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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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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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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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基于多核CPU的无锁并行Semi-naive算法
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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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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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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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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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基于PI的Semi-Markovian电力系统事件触发控制设计分析
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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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Exploring the Potential of Cowpea-Wheat Double Cropping in the Semi-Arid Region of the Southern United States Using the DSSAT Crop Model
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作者 Prem Woli Gerald R. Smith +3 位作者 Charles R. Long Jackie C. Rudd Qingwu Xue Francis M. Rouquette Jr. 《Agricultural Sciences》 CAS 2023年第1期35-57,共23页
Information is limited on the potential of double-cropping cowpea (Vigna unguiculata L.) and wheat (Triticum aestivum L.) in the semiarid region of the southern United States. Using the Decision Support System for Agr... Information is limited on the potential of double-cropping cowpea (Vigna unguiculata L.) and wheat (Triticum aestivum L.) in the semiarid region of the southern United States. Using the Decision Support System for Agrotechnology Transfer (DSSAT) crop model and weather data of 80 years, we assessed the possibility of cowpea-wheat double-cropping in this region for grain purpose as affected by planting date and N application rate. Results showed that the possibility of double-cropping varied from 0% to 65%, depending on the cropping system. The possibility was less with systems comprising earlier planting dates of wheat and later planting dates of cowpea. Results indicated that cowpea-wheat double-cropping could be beneficial only when no N was applied, with wheat planted on October 15 or later. At zero N, the double-crops of cowpea planted on July 15 and wheat planted on November 30 were the most beneficial of all the 72 double-cropping systems studied. With a delay in planting cowpea, the percentage of beneficial double-cropping systems decreased. At N rates other than zero, fallow-wheat monocropping systems were more beneficial than cowpea-wheat double-cropping systems, and the benefit was greater at a higher N rate. At 100 kg N ha<sup>-1</sup>, the monocrop of wheat planted on October 15 was the most beneficial of all the 94 systems studied. Results further showed that fallow-wheat yields increased almost linearly with an increase in N rate from 0 to 100 kg&#8729;ha<sup>-1</sup>. Fallow-wheat grain yields were quadratically associated with planting dates. With an increase in N rate, wheat yields reached the peak with an earlier planting date. Wheat yields produced under monocropping systems were greater than those produced under double-cropping systems for any cowpea planting date. Cowpea yields produced under monocropping systems were greater than those produced under any double-cropping system. The relationship between cowpea grain yields and planting dates was quadratic, with July 1 planting date associated with the maximum yields. 展开更多
关键词 Cover-Crop Cowpea-Wheat DSSAT Double-Crop Model semi-ARID
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The El Niño-Southern Oscillation (ENSO) Effects on Cowpea and Winter Wheat Yields in the Semi-Arid Region of the Southern US
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作者 Prem Woli Gerald R. Smith +1 位作者 Charles R. Long Francis M. Rouquette Jr. 《Agricultural Sciences》 CAS 2023年第2期154-175,共22页
Information is limited on the effects of climate variability on cowpea (Vigna unguiculata L.) and winter wheat (Triticum aestivum L.) yields in the semiarid region of the southern US. Using the Decision Support System... Information is limited on the effects of climate variability on cowpea (Vigna unguiculata L.) and winter wheat (Triticum aestivum L.) yields in the semiarid region of the southern US. Using the Decision Support System for Agrotechnology Transfer (DSSAT) crop model and weather data spanning 81 years, we assessed the impact of El Niño-Southern Oscillation (ENSO) on the grain yields of these crops in the Llano Estacado region of the southern US as affected by cowpea and wheat planting dates and N application rate. Simulated results showed that the El Niño phase of ENSO produced about 30% more yields of mono-cropped cowpea than those produced under the La Niña phase, especially with the cowpeas planted in July. The cowpea yields under El Niño were about 10% more than the 81-year average normal yield, whereas those under La Niña were about 20% less. At the N rates of 0, 50, and 