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Sensory Evaluation of Freeze-Dried Facial Mask and Analysis of User Profile
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作者 Qi Rong Chu LiLing Wang Feifei 《China Detergent & Cosmetics》 CAS 2024年第3期41-49,共9页
To thoroughly understand market opportunity of freeze-dried facial mask and deeply get insight of consumers’usage behavior and needs,evaluate sensory feelings of 10 screened commercial freeze-dried facial mask produc... To thoroughly understand market opportunity of freeze-dried facial mask and deeply get insight of consumers’usage behavior and needs,evaluate sensory feelings of 10 screened commercial freeze-dried facial mask products,group test products according to the differences of sensory attributions via Principal Component Analysis(PCA)and Agglomerative Hierarchical Clustering(AHC),pick up the representative products.Freeze-dried facial mask users evaluate satisfaction degree of picked up products and participate survey of usage behavior/cognition.Analyze consumer data by AHC to get consumer segmentations and their profile.The test results show that,sensory data and consumer data,which is from consumers test of screened representative products by performing PCA and AHC on sensory data,can be verified mutually.It is helpful to understand the needs of consumer segmentations and reason to buy by combining sensory data and consumer test. 展开更多
关键词 freeze-dried facial mask sensory evaluation consumer satisfaction evaluation PCA AHC user profile
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基于改进AdvSemiSeg的半监督遥感影像作物制图方法
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作者 翟雪东 韩文霆 +3 位作者 马伟童 崔欣 李广 黄沈锦 《农业机械学报》 EI CAS CSCD 北大核心 2024年第8期196-204,共9页
作物精准遥感制图对于农业资源调查与管理具有重要意义。深度学习为实现精准高效作物制图提供了技术支持。为了缓解深度学习对标记样本的依赖,本文提出了一种改进AdvSemiSeg的半监督遥感影像作物制图方法。所提方法引入STMF-DeepLabv3+... 作物精准遥感制图对于农业资源调查与管理具有重要意义。深度学习为实现精准高效作物制图提供了技术支持。为了缓解深度学习对标记样本的依赖,本文提出了一种改进AdvSemiSeg的半监督遥感影像作物制图方法。所提方法引入STMF-DeepLabv3+作为对抗学习中的生成网络,通过Swin Transformer(ST)和多尺度特征融合(Multi-scale fusion, MF)模块提高生成网络特征编码能力和语义表达能力,改善遥感影像作物分割效果;此外,在判别网络中引入通道注意力(Efficient channel attention, ECA)模块,对不同通道特征图的表征信息进行自适应学习,增强判别网络对不同通道特征的感知能力。模型训练过程中,判别网络为生成网络提供高质量的伪标签和对抗损失,有效提高生成网络的泛化能力。采用所提方法与几种先进的半监督语义分割方法对内蒙古河套灌区遥感影像种植信息进行提取,本文方法性能最优。 展开更多
关键词 遥感 作物制图 半监督学习 生成对抗网络 多尺度特征融合 通道注意力
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基于事件触发的奇异semi-Markov跳变系统的有限时间控制
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作者 刘雪华 嵇小辅 《控制工程》 CSCD 北大核心 2024年第6期1123-1129,共7页
为减少不必要的网络资源传输,解决实际复杂系统的有限时间问题,提出一种基于事件触发方案的奇异semi-Markov跳变系统的有限时间控制器设计方法。在事件触发方案下,用系统的时滞表示网络诱导时延,闭环系统可以建模为一个时滞系统。首先,... 为减少不必要的网络资源传输,解决实际复杂系统的有限时间问题,提出一种基于事件触发方案的奇异semi-Markov跳变系统的有限时间控制器设计方法。在事件触发方案下,用系统的时滞表示网络诱导时延,闭环系统可以建模为一个时滞系统。首先,通过构造合适的Lyapunov-Krasovskii泛函,以严格矩阵不等式的形式给出充分条件,以使事件触发方案下的闭环系统正则、无脉冲、随机有限时间有界;然后,通过求解矩阵不等式,得到状态反馈控制器的参数;最后,给出一个数值示例,通过仿真证明所提方法的有效性。 展开更多
关键词 奇异半马尔可夫跳变系统 事件触发方案 有限时间稳定 线性矩阵不等式
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Estimating the Drought-Induced Yield Loss for Winter Wheat in a Semi-Arid Region of the Southern United States Using a Drought Index
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作者 Prem Woli Qingwu Xue +2 位作者 Gerald R. Smith Charles R. Long Francis M. Rouquette Jr. 《Agricultural Sciences》 2024年第8期812-829,共18页
