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超Grassmannian流形上的超Plücker映射
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作者 陈祎家 唐孝敏 《黑龙江大学自然科学学报》 CAS 2024年第1期15-27,共13页
■表示■-维向量空间中的■-维子空间构成的超Grassmannian流形。本文研究超Grassmannian流形上的超Plücker映射,刻画了■和■上的超Plücker映射的齐次坐标矩阵。
关键词 超丛代数 超Grassmannian流形 plücker坐标 plücker映射
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ASME规范中PL+Pb许用极限取值的探讨
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作者 吴晓敏 巩乐 +2 位作者 张万尧 徐澍 董富荣 《中国设备工程》 2024年第14期115-118,共4页
在ASME BPVC.Ⅷ.2规范中,局部一次薄膜当量应力加一次弯曲当量应力之和的限制准则为:P_(L)+P_(b)<S_(PL),是防止压力容器整体塑性垮塌的限制准则之一,是压力容器的强度设计的重中之重。在学习ASME BPVC规范及阐述其内容的相关专著时... 在ASME BPVC.Ⅷ.2规范中,局部一次薄膜当量应力加一次弯曲当量应力之和的限制准则为:P_(L)+P_(b)<S_(PL),是防止压力容器整体塑性垮塌的限制准则之一,是压力容器的强度设计的重中之重。在学习ASME BPVC规范及阐述其内容的相关专著时,会发现国内压力容器行业内的部分专家对S_(PL)如何取值存在着截然不同甚至相反的观点,导致设计人员在理解或应用ASME规范时发生困惑。本文试对关于S_(PL)取值存在的矛盾之处进行分析讨论,为压力容器设计人员提供参考。 展开更多
关键词 分析设计法 aSME BPVC 局部一次薄膜当量应力 一次弯曲当量应力 S_(pl)
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Supply Chain Management Analysis and Design for a Variety of Economic Scenarios, Including Data and System Administration
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作者 Rakibul Islam Md Eahia Ansari +2 位作者 Md Abutaher Dewan Sharmin Sultana Mir Araf Hossain Rivin 《Journal of Software Engineering and Applications》 2024年第10期770-785,共16页
Due to the rapid progress of information technology, organizations anticipate significant changes in the planning, scheduling, and optimization aspects of operation and supply chain management (SCM) shortly. Two prima... Due to the rapid progress of information technology, organizations anticipate significant changes in the planning, scheduling, and optimization aspects of operation and supply chain management (SCM) shortly. Two primary types of risk have an impact on supply chain management and design. The first group deals with the difficulties in matching supply and demand, whereas the second group deals with disruptions to regular business operations. The essay offers a theoretical framework that combines the cooperative efforts of risk assessment and mitigation, which are critical for effectively handling potential supply chain interruptions. This content provides insightful viewpoints on the strategic resources and operational structure needed to improve organizational success. We utilized the partial least squares (PLS) method to address the problem of multicollinearity and measurement mistakes in examining cause-and-effect constructs. The statistical method, Least Squares (PLS), used in structural equation modeling, is based on partial variance. The Partial Least Squares (PLS) strategy uses a two-stage estimate procedure to calculate weights, loadings, and route estimations. Initially, several simple and complex regressions were performed with the provided model. The procedure was repeated until a solution was found, resulting in a set of weights used to determine the latent variable scores. In the second step, non-iterative PLS regression yields loadings, path coefficients, mean scores, and location parameters. According to the structural study, implementing