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η-函数与Mutation 被引量:1
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作者 陶志雄 《浙江大学学报(理学版)》 CAS CSCD 2001年第1期19-23,共5页
基于文 [2 ]等的工作 ,本文对文 [5]构造的不变量η-函数在 mutation下进行了讨论 .研究表明当mutation仅在链环的一个分支上作和某种情形下在两个分支交叉处作 ,η-函数具有不变性 .此外 ,还得到了链环的第一分支从伴随纽结改变为卫星... 基于文 [2 ]等的工作 ,本文对文 [5]构造的不变量η-函数在 mutation下进行了讨论 .研究表明当mutation仅在链环的一个分支上作和某种情形下在两个分支交叉处作 ,η-函数具有不变性 .此外 ,还得到了链环的第一分支从伴随纽结改变为卫星纽结的 η-函数公式 . 展开更多
关键词 η-函数 mutation 伴随纽结 卫星纽结 平凡纽结 分支 首选尾线
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17α-hydroxylase/17,20 carbon chain lyase deficiency caused by p.Tyr329fs homozygous mutation:Three case reports 被引量:1
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作者 Dai Zhang Jian-Ran Sun +4 位作者 Jiang Xu Yan Xing Mao Zheng Shan-Dong Ye Jie Zhu 《World Journal of Clinical Cases》 SCIE 2021年第8期1923-1930,共8页
p.Tyr329fs is a cytochrome P450c17 mutation among Chinese individuals.However,data on 17-α-hydroxylase deficiency caused by cytochrome P450c17 p.Tyr329fs homozygous mutation are lacking.This paper is a case report of... p.Tyr329fs is a cytochrome P450c17 mutation among Chinese individuals.However,data on 17-α-hydroxylase deficiency caused by cytochrome P450c17 p.Tyr329fs homozygous mutation are lacking.This paper is a case report of three patients homozygous for p.Tyr329fs who were diagnosed with 17-α-hydroxylase deficiency between 2005 and 2019.CASE SUMMARY Case 1 presented with hypertension,hypokalemia,sexual infantilism and delayed bone age.The patient had a 46,XY karyotype,was homozygous for p.Tyr329fs and was recently treated with dexamethasone 0.375 mg qn.Case 2 presented with hypokalemia,sexual infantilism,osteoporosis and delayed bone age.The patient had a 46,XY karyotype,was homozygous for p.Tyr329fs and was treated with dexamethasone 0.75 mg qn at the last follow-up.Serum potassium and blood pressure could be maintained within normal range for cases 1 and 2.Case 3 presented with amenorrhea,sexual infantilism,osteopenia and delayed bone age.The patient had a 46,XX karyotype,was homozygous for p.Tyr329fs and was treated with dexamethasone 0.75 mg qn and progynova 1 mg qd.Outpatient follow-up revealed an adrenocorticotropic hormone(8 AM)of<5.00 pg/mL.CONCLUSION The homozygous p.Tyr329fs mutation usually manifests as a combined deficiency,and definitive diagnosis depends primarily on genetic testing. 展开更多
关键词 Cytochrome P450c17 17-α-hydroxylase-17 20-lyase deficiency Phenotype mutation Case report
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Screening of NKX2-5,GATA4,ZIC3 gene mutations in sporadic congenital simple heart disease in Hainan Province
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作者 LI Qing-Man GUO Feng +7 位作者 LING Yi LI Hui-hui LIU Fang-fang LIU Hui WEN Zhuang-fei SUN Wei-wei LIU Yi-heng ZHANG Hai-ying 《Journal of Hainan Medical University》 2022年第19期32-36,共5页
Objective:Congenital heart disease(CHD)is caused by abnormal cardiac development,which is the most common congenital malformation at home and abroad.NKX2-5,GATA4 and ZIC3 have been shown to be associated with CHD.This... Objective:Congenital heart disease(CHD)is caused by abnormal cardiac development,which is the most common congenital malformation at home and abroad.NKX2-5,GATA4 and ZIC3 have been shown to be associated with CHD.This experiment explored the relationship between NKX2-5,GATA4 and ZIC3 gene mutations and sporadic CHD in Hainan Province.Methods:To collect 210 sporadic CHD patients in Hainan,the DNA of patients was extracted from blood,and the target gene fragments were amplified.Using high-resolution melting(HRM)and DNA sequencing technology,and we analyzed the sequences of NKX2-5,GATA4 and ZIC3 genes.Results:NKX2-5,GATA4 and ZIC3 genes were sequenced in 210 CHD patients,and seven gene mutations were found,including NKX2-5 heterozygous missense mutation(c.178G>T)and three heterozygous mutations in GATA4(c.677C>T,c.928A>G,c.1123G>A),three heterozygous mutations in ZIC3(c.19G>C,c.1255C>G,c.1348C>T),in which NKX2-5(c.178G>T),GATA4(c.1123G>A),and ZIC3(c.1255C>G,c.1348C>T)are new mutation sites.These gene mutations were predicted to be pathogenic mutations by bioinformatics software.Conclusion:Conclusion:Seven gene mutations were found in 210 patients,and it was the first report that the gene mutations of NKX2-5,GATA4 and ZIC3 in Hainan Province associated with the pathogenesis of CHD. 展开更多
