定量分析,对超声睫状体成形术术前与术后睫状体形态学的观察效果明显,临床上可以用于指导超声睫状体成形术治疗参数的设定,并预判术后的治疗疗效。 展开更多
关键词 超声生物显微镜 超声睫状体成形术 睫状体 睫状突厚度 睫状突数量 形态学改变
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工艺参数对浸没式直流介电泳辅助化学机械抛光蓝宝石晶片的影响
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作者 黄展亮 柏显亭 +1 位作者 潘继生 阎秋生 《表面技术》 EI CAS CSCD 北大核心 2024年第18期144-155,共12页
目的为了实现蓝宝石晶片的高效超光滑表面加工,提出浸没式直流介电泳辅助化学机械抛光方法,研究该方法对蓝宝石晶片的加工适应性。方法搭建了浸没式直流介电泳辅助化学机械抛光系统,通过单因素实验探究接入电压、工件及抛光盘转速、偏... 目的为了实现蓝宝石晶片的高效超光滑表面加工,提出浸没式直流介电泳辅助化学机械抛光方法,研究该方法对蓝宝石晶片的加工适应性。方法搭建了浸没式直流介电泳辅助化学机械抛光系统,通过单因素实验探究接入电压、工件及抛光盘转速、偏摆移动速度、抛光时间及抛光垫类型对蓝宝石晶片的加工效果,并深入分析负介电泳效应对CMP加工过程的影响。结果直流介电泳辅助CMP方法可以显著提高蓝宝石晶片的抛光效果,在2000V的接入电压下,化学机械抛光的材料去除率MRR提高了99.97%,达到了7.53nm/min,表面粗糙度Ra降低至2.51nm,工件表面划痕数量明显减少。工件及抛光盘转速、偏摆移动速度的提升都会使抛光MRR和Ra先升后降,带槽的抛光垫对介电泳效应控制磨料起促进作用。各个因素的影响对提高有效磨料数起交互作用,负介电泳效应促使磨料聚集在抛光垫表面,而工件与抛光垫的相对运动促使磨料更新循环。结论采用接入电压2000 V、工件及抛光盘转速80 r/min、偏摆速度60 r/min,在精抛垫下抛光蓝宝石晶片90 min,可以获得表面粗糙度Ra为0.953 nm的光滑表面。 展开更多
关键词 介电泳效应 化学机械抛光 蓝宝石晶片 工艺参数 抛光垫 有效磨料数 加工效果
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基于改进动态因果图的湿法冶金浸出过程故障诊断方法研究
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作者 薛海莉 李晓敏 《湿法冶金》 CAS 北大核心 2024年第2期201-205,共5页
针对现有湿法冶金工艺机制复杂和浸出工艺故障诊断方法存在精度较差等问题,研究了用改进的动态因果图诊断湿法冶金浸出工艺故障,主要通过二元区间数对动态因果图进行优化改进,并对条件概率上下限进行加权,实现湿法冶金浸出工艺故障诊断... 针对现有湿法冶金工艺机制复杂和浸出工艺故障诊断方法存在精度较差等问题,研究了用改进的动态因果图诊断湿法冶金浸出工艺故障,主要通过二元区间数对动态因果图进行优化改进,并对条件概率上下限进行加权,实现湿法冶金浸出工艺故障诊断。结果表明:该故障诊断方法相较于常规方法,故障诊断准确率更高,能对浸出工艺的故障进行较准确的诊断。 展开更多
关键词 湿法冶金 浸出 故障诊断 动态因果图 二元区间数
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基于改进白鲸优化算法的低碳柔性工艺规划 被引量:2
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作者 孔云 周学良 冷杰武 《现代制造工程》 CSCD 北大核心 2024年第1期80-88,共9页
针对数控加工过程的低碳柔性工艺规划问题,建立了以加工过程中机床、刀具和装夹的转换次数和碳排放为目标的优化模型,提出了基于改进白鲸优化算法的求解方法。该算法通过引入变异操作增强其全局搜索能力,并在种群初始化中采用以加工资... 针对数控加工过程的低碳柔性工艺规划问题,建立了以加工过程中机床、刀具和装夹的转换次数和碳排放为目标的优化模型,提出了基于改进白鲸优化算法的求解方法。该算法通过引入变异操作增强其全局搜索能力,并在种群初始化中采用以加工资源为导向的启发式规则选择策略与随机生成相结合的方式,以提高初始种群的质量,加快算法的收敛速度。最后,以一个零件的加工信息为测试实例,验证所提模型的可行性,并与其他3种算法进行对比。试验结果表明,所提出的算法能够获得更优解,且具有更快的收敛速度。 展开更多
关键词 柔性工艺规划 碳排放 转换次数 白鲸优化算法
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