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健脾2号口服液对小鼠肠道菌群影响的实验研究
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作者 李钰婷 李茹月 李威 《按摩与康复医学》 2019年第8期48-50,53共4页
目的:评价健脾2号口服液(JP)对小鼠正常肠道菌群的调节作用。方法:将50只雌性BALB/c小鼠随机分为对照组、低聚半乳糖组(OG, 0.50mg/kg)和健脾2号口服液高(JP-H, 6.00mg/kg)、中(JP-M, 3.00mg/kg)、低(JP-L, 1.50mg/kg)剂量组,给药前各... 目的:评价健脾2号口服液(JP)对小鼠正常肠道菌群的调节作用。方法:将50只雌性BALB/c小鼠随机分为对照组、低聚半乳糖组(OG, 0.50mg/kg)和健脾2号口服液高(JP-H, 6.00mg/kg)、中(JP-M, 3.00mg/kg)、低(JP-L, 1.50mg/kg)剂量组,给药前各组均无菌采取小鼠直肠粪便0.1g,再每组灌胃相应药物(1次/d),空白组给予蒸馏水,连续14d。末次给药后24h,同法取粪便,将两次所取粪便培养后,以生化反应、革兰氏染色镜检、菌落形态等鉴定及计录菌落数,并算出每克湿便中所含肠道双歧杆菌、乳杆菌、肠球菌、肠杆菌、产气荚膜梭菌的菌落数,取对数后进行统计。结果:给药前至给药后14d,各组小鼠体重增加趋势基本相同,各个时间点体重无显著性差异(P>0.05);灌胃14d,与对照组比较,给药后OG组、JP三剂量组乳杆菌和双歧杆菌数量有显著性增加(P<0.01);JP三剂量组肠球菌和肠杆菌数量均有显著性减少(P<0.01);而OG、JP三剂量组产气荚膜梭菌数量均有显著性减少(P<0.01)。结论:健脾2号口服液具有明显的调节肠道菌群作用,可用于脾气亏虚、消化不良的治疗。 展开更多
关键词 肠道菌群 健脾2号口服液 小鼠 菌落数 双歧杆菌 乳杆菌 肠球菌 肠杆菌 产气荚膜梭菌
An improved artificial bee colony algorithm with MaxTF heuristic rule for two-sided assembly line balancing problem
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作者 Xiaokun DUAN Bo WU +2 位作者 Youmin HU Jie LIU Jing XIONG 《机械工程前沿:英文版》 CSCD 2019年第2期241-253,共13页
Two-sided assembly line is usually used for the assembly of large products such as cars,buses,and trucks.With the development of technical progress,the assembly line needs to be reconfigured and the cycle time of the ... Two-sided assembly line is usually used for the assembly of large products such as cars,buses,and trucks.With the development of technical progress,the assembly line needs to be reconfigured and the cycle time of the line should be optimized to satisfy the new assembly process.Two-sided assembly line balancing with the objective of minimizing the cycle time is called TALBP-2.This paper proposes an improved artificial bee colony(IABC)algorithm with the MaxTF heuristic rule.In the heuristic initialization process,the MaxTF rule defines a new task's priority weight.On the basis of priority weight,the assignment of tasks is reasonable and the quality of an initial solution is high.In the IABC algorithm,two neighborhood strategies are embedded to balance the exploitation and exploration abilities of the algorithm.The employed bees and onlooker bees produce neighboring solutions in different promising regions to accelerate the convergence rate.Furthermore,a well-designed random strategy of scout bees is developed to escape local optima.The experimental results demonstrate that the proposed MaxTF rule performs better than other heuristic rules,as it can find the best solution for all the 10 test cases.A comparison of the IABC algorithm and other algorithms proves the effectiveness of the proposed IABC algorithm.The results also denote that the IABC algorithm is efficient and stable in minimizing the cycle time for the TALBP-2,and it can find 20 new best solutions among 25 large-sized problem cases. 展开更多
关键词 two-sided assembly line balancing PROBLEM artificial BEE COLONY algorithm HEURISTIC RULES time BOUNDARY
Optimization of broadband omnidirectional antireflection coatings for solar cells 预览
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作者 Xia Guo Qiaoli Liu +5 位作者 Huijun Tian Ben Li Hongyi Zhou Chong Li Anqi Hu Xiaoying He 《半导体学报:英文版》 EI CAS CSCD 2019年第3期33-38,共6页