关键词 Congenital heart disease Gene mutation NKX2-5 GATA4 ZIC3
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基于NSGA-III算法求解柔性作业车间调度问题
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作者 宋存利 朱建伟 李金泰 《机电工程技术》 2024年第5期11-15,85,共6页
针对多目标柔性作业车间调度问题,提出一种改进NSGA-Ⅲ算法,以完工时间、机器总负荷、瓶颈机器负荷为目标建立调度模型。首先,为提高种群的多样性,提出一种基于惩罚的边界相交距离定义关联操作中种群个体与参考向量之间的距离;其次,为... 针对多目标柔性作业车间调度问题,提出一种改进NSGA-Ⅲ算法,以完工时间、机器总负荷、瓶颈机器负荷为目标建立调度模型。首先,为提高种群的多样性,提出一种基于惩罚的边界相交距离定义关联操作中种群个体与参考向量之间的距离;其次,为提高环境选择的计算效率,利用基于惩罚的边界相交距离消除机制来保护个体,降低了个体保护策略的计算成本;最后,为避免种群陷入局部最优,在遗传算子中采用一种改进的变异策略。运用两个评价指标与NSGA-Ⅲ算法进行比较,其收敛性与多样性均由于NSGA-Ⅲ算法。同时在4个Kacem算例上进行测试得出改进NSGA-Ⅲ算法解的质量较高,最后通过实际的生产实例证明改进的NSGA-Ⅲ算法优于或等同于现存在的方法,也证明了该方法在解决多目标柔性作业车间调度难题上的可操作性。 展开更多
关键词 多目标柔性作业车间 NSGA- 变异策略 消除机制
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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:42
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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Improved particle swarm optimization algorithm for fuzzy multi-class SVM 被引量:17
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作者 Ying Li Bendu Bai Yanning Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期509-513,共5页
An improved particle swarm optimization(PSO) algorithm is proposed to train the fuzzy support vector machine(FSVM) for pattern multi-classification.In the improved algorithm,the particles studies not only from its... An improved particle swarm optimization(PSO) algorithm is proposed to train the fuzzy support vector machine(FSVM) for pattern multi-classification.In the improved algorithm,the particles studies not only from itself and the best one but also from the mean value of some other particles.In addition,adaptive mutation was introduced to reduce the rate of premature convergence.The experimental results on the synthetic aperture radar(SAR) target recognition of moving and stationary target acquisition and recognition(MSTAR) dataset and character recognition of MNIST database show that the improved algorithm is feasible and effective for fuzzy multi-class SVM training. 展开更多
关键词 particle swarm optimization(PSO) fuzzy support vector machine(FSVM) adaptive mutation multi-classification.
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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block 被引量:2
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作者 朱参战 崔长琮 +5 位作者 张全发 薛小临 刘维维 刘引会 《South China Journal of Cardiology》 CAS 2001年第2期101-105,共5页
Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS ... Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function. 展开更多
关键词 multi - site cardiac pacingHemodynamics
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Research on A Master - slave Multi - microcomputers Control System for Hollow Spindle Fancy Yarn Spinning Machine
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作者 李志蜂 陈子展 阵瑞琪 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期49-52,共4页
In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardwar... In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology. 展开更多
关键词 hollow SPINDLE FANCY YAM spinning machine mechatrvnical fusion MASTER - SLAVE multi - microcomputers control system PC - BUS.
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On the Representation of Multi-layer Woven Structure
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作者 易洪雷 丁辛 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期14-16,共3页
A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the rein... A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed. 展开更多
关键词 multi - layer woven FABRIC structural parame-ter BINDING PATTERN TEXTILE composite .