The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This regio... The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This region is prone to drought and is projected to experience a drier climate. Droughts that coincide with the critical phenological phases of a crop can be remarkably costly. Although drought cannot be prevented, its losses can be minimized through mitigation measures if it is predicted in advance. Predicting yield loss from an imminent drought is an important need of stakeholders. One way to fulfill this need is using an agricultural drought index, such as the Agricultural Reference Index for Drought (ARID). Being plant physiology-based, ARID can represent drought-yield relationships accurately. This study developed an ARID-based yield model for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to water stress. The reasonable values of the drought sensitivity coefficients of the yield model indicated that it could reflect the phenomenon of water stress decreasing the winter wheat yields in this region reasonably. The values of the various metrics used to evaluate the model, including Willmott Index (0.86), Nash-Sutcliffe Index (0.61), and percentage error (26), indicated that the yield model performed fairly well at predicting the drought-induced yield loss for winter wheat. The yield model may be useful for predicting the drought-induced yield loss for winter wheat in the study region and scheduling irrigation allocation based on phenological phase-specific drought sensitivity. 展开更多
关键词 ARID DROUGHT Drought index Growth-stage Model Phenological-Phase Prediction semi-ARID Wheat Yield
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Reversible Semi-Fragile Watermarking Technique for Integrity Control of Relational Database
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作者 Ali Hamadou Abdoul Aziz Issaka Hassane +1 位作者 Lanciné Camara Harouna Naroua 《Engineering(科研)》 2024年第9期309-323,共15页
Reversible watermarking schemes for relational database are usually classified into two groups: robust schemes and fragile schemes. The main limitation of existing reversible fragile methods is that they cannot differ... Reversible watermarking schemes for relational database are usually classified into two groups: robust schemes and fragile schemes. The main limitation of existing reversible fragile methods is that they cannot differentiate between legal and malicious modifications. In this paper, we introduce a novel lossless semi-fragile scheme based on prediction-error expansion for content protection of relational database. In the proposed method, all attributes in a database relation are first classified according to their sensitivity to legitimate updates. Then, the watermark is embedded by expanding the prediction error of the two least significant digits of securely selected attributes. At watermark extraction, the proposed method has the ability to fully restore the original data while detecting and localizing tampering. The applicability of our method is demonstrated theoretically and experimentally. 展开更多
关键词 semi-Fragile Watermarking Integrity Control REVERSIBILITY Prediction-Error Expansion
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Decentralized Semi-Supervised Learning for Stochastic Configuration Networks Based on the Mean Teacher Method
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作者 Kaijing Li Wu Ai 《Journal of Computer and Communications》 2024年第4期247-261,共15页