Broadband and omnidirectional antireflection coating is generally an effective way to improve solar cell efficiency, because the destructive interference between the reflected and incident light can maximize the light... Broadband and omnidirectional antireflection coating is generally an effective way to improve solar cell efficiency, because the destructive interference between the reflected and incident light can maximize the light transmission into the absorption layer. In this paper, we report the incident quantum efficiency ηin, not incident energy or power, as the evaluation function by the ant colony algorithm optimization method, which is a swarm-based optimization method. Also, SPCTRL2 is proposed to be incorporated for accurate optimization because the solar irradiance on a receiver plane is dependent on position, season, and time. Cities of Quito, Beijing and Moscow are selected for two-and three-layer antireflective coating optimization over λ = [300,1100] nm and θ = (0°, 90°)The ηin increases by 0.26%, 1.37% and 4.24% for the above 3 cities, respectively, compared with that calculated by other rigorous optimization algorithms methods, which is further verified by the effect of position and time dependent solar spectrum on the antireflective coating design. 展开更多
关键词 ANTIREFLECTION coating ANT COLONY algorithm INCIDENT quantum efficiency SPCTRL2
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茯砖茶中金花菌菌落计数方法的优化 预览
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作者 刘凯利 黄亚亚 +3 位作者 万斌 梁艳 胡歆 纪晓明 《食品研究与开发》 CAS 北大核心 2019年第3期190-194,共5页
金花菌数量是审评茯砖茶产品质量好坏的关键指标。以国标为依据,采用单因素试验和响应面分析法优化茯砖茶中金花菌菌落总数计数方法。结果表明,样品前处理的最佳条件为:筛子目数80目,无菌稀释液为0.85%NaCl溶液,振摇时间50 min。该条件... 金花菌数量是审评茯砖茶产品质量好坏的关键指标。以国标为依据,采用单因素试验和响应面分析法优化茯砖茶中金花菌菌落总数计数方法。结果表明,样品前处理的最佳条件为:筛子目数80目,无菌稀释液为0.85%NaCl溶液,振摇时间50 min。该条件下,金花菌菌落总数为(50.75±1.1)×105CFU/g。优化方法得到的金花菌菌落总数是国标方法的5倍左右。 展开更多
关键词 茯砖茶 金花菌 冠突散囊菌 菌落 计数方法 优化
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殖民语境下女性文化身份建构与文学表达--以伪满洲国女作家但娣的创作为中心 预览
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作者 王越 《青岛农业大学学报:社会科学版》 2019年第2期85-89,共5页
从1931年"九一八"事变到1945年8月17日溥仪退位,日本殖民者对中国东北地区进行了长达十四年的殖民统治。由于殖民文化情境是通过干预作家来干预文学的,因此作为中介的作家,其文学姿态和文学选择就成为研究伪满洲国文学的重要... 从1931年"九一八"事变到1945年8月17日溥仪退位,日本殖民者对中国东北地区进行了长达十四年的殖民统治。由于殖民文化情境是通过干预作家来干预文学的,因此作为中介的作家,其文学姿态和文学选择就成为研究伪满洲国文学的重要切入点。伪满时期著名女作家但娣具有受殖者、留日学生、新文学作家等多重文化身份,她的作品呈现出殖民地女性知识分子独特的生命体验和文学姿态。但娣将民族知识分子和女性书写者两种文化身份结合起来,她的小说真实地表现出被殖民者在异态时空中的生命状态与心理状态。 展开更多
关键词 但娣 伪满洲国 殖民地 文化身份 文学姿态
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Intragroup social dynamics vary with the presence of neighbors in a cooperatively breeding fish
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作者 Jennifer K. Hellmann Ian M. Hamilton 《动物学报:英文版》 SCIE CAS CSCD 2019年第1期21-31,共11页
Conflict is an in here nt part of social life in group-living species. Group members may mediate conflict through submissive and affiliative behaviors, which can reduce aggression, stabilize dominance hierarchies, and... Conflict is an in here nt part of social life in group-living species. Group members may mediate conflict through submissive and affiliative behaviors, which can reduce aggression, stabilize dominance hierarchies, and foster group cohesion. The frequency and resolution of within-group conflict may vary with the presenee of neighboring groups. Neighbors can threaten the territory or resources of the whole group, promoting behaviors that foster within-group cohesion. However, neighbors may also foster conflict of interests among group members: opportunities for subordinate dispersal may alter conflict among dominants and subordinates while opportunities for extrapair reproduction may increase conflict between mates. To understand how neighbors mediate within-group conflict in the cooperatively breeding fish Neolamprologus pulcher, we measured behavioral