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Effect of Mode of Auxin Application on Rooting and Bud Break of Shea Tree (Vitellaria paradoxa) Cuttings 被引量:1
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作者 Moses Okao Lawrence Ogwal +3 位作者 Gloria Mutoni Samuel Oyuko Alip John Bosco Lamoris Okullo Clement Akais Okia 《American Journal of Plant Sciences》 2016年第15期2199-2208,共10页
Vegetative propagation by stem cutting is an important technique applied for agricultural production where rooting success is one of the major aspects. A study to assess the effects of mode of application of rooting h... Vegetative propagation by stem cutting is an important technique applied for agricultural production where rooting success is one of the major aspects. A study to assess the effects of mode of application of rooting hormones (IBA) on adventitious root formation of V. paradoxa stem cuttings was conducted. Accordingly, four application methods were investigated in a 4 × 3 factorial experiment using a Completely Randomized Design (CRD). The application methods were: 24-hour extended soak, foliar spraying, basal quick dip and delayed IBA application method. Thus, the parameters used to determine rooting success were mean root length and root number. The effect of these application methods on occurrence of bud break was also considered. On the whole, root length was observed to be a function of IBA concentration, whereby root length increased significantly (P ≤ 0.05) with an increment in IBA concentration. Stem cuttings subjected to 24-h extended soak at 100 ppm rooted best (59.5% ± 8.33%), where as foliar sprayed stem cuttings exhibited the worst rooting success (11.9 ± 3.06 - 23.8% ± 4.16%). Bud break appeared to decrease with increasing IBA concentration and delaying IBA application enhanced rooting percentage of the quick dip method by 7.1%, 9.5% and 11.9% at 2500 ppm, 3500 ppm and 4500 ppm, respectively. The extended soak method of IBA application at 80 ppm shows potential for large scale production of V. paradoxa through stem cuttings. 展开更多
关键词 IBA mode of Application Shea tree Extended Soak Method Bud Break
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Tree failure modes influenced by the characteristics of tree and its root distribution caused by debris flows
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作者 CHEN Xiaoqing JIN Ke +3 位作者 WANG Chenyuan LIU Haitao ZHAO Wanyu CHEN Jiangang 《Journal of Mountain Science》 SCIE CSCD 2024年第12期3986-4000,共15页
Forests play an important role in controlling the formation and movement processes of debris flows.They contribute to soil stabilization,regulation of soil water content,and act as robust structures impeding the downs... Forests play an important role in controlling the formation and movement processes of debris flows.They contribute to soil stabilization,regulation of soil water content,and act as robust structures impeding the downstream progression of debris flows.On the positive side,trees,to some extent,can intercept debris flows and effectively mitigate their velocity by increasing flow resistance.On the negative side,trees may suffer damage from debris-flow hazards,characterized by the generation of substantial quantities of wood fragments and consequential ramifications such as river channel blockage,resulting in backwater rise.In extreme cases,this blockage collapse can lead to instantaneous discharge amplification,thereby adversely impacting urban safety and impeding sustainable development.Therefore,in order to grasp the effects of tree characteristics on