The aim of this paper is to broaden the application of Stochastic Configuration Network (SCN) in the semi-supervised domain by utilizing common unlabeled data in daily life. It can enhance the classification accuracy ... The aim of this paper is to broaden the application of Stochastic Configuration Network (SCN) in the semi-supervised domain by utilizing common unlabeled data in daily life. It can enhance the classification accuracy of decentralized SCN algorithms while effectively protecting user privacy. To this end, we propose a decentralized semi-supervised learning algorithm for SCN, called DMT-SCN, which introduces teacher and student models by combining the idea of consistency regularization to improve the response speed of model iterations. In order to reduce the possible negative impact of unsupervised data on the model, we purposely change the way of adding noise to the unlabeled data. Simulation results show that the algorithm can effectively utilize unlabeled data to improve the classification accuracy of SCN training and is robust under different ground simulation environments. 展开更多
关键词 Stochastic Neural Network Consistency Regularization semi-Supervised Learning Decentralized Learning
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Solution of the Matrix Second Semi-Tensor Product Equation A ∘ l X ∘ l B=C
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作者 Hao Zhang 《Journal of Applied Mathematics and Physics》 2024年第10期3261-3280,共20页
In this paper, the solution of the matrix second semi-tensor product equation A∘lX∘lB=Cis studied. Firstly, the solvability of the matrix-vector second semi-tensor product equation is investigated. At the same time,... In this paper, the solution of the matrix second semi-tensor product equation A∘lX∘lB=Cis studied. Firstly, the solvability of the matrix-vector second semi-tensor product equation is investigated. At the same time, the compatibility conditions, the sufficient and necessary conditions and the specific solution methods for the matrix solution are given. Secondly, we further consider the solvability of the second semi-tensor product equation of the matrix. For each part, several examples are given to illustrate the validity of the results. 展开更多
关键词 Matrix Equation The Second semi-Tensor Product Compatibility Condition Sufficient and Necessary Conditions VECTORIZATION
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Pseudo-Semi-Overlap Functions-Based Fuzzy Rough Sets Applied to Image Edge Extraction
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作者 Ran Yin Minge Chen +2 位作者 Yu Liu Yafei Zhao Jianwei Li 《Journal of Applied Mathematics and Physics》 2024年第7期2347-2366,共20页
As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and furth... As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and further extended for applications in image edge extraction. Firstly, a new clustering function, the pseudo-semi-overlap function, is introduced by eliminating the symmetry and right continuity present in the overlap function. The relaxed nature of this function enhances its applicability in image edge extraction. Secondly, the definitions of (I, PSO)-fuzzy rough sets are provided, using (I, PSO)-fuzzy rough sets, a pair of new fuzzy mathematical morphological operators (IPSOFMM operators) is proposed. Finally, by combining the fuzzy C-means algorithm and IPSOFMM operators, a novel image edge extraction algorithm (FCM-IPSO algorithm) is proposed and implemented. Compared to existing algorithms, the FCM-IPSO algorithm exhibits more image edges and a 73.81% decrease in the noise introduction rate. The outstanding performance of (I, PSO)-fuzzy rough sets in image edge extraction demonstrates their practical application value. 展开更多
关键词 Pseudo-semi-Overlap Functions Fuzzy Rough Set Fuzzy Mathematical Morphology Image Edge Extraction
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SEMI标准在半导体制造设备中的应用 被引量:2