dynamics and social network structure in isolated groups, groups recently exposed to neighbors, and groups with established neighbors. Aggression and submission between the dominant male and female pair were high in isolated groups, but dominant aggression was directly primarily at subordinates when groups had neighbors. This suggests that neighbors attenuate conflict between mates and foster conflict between dominants and subordinates. Further, aggression and submission between similarly sized group members were most frequent when groups had neighbors, suggesting that neighbors induce rank-related conflict. We found relatively little change in within-group affiliative networks across treatments, suggesting that the presence of neighbors does not alter behaviors associated with promoting group cohesion. Collectively, these results provide some of the first empirical insights into the extent to which intragroup behavioral networks are mediated by intergroup interactions and the broader social context. 展开更多
关键词 affiliation COLONY CONFLICT EXPONENTIAL random GRAPH model Neolamprologus pulcher network
Design optimization of multilayer perceptron neural network by ant colony optimization applied to engine emissions data
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作者 MARTINEZ-MORALES Jose QUEJ-COSGAYA Hector +2 位作者 LAGUNAS-JIMENEZ Jose PALACIOS-HERNANDEZ Elvia MORALES-SALDANA Jorge 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第6期1055-1064,共10页
A multilayer perceptron(MLP) artificial neural network(ANN) model has been optimized by the multi-objective ant colony optimization(MOACO) algorithm, which uses three objective functions. A sensitivity analysis to cho... A multilayer perceptron(MLP) artificial neural network(ANN) model has been optimized by the multi-objective ant colony optimization(MOACO) algorithm, which uses three objective functions. A sensitivity analysis to choose MOACO parameter values is carried out by calculating hypervolume metric, and the proposed approach adopts the Vlsekriterijumska Optimizacija I Kompromisno Resenje(VIKOR) decision method to choose final compromised solution on the Pareto front obtained from MOACO. As a result, we used the MLP-MOACO developed model to estimate the value of engine emissions of NOxin a four stroke, spark ignition(SI) gasoline engine and observed acceptable correlation coefficient(R^2) of 0.99978. 展开更多
关键词 ANT COLONY optimization MULTILAYER PERCEPTRON artificial NEURAL networks hypervolume engine EMISSIONS
北美殖民地移民的农业探讨 预览
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作者 张兰星 《农业考古》 2019年第3期216-224,共9页
哥伦布发现新大陆后,欧洲移民陆续涌入北美,他们吸取印第安人的农耕经验,发展出具有区域特色的殖民地农业。移民还引入传统的旧大陆农具,提高了劳作效率。北美殖民地农业的一大特点是地多人少,相关管理较为混乱,造成不少问题,对农业发... 哥伦布发现新大陆后,欧洲移民陆续涌入北美,他们吸取印第安人的农耕经验,发展出具有区域特色的殖民地农业。移民还引入传统的旧大陆农具,提高了劳作效率。北美殖民地农业的一大特点是地多人少,相关管理较为混乱,造成不少问题,对农业发展产生一定负面影响。 展开更多
关键词 北美 殖民地 移民 农业
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微囊藻与水体细菌相互关系的研究进展 预览
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作者 张佳 张蔚珍 +2 位作者 王欢 陈隽 沈宏 《水生生物学报》 CAS CSCD 北大核心 2019年第2期448-456,共9页
近年来,微生物群落在水生态系统中的结构和功能受到了越来越多的关注。在富营养化水体中细菌在微囊藻水华的发生、发展及衰亡、降解过程中发挥着重要的作用。文章总结了水体中微囊藻与细菌独有的群落结构特征,以及微囊藻与细菌群落对环... 近年来,微生物群落在水生态系统中的结构和功能受到了越来越多的关注。在富营养化水体中细菌在微囊藻水华的发生、发展及衰亡、降解过程中发挥着重要的作用。文章总结了水体中微囊藻与细菌独有的群落结构特征,以及微囊藻与细菌群落对环境因素变化的响应等方面的研究成果。在微囊藻与细菌的相互作用方面,从藻细胞微环境中附着细菌对微囊藻生长的促进或抑制作用,细菌在微囊藻群体的形成和维持过程的作用,细菌参与的微囊藻水华的聚集和降解过程,细菌对微囊藻毒素的降解作用等方面进行了综述。文章还对未来微囊藻与细菌相互关系的研究热点以及可利用的组学技术等进行了展望。 展开更多
关键词 微囊藻 细菌 相互作用 群落 群体 微生物
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Research on a Task Planning Method for Multi-Ship Cooperative Driving