100 kg·ha<sup>−1</sup>, regardless of wheat planting dates, the El Niño years produced, respectively, about 8%, 40%, and 60% higher wheat yields than those produced in the La Niña years, and about 5%, 20%, and 27% more than the 81-year average normal yield. In the La Niña years, the wheat yields at 0, 50, and 100 kg N ha<sup>−1 </sup>were, respectively, about 5%, 15%, and 20% less than the normal yield with similar N levels. The impact of ENSO on wheat yields under cowpea-wheat double-cropping systems was significant, especially for the wheat crops planted on October 15 (October 30) or later following the cowpea crops planted in June (July). At zero N, the mono-cropped wheat yields were not impacted by ENSO due to N limitation. However, the double-cropped wheat yields were impacted by ENSO even when no N fertilizer was applied due to high soil N status caused by N transfer from cowpea stover residues and roots. Results indicated that management strategies need to be attentive to ENSO forecasts and adjust potential planting dates and N application rates with the ENSO phase to avert risks of crop failure and economic loss. 展开更多
关键词 Climate COWPEA DSSAT Double-Crop El Niño ENSO Model semi-Arid Wheat
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Semi-Pre-HPLC与HPLC-MS联用的二维色谱分析系统对代谢相关脂肪性肝病肝线粒体中滇黄精药源成分的检测
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作者 史婷婷 李艳娟 +5 位作者 杨艾 王涛 宋成竹 席建军 姜晓杰 杨兴鑫 《中国医药导报》 CAS 2023年第13期18-22,共5页
目的检测代谢相关脂肪性肝病(MAFLD)肝线粒体中滇黄精药源成分的分布情况。方法24只6周龄雄性SD大鼠采用随机数字表法分为正常组、模型组和滇黄精水提物组,每组8只。正常组以普通饲料喂养,其他组以高脂饲料喂养。建立模型同时滇黄精水... 目的检测代谢相关脂肪性肝病(MAFLD)肝线粒体中滇黄精药源成分的分布情况。方法24只6周龄雄性SD大鼠采用随机数字表法分为正常组、模型组和滇黄精水提物组,每组8只。正常组以普通饲料喂养,其他组以高脂饲料喂养。建立模型同时滇黄精水提物组按照8 g/(kg·d)灌胃滇黄精水提物,正常组与模型组灌胃等体积的生理盐水,连续14周。最后一次给药1 h后,取各组大鼠肝组织,分离得到线粒体,采用Semi-Pre-HPLC联合HPLC-MS二维色谱分析系统分析各组肝线粒体药源成分。结果MAFLD大鼠肝线粒体中检测到10种药源成分,其中7种已报道脂代谢调节活性,分别为薯蓣皂苷元、薯蓣皂苷、菝葜皂苷元、Pratioside D1、异甘草素、β-谷甾醇、常春藤皂苷元。结论检测到的10种药源成分可能是滇黄精调节线粒体缓解MAFLD的主要活性物质。 展开更多
关键词 semi-Pre-HPLC HPLC-MS 代谢相关脂肪性肝病 肝线粒体 滇黄精
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Hematization of Quartz Grains: Study of the Surface of Quartz Grains (M.E.B) and Semi-Quantitative Mineralization
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作者 Chia Marie Reine Kokoa Touvalé Marcel Kesse +2 位作者 Fory Yao Paul Assale Sougo Aoua Coulibaly Kouadio Affian 《Journal of Geoscience and Environment Protection》 2023年第11期82-90,共9页
Interest in the Côte d’Ivoire sedimentary basin has led to numerous investigations. All these investigations are aimed at understanding the functioning of the basin and a paleogeographic approach including sedim... Interest in the Côte d’Ivoire sedimentary basin has led to numerous investigations. All these investigations are aimed at understanding the functioning of the basin and a paleogeographic approach including sediment transport dynamics. However, the use of exoscopy and semi-quantitative mineralogy has been little developed. This study was carried out to compensate for this lack of interest in these methods. Its aim is to understand the transformation of quartz into hematite using exoscopy and semi-quantitative mineralogy in the Adiaké locality, in the eastern onshore basin of Côte d’Ivoire. Two methods were applied to 250 μm-diameter quartz grains from the 40 m coasts. Exoscopy provides information on microscopic texture, surface and corrosion, as well as determining the transport mechanism and deposition phases of quartz grains. Semi-quantitative mineralogy provides an estimate of the weight percentages of major element oxides and the ultrastructure of quartz grains. Exoscopy showed that these grains had been subjected to torrential fluvial transport. They were marked by mechanical and chemical traces during this transport and evolved in different environments. Semi-quantitative mineralogy shows the existence of negative and positive correlations between oxides. Negative correlations indicate a substitution, in order of importance, of silicon by iron, phosphorus and aluminum in these quartz. Positive correlations show that there is no substitution between the oxides concerned in these quartz grains. Divo’s quartz grains have recorded several mechanical and chemical microstructures of their sedimentary episodes, with the appearance of iron nodules in the ports left by silica. 展开更多
关键词 QUARTZ Exoscopy semi-Quantitative Mineralogy Adiaké Ivory Coast
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Cementless Semi-Constrained Rotating Platform Total Knee Replacement: A Concise Follow-Up of a Previous Report at a Minimum of Twenty Years
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作者 Frederick F. Buechel Sr. Frederick F. Buechel Jr. Thomas E. Helbig 《Open Journal of Orthopedics》 2023年第3期71-77,共8页