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Molecular characterization of antimicrobial multi-drug resistance in non-typhoidal Salmonellae from chicken and clam in Mangalore, India 被引量:2
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作者 Yemisi Olukemi Adesiji Santhosh Kogaluru Shivakumaraswamy +2 位作者 Vijaya Kumar Deekshit Girisha Shivani Kallappa Indrani Karunasagar 《The Journal of Biomedical Research》 CAS CSCD 2018年第3期237-244,共8页
Salmonella enterica has been documented as one of the leading causes of salmonellosis throughout the world and is most commonly associated with the consumption of contaminated food products. Thus, this research was ai... Salmonella enterica has been documented as one of the leading causes of salmonellosis throughout the world and is most commonly associated with the consumption of contaminated food products. Thus, this research was aimed at studying the antimicrobial susceptibility pattern and detection of quinolone resistance in Salmonella spp isolated from food of animal origin. Thirty-six Salmonella isolates comprising 8 from poultry and 28 from seafood(clams) were identified, serotyped and characterized for their antimicrobial susceptibility against 10 different antibiotics. Plasmid DNA was isolated from all the isolates by alkaline lysis, quinolone resistant non-typhoidal S. Weltevreden were examined for mutation in the DNA gyrase coding gene. Among the 36 Salmonella isolates, 20 were S. weltevreden(8 from poultry and 12 from seafood) and 16 were S. Typhimurium(from seafood). All the isolates showed multiple resistance to nalidixic acid, tetracycline, co-trimoxazole and nitrofurantoin, but, interestingly, the isolates were 100% susceptible to ampicillin, chloramphenicol and gentamicin. Resistant isolates from the study carried the genes responsible for resistance to respective antibiotics. The strain S130 isolated in the study showed single point mutation,Asp87Gly, at position 87 in quinolone resistance determining region. It revealed mutation in quinolone resistance determining region as a cause for quinolone resistance in non-typhoidal Salmonellae. The occurrence of genes accountable for plasmid mediated resistance to quinolones(viz., qnrA, qnrB and qnrS) in plasmid of non-typhoidal Salmonellae isolates provides evidence for plasmid mediated quinolone resistance. 展开更多
关键词 mutation multi-drug resistant non-typhoidal Salmonellae plasmid mediated quinolone resistance quinolone resistance determining region
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Computer-aided Pattern Design of Multi-bar Warp Knitted Fabrics
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作者 李炜 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期85-87,共3页
To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the ... To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the computer-aided pattern design of multi-barwarp knitted fabrics.In terms of the special propertiesof the computer-aided pattern design of multi-barwarp knitted fabrics,the Object Oriented Program(OOP)programming-Object Windows class Library(OWL)programming is selected.According to thecharacters of the OWL programming,various functionsare defined.Pattern design and technical parameters canbe output,which offers a great convenience for the fac-tory. 展开更多
关键词 multi - bar WARP KNITTED fabric computer -aided PATTERN design PATTERN Object Windows class Library (OWL) programming.
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MODS: A Novel Metaheuristic of Deterministic Swapping for the Multi-Objective Optimization of Combinatorials Problems
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作者 Elias David Nifio Ruiz Carlos Julio Ardila Hemandez +2 位作者 Daladier Jabba Molinares Agustin Barrios Sarmiento Yezid Donoso Meisel 《Computer Technology and Application》 2011年第4期280-292,共13页
This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Auto... This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Automata (MDFA) is defined. MDFA allows the representation of the feasible solutions space of combinatorial problems. Second, it is defined and implemented a metaheuritic based on MDFA theory. It is named Metaheuristic of Deterministic Swapping (MODS). MODS is a local search strategy that works using a MDFA. Due to this, MODS never take into account unfeasible solutions. Hence, it is not necessary to verify the problem constraints for a new solution found. Lastly, MODS is tested using well know instances of the Bi-Objective Traveling Salesman Problem (TSP) from TSPLIB. Its results were compared with eight Ant Colony inspired algorithms and two Genetic algorithms taken from the specialized literature. The comparison was made using metrics such as Spacing, Generational Distance, Inverse Generational Distance and No-Dominated Generation Vectors. In every case, the MODS results on the metrics were always better and in some of those cases, the superiority was 100%. 展开更多
关键词 METAHEURISTIC deterministic finite automata combinatorial problem multi - objective optimization metrics.