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作者 陈姚节 项珊珊 陈飞翔 《上海交通大学学报:英文版》 EI 2019年第2期233-242,共10页
A new method for a cooperative multi-task allocation problem(CMTAP) is proposed in this paper,taking into account the multi-ship, multi-target, multi-task and multi-constraint characteristics in a multi-ship cooperati... A new method for a cooperative multi-task allocation problem(CMTAP) is proposed in this paper,taking into account the multi-ship, multi-target, multi-task and multi-constraint characteristics in a multi-ship cooperative driving(MCD) system. On the basis of the general CMTAP model, an MCD task assignment model is established. Furthermore, a genetic ant colony hybrid algorithm(GACHA) is proposed for this model using constraints, including timing constraints, multi-ship collaboration constraints and ship capacity constraints. This algorithm uses a genetic algorithm(GA) based on a task sequence, while the crossover and mutation operators are based on similar tasks. In order to reduce the dependence of the GA on the initial population, an ant colony algorithm(ACA) is used to produce the initial population. In order to meet the environmental constraints of ship navigation, the results of the task allocation and path planning are combined to generate an MCD task planning scheme. The results of a simulated experiment using simulated data show that the proposed method can make the assignment more optimized on the basis of satisfying the task assignment constraints and the ship navigation environment constraints. Moreover, the experimental results using real data also indicate that the proposed method can find the optimal solution rapidly, and thus improve the task allocation efficiency. 展开更多
关键词 multi-ship cooperative task ALLOCATION path planning MULTI-TASK MULTI-OBJECTIVE genetic ant COLONY hybrid algorithm(GACHA)
Retrieval of aerosol optical constants from angular light-scattering measurement signals using principal component analysis approach
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作者 Zhenzong He Junkui Mao +1 位作者 Xingsi Han Hao Wang 《中国颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第2期210-218,共9页
An angular light-scattering measurement (ALSM) method combined with the probability density function-bmsed ant colony optimization algorithm (PDF-ACO) is proposed for retrieval of aerosol optical constants. An optimal... An angular light-scattering measurement (ALSM) method combined with the probability density function-bmsed ant colony optimization algorithm (PDF-ACO) is proposed for retrieval of aerosol optical constants. An optimal measurement angle selection method using a principal component analysis (PCA) approach is developed to improve retrieval accuracy. Results indicate that optimized angle selection can ensure retrieval accuracy. The aerosol optical constants over Beijing, China, which are available from the Aerosol Robotic Network (AERONET), are then rec on structed. The ALSM method's con vergence properties are also studied via comparison w让h those of the light reflection-transmittance measurement (LRTM) method. Results retrieved using the ALSM method show better convergence speed and accuracy than those retrieved using the LRTM method because the ALSM method does not require solution of the radiative transfer equation and allows more useful signals to be obtained. Additionally, the inverse accuracy of the refractive index results is better than that of the absorption index results;this is attributed to differences between the monodromic characteristics of the refractive index and absorption index retrieval results. All results confirm that the combination of the ALSM method w让h the PDF-ACO algorithm and the optimal measurement angle selection method provides effective and reliable aerosol optical constant reconstructio n. 展开更多