Background: A previous report evaluated the initial 310 cementless, Buechel-Pappas (B-P), Semi-Constrained Rotating Platform total knee replacements in 257 patients followed for an average of 7.6 years, range 2 - 18 y... Background: A previous report evaluated the initial 310 cementless, Buechel-Pappas (B-P), Semi-Constrained Rotating Platform total knee replacements in 257 patients followed for an average of 7.6 years, range 2 - 18 years. Diagnoses were osteoarthritis in 233 patients, post traumatic arthritis in 4 patients and rheumatoid arthritis in 22 patients. Knee Scores, using a strict knee scoring scale were 86.4% excellent, 12.3% good, 0.3% fair and 1.0% poor results. Survivorship, using an end point of revision for any mechanical reason (including component loosening, bearing wear and bearing dislocation) was 99.4%. Survivorship for a poor knee score (including persistent pain, loosening, instability and infection was 97.6%. The purpose of the present study is to report the updated results of this same patient cohort at a minimum follow-up of twenty years. Methods: The average age of patients at the time of surgery was 67 years, range 34 to 91 years. A total of 20 patients (22 knees) were still living, with a follow-up of 20 - 30 years (mean 23.47 years). The same strict knee scoring scale and survivorship analysis were used to evaluate patient outcomes at the 20 to 30 years interval. Results: Survivorship, in the current study, using the same end points as in the previous study, was 96.5% at the 20 and 30-year intervals. Late mechanical failure and osteolysis were not identified. Conclusion: This cementless, semi-constrained rotating platform total knee replacement has stood the test of time for more than 20 years and can be considered acceptable for long-term use, in properly selected patients. 展开更多
关键词 Knee Replacement CEMENTLESS semi-Constrained Rotating
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基于Semi-Markov模型沥青路面性能衰变规律研究
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作者 祁冰 宋书康 +1 位作者 丁博 靖立峥 《建筑技术开发》 2023年第1期123-125,共3页
为解决在路面使用性能预测过程中预测值与实测值间误差波动较大这一问题,采用Semi-Markov模型对山东省某国道的使用性能进行预测,同时将预测结果与实测数据进行对比。结果显示,Semi-Markov模型能够有效预测道路使用寿命,且对早期道路使... 为解决在路面使用性能预测过程中预测值与实测值间误差波动较大这一问题,采用Semi-Markov模型对山东省某国道的使用性能进行预测,同时将预测结果与实测数据进行对比。结果显示,Semi-Markov模型能够有效预测道路使用寿命,且对早期道路使用状况的预测结果精确度更高,而随着预测年限的延长,预测结果受道路养护措施的影响很大,需采取主动干预措施进行修正,Semi-Markov模型为准确预测沥青路面早期使用性能变化趋势并得到合理的养护决策提供可靠依据。 展开更多
关键词 道路工程 路用性能 预测模型 semi-Markov模型
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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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Effect of Pre-Swirling Flow on Performance and Flow Fields in Semi-Opened Axial Fan
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作者 Norimasa Shiomi Pin Liu Yoichi Kinoue 《Open Journal of Fluid Dynamics》 CAS 2023年第2期113-121,共9页
In this study, we tried to improve the performance by giving a pre-swirling flow to the radial inflow that occurred in the semi-opened axial fan. In addition, the flow fields of rotor outlet were clarified experimenta... In this study, we tried to improve the performance by giving a pre-swirling flow to the radial inflow that occurred in the semi-opened axial fan. In addition, the flow fields of rotor outlet were clarified experimentally, and the effect of pre-swirling flow was considered. The experiment was carried out using a performance test wind tunnel with a square cross section of 880 mm. Three types of casings were prepared, in which the blade tip protruded 0%, 20%, and 40% of the meridional chord length. They were called R25, R15, and R05, respectively, in the casing bellmouth model code. Guide blades for generating a pre-swirling flow were installed on the vertical wall surface of the casing. In addition, a vertical wall was installed 60% upstream of the meridional chord length as an obstacle to prevent axial inflow. The velocity fields of the rotor outlet were measured using a hot-wire anemometer. From the results, the pre-swirling flow did not significantly affect the fan performance. When there was no obstacles wall upstream, there was a partial increase in efficiency, but the difference was not so large. When there was an obstacle wall upstream, the efficiency increased overall in the case of R15, but in the case of R05, the efficiency increased only in the low flow rate region, and conversely decreased in the high flow rate region. By observing the blade outlet flow fields when the performance was improved, it was confirmed that the influence of the tip leakage vortex was weakened. 展开更多
关键词 Axial Fan semi-Opened Narrow Space Pre-Swirling Flow Fan Performance
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MULTI-VALUED TOTALLY QUASI-φ-ASYMPTOTICALLY NONEXPANSIVE SEMI-GROUPS AND STRONG CONVERGENCE THEOREMS IN BANACH SPACES
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作者 张石生 王林 赵云河 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期589-599,共11页
The purpose of this article is first to introduce the concept of multi-valued to- tally Quasi-φ-asymptotically nonexpansive semi-groups, which contains many kinds of semi- groups as its special cases, and then to mod... The purpose of this article is first to introduce the concept of multi-valued to- tally Quasi-φ-asymptotically nonexpansive semi-groups, which contains many kinds of semi- groups as its special cases, and then to modify the Halpern-Mann-type iteration algorithm for multi-valued totally Quasi-cS-asymptotically nonexpansive semi-groups to have the strong convergence under a limit condition only in the framework of Banach spaces. The results presented in this article improve and extend the corresponding results announced by many authors recently. 展开更多