tree failure modes,the tree failure modes and corresponding parameters,diameters at breast height(DBH)and root-soil plate size,were identified and recorded through the post-event field investigation in Keze Gully,a region prone to debrisflow events in Sichuan,China,respectively.To investigate the impact of spatial variability in tree root distribution on tree failure modes,the root crosssectional area ratio(RAR),root density(RD),root length density(RLD)and soil detachment rate(SDR)were obtained.The findings indicated that:(1)Tree characteristics reflect the interactions of debris flows and trees,and influence the tree failure modes ultimately.The root distribution characteristics influence the size and shape of the root-soil plate to affect the resistance of trees.(2)Compared to burial and abrasion,stem breakage and overturning are the predominant modes of tree failure in debris-flow hazards.Trees with a smaller DBH primarily experience stem breakage and bending,and trees with a larger DBH mostly experience overturning.(3)The root-soil plate shapes of overturned trees,affected by the root architecture and root growth range,are generally semielliptical or semicircular,and the horizontal and vertical radii increase with DBH,but the correlation between the root-soil plate’s breadth-depth ratio and DBH is low.(4)The biomass and RAR decrease with distance.The RAR distribution exhibit the order of upslope direction>downslope direction>lateral direction.The coarse root biomass significantly increases with DBH,but no clear trend in fine root biomass.(5)The roots can significantly enhance the soil erosion resistance,but the erosion resistance of coarse roots is not as significant as that of fine roots.The erosion resistance increases with DBH,and follows the order of upslope direction>downslope direction>lateral direction.The results could provide new insights into the influences of tree and root distribution characteristics on tree failure modes during debris flows. 展开更多
关键词 Debris flows tree characteristics Root distribution characteristics tree failure modes Forestation
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Parallelized Hashing via <i>j</i>-Lanes and <i>j</i>-Pointers Tree Modes, with Applications to SHA-256
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作者 Shay Gueron 《Journal of Information Security》 2014年第3期91-113,共23页
j-lanes tree hashing is a tree mode that splits an input message into?j?slices, computes?j?independent digests of each slice, and outputs the hash value of their concatenation.?j-pointers tree hashing is a similar tre... j-lanes tree hashing is a tree mode that splits an input message into?j?slices, computes?j?independent digests of each slice, and outputs the hash value of their concatenation.?j-pointers tree hashing is a similar tree mode that receives, as input,?j?pointers to?j?messages (or slices of a single message), computes their digests and outputs the hash value of their concatenation. Such modes expose parallelization opportunities in a hashing process that is otherwise serial by nature. As a result, they have a performance advantage on modern processor architectures. This paper provides precise specifications for these hashing modes, proposes appropriate IVs, and demonstrates their performance on the latest processors. Our hope is that it would be useful for standardization of these modes. 展开更多
关键词 tree mode HASHING SHA-256 SIMD Architecture Advanced Vector Extensions Architectures AVX AVX2
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A <i>j</i>-Lanes Tree Hashing Mode and <i>j</i>-Lanes SHA-256