关键词 ANGULAR LIGHT-SCATTERING MEASUREMENT method AEROSOL optical constant Ant COLONY optimization algorithm Principal comp ORIENT analysis Inverse radiation problem
Modeling river water quality parameters using modified adaptive neuro fuzzy inference system 预览
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作者 Armin Azad Hojat Karami +2 位作者 Saeed Farzin Sayed-Farhad Mousavi Ozgur Kisi 《水科学与水工程:英文版》 EI CAS CSCD 2019年第1期45-54,共10页
Water quality is always one of the most important factors in human health. Artificial intelligence models are respected methods for modeling water quality. The evolutionary algorithm (EA) is a new technique for improv... Water quality is always one of the most important factors in human health. Artificial intelligence models are respected methods for modeling water quality. The evolutionary algorithm (EA) is a new technique for improving the performance of artificial intelligence models such as the adaptive neuro fuzzy inference system (ANFIS) and artificial neural networks (ANN). Attempts have been made to make the models more suitable and accurate with the replacement of other training methods that do not suffer from some shortcomings, including a tendency to being trapped in local optima or voluminous computations. This study investigated the applicability of ANFIS with particle swarm optimization (PSO) and ant colony optimization for continuous domains (ACOR) in estimating water quality parameters at three stations along the Zayandehrood River, in Iran. The ANFIS-PSO and ANFIS-ACOR methods were also compared with the classic ANFIS method, which uses least squares and gradient descent as training algorithms. The estimated water quality parameters in this study were electrical conductivity (EC), total dissolved solids (TDS), the sodium adsorption ratio (SAR), carbonate hardness (CH), and total hardness (TH). Correlation analysis was performed using SPSS software to determine the optimal inputs to the models. The analysis showed that ANFIS-PSO was the better model compared with ANFIS-ACOR. It is noteworthy that EA models can improve ANFIS' performance at all three stations for different water quality parameters. 展开更多
关键词 Water quality parameters ANFIS EVOLUTIONARY algorithm Particle SWARM OPTIMIZATION Ant COLONY OPTIMIZATION for continuous DOMAINS
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Private Medical Practice: The Gold Coast Colony’s Christiansborg Infant Welfare Clinic 预览
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作者 Doris Susannah Essah 《文化与宗教研究:英文版》 2018年第9期531-538,共8页
As the British colonized West Africa, Africans worked as medical officers. John Farrell Easmon practiced private medicine that in 1897 affected his work as the chief medical officer. The Secretary of State for the Col... As the British colonized West Africa, Africans worked as medical officers. John Farrell Easmon practiced private medicine that in 1897 affected his work as the chief medical officer. The Secretary of State for the Colonies Joseph Chamberlain investigated the complaints of medical officers and fashioned the policy of the West African Medical Staff in 1902. During the Great Depression, the West African Medical Staff and Staff Pay shaped how African medical officers and European women medical doctors earned salaries as colonial government workers. Percy Selwyn-Clarke the deputy director of health service employed European women medical doctors in preventive health at infant and child welfare clinics. In 1935, health visitor Christian challenged the government for paying European woman medical doctor Nora Vane-Percy £10 to treat destitute African women and children at the Christiansborg infant welfare clinic. 展开更多