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Study on MCM Interconnect Test Generation Based on Ant Algorithm with Mutation Operator
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作者 陈雷 《上海交通大学学报》 EI CAS CSCD 北大核心 2007年第S2期150-153,共4页
A novel multi-chip module(MCM) interconnect test generation scheme based on ant algorithm(AA) with mutation operator was presented.By combing the characteristics of MCM interconnect test generation,the pheromone updat... A novel multi-chip module(MCM) interconnect test generation scheme based on ant algorithm(AA) with mutation operator was presented.By combing the characteristics of MCM interconnect test generation,the pheromone updating rule and state transition rule of AA is designed.Using mutation operator,this scheme overcomes ordinary AA’s defects of slow convergence speed,easy to get stagnate,and low ability of full search.The international standard MCM benchmark circuit provided by the MCNC group was used to verify the approach.The results of simulation experiments,which compare to the results of standard ant algorithm,genetic algorithm(GA) and other deterministic interconnecting algorithms,show that the proposed scheme can achieve high fault coverage,compact test set and short CPU time,that it is a newer optimized method deserving research. 展开更多
关键词 multi-CHIP module(MCM) INTERCONNECT TEST ANT algorithm(AA) TEST generation mutation
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多尺度变异粒子群优化MK-LSSVM的轴承寿命预测 被引量:17
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作者 张焱 汤宝平 熊鹏 《仪器仪表学报》 EI CAS CSCD 北大核心 2016年第11期2489-2496,共8页
提出一种基于多尺度变异粒子群优化(MSPSO)算法和多核最小二乘支持向量机(MK-LSSVM)的预测新方法用于滚动轴承寿命预测。提取小波包相对能量特征对轴承性能衰退予以描述,提出MSPSO算法对MK-LSSVM模型参数进行优化选取,构造融合多核函数... 提出一种基于多尺度变异粒子群优化(MSPSO)算法和多核最小二乘支持向量机(MK-LSSVM)的预测新方法用于滚动轴承寿命预测。提取小波包相对能量特征对轴承性能衰退予以描述,提出MSPSO算法对MK-LSSVM模型参数进行优化选取,构造融合多核函数的LSSVM模型实现轴承寿命估计。MK-LSSVM中多核函数的引入克服了单核LSSVM对核函数类型强依赖性的弱点,MSPSO算法中种群全局大尺度均匀变异与个体局部邻域小尺度变异搜索联合策略的提出在增强种群多样性的同时保证了粒子群局部精确搜索的能力。利用实测滚动轴承振动数据分析,验证了所提MSPSO算法在模型参数优化及优化MKLSSVM模型在滚动轴承寿命预测应用中的有效性。 展开更多
关键词 寿命预测 多尺度变异粒子群优化 多核最小二乘支持向量机
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一种快速获得基因密码子偏爱性改造的方法——SOE-PCR 被引量:6
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作者 王艳君 杨谦 《中国生物工程杂志》 CAS CSCD 北大核心 2008年第8期96-99,共4页
SOE-PCR采用具有互补末端的引物,使PCR产物形成重叠链,在不需要内切酶消化和连接酶处理的条件下实现DNA片段的拼接,能够高效、快速地实现基因的定点突变。应用SOE-PCR原理成功地实现了对几丁质酶基因chi58的5个位点的突变,构建了几丁质... SOE-PCR采用具有互补末端的引物,使PCR产物形成重叠链,在不需要内切酶消化和连接酶处理的条件下实现DNA片段的拼接,能够高效、快速地实现基因的定点突变。应用SOE-PCR原理成功地实现了对几丁质酶基因chi58的5个位点的突变,构建了几丁质酶基因密码子偏爱性改造突变体—chi58A。实验证明,SOE-PCR具有简捷、快速、高效的优点。扩增过程中未引入其他突变,获得的chi58A突变体基因片段可以用于后续的分子克隆。 展开更多