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作者 Shay Gueron 《Journal of Information Security》 2013年第1期7-11,共5页
j-lanes hashing is a tree mode that splits an input message to j slices, computes j independent digests of each slice, and outputs the hash value of their concatenation. We demonstrate the performance advantage of j-l... j-lanes hashing is a tree mode that splits an input message to j slices, computes j independent digests of each slice, and outputs the hash value of their concatenation. We demonstrate the performance advantage of j-lanes hashing on SIMD architectures, by coding a 4-lanes-SHA-256 implementation and measuring its performance on the latest 3rd Generation IntelR CoreTM. For messages whose lengths range from 2 KB to 132 KB, we show that the 4-lanes SHA-256 is between 1.5 to 1.97 times faster than the fastest publicly available implementation that we are aware of, and between ~2 to ~2.5 times faster than the OpenSSL 1.0.1c implementation. For long messages, there is no significant performance difference between different choices of j. We show that the 4-lanes SHA-256 is faster than the two SHA3 finalists (BLAKE and Keccak) that have a published tree mode implementation. Finally, we explain why j-lanes hashing will be faster on the coming AVX2 architecture that facilitates using 256 bits registers. These results suggest that standardizing a tree mode for hash functions (SHA-256 in particular) could be useful for performance hungry applications. 展开更多
关键词 tree mode HASHING SHA-256 SHA3 Competition SIMD Architecture Advanced Vector Extensions Architectures AVX AVX2
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Application Practice of OMO Teaching Mode of"Two Courses,Three Links and Two Main Subjects"Based on the Wisdom Tree Platform
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作者 Chunyan JIA 《Asian Agricultural Research》 2023年第2期68-71,74,共5页
The shared course and flipped course of Modern Educational Technology were constructed and applied based on the wisdom tree platform.The OMO teaching mode of"two courses,three links and two main subjects"was... The shared course and flipped course of Modern Educational Technology were constructed and applied based on the wisdom tree platform.The OMO teaching mode of"two courses,three links and two main subjects"was constructed according to the course teaching practice,and the teaching practice was carried out.The main teaching links and teaching quality assurance system of the mode were expounded and the application effect was analyzed from the three aspects of student evaluation,course performance and course goal achievement value.The problems in the application of the mode were discussed,and some improvement measures were put forward from the aspects of students,teachers and schools. 展开更多
关键词 Wisdom tree platform OMO teaching mode modern educational technology Application
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一种基于CAN-tree快速构建算法 被引量:4
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作者 陈刚 闫英战 刘秉权 《微电子学与计算机》 CSCD 北大核心 2014年第1期76-82,共7页
增量关联挖掘领域是近几年数据挖掘研究的一个热点,而CAN-tree的提出是增量关联挖掘发展的一个重要里程碑.虽然CAN-tree适用于增量关联挖掘,但CAN-tree构建时间长,挖掘效率偏低;针对此问题,提出了一种基于CAN-tree快速构建算法,该算法... 增量关联挖掘领域是近几年数据挖掘研究的一个热点,而CAN-tree的提出是增量关联挖掘发展的一个重要里程碑.虽然CAN-tree适用于增量关联挖掘,但CAN-tree构建时间长,挖掘效率偏低;针对此问题,提出了一种基于CAN-tree快速构建算法,该算法增加基于哈希表的辅助存储结构,用于减少项目的查找时间,从而提高CANtree的构建速度;增加叶子地址表并修改节点结构及改child指针为parent指针,目的是减少剪枝时间和条件模式基的生成时间,从而提高数据挖掘效率.实验结果表明该算法有效. 展开更多
关键词 关联规则 频繁模式 CAN-tree 条件模式
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Load-balancing data distribution in publish/subscribe mode