关键词 PRIVATE MEDICAL practice European women MEDICAL DOCTORS health visitors Africanization the GOLD Coast COLONY Christiansborg 1920s 1930s
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Improved Ant Colony-Genetic Algorithm for Information Transmission Path Optimization in Remanufacturing Service System
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作者 Lei Wang Xu-Hui Xia +2 位作者 Jian-Hua Cao Xiang Liu Jun-Wei Liu 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2018年第6期106-117,共12页
The information transmission path optimization(ITPO) can often a ect the e ciency and accuracy of remanufactur?ing service. However, there is a greater degree of uncertainty and complexity in information transmission ... The information transmission path optimization(ITPO) can often a ect the e ciency and accuracy of remanufactur?ing service. However, there is a greater degree of uncertainty and complexity in information transmission of remanu?facturing service system, which leads to a critical need for designing planning models to deal with this added uncer?tainty and complexity. In this paper, a three?dimensional(3D) model of remanufacturing service information network for information transmission is developed, which combines the physic coordinate and the transmitted properties of all the devices in the remanufacturing service system. In order to solve the basic ITPO in the 3D model, an improved 3D ant colony algorithm(Improved AC) was put forward. Moreover, to further improve the operation e ciency of the algorithm, an improved ant colony?genetic algorithm(AC?GA) that combines the improved AC and genetic algorithm was developed. In addition, by taking the transmission of remanufacturing service demand information of certain roller as example, the e ectiveness of AC?GA algorithm was analyzed and compared with that of improved AC, and the results demonstrated that AC?GA algorithm was superior to AC algorithm in aspects of information transmission delay, information transmission cost, and rate of information loss. 展开更多
关键词 REMANUFACTURING service Information transmission PATH optimization ANT COLONY ALGORITHM GENETIC ALGORITHM
解淀粉芽孢杆菌ZJ01对枣黑斑病菌的抑制作用 预览
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作者 李扬 张朝红 +2 位作者 于秋香 李杰 张献辉 《河北农业科学》 2018年第4期40-42,共3页
为了有效防控枣黑斑病,以解淀粉芽孢杆菌 ZJ01 为试材,进行了枣黑斑病菌 LG 与解淀粉芽孢杆菌ZJ01的平板对峙和玻片对峙试验,观察了解淀粉芽孢杆菌 ZJ01 对枣黑斑病菌 LG 菌落生长及孢子萌发的抑制效果.结果表明:平板对峙培养 8 d 时,... 为了有效防控枣黑斑病,以解淀粉芽孢杆菌 ZJ01 为试材,进行了枣黑斑病菌 LG 与解淀粉芽孢杆菌ZJ01的平板对峙和玻片对峙试验,观察了解淀粉芽孢杆菌 ZJ01 对枣黑斑病菌 LG 菌落生长及孢子萌发的抑制效果.结果表明:平板对峙培养 8 d 时,解淀粉芽孢杆菌 ZJ01 对枣黑斑病菌 LG 菌落生长有较强的抑制作用,抑制率达到 53.3%;对峙区的枣黑斑病菌 LG 菌丝出现了顶端膨大、原生质割裂、不正常产孢等异常现象.解淀粉芽孢杆菌 ZJ01 无菌发酵液可有效抑制枣黑斑病菌LG 的孢子萌发及菌丝生长. 展开更多
关键词 解淀粉芽孢杆菌 枣树 枣黑斑病 抑制作用 菌落 孢子
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A Perspective of Conventional and Bio-inspired Optimization Techniques in Maximum Likelihood Parameter Estimation 预览
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作者 Yongzhong Lu Min Zhou +3 位作者 Shiping Chen David Levy Jicheng You Danping Yan 《自主智能(英文)》 2018年第2期1-12,共12页