Sustainable Supply Chain Management (SSCM) can significantly improve a business’s operational and financial performance. The findings offer a comprehensive understanding of several elements of supply chain management (SSCM), including information systems, organizational configurations, supply chain network architecture (SCND), and supply chain strategy (SCS). The supply chain is essential for effectively moving goods over great distances and encouraging cooperation between parties. Therefore, these connections are established precisely, quickly, and cheaply via a knowledgeable and efficient supply chain. Two key components are necessary for a supply chain (SC) to be successful: efficient collaboration and the smooth integration of information-sharing platforms. 展开更多
关键词 SCM SCS plS Supply Chain Theory of Constraints (TOC) SaM
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An Application of Machine Learning to Thalassemia Diagnosis
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作者 Sitan Liu 《Journal of Computer and Communications》 2024年第2期211-230,共20页
Mediterranean anemia is a genetic disease that currently relies heavily on expert clinical experience to determine whether patients are affected. This method is overly reliant on expert experience and is not precise e... Mediterranean anemia is a genetic disease that currently relies heavily on expert clinical experience to determine whether patients are affected. This method is overly reliant on expert experience and is not precise enough. This paper proposes two modeling methods to predict whether patients have Mediterranean anemia. The first method involves using Principal Component Analysis (PCA) to reduce the dimensionality of the data, followed by logistic regression modeling (PCA-LR) on the reduced dataset. The second method involves building a Partial Least Squares Regression (PLS) model. Experimental results show that the prediction accuracy of the PCA-LR model is 87.5% (degree = 2, λ=4), and the prediction accuracy of the PLS model is 92.5% (ncomp = 4), indicating good predictive performance of the models. 展开更多
关键词 MULTICOLLINEaRITY Statistical analysis Models Data Mining PCa-LR plS
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基于SG-Lasso-PLS融合算法的水体硝酸盐氮紫外光谱检测研究
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作者 王金梅 何适 +4 位作者 张航熙 杨晨 尹义同 张莉 郑培超 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2023年第4期1037-1042,共6页
硝酸盐氮(NO3-N)是水中“三氮”(硝酸盐氮、亚硝酸盐氮、氨氮)之一,能够反映水体受污染的程度,是水质评估的一项重要指标。水体中的硝酸盐氮浓度过高不仅会导致水环境污染加重,而且会对人畜及水产构成较大威胁。传统的硝酸盐氮检测必须... 硝酸盐氮(NO3-N)是水中“三氮”(硝酸盐氮、亚硝酸盐氮、氨氮)之一,能够反映水体受污染的程度,是水质评估的一项重要指标。水体中的硝酸盐氮浓度过高不仅会导致水环境污染加重,而且会对人畜及水产构成较大威胁。传统的硝酸盐氮检测必须先反应后测定,具有时间长、操作复杂、有二次污染等缺点。光谱法具有快速、无损、无试剂消耗等显著优点。针对硝酸盐氮难以快速检测的问题,提出了一种基于紫外吸收光谱的快速定量分析硝酸盐氮的方法。采集42份浓度为0~20 mg·L^(-1)的硝酸盐氮标准溶液样本的紫外吸收光谱,每份样本经11次平均处理以减少仪器噪声和环境的影响。采用SPXY算法按照7∶3的比例划分训练集、测试集,对紫外吸收光谱数据使用Savitzky-Golay(SG)滤波算法进行预处理,通过10折叠交叉验证获得套索回归(lasso regression)合适的正则化参数λ=0.2036,再使用Lasso回归在全光谱范围内筛选出与硝酸盐氮相关的光谱特征波长,将特征波长处的吸光度与样本浓度进行偏最小二乘(PLS)拟合建立硝酸盐氮的回归模型。采用此建模方法所建立的模型训练集的R2与RMSE分别为0.99991和0.06015 mg·L^(-1),测试集的R2与RMSE分别为0.99972和0.04691 mg·L^(-1)。为了验证提出的SG-Lasso-PLS预测模型效果,另外建立了Lasso-PLS,SG-PCA-PLS和SG-PCA-SVR三种预测模型进行对比。验证结果表明,SG-Lasso-PLS建立的预测模型的R2和RMSE均优于其他三种预测模型。说明SG滤波能够消除光谱信号的随机噪声,提高模型的预测精度。与PCA数据降维算法相比,Lasso可实现全光谱范围内的光谱特征选择和数据降维,能有效消除光谱数据的冗余信息,提高模型的预测精度。因此,本文提出的SG-Lasso-PLS混合模型能够快速准确的对水体中的硝酸盐氮进行预测。作为硝酸盐氮浓度检测的基础研究,能为快速无污染的水质在线监测场景提供算法参考。 展开更多