关键词 SOE—PCR 多点突变 密码子偏爱性改造
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γ-多聚谷氨酸产生菌高效诱变育种的研究 被引量:7
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作者 陈咏竹 田天丽 +5 位作者 卢锦 陈智 王嫱 高婷 张兴宇 孙启玲 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第2期389-394,共6页
设计了几组不同的诱变条件对γ多聚谷氨酸生产菌BacilluslicheniformisATCC9945A进行诱变,诱变后将所有菌株混合,以此未经筛选的混合菌共同发酵,并以终产量为指标对发酵条件进行连续的定向调控,使发酵条件逐渐向高产正突变株倾斜,产量... 设计了几组不同的诱变条件对γ多聚谷氨酸生产菌BacilluslicheniformisATCC9945A进行诱变,诱变后将所有菌株混合,以此未经筛选的混合菌共同发酵,并以终产量为指标对发酵条件进行连续的定向调控,使发酵条件逐渐向高产正突变株倾斜,产量得以逐步提高.同时在混合菌状态下找到适合高产正突变株的发酵条件,以此发酵条件作为筛选平板,对混合菌分离纯化,选育到γPGA高产菌Zγ29,产量是出发菌株的4.14倍,筛选条件即为该突变株的最佳发酵条件. 展开更多
关键词 复合诱变 多组混合 复杂系统定向调控技术 高效诱变育种 γ-多聚谷氨酸
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一类Job-shop多目标优化调度方法 被引量:2
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作者 曾强 杨育 +1 位作者 王小磊 梁学栋 《计算机工程与应用》 CSCD 北大核心 2010年第23期215-218,共4页
提出了一类Job-shop多目标优化调度方法。构建了一个以工件平均流程时间最短、全部工件完工时间最短的Job-shop优化调度模型,并针对模型提出了一种分阶段混合变异的禁忌搜索算法。为增强算法收敛性,利用"逆序变异"和"基... 提出了一类Job-shop多目标优化调度方法。构建了一个以工件平均流程时间最短、全部工件完工时间最短的Job-shop优化调度模型,并针对模型提出了一种分阶段混合变异的禁忌搜索算法。为增强算法收敛性,利用"逆序变异"和"基因段交换变异"找到了较好的初解,在此基础上利用"基因交换变异"继续搜索近优解。以10个算例验证了提出的Job-shop多目标优化调度方法的正确性和有效性。 展开更多
关键词 JOB-SHOP调度 禁忌搜索算法 分阶段混合变异
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基于粒子群优化算法的电网GIC-Q多目标优化策略 被引量:21
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作者 杨培宏 刘连光 +2 位作者 刘春明 冯士伟 郑许朋 《电力自动化设备》 EI CSCD 北大核心 2017年第3期93-99,共7页
地磁感应电流(GIC)流经变压器绕组会产生直流偏磁现象,造成变压器无功损耗增加,破坏电网无功平衡,影响电网安全稳定运行。为了有效地抑制GIC对电网的不良影响,以无功补偿设备成本和电压偏移量最小为目标,提出一种基于粒子群优化算法的... 地磁感应电流(GIC)流经变压器绕组会产生直流偏磁现象,造成变压器无功损耗增加,破坏电网无功平衡,影响电网安全稳定运行。为了有效地抑制GIC对电网的不良影响,以无功补偿设备成本和电压偏移量最小为目标,提出一种基于粒子群优化算法的多目标无功优化策略,保证地磁场扰动下电网无功平衡。所提策略利用小生境共享机制不断更新粒子位置,并依据拥挤距离排序对Pareto最优解进行存档,保持解的多样性和均匀性;引入混沌变异避免陷入局部最优解,同时提高全局搜索能力。GIC标准算例的仿真结果验证了所提策略的准确性和有效性。 展开更多
关键词 地磁场扰动 地磁感应电流 无功优化 电压偏移 多目标优化 小生境 粒子群优化算法 混沌变异 PARETO最优
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基于混合多值离散粒子群优化的混合极性Reed-Muller最小化算法 被引量:11
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作者 卜登立 江建慧 《电子与信息学报》 EI CSCD 北大核心 2013年第2期361-367,共7页
针对布尔函数系统的混合极性Reed-Muller(Mixed-Polarity Reed-Muller,MPRM)最小化问题,该文提出了一种混合多值离散粒子群优化算法。为解决多样性损失,改善优化结果,兼顾算法的效率和精度,算法采用多群协同优化方法,并提出了概率变异... 针对布尔函数系统的混合极性Reed-Muller(Mixed-Polarity Reed-Muller,MPRM)最小化问题,该文提出了一种混合多值离散粒子群优化算法。为解决多样性损失,改善优化结果,兼顾算法的效率和精度,算法采用多群协同优化方法,并提出了概率变异更新、没有重复的更新以及群间重复最优变异3种更新和变异策略。实验结果表明,和模拟退火遗传算法相比,所构造算法能够在获得基本相同优化结果的同时,提高MPRM最小化的时间效率。 展开更多
关键词 数字电路 布尔函数系统 混合极性Reed—Muller 多值离散粒子群优化 多群 更新和变异策略
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