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作者 李凯 汪芸 +1 位作者 殷奕 袁飞飞 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期428-433,共6页
To improve data distribution efficiency a load-balancing data distribution LBDD method is proposed in publish/subscribe mode.In the LBDD method subscribers are involved in distribution tasks and data transfers while r... To improve data distribution efficiency a load-balancing data distribution LBDD method is proposed in publish/subscribe mode.In the LBDD method subscribers are involved in distribution tasks and data transfers while receiving data themselves.A dissemination tree is constructed among the subscribers based on MD5 where the publisher acts as the root. The proposed method provides bucket construction target selection and path updates furthermore the property of one-way dissemination is proven.That the average out-going degree of a node is 2 is guaranteed with the proposed LBDD.The experiments on data distribution delay data distribution rate and load distribution are conducted. Experimental results show that the LBDD method aids in shaping the task load between the publisher and subscribers and outperforms the point-to-point approach. 展开更多
关键词 data distribution publish/subscribe mode load balance dissemination tree
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医疗失效模式与效应分析在我国医院应用现状分析
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作者 张丹 张欣 +2 位作者 徐仪嘉 李林瑾 刘庭芳 《中国医院》 北大核心 2026年第1期39-43,共5页
目的:通过分析第9~11届全国医院品管圈暨多维工具大会中的HFMEA专场参会案例,了解HFMEA在医院的应用现况,总结相关问题并提出建议。方法:对参会案例进行统计分析和主题归纳,并就HFMEA应用各阶段存在的常见问题进行解析。结果:研究分析了... 目的:通过分析第9~11届全国医院品管圈暨多维工具大会中的HFMEA专场参会案例,了解HFMEA在医院的应用现况,总结相关问题并提出建议。方法:对参会案例进行统计分析和主题归纳,并就HFMEA应用各阶段存在的常见问题进行解析。结果:研究分析了236个HFMEA参会案例,发现其在医院中的应用领域包括药品管理、并发症控制、管路安全管理、转运安全管理、临床标本管理、手术流程管理、疫情防控、跌倒预防、物料管理等领域,主要存在子流程功能与目的描述不足、失效原因分析阶段缺乏决策树的使用等问题。结论:HFMEA是具有前瞻性的风险防控与流程优化工具;下一步可以推动多元主体开展HFMEA应用,提升HFMEA工具使用的规范性,扩大HFMEA工具的应用领域,以及结合其他工具促进质量持续改进。 展开更多
关键词 医院 医疗失效模式与效应分析 危害分数 决策树 应用现况
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果树咸水灌溉:现状、挑战与技术发展前景
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作者 赵桥 马英杰 +3 位作者 辛明亮 艾鹏睿 许源 左顺利 《灌溉排水学报》 2026年第2期8-19,共12页
咸水资源的开发利用已成为缓解干旱区淡水资源匮乏、保障水资源安全的有效途径。随着果树种植面积的扩大,水资源需求日益增加,拓展可利用灌溉水源,特别是咸水资源的合理利用,已成为确保果树产业可持续发展的关键途径。为此,本文系统分... 咸水资源的开发利用已成为缓解干旱区淡水资源匮乏、保障水资源安全的有效途径。随着果树种植面积的扩大,水资源需求日益增加,拓展可利用灌溉水源,特别是咸水资源的合理利用,已成为确保果树产业可持续发展的关键途径。为此,本文系统分析咸水资源在果树灌溉中的应用潜力,评估不同盐度水源对果树生长的影响,重点探讨了咸水灌溉下果树生理特性、渗透调节物质与离子转运及调控措施,鉴于目前咸水灌溉在果树耐盐机理、盐分适应阈值、果树-土壤系统响应机制、咸水灌溉调控技术体系及果树咸水灌溉的开发前景与潜在风险研究不足,建议加强不同果树长期咸水灌溉耐盐机制及咸水灌溉技术体系的综合研究,以实现咸水资源的科学高效利用,为绿色节水农业和咸水资源高效安全利用提供理论依据与技术支撑。 展开更多
关键词 咸水灌溉 果树 生理响应 灌溉模式 生态效应
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融合变分模态分解与Crossformer的超短期风电功率预测
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作者 康梦淇 史加荣 《西安工业大学学报》 2026年第1期131-140,共10页
为解决传统超短期风电功率预测未考虑多元特征的跨维度依赖性问题,提出了一种结合变分模态分解(VMD)与Crossformer的混合模型。根据梯度提升回归树筛选出对风电功率影响较大的特征,并对所选特征与风电功率分别执行VMD;对VMD分解后的所... 为解决传统超短期风电功率预测未考虑多元特征的跨维度依赖性问题,提出了一种结合变分模态分解(VMD)与Crossformer的混合模型。根据梯度提升回归树筛选出对风电功率影响较大的特征,并对所选特征与风电功率分别执行VMD;对VMD分解后的所有子序列,建立Crossformer模型,以实现跨时间与维度的依赖性;将各子序列的预测值进行叠加,得到最终的预测结果。实验表明提出的VMD-Crossformer模型在各项预测评价指标上均取得最优,四个数据集上平均的RMSE、MAE、MAPE至少降低25.3%、27.1%、25.4%,而R2至少提高3.4%。 展开更多
关键词 风电功率预测 变分模态分解 Crossformer模型 跨维度依赖性 梯度提升回归树
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樟子松人工林二代林更新模式及树种选择
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作者 王国晨 《防护林科技》 2026年第1期38-41,共4页