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作者 韦薇 林煦呐 +2 位作者 张帅 谢琼 杨师 《电子工业专用设备》 2023年第2期58-63,共6页
SEMI标准是一项国际通用的半导体行业标准,为研究SEMI标准在半导体制造设备中的应用情况,介绍了SEMI S2半导体设备安全准则、SEMI F47半导体设备电压暂降抗扰度标准并说明了标准的实际应用。分析了SEMI S23半导体设备能源、电力和原料... SEMI标准是一项国际通用的半导体行业标准,为研究SEMI标准在半导体制造设备中的应用情况,介绍了SEMI S2半导体设备安全准则、SEMI F47半导体设备电压暂降抗扰度标准并说明了标准的实际应用。分析了SEMI S23半导体设备能源、电力和原料的使用效率标准、SECS/GEM通讯标准及其研究应用现状;提出了我国半导体产业的快速发展需要加大SEMI标准的普及应用。 展开更多
关键词 半导体制造设备 semi S2标准 semi F47标准
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The protective effect of oleic acid on Lactiplantibacillus plantarum during freeze-drying 被引量:1
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作者 Yongjun Xia Yizhen Wang +6 位作者 Jing Pu Yan Wu Zhiqiang Xiong Xin Song Hui Zhang Lianzhong Ai Guangqiang Wang 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期2355-2361,共7页
Membrane characteristics are determined by the fatty acids composition,which affects survival rates after freeze-drying.However,it is unknown which composition provides the greatest effect.In this study,we found that ... Membrane characteristics are determined by the fatty acids composition,which affects survival rates after freeze-drying.However,it is unknown which composition provides the greatest effect.In this study,we found that the addition of Tween 80 and Tween 20 significantly increased survival rates of Lactiplantibacillus plantarum,which reached a maximum of 93.1%.Conversely,Tween 60 caused a significant decrease.We further found that the difference between the effects of adding Tween 80 and Tween 60 was the change in oleic acid contents.To verify the role of oleic acid,we used CRISPR-Cas9 to knock-out the key synthesis gene cla-er.The survival rates of L.plantarum AR113Δcla-er declined to 5.48%.The addition of oleic acid restored the rates to those of wild type strains.Moreover,the membrane integrity and fl uidity of knockout strains markedly decreased.This is the fi rst confi rmation that Tween 80 or Tween 20 increases the survival rate by increasing the content of oleic acid in the cell membrane.These fi ndings also indicated that oleic acid in cell membranes has a substantial protective effect on L.plantarum during freeze-drying. 展开更多
关键词 freeze-drying Oleic Acid Gene Knockout Lactiplantibacillus plantarum
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基于多核CPU的无锁并行Semi-naive算法 被引量:1
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作者 喻婷 王立松 秦小麟 《计算机科学》 CSCD 北大核心 2023年第6期29-35,共7页
Datalog系统被广泛应用于很多领域,如图数据库、网络和静态程序分析等。在处理海量数据时,基于串行的Datalog求解策略无法充分发挥现有多核处理器的计算性能。针对上述问题,提出一种基于多核CPU的无锁并行Semi-naive算法(Parallel Semi-... Datalog系统被广泛应用于很多领域,如图数据库、网络和静态程序分析等。在处理海量数据时,基于串行的Datalog求解策略无法充分发挥现有多核处理器的计算性能。针对上述问题,提出一种基于多核CPU的无锁并行Semi-naive算法(Parallel Semi-naive, PSN)用于支持Datalog的高效求解。PSN使用B+树索引进行数据划分,将数据分配给不同的线程执行计算,每个分区产生的中间结果元组互不相同,有利于实现计算时无锁的并行。同时提出一种双层哈希表结构来索引中间结果以提高查重的效率,每个线程只在特定的区域执行相关的计算,无需使用锁来防止写冲突。PSN使用任务队列-线程池为空闲线程分配任务,来实现多线程的负载均衡。在KONECT(Koblenz Network Collection)及斯坦福SNAP(Stanford Network Analysis Platform)的公开数据集上的实验结果表明,PSN算法可以优化Datalog规则的查询性能。 展开更多
关键词 DATALOG semi-naive算法 并行 递归规则 负载均衡
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The Delivery of Grand Multiparas in a Semi-Rural Setting: A Cross-Sectional Descriptive Study at the Ayos Locality of Cameroon
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作者 Serge Robert Nyada Cliford E. Ebong +6 位作者 Véronique Mboua Christiane Nsahlai Pascale Mpono Emenguele Michelle Mendoua Junie Metogo Isidore Tompeen Cyrile Claude Noa Ndoua 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第1期74-81,共8页