关键词 硝酸盐氮 紫外吸收光谱 Lasso回归 plS回归
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4PL供应链融资体系多方安全隐私计算的信息共享机制研究
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作者 赵成国 张岩杰 王军 《经济师》 2024年第5期7-10,共4页
目前4PL供应链融资业务随着技术的提升,在获取大数据信息的同时,也产生了“信息壁垒”“数据泄露”“数据权限”等信息安全共享问题。在4PL供应链融资业务中,在隐私安全的基础上提升数据资源共享。文章首先分析目前4PL供应链融资结构和... 目前4PL供应链融资业务随着技术的提升,在获取大数据信息的同时,也产生了“信息壁垒”“数据泄露”“数据权限”等信息安全共享问题。在4PL供应链融资业务中,在隐私安全的基础上提升数据资源共享。文章首先分析目前4PL供应链融资结构和要素关系及相关信息流通问题,然后从数据安全共享的层面出发,结合隐私计算的多方安全计算技术,构建了一种安全的4PL信息平台并分析其共享机制用以增加参与主体间的信任度,从而提高4PL供应链融资的效率,并且建立数据管控系统和动态协作管理架构以增强4PL企业在供应链融资中的功能。 展开更多
关键词 4pl 隐私计算 数据安全 共享机制
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基于PSO-PLS煤泥浮选加药量预测模型
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作者 刘海增 李玉娇 徐昊 《化学工程与技术》 2024年第4期326-343,共18页
煤泥浮选药剂添加量的精确控制对浮选效果至关重要,是智能浮选的重要因素,也是近几年浮选智能科研工作者的研究课题。药剂量添加不当会导致浮选精煤灰分存在较大波动。影响浮选药剂添加量的因素众多,本文考虑入料浓度、入料流量、补水... 煤泥浮选药剂添加量的精确控制对浮选效果至关重要,是智能浮选的重要因素,也是近几年浮选智能科研工作者的研究课题。药剂量添加不当会导致浮选精煤灰分存在较大波动。影响浮选药剂添加量的因素众多,本文考虑入料浓度、入料流量、补水量、精煤灰分和尾煤灰分这五种因素对煤泥浮选药剂添加量的影响,提出了一种基于粒子群优化(PSO)偏最小二乘(PLS)算法的煤泥浮选起泡剂和捕收剂加药量预测模型。通过对比PCA、PLS和PSO-PLS三种算法的预测效果,发现PSO-PLS模型在预测精度和稳健性上表现优异,均方差、均方根误差、平均绝对百分比误差显著低于前两者,捕收剂预测R2值达到0.7863,起泡剂预测R2值达到0.8320,表明其拟合效果良好。实验证明,PSO-PLS算法能够准确预测浮选药剂添加量,有助于实现选煤厂浮选加药过程的智能化,为进一步选煤厂智能化建设提供了技术支持。 展开更多
关键词 浮选 起泡剂 捕收剂 PSO plS
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基于S7-200 SMART PLC的PLS指令控制步进电机 被引量:1
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作者 李春晓 王鹏 程卫东 《电工技术》 2023年第4期4-6,共3页
步进电机的工作原理是将接收到的脉冲信号转化成与之相对应的角位移或直线位移,因此步进电机能够实现控制并应用于自动化生产中。基于西门子SMART系列给出一种通过人机交互(HMI)实时修改运动控制参数,实现控制PLC高速脉冲(PLS)输出的应... 步进电机的工作原理是将接收到的脉冲信号转化成与之相对应的角位移或直线位移,因此步进电机能够实现控制并应用于自动化生产中。基于西门子SMART系列给出一种通过人机交互(HMI)实时修改运动控制参数,实现控制PLC高速脉冲(PLS)输出的应用例程序。 展开更多
关键词 步进电机 高速脉冲 SMaRT plS plC
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A Line Complex-Based Evolutionary Algorithm for Many-Objective Optimization 被引量:3
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作者 Liang Zhang Qi Kang +2 位作者 Qi Deng Luyuan Xu Qidi Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第5期1150-1167,共18页
In solving many-objective optimization problems(MaO Ps),existing nondominated sorting-based multi-objective evolutionary algorithms suffer from the fast loss of selection pressure.Most candidate solutions become nondo... In solving many-objective optimization problems(MaO Ps),existing nondominated sorting-based multi-objective evolutionary algorithms suffer from the fast loss of selection pressure.Most candidate solutions become nondominated during the evolutionary process,thus leading to the failure of producing offspring toward Pareto-optimal front with diversity.Can we find a more effective way to select nondominated solutions and resolve this issue?To answer this critical question,this work proposes to evolve solutions through line complex rather