关键词 Multi-valued totally Quasi-q^-asymptotically nonexpansive semi-groups mod-ified Halpern-Mann-type iteration multi-valued quasi-qS-symptotically nonex-pansive semi-groups multi-valued quasi-~b-nonexpansive semi-groups multi-valued relatively nonexpansive semi-groups generalized projection
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Simulation of Natural Convection Flow with Magneto-Hydrodynamics in a Wavy Top Enclosure with a Semi-Circular Heater
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作者 Mohammad Mahfuzul Islam Md. Abdul Alim +1 位作者 Md. Mahmud Alam Md. Jahirul Haque Munshi 《Open Journal of Applied Sciences》 CAS 2023年第4期591-603,共13页
Natural convection flow in enclosure has different applications such as room ventilation, heat exchangers, the cooling system of a building etc. The Finite-Element method based on the Galerkin weighted residual approa... Natural convection flow in enclosure has different applications such as room ventilation, heat exchangers, the cooling system of a building etc. The Finite-Element method based on the Galerkin weighted residual approach is used to solve two-dimensional governing mass, momentum and energy-equations for natural convection flow in the presence of a magnetic field on a roof top with semi-circular heater. In the enclosure the horizontal lower wall was heated, the vertical two walls were adiabatic, inside the semi-circular heater, the wavy top wall cooled. The parameters Rayleigh number, Hartmann number and Prandtl number are considered. The effects of the Hartmann number and Rayleigh number on the streamlines, isotherms, velocity profiles and average Nusselt number are examined graphically. The local Nusselt number and the average Nusselt number of the heated portion of the enclosure with the semi-circular heater are presented in this paper. Finally, for the validation of the existing work, the current results are compared with published results and the auspicious agreement is achieved. 展开更多
关键词 Natural Convection Magneto-Hydrodynamics (MHD) Finite Element Method (FEM) Wavy Enclosure semi-Circular Heater
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Sub-Differential Characterizations of Non-Smooth Lower Semi-Continuous Pseudo-Convex Functions on Real Banach Spaces
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作者 Akachukwu Offia Ugochukwu Osisiogu +4 位作者 Theresa Efor Friday Oyakhire Monday Ekhator Friday Nkume Sunday Aloke 《Open Journal of Optimization》 2023年第3期99-108,共10页
In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Su... In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Sub-differential. We extend the results on the characterizations of non-smooth convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the monotonicity of its sub-differentials to the lower semi-continuous pseudo-convex functions on real Banach spaces. 展开更多
关键词 Real Banach Spaces Pseudo-Convex Functions Pseudo-Monotone Maps Sub-Differentials Lower semi-Continuous Functions and Approximate Mean Value Inequality
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The Evolving Bipartite Network and Semi-Bipartite Network Models with Adjustable Scale and Hybrid Attachment Mechanisms
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作者 Peng Zuo Zhen Jia 《Open Journal of Applied Sciences》 2023年第10期1689-1703,共15页
The bipartite graph structure exists in the connections of many objects in the real world, and the evolving modeling is a good method to describe and understand the generation and evolution within various real complex... The bipartite graph structure exists in the connections of many objects in the real world, and the evolving modeling is a good method to describe and understand the generation and evolution within various real complex networks. Previous bipartite models were proposed to mostly explain the principle of attachments, and ignored the diverse growth speed of nodes of sets in different bipartite networks. In this paper, we propose an evolving bipartite network model with adjustable node scale and hybrid attachment mechanisms, which uses different probability parameters to control the scale of two disjoint sets of nodes and the preference strength of hybrid attachment respectively. The results show that the degree distribution of single set in the proposed model follows a shifted power-law distribution when parameter r and s are not equal to 0, or exponential distribution when r or s is equal to 0. Furthermore, we extend the previous model to a semi-bipartite network model, which embeds more user association information into the internal network, so that the model is capable of carrying and revealing more deep information of each user in the network. The simulation results of two models are in good agreement with the empirical data, which verifies that the models have a good performance on real networks from the perspective of degree distribution. We believe these two models are valuable for an explanation of the origin and growth of bipartite systems that truly exist. 展开更多
关键词 Bipartite Networks Evolving Model semi-Bipartite Networks Hybrid Attachment Degree Distribution
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