Introduction: Grand multiparity is a known risk factor for maternal and fetal complications. Materials and Methods: We carried out a cross-sectional descriptive study on the delivery of grand multiparas at the materni... Introduction: Grand multiparity is a known risk factor for maternal and fetal complications. Materials and Methods: We carried out a cross-sectional descriptive study on the delivery of grand multiparas at the maternity of the regional hospital annex of Ayos, a semi-rural locality in the Center region of Cameroon. The study covered the period from January 2012 through December 2020, and the objective was to assess the frequency, the determinants and the outcome of delivery in grand multiparas. Results: We recorded 1384 deliveries and enrolled 137 cases of delivery of grand multiparas. This gives a frequency of grand multipara delivery of 9.89%. The mean age of the women was 34.96 ± 4.45 years. Married parturients accounted for 65% of the cases and 16.8% were HIV positive. Delivery occurred at term in 89.9%. In 35.8%, no antenatal consultation was done. The use of the partograph during labor was reported in 11.7%. Per vaginal delivery was noted in 88.3%, emergency cesarean in 10.2% and elective cesarean in 1.5%. The most frequent maternal complications included post-partum hemorrhage (19.9%), genital tract tears (12.4%), endometritis (9.5%) and surgical wound infection (8.7%). No maternal death was recorded. The mean birth weight of the newborns was 3336.8 ± 550 g. Fetal complications were mostly represented by neonatal infection (20.1%), perinatal death (7.9%) and neonatal asphyxia (9.5%). Conclusion: The frequency of grand multiparous delivery in the semi-rural locality of Ayos, Cameroon, was 9.89%. The mean age of parturients was 38.96 years and the proportion of vaginal delivery was 88.3%. 展开更多
关键词 Grand Multipara Delivery semi Rural Cameroon
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Radar emitter signal recognition method based on improved collaborative semi-supervised learning
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作者 JIN Tao ZHANG Xindong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1182-1190,共9页
Rare labeled data are difficult to recognize by using conventional methods in the process of radar emitter recogni-tion.To solve this problem,an optimized cooperative semi-supervised learning radar emitter recognition... Rare labeled data are difficult to recognize by using conventional methods in the process of radar emitter recogni-tion.To solve this problem,an optimized cooperative semi-supervised learning radar emitter recognition method based on a small amount of labeled data is developed.First,a small amount of labeled data are randomly sampled by using the bootstrap method,loss functions for three common deep learning net-works are improved,the uniform distribution and cross-entropy function are combined to reduce the overconfidence of softmax classification.Subsequently,the dataset obtained after sam-pling is adopted to train three improved networks so as to build the initial model.In addition,the unlabeled data are preliminarily screened through dynamic time warping(DTW)and then input into the initial model trained previously for judgment.If the judg-ment results of two or more networks are consistent,the unla-beled data are labeled and put into the labeled data set.Lastly,the three network models are input into the labeled dataset for training,and the final model is built.As revealed by the simula-tion results,the semi-supervised learning method adopted in this paper is capable of exploiting a small amount of labeled data and basically achieving the accuracy of labeled data recognition. 展开更多