樟子松(Pinus sylvestris var.mongolica)人工林的衰退与死亡是多种因素共同作用的结果,其中土壤养分失衡是主要因素之一。以科尔沁沙地樟子松人工林二代林更新为背景,选取14种主要造林树种,通过林地土壤养分分析,评估不同树种对土壤养... 樟子松(Pinus sylvestris var.mongolica)人工林的衰退与死亡是多种因素共同作用的结果,其中土壤养分失衡是主要因素之一。以科尔沁沙地樟子松人工林二代林更新为背景,选取14种主要造林树种,通过林地土壤养分分析,评估不同树种对土壤养分的提升效应。结果表明:2种模式的混交林综合指数分别为1.13和0.96,均高于樟子松纯林(0.51);混交林的肥力显著高于纯林。混交模式是科尔沁沙地樟子松人工林迹地更新的理想模式,树种主要以樟子松、彰武松(Pinus densiflora var.zhangwuensis)和元宝枫(Acer truncatum)为主。 展开更多
关键词 樟子松人工林 更新模式 树种选择
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Effects of arrangement of surge-root irrigation emitters on growth,yield and water use efficiency of apple trees 被引量:5
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作者 LI Zhongjie FEI Liangjun +4 位作者 HAO Kun LIU Teng CHEN Nanshu ZHANG Quanju HUANG Deliang 《排灌机械工程学报》 EI CSCD 北大核心 2020年第7期713-719,共7页
Six-year old apple trees were selected for field experiment.The objective of this study was to obtain the reasonable arrangement of surge-root irrigation emitters in apple orchards.There were three factors:the buried ... Six-year old apple trees were selected for field experiment.The objective of this study was to obtain the reasonable arrangement of surge-root irrigation emitters in apple orchards.There were three factors:the buried depth H(25,40,55 cm),the horizontal distance L(30,40,60 cm)between the emitters and the trunk of the experimental tree,and the number of the irrigation emitters N(1,2,4).The effect of the arrangement of surge-root irrigation emitters on the growth,yield and irrigation water use efficiency(IWUE)of apple trees were studied in Northern Shaanxi where the irrigation quota takes 60%-75%of the field water capacity.The results showed that the arrangement of emitters for surge-root irrigation had a significant effect on apple tree yield and IWUE,especially,the yield and IWUE reached 28388.17 kg/hm2 and 16.83 kg/m3 in treatment T3,respectively.At the same L and N levels(T1,T2,and T3),the yield and IWUE in treatment T3 were the highest,and the yields in treatments T1 and T2 were decreased by 26.22%and 31.48%,while IWUE is reduced by14.02%and 18.12%compared with T3,respectively.At the same H and N levels(T3,T4,and T5),the yield and IWUE of apple trees were decreased with increasing L level.Especially,when L was 30 cm(T3),the yield and IWUE were the highest.The same L and H levels(T3,T6,and T7)could promote the growth of apple trees when N was 2(T3).Compared with treatment T3,it was found that the increment of new shoots was decreased by 8.07%-18.71%,and the fruit diameter was decreased by 5.41%-9.11%.Therefore,two emitters should be arranged symmetrically on both sides of an apple tree,each was buried at a 40 cm depth and 30 cm away from the trunk of the tree to effectively improve the yield and IWUE of the apple tree in mountainous areas in Northern Shaanxi. 展开更多
关键词 irrigation emitters surge-root irrigation apple trees arrangement modes YIELD irrigation water use efficiency
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Automatic Classification of Cardiac Arrhythmias Based on Hybrid Features and Decision Tree Algorithm 被引量:5
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作者 Santanu Sahoo Asit Subudhi +1 位作者 Manasa Dash Sukanta Sabut 《International Journal of Automation and computing》 EI CSCD 2020年第4期551-561,共11页