than solution points in Euclidean space.First,Plücker coordinates are used to project solution points to line complex composed of position vectors and momentum ones.Besides position vectors of the solution points,momentum vectors are used to extend the comparability of nondominated solutions and enhance selection pressure.Then,a new distance function designed for high-dimensional space is proposed to replace Euclidean distance as a more effective distancebased estimator.Based on them,a novel many-objective evolutionary algorithm(MaOEA)is proposed by integrating a line complex-based environmental selection strategy into the NSGAⅢframework.The proposed algorithm is compared with the state of the art on widely used benchmark problems with up to 15 objectives.Experimental results demonstrate its superior competitiveness in solving MaOPs. 展开更多
关键词 Environmental selection line complex many-objective optimization problems(MaOPs) plücker coordinate
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Pls3突变相关新型早发骨质疏松大鼠模型的心血管改变及机制
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作者 周冰娜 赵笛辰 +6 位作者 胡静 张茜 王鸥 夏维波 邢小平 陈太波 李梅 《中华骨质疏松和骨矿盐疾病杂志》 CSCD 北大核心 2024年第2期114-122,共9页
目的基于自主构建的丝束蛋白3(Plastin 3,PLS3)大片段基因Pls3敲除的新型骨质疏松大鼠模型,评估心血管表型及其与胶原代谢的关系。方法采用CRISPR/Cas9技术构建Pls3基因10~16外显子大片段敲除的大鼠模型(Pls3^(E10-16del/0)),与野生型... 目的基于自主构建的丝束蛋白3(Plastin 3,PLS3)大片段基因Pls3敲除的新型骨质疏松大鼠模型,评估心血管表型及其与胶原代谢的关系。方法采用CRISPR/Cas9技术构建Pls3基因10~16外显子大片段敲除的大鼠模型(Pls3^(E10-16del/0)),与野生型大鼠进行心脏表型比较,采用免疫组化染色了解PLS3蛋白在心血管的表达,采用超声心动评估大鼠心血管形态及功能,HE染色了解心脏组织学改变,使用扫描电镜评估心脏胶原蛋白的微结构及排列。结果PLS3在野生型大鼠心血管组织细胞质中广泛表达,在Pls3^(E10-16del/0)大鼠心血管的表达明显减少。6~8周龄Pls3^(E10-16del/0)大鼠的心脏及大血管结构与功能未见明显异常,但与野生型大鼠相比,其存在右心室舒张末内径及近端升主动脉内径缩小,血管内皮细胞减少及排列紊乱。Pls3^(E10-16del/0)大鼠心血管组织中的胶原合成未受影响,但电镜下可见其心脏及升主动脉中的细胶原纤维断裂、排列散乱。结论本研究首次对新型Pls3基因大片段敲除的早发骨质疏松大鼠模型心血管系统进行研究,发现其右心室及升主动脉内径缩小,出现细胶原纤维断裂、排列散乱的异常改变,其对心血管系统的结构与功能的远期影响,有待观察,研究拓展了对Pls3相关骨质疏松症心血管表型的认识。 展开更多
关键词 早发骨质疏松症 pls3基因突变 心血管表型
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冰草1PS和1PL易位染色体导入不同小麦背景改良株型的遗传效应评价
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作者 康西璐 韩舶辉 +8 位作者 王筱 韩海明 周升辉 鲁玉清 刘伟华 李秀全 杨欣明 张锦鹏 李立会 《植物遗传资源学报》 CAS CSCD 北大核心 2024年第2期193-205,共13页
冰草(Agropyron cristatum L.,2n=4x=28,PPPP)携带的多样性外源基因是小麦遗传改良重要基因源。前期研究表明冰草1P染色体上的基因可以改良小麦株叶型,但在获得易位系的基础上,外源片段导入不同背景小麦品种的叶型变化以及可能带来的不... 冰草(Agropyron cristatum L.,2n=4x=28,PPPP)携带的多样性外源基因是小麦遗传改良重要基因源。前期研究表明冰草1P染色体上的基因可以改良小麦株叶型,但在获得易位系的基础上,外源片段导入不同背景小麦品种的叶型变化以及可能带来的不利遗传连锁累赘还不清楚。为进一步探究小麦-冰草T1PS·1AL和T1AS·1PL易位系在不同小麦背景中对主要农艺性状的遗传效应,本研究将小麦-冰草1PS、1PL易位系与藁城8901、百农607、漯麦163、百农207、西农979、中麦578、川麦104、宁麦资126等8个普通小麦品种进行杂交,对F2分离群体的农艺性状进行考察和分析。结果表明,冰草1PS染色体导入小麦后,降低了小麦的倒三叶长,株高也显著降低3~8 cm,产量性状基本不受影响。冰草1PL染色体使小麦株高降低,旗叶、倒二叶和倒三叶显著缩短,改变株型的同时,小麦的产量性状同时降低,具有连锁累赘。在冰草1P易位系中,后代的表型除与染色体本身所产生的效应有关外,也与小麦受体的遗传背景相关。在不同背景的小麦亲本杂交组合后代中,可以选出株叶型改良且产量性状不受影响的单株用于小麦的遗传改良。研究表明2个小麦-冰草1P易位系创新种质在株型改良上具有显著的遗传效应,可以为冰草1P染色体易位片段的利用提供指导。 展开更多
关键词 冰草 T1PS·1aL易位系 T1aS·1pl易位系 株型 遗传效应
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PLS1基因突变致非综合征型耳聋的研究进展
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作者 熊奕康 王海伟 +1 位作者 黄海龙 徐两蒲 《中华耳科学杂志》 CSCD 北大核心 2024年第2期317-321,共5页