关键词 emitter signal identification time series BOOTSTRAP semi supervised learning cross entropy function homogeniza-tion dynamic time warping(DTW)
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基于PI的Semi-Markovian电力系统事件触发控制设计分析 被引量:1
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作者 吴子弦 成军 +3 位作者 符坚铃 周心雯 谢佳龙 宁全 《广西师范大学学报(自然科学版)》 CAS 北大核心 2023年第5期76-85,共10页
基于PI控制器设计理论,本文对电力系统负荷频率的稳定性问题进行分析,提出改进的事件触发机制,对带有不确定性半马尔可夫跳变参数的电力系统进行数学均值期望处理,整理构建成随采样信号状态变化而自适应调整的闭环系统。考虑随机跳变多... 基于PI控制器设计理论,本文对电力系统负荷频率的稳定性问题进行分析,提出改进的事件触发机制,对带有不确定性半马尔可夫跳变参数的电力系统进行数学均值期望处理,整理构建成随采样信号状态变化而自适应调整的闭环系统。考虑随机跳变多模态下系统中的干扰影响和时滞虚拟延迟,设计模态依赖控制器,结合矩阵叉积不等式和Schur补定理等,对泛函导数积分项进行放缩,将最优值问题转化为解线性矩阵不等式,最终利用Matlab工具箱求解,求出控制增益和事件触发矩阵,给出系统随机稳定性判据,对系统H∞性能指标进行分析。本文所设计方案可以提高通信网络中控制信号的传输率,有效减轻电网信息输送负担,在节约能源的同时还能提高系统的动态性能。 展开更多
关键词 semi-Markovian 电力系统 PI控制 随机稳定性 事件触发机制 负荷频率控制
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中青年缓解期精神分裂症患者社会疏离体验的质性研究 被引量:12
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作者 徐亚南 栗文娟 +3 位作者 赵淑芹 汤语忌 原富强 赵昆朋 《中国全科医学》 北大核心 2024年第9期1088-1094,共7页
背景精神分裂症患者在整个生存期常感知到的较为严重的社会歧视,出现自我疏离或者社会性疏离。目前针对中青年缓解期精神分裂症患者社会疏离方面的研究较少。目的描述中青年缓解期精神分裂症患者社会疏离的体验,旨在为缓解该人群社会疏... 背景精神分裂症患者在整个生存期常感知到的较为严重的社会歧视,出现自我疏离或者社会性疏离。目前针对中青年缓解期精神分裂症患者社会疏离方面的研究较少。目的描述中青年缓解期精神分裂症患者社会疏离的体验,旨在为缓解该人群社会疏离体验制订支持干预方案提供一定的借鉴和参考。方法采用目的抽样法选取18~59岁,曾在新乡医学院第二附属医院住院且出院后愿意继续接受随访的中青年缓解期精神分裂症患者为研究对象,于2022年5—12月通过对受访者进行面对面半结构式深入访谈,并以内容分析法归纳和提炼主题。结果共纳入18名中青年缓解期精神分裂症患者。通过对访谈资料进行分析,共提炼出3个主题和8个亚主题:中青年缓解期精神分裂症患者社会疏离的表现(包括2个亚主题:负性情感体验、期待与行为之间的退缩);中青年缓解期精神分裂症患者社会疏离的主观原因(包括2个亚主题:自我疏离、自我歧视)、中青年缓解期精神分裂症患者社会疏离的客观原因(包括4个亚主题:社会歧视和被动疏离、药物不良反应的影响、精神疾病引起的生活和照护负担加重、缺乏社会支持)。结论中青年缓解期精神分裂症患者由于生理健康受损、心理状况不良、社会支持不足等存在社会疏离,医护人员应加强对该人群的症状管理和心理疏导,政府及社会各界应积极引导对精神疾病的正向认知并给予一定的社会支持;同时强化家庭内部支持,以帮助其重返和适应社会。 展开更多
关键词 精神分裂症 社会疏离 缓解期 中青年 半结构式访谈 质性研究
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专注晶圆及封测高端设备厂商达仕科技隆重亮相SEMICON CHINA 2023
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《中国集成电路》 2023年第8期90-91,共2页
根据SEMI报告,2022年全球半导体制造设备出货金额相较2021的1026亿美元增长5%,创下1076亿美元的历史新高,中国内地连续第三年成为全球最大的半导体设备市场。今年一季度全球半导体设备出货金额达到268亿美元,比去年同期增长9%,是不可多... 根据SEMI报告,2022年全球半导体制造设备出货金额相较2021的1026亿美元增长5%,创下1076亿美元的历史新高,中国内地连续第三年成为全球最大的半导体设备市场。今年一季度全球半导体设备出货金额达到268亿美元,比去年同期增长9%,是不可多得的亮点。SEMI预计,2024年半导体设备市场会重新恢复增长,预计将以15%的增速重新恢复到1000亿美元以上。 展开更多
关键词 半导体设备 半导体制造设备 高端设备 semi 历史新高
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复杂边界条件下半球壳受迫振动响应分析 被引量:1
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作者 庞福振 张明 +2 位作者 高聪 郑嘉俊 李海超 《振动工程学报》 EI CSCD 北大核心 2024年第3期374-383,共10页
基于半解析法求解得到中厚半球壳的稳态振动与瞬态振动响应。基于一阶剪切变形理论推导球壳结构能量表达式,引入Jacobi多项式和傅里叶级数表示半球壳结构的轴向和径向位移,利用Ritz法得到半球壳的稳态振动响应,与有限元法结果对比验证... 基于半解析法求解得到中厚半球壳的稳态振动与瞬态振动响应。基于一阶剪切变形理论推导球壳结构能量表达式,引入Jacobi多项式和傅里叶级数表示半球壳结构的轴向和径向位移,利用Ritz法得到半球壳的稳态振动响应,与有限元法结果对比验证了本文方法的有可行性。在此基础上,对半球壳在不同边界条件、截顶角和壳体厚度下稳态振动与瞬态振动特性规律进行了分析总结。 展开更多
关键词 半球壳 稳态振动 半解析法 瞬态振动
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基于实测数据的半潜式平台贝叶斯模型修正方法研究 被引量:1
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作者 李松 武文华 姚伟岸 《船舶力学》 EI CSCD 北大核心 2024年第2期179-190,共12页
随着半潜式平台的长期海上服役,平台的基本设计参数会发生变化,如仍基于原始设计参数对平台进行分析将影响结果的准确性。本文以半潜式平台服役中易发生变化的基本参数(平台排水量、重心高度和三个自由度回转半径)作为修正参数,以平台... 随着半潜式平台的长期海上服役,平台的基本设计参数会发生变化,如仍基于原始设计参数对平台进行分析将影响结果的准确性。本文以半潜式平台服役中易发生变化的基本参数(平台排水量、重心高度和三个自由度回转半径)作为修正参数,以平台横摇、纵摇和垂荡自由度的方差和波频功率谱密度构建目标函数,建立可依据实测数据的半潜式平台贝叶斯参数修正方法。以我国某半潜式平台实测数据为例,开展平台的参数修正研究,并基于修正后的参数对平台多年一遇环境荷载下的响应进行对比评估。 展开更多