Accurate classification of cardiac arrhythmias is a crucial task because of the non-stationary nature of electrocardiogram(ECG)signals.In a life-threatening situation,an automated system is necessary for early detecti... Accurate classification of cardiac arrhythmias is a crucial task because of the non-stationary nature of electrocardiogram(ECG)signals.In a life-threatening situation,an automated system is necessary for early detection of beat abnormalities in order to reduce the mortality rate.In this paper,we propose an automatic classification system of ECG beats based on the multi-domain features derived from the ECG signals.The experimental study was evaluated on ECG signals obtained from the MIT-BIH Arrhythmia Database.The feature set comprises eight empirical mode decomposition(EMD)based features,three features from variational mode decomposition(VMD)and four features from RR intervals.In total,15 features are ranked according to a ranker search approach and then used as input to the support vector machine(SVM)and C4.5 decision tree classifiers for classifying six types of arrhythmia beats.The proposed method achieved best result in C4.5 decision tree classifier with an accuracy of 98.89%compared to cubic-SVM classifier which achieved an accuracy of 95.35%only.Besides accuracy measures,all other parameters such as sensitivity(Se),specificity(Sp)and precision rates of 95.68%,99.28%and 95.8%was achieved better in C4.5 classifier.Also the computational time of 0.65 s with an error rate of 0.11 was achieved which is very less compared to SVM.The multi-domain based features with decision tree classifier obtained the best results in classifying cardiac arrhythmias hence the system could be used efficiently in clinical practices. 展开更多
关键词 Electrocardiogram(ECG) cardiac arrhythmias empirical mode decomposition(EMD) variational mode decomposition(VMD) hybrid features decision tree classifier
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HRM: H-tree based reconfiguration mechanism in reconfigurable homogeneous PE array 被引量:7
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作者 Junyong Deng Lin Jiang +5 位作者 Yun Zhu Xiaoyan Xie Xinchuang Liu Feilong He Shuang Song L.K.John 《Journal of Semiconductors》 EI CAS CSCD 2020年第2期42-50,共9页
In order to accommodate the variety of algorithms with different performance in specific application and improve power efficiency,reconfigurable architecture has become an effective methodology in academia and industr... In order to accommodate the variety of algorithms with different performance in specific application and improve power efficiency,reconfigurable architecture has become an effective methodology in academia and industry.However,existing architectures suffer from performance bottleneck due to slow updating of contexts and inadequate flexibility.This paper presents an H-tree based reconfiguration mechanism(HRM)with Huffman-coding-like and mask addressing method in a homogeneous processing element(PE)array,which supports both programmable and data-driven modes.The proposed HRM can transfer reconfiguration instructions/contexts to a particular PE or associated PEs simultaneously in one clock cycle in unicast,multicast and broadcast mode,and shut down the unnecessary PE/PEs according to the current configuration.To verify the correctness and efficiency,we implement it in RTL synthesis and FPGA prototype.Compared to prior works,the experiment results show that the HRM has improved the work frequency by an average of 23.4%,increased the updating speed by 2×,and reduced the area by 36.9%;HRM can also power off the unnecessary PEs which reduced 51%of dynamic power dissipation in certain application configuration.Furthermore,in the data-driven mode,the system frequency can reach 214 MHz,which is 1.68×higher compared with the programmable mode. 展开更多
关键词 H-tree based reconfiguration mechanism(HRM) Huffman-coding-like addressing programmable mode data-driven mode homogeneous PE array