PLS1基因(OMMI:602734)编码PLS1蛋白。PLS1蛋白是一种肌动蛋白捆绑蛋白,在横结肠、小肠末端和内耳细胞中均有表达,参与微绒毛的组成,有助于维持静纤毛的稳定性。研究发现,PLS1基因突变将导致其表达的PLS1蛋白被破坏,从而导致不同程度的... PLS1基因(OMMI:602734)编码PLS1蛋白。PLS1蛋白是一种肌动蛋白捆绑蛋白,在横结肠、小肠末端和内耳细胞中均有表达,参与微绒毛的组成,有助于维持静纤毛的稳定性。研究发现,PLS1基因突变将导致其表达的PLS1蛋白被破坏,从而导致不同程度的轻度至重度进行性高频感音性耳聋。目前,在世界范围内已经报道了数例PLS1基因碱基替换突变突变导致常染色体显性非综合征型耳聋的病例。我们对PLS1基因突变导致非综合征型遗传性耳聋的研究进展予以综述。 展开更多
关键词 plS1 DFNa76 非综合征型耳聋 遗传性耳聋 基因突变
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Infrared Spectroscopy-Based Chemometric Analysis for Lard Differentiation in Meat Samples
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作者 Muhammad Aadil Siddiqui M.H.Md Khir +3 位作者 Zaka Ullah Muath Al Hasan Abdul Saboor Saeed Ahmed Magsi 《Computers, Materials & Continua》 SCIE EI 2023年第5期2859-2871,共13页
One of the most pressing concerns for the consumer market is the detection of adulteration in meat products due to their preciousness.The rapid and accurate identification mechanism for lard adulteration in meat produ... One of the most pressing concerns for the consumer market is the detection of adulteration in meat products due to their preciousness.The rapid and accurate identification mechanism for lard adulteration in meat products is highly necessary,for developing a mechanism trusted by consumers and that can be used to make a definitive diagnosis.Fourier Transform Infrared Spectroscopy(FTIR)is used in this work to identify lard adulteration in cow,lamb,and chicken samples.A simplified extraction method was implied to obtain the lipids from pure and adulterated meat.Adulterated samples were obtained by mixing lard with chicken,lamb,and beef with different concentrations(10%–50%v/v).Principal component analysis(PCA)and partial least square(PLS)were used to develop a calibration model at 800–3500 cm^(−1).Three-dimension PCA was successfully used by dividing the spectrum in three regions to classify lard meat adulteration in chicken,lamb,and beef samples.The corresponding FTIR peaks for the lard have been observed at 1159.6,1743.4,2853.1,and 2922.5 cm−1,which differentiate chicken,lamb,and beef samples.The wavenumbers offer the highest determination coefficient R2 value of 0.846 and lowest root mean square error of calibration(RMSEC)and root mean square error prediction(RMSEP)with an accuracy of 84.6%.Even the tiniest fat adulteration up to 10%can be reliably discovered using this methodology. 展开更多
关键词 Fourier transform infrared spectroscopy LaRD HaLaL PCa plS RMSEC RMSEP
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牛坏死杆菌白细胞毒素PL2蛋白的生物信息学分析及其原核表达鉴定
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作者 于思雯 肖佳薇 +3 位作者 毕栏 王天硕 贺显晶 郭东华 《黑龙江八一农垦大学学报》 2024年第3期38-43,98,共7页
为确定牛坏死杆菌(Fusobacterium necrophorum)白细胞毒素PL2蛋白的组成结构及生物信息学特性。根据NCBI数据库中的牛坏死杆菌白细胞毒素PL2基因序列及其编码蛋白的氨基酸序列,利用生物信息学软件对PL2蛋白的理化性质、B细胞及T细胞抗... 为确定牛坏死杆菌(Fusobacterium necrophorum)白细胞毒素PL2蛋白的组成结构及生物信息学特性。根据NCBI数据库中的牛坏死杆菌白细胞毒素PL2基因序列及其编码蛋白的氨基酸序列,利用生物信息学软件对PL2蛋白的理化性质、B细胞及T细胞抗原表位等进行了预测研究,并利用原核表达系统构建重组质粒pGEX-6p-1-PL2-1、pGEX-6p-1-PL2-2、pGEX-6p-1-PL2-3,采用SDS-PAGE检测PL2蛋白的表达,将获得的重组蛋白经Western blot验证。PL2蛋白是由332个氨基酸构成的富含丝氨酸的稳定亲水蛋白,二级结构以无规卷曲和α螺旋居多。预测该蛋白含有10个B细胞优势抗原表位和16个T细胞优势抗原表位,利用PCR扩增得到的pGEX-6p-1-PL2-1为228 bp、pGEX-6p-1-PL2-2为300 bp、pGEX-6p-1-PL2-3为588 bp。SDS-PAGE证明3个蛋白成功表达,蛋白大小为34 kDa,Western blot结果表明,该重组蛋白PL2-1具有良好的反应原性。牛坏死杆菌白细胞毒素PL2蛋白为膜外蛋白,不存在跨膜区,含有多个磷酸化位点及多个B细胞、T细胞抗原表位,根据抗原表位预测结果获得的重组蛋白PL2-1具有良好的反应原性,可作为潜在抗原用于牛坏死杆菌病亚单位疫苗研发。 展开更多