关键词 半潜式平台 原型监测 贝叶斯 参数修正 代理模型
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Features and Patterns of Primipara Delivery in a Cameroon Semi-Rural Area: The Case of Ayos Locality
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作者 Serge Robert Nyada Cliford E. Ebong +7 位作者 Junie Annick Metogo Ntsama Michelle Mendoua Christiane Nsahlai Véronique Mboua Pascale Mpono Emenguele Isidore Tompeen Etienne Belinga Cyrile Claude Noa Ndoua 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第1期64-73,共10页
Introduction: The delivery of a primipara, a woman giving birth for the first time, is challenging and may lead to complications and influence the obstetrical future of a woman. Materials and Methods: We carried out a... Introduction: The delivery of a primipara, a woman giving birth for the first time, is challenging and may lead to complications and influence the obstetrical future of a woman. Materials and Methods: We carried out a cross-sectional and analytical study at the maternity of the regional hospital annex of Ayos, a semi-rural locality in Cameroon, for the period between January 2012 and December 2020. The objective was to determine the frequency and the determinants of primipara delivery. Results: We recruited 440 cases. The frequency of primipara delivery was 31.8%. The ages of the participants ranged from 12 to 35 years with a mean age of 18.01 ± 3.52 years. Single women contributed to 95.5% of cases while 97.5% were unemployed. The delivery occurred at term in 90.2% and 98.4% of pregnancies were singleton. The delivery was vaginal in 91.6%, while caesarean delivery was done in 8.4% (8% emergency and 0.4% elective). The most frequent maternal complications were genital tract tears (15.7%), post-partum hemorrhage (12.5%) and endometritis (2.7%). The birth weight of newborns ranged from 1070 to 4500 g with a mean of 3024.5 ± 511.4 g. The single marital status, a gestational age between 37 and 42 weeks and a birth weight between 1500 g and 2499 g were significantly associated with vaginal delivery. Conclusion: The frequency of primiparous delivery was relatively high (31.8%) in the Ayos semi-rural health district of Cameroon. Major complications associated with delivery included genital tract tears, post-partum hemorrhage, cesarean section and neo-natal infection. 展开更多
关键词 PRIMIPARA Delivery COMPLICATION semi-Rural Cameroon
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Inequalities for Scalar Curvature and Shape Operator of an R-Lightlike Submanifold in Semi-Riemannian Manifold
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作者 Menedore Karimumuryango Domitien Ndayirukiye +2 位作者 Hans-Fotsing Tetsing Gilbert Nibaruta Aboubacar Nibirantiza 《Journal of Applied Mathematics and Physics》 2023年第7期1895-1913,共19页
We establish the links between the lightlike geometry and basics invariants of the associated semi-Riemannian geometry on r-lightlike submanifold and semi-Riemannian constructed from a semi-Riemannian ambient. Then we... We establish the links between the lightlike geometry and basics invariants of the associated semi-Riemannian geometry on r-lightlike submanifold and semi-Riemannian constructed from a semi-Riemannian ambient. Then we establish some basic inequalities, involving the scalar curvature and shape operator on r-lightlike coisotropic submanifold in semi-Riemannian manifold. Equality cases are also discussed. 展开更多
关键词 semi-Riemannian Submanifold SUBMANIFOLD RIGGING Closed Normalization Associated semi-Riemannian Metric
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