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Assessment Method for the Reliability of Power Transformer Based on Fault-tree Analysis 被引量:15
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作者 WANG You-yuan ZHOU Jing-jing CHEN Wei-gen DU Lin CHEN Ren-gang 《高电压技术》 EI CAS CSCD 北大核心 2009年第3期514-520,共7页
关键词 电力变压器 供电系统 故障树分析 失效模式
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HFMEA和决策树模型在医疗机构多重耐药菌风险评估中的应用
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作者 季淑艳 刘巍 +1 位作者 王得顺 蒯婧婧 《武警医学》 2025年第10期848-853,共6页
目的 探索医疗保健失效模式与效应分析(HFMEA)和决策树模型在医疗机构多重耐药菌感染(MDRO)管理中的应用与评价。方法 运用HFMEA风险评估法和决策树分析筛选出2023-06至2023-12江苏省盐城市第三人民医院MDRO的高风险因素,于2024年1~6月... 目的 探索医疗保健失效模式与效应分析(HFMEA)和决策树模型在医疗机构多重耐药菌感染(MDRO)管理中的应用与评价。方法 运用HFMEA风险评估法和决策树分析筛选出2023-06至2023-12江苏省盐城市第三人民医院MDRO的高风险因素,于2024年1~6月针对性地采用改进干预措施并落实整改,分析比较干预前和干预后效果。结果 从48项失效模式中共筛选出7项需要改善的高风险模式进行干预,通过对比干预前后MDRO管理指标,结果发现,院感综合目标考核达标率干预前后分别为81.6%和92.1%,差异无统计学意义。干预后其余6项指标:科室MDRO感染风险评估制度知晓率、科室MDRO风险评估执行率、MDRO感染患者有效隔离率、临床医师抗菌药物培训考试合格率、抗菌药物医嘱点评合格率、科室未执行MDRO防控措施扣分率与干预前比较,差异均有统计学意义(P<0.05)。结论 HFMEA与决策树模型作为管理工具,对评估医疗机构内MDRO感染风险方面有效,能够优化MDRO的管理流程,促进医疗、护理及药学等部门管理措施的完善,有效防止MDRO在医院内部传播暴发。 展开更多
关键词 失效模式与效应分析 决策树分析 多重耐药菌 院内感染
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基于FMEA和DFTA的电动机控制器可靠性评估 被引量:3
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作者 董慧芬 谢辉 徐海 《航空动力学报》 北大核心 2025年第9期461-471,共11页
电动机控制器作为电动航空器动力装置的重要组成部分,其可靠性与航空器的飞行安全息息相关,因此对控制器的可靠性进行评估是控制器设计过程中的关键环节之一。为了提高对控制器可靠性的评估的准确性,提出一种基于失效模式及其影响分析... 电动机控制器作为电动航空器动力装置的重要组成部分,其可靠性与航空器的飞行安全息息相关,因此对控制器的可靠性进行评估是控制器设计过程中的关键环节之一。为了提高对控制器可靠性的评估的准确性,提出一种基于失效模式及其影响分析与动态故障树分析结合的电动机控制器可靠性分析方法,在关注控制器故障模式的同时也对其动态特性进行分析,尽可能全面地评估控制器可靠性。以某四旋翼电动垂直起降航空器电推进系统的电动机控制器为分析案例,结合电动机控制器拓扑结构分析其故障模式并通过动态故障树计算得到其失效概率为1.18×10-6,验证了该方法的可行性和有效性,为电动航空器电动机控制器的可靠性评估提供了一种可参考的方法。 展开更多
关键词 电动机控制器 可靠性 失效模式及其影响分析 动态故障树 电推进
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豪华邮轮吊舱推进器可靠性建模与评估
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作者 董小伟 韦昊函 +2 位作者 张雪琴 严新平 欧阳武 《船海工程》 北大核心 2025年第5期110-115,共6页
为提高豪华邮轮吊舱推进器的服役可靠性和安全性,降低维修成本,在分析吊舱推进器结构及工作特点的基础上,对推进器子模块及关键零部件进行可靠性建模与评估研究,开展故障树分析(FTA)及失效模式和效应分析(FMEA),提取涉及吊舱推进系统潜... 为提高豪华邮轮吊舱推进器的服役可靠性和安全性,降低维修成本,在分析吊舱推进器结构及工作特点的基础上,对推进器子模块及关键零部件进行可靠性建模与评估研究,开展故障树分析(FTA)及失效模式和效应分析(FMEA),提取涉及吊舱推进系统潜在故障模式及其原因,提出吊舱推进器典型故障检测与识别方法,分析典型故障对吊舱推进系统运行性能的影响。利用风险顺序数(RPN)进行吊舱推进器失效风险量化评估,确定优先的改进方向。通过吊舱推进器的可靠性建模和评估,提出系统可靠性及风险优先级管理系统方法,明确不同故障模式的风险等级,提高维修效率,从而优化维护策略,为设计、制造和调试阶段的系统优化提供科学依据和参考。 展开更多
关键词 吊舱推进器系统 故障树分析 失效模式和效应分析 风险顺序数
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因素变化过程中的系统故障模式动态识别方法研究 被引量:1
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作者 崔铁军 李莎莎 王鑫阳 《重庆理工大学学报(自然科学)》 北大核心 2025年第3期51-56,共6页
为弥补通过绝对故障数量方式识别系统故障模式的不足,以因素变化过程中的故障数量变化为基础,提出系统故障模式动态识别方法。该方法以空间故障树的特征函数和故障分布提供故障数据变化特征;以集对分析的联系数表达识别的确定性和不确... 为弥补通过绝对故障数量方式识别系统故障模式的不足,以因素变化过程中的故障数量变化为基础,提出系统故障模式动态识别方法。该方法以空间故障树的特征函数和故障分布提供故障数据变化特征;以集对分析的联系数表达识别的确定性和不确定性计算联系度,进而计算动态识别度完成故障样本模式的动态识别。论述了系统故障模式动态识别方法的可行性。给出了单一因素和多因素联合影响下的动态识别流程。通过电气系统故障标准模式对故障样本模式进行识别,证明了方法的有效性。为系统故障模式动态识别提供了新的方法。 展开更多
关键词 安全系统工程 空间故障树 特征函数 联系数 故障模式 动态识别
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面向果树机械疏花的图像识别分析与试验
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作者 迟俊康 张倩 +4 位作者 李胜多 胡彩旗 韩业超 刘栋宇 邓鹏 《青岛农业大学学报(自然科学版)》 2025年第3期222-226,共5页
为改进传统果园疏花机械,在疏花机中增加了图像识别功能,对采集的果树图像进行RGB色彩模式预处理,提高花朵部分像素相对亮度,减少图像噪点数量。采用YOLOv5s模型对预处理图像进行学习,将图像部分裁剪并重新进行单元化矩阵卷积,以优化模... 为改进传统果园疏花机械,在疏花机中增加了图像识别功能,对采集的果树图像进行RGB色彩模式预处理,提高花朵部分像素相对亮度,减少图像噪点数量。采用YOLOv5s模型对预处理图像进行学习,将图像部分裁剪并重新进行单元化矩阵卷积,以优化模型。试制果园疏花机试验平台并在苹果果园中进行测试,花朵识别率为73%,花朵覆盖率为90%,满足果树机械疏花工作要求。 展开更多
关键词 疏花 果树图像 RGB色彩模式 深度学习
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