关键词 牛坏死杆菌 白细胞毒素pl2蛋白 生物信息学分析 原核表达
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AIGC赋能智慧教学设计的模型构建研究 被引量:2
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作者 邓韵 施佐晨 《设计艺术研究》 2024年第3期51-56,共6页
拟探索在AIGC背景下智慧教学设计的范式,以艺术设计类教学为视角,基于梅耶多媒体学习理论构建新的智慧教学设计模型,旨在于推动学生实现可持续发展的生成式学习。数据收集采用问卷调查法,并使用Smartpls软件进行PLS—SEM模型分析研究。... 拟探索在AIGC背景下智慧教学设计的范式,以艺术设计类教学为视角,基于梅耶多媒体学习理论构建新的智慧教学设计模型,旨在于推动学生实现可持续发展的生成式学习。数据收集采用问卷调查法,并使用Smartpls软件进行PLS—SEM模型分析研究。研究结果显示,影响智慧教学设计的两大维度分别是认知因素和情感因素,证明了情感与动机是直接影响学生可持续发展生成式学习的重要因素,并提出以下设计策略:第一,认知管理是可持续发展生成式学习的地基石;第二,情感动机是可持续发展生成式学习的助推剂;第三,自主学习是可持续发展生成式学习的内动力。深刻把握AIGC技术中的艺术设计原理及其赋能智慧教学的耦合机制,让AIGC技术成为智慧教学设计的重要助力。 展开更多
关键词 aIGC生成式学习 智慧教学设计 plS—SEM模型 梅耶多媒体学习理论
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实时图像质心检测算法设计及其FPGA实现
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作者 张驾祥 谭会生 《湖南城市学院学报(自然科学版)》 CAS 2024年第3期63-67,共5页
为了克服通用处理器实现图像质心检测算法时处理速度慢,难以应用于高性能实时计算机视觉和图像处理系统的缺点,采用并行处理、流水线等设计优化技术,并通过现场可编程门阵列(field-programmable gate array,FPGA)设计了一种实时图像质... 为了克服通用处理器实现图像质心检测算法时处理速度慢,难以应用于高性能实时计算机视觉和图像处理系统的缺点,采用并行处理、流水线等设计优化技术,并通过现场可编程门阵列(field-programmable gate array,FPGA)设计了一种实时图像质心检测算法。首先,分析了实时图像质心检测算法,并在MATLAB上对其进行仿真验证;然后,使用处理器系统(processing system,PS)和可编程逻辑(programmable logic,PL)相结合的方式,在ZYNQ SOC FPGA芯片上设计、实现了实时图像质心检测算法;最后,进行了实时图像质心检测的硬件验证。试验结果表明,当采集图像分辨率为1024×768、帧率为60时,该设计能够正确实时地计算并标定图像的质心。 展开更多
关键词 图像质心检测 图像腐蚀膨胀 图像边缘检测 HU不变矩 PS%plUS%pl结构 FPGa
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Characteristics of laser-induced breakdown spectroscopy of liquid slag
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作者 董长言 于洪霞 +4 位作者 孙兰香 李洋 刘修业 周平 黄少文 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期86-93,共8页
Rapid online analysis of liquid slag is essential for optimizing the quality and energy efficiency of steel production. To investigate the key factors that affect the online measurement of refined slag using laser-ind... Rapid online analysis of liquid slag is essential for optimizing the quality and energy efficiency of steel production. To investigate the key factors that affect the online measurement of refined slag using laser-induced breakdown spectroscopy(LIBS), this study examined the effects of slag composition and temperature on the intensity and stability of the LIBS spectra. The experimental temperature was controlled at three levels: 1350℃, 1400℃, and 1450℃. The results showed that slag composition and temperature significantly affected the intensity and stability of the LIBS spectra. Increasing the Fe content and temperature in the slag reduces its viscosity, resulting in an enhanced intensity and stability of the LIBS spectra. Additionally, 42 refined slag samples were quantitatively analyzed for Fe, Si, Ca, Mg, Al, and Mn at 1350℃, 1400℃, and 1450℃.The normalized full spectrum combined with partial least squares(PLS) quantification modeling was used, using the Ca Ⅱ 317.91 nm spectral line as an internal standard. The results show that using the internal standard normalization method can significantly reduce the influence of spectral fluctuations. Meanwhile, a temperature of 1450℃ has been found to yield superior results compared to both 1350℃ and 1400℃, and it is advantageous to conduct a quantitative analysis of the slag when it is in a “water-like” state with low viscosity. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) SLaG temperature COMPOSITION VISCOSITY internal standard normalization partial least squares(plS)
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Defects evolution in n-type 4H-SiC induced by electron irradiation and annealing
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作者 Huifan Xiong Xuesong Lu +5 位作者 Xu Gao Yuchao Yan Shuai Liu Lihui Song Deren Yang Xiaodong Pi 《Journal of Semiconductors》 EI CAS CSCD 2024年第7期77-83,共7页
Radiation damage produced in 4H-SiC by electrons of different doses is presented by using multiple characterization techniques. Raman spectra results indicate that SiC crystal structures are essentially impervious to ... Radiation damage produced in 4H-SiC by electrons of different doses is presented by using multiple characterization techniques. Raman spectra results indicate that SiC crystal structures are essentially impervious to 10 Me V electron irradiation with doses up to 3000 kGy. However, irradiation indeed leads to the generation of various defects, which are evaluated through photoluminescence(PL) and deep level transient spectroscopy(DLTS). The PL spectra feature a prominent broad band centered at 500 nm, accompanied by several smaller peaks ranging from 660 to 808 nm. The intensity of each PL peak demonstrates a linear correlation with the irradiation dose, indicating a proportional increase in defect concentration during irradiation. The DLTS spectra reveal several thermally unstable and stable defects that exhibit similarities at low irradiation doses.Notably, after irradiating at the higher dose of 1000 kGy, a new stable defect labeled as R_(2)(Ec-0.51 eV) appeared after annealing at 800 K. Furthermore, the impact of irradiation-induced defects on SiC junction barrier Schottky diodes is discussed. It is observed that high-dose electron irradiation converts SiC n-epilayers to semi-insulating layers. However, subjecting the samples to a temperature of only 800 K results in a significant reduction in resistance due to the annealing out of unstable defects. 展开更多
关键词 4H-SIC deep level transient spectroscopy(DLTS) photoluminescence(pl) DEFECTS
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A process monitoring method for autoregressive-dynamic inner total latent structure projection
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作者 CHEN Yalin KONG Xiangyu LUO Jiayu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1326-1336,共11页
As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decompos... As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decomposition of the input space by DiPLS,there are false alarms in the actual industrial process during fault detection.To address the above problems,a dynamic modeling method based on autoregressive-dynamic inner total PLS(AR-DiTPLS)is proposed.The method first uses the regression relation matrix to decompose the input space orthogonally,which reduces useless information for the predic-tion output in the quality-related dynamic subspace.Then,a vector autoregressive model(VAR)is constructed for the predic-tion score to separate dynamic information and static informa-tion.Based on the VAR model,appropriate statistical indicators are further constructed for online monitoring,which reduces the occurrence of false alarms.The effectiveness of the method is verified by a Tennessee-Eastman industrial simulation process and a three-phase flow system. 展开更多
关键词 dynamic characteristic fault detection feature extraction process monitoring projection to latent structure(plS) quality-related spatial partitioning
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Lattice Boltzmann method formulation for simulation of thermal radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determination
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作者 M.NEMATI M.SEFID +1 位作者 A.KARIMIPOUR A.J.CHAMKHA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1085-1106,共22页
The simultaneous investigation on the parameters affecting the flow of electrically conductive fluids such as volumetric radiation,heat absorption,heat generation,and magnetic field(MF)is very vital due to its existen... The simultaneous investigation on the parameters affecting the flow of electrically conductive fluids such as volumetric radiation,heat absorption,heat generation,and magnetic field(MF)is very vital due to its existence in various sectors of industry and engineering.The present research focuses on mathematical modeling to simulate the cooling of a hot component through power-law(PL)nanofluid convection flow.The temperature reduction of the hot component inside a two-dimensional(2D)inclined chamber with two different cold wall shapes is evaluated.The formulation of the problem is derived with the lattice Boltzmann method(LBM)by code writing via the FORTRAN language.The variables such as the radiation parameter(0–1),the Hartmann number(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the Rayleigh number(103–105),the imposed MF angle(0°–90°),the chamber inclination angle(−90°–90°),and the cavity cold wall shape(smooth and curved)are investigated.The findings indicate that the presence of radiation increases the mean Nusselt number value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,respectively.In most cases,the presence of nanoparticles improves the heat transfer(HT)rate,especially in the cases where thermal conduction dominates convection.There is the lowest cooling performance index and MF effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this numerical research. 展开更多
关键词 thermal performance analysis heat absorption/generation power-law(pl)al_(2)O_(3)nanofluid magnetohydrodynamics natural convection volumetric radiation inclined cavity
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