Maximum likelihood estimation is a method of estimating the parameters of a statistical model in statistics. It has been widely used in a good many multi-disciplines such as econometrics, data modelling in nuclear and... Maximum likelihood estimation is a method of estimating the parameters of a statistical model in statistics. It has been widely used in a good many multi-disciplines such as econometrics, data modelling in nuclear and particle physics, and geographical satellite image classification, and so forth. Over the past decade, although many conventional numerical approximation approaches have been most successfully developed to solve the problems of maximum likelihood parameter estimation, bio-inspired optimization techniques have shown promising performance and gained an incredible recognition as an attractive solution to such problems. This review paper attempts to offer a comprehensive perspective of conventional and bio-inspired optimization techniques in maximum likelihood parameter estimation so as to highlight the challenges and key issues and encourage the researches for further progress. 展开更多
关键词 maximum LIKELIHOOD estimation BIO-INSPIRED OPTIMIZATION differential evolution SWARM intelligence-based ALGORITHM genetic ALGORITHM particle SWARM OPTIMIZATION ant COLONY optimization.
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香菇和杏鲍菇培养基pH值条件和营养液浓度的优化 预览
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作者 胡敏 杜宝海 +3 位作者 毕晓娟 孙猛 林佳莹 孟祥森 《天津农业科学》 CAS 2018年第9期49-51,共3页
为优化香菇和杏鲍菇两种食用菌生长的培养基条件,对不同pH值和营养液浓度下菌丝形态和菌落的生长状态进行研究,筛选适宜两种食用菌生长的pH值条件和营养液浓度。结果表明,香菇和杏鲍菇培养液的最适pH值分别为8.0和6.0,最适培养液浓度均... 为优化香菇和杏鲍菇两种食用菌生长的培养基条件,对不同pH值和营养液浓度下菌丝形态和菌落的生长状态进行研究,筛选适宜两种食用菌生长的pH值条件和营养液浓度。结果表明,香菇和杏鲍菇培养液的最适pH值分别为8.0和6.0,最适培养液浓度均为0.6%,在此条件下,菌丝生长速度快,横隔多,锁状联合密集,液泡和细胞核明显。 展开更多
关键词 香菇 杏鲍菇 培养条件 菌丝形态 菌落
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Optimized design of collector topology for offshore wind farm based on ant colony optimization with multiple travelling salesman problem 预览
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作者 Ramu SRIKAKULAPU Vinatha U 《现代电力系统与清洁能源学报(英文)》 2018年第6期1181-1192,共12页
A layout of the offshore wind farm(OSWF)plays a vital role in its capital cost of installation. One of the major contributions in the installation cost is electrical collector system(ECS). ECS includes: submarine cabl... A layout of the offshore wind farm(OSWF)plays a vital role in its capital cost of installation. One of the major contributions in the installation cost is electrical collector system(ECS). ECS includes: submarine cables,number of wind turbines(WTs), offshore platforms etc. By considering the above mentioned problem having an optimized design of OSWF provides the better feasibility in terms of economic considerations. This paper explains the methodology for optimized designing of ECS. The proposed methodology is based on combined elitist ant colony optimization and multiple travelling salesman problem.The objective is to minimize the length of submarine cable connected between WTs and to minimize the wake loss in the wind farm in order to reduce the cost of cable and cable power loss. The methodology is applied on North Hoyle and Horns Rev OSWFs connected with 30 and 80 WTs respectively and the results are presented. 展开更多
关键词 Ant COLONY optimization Offshore wind farm MULTIPLE TRAVELLING SALESMAN problem WAKE effect WAKE loss
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The Tamale Local Boy Scouts Association in the Northern Territories Protectorate in the 1920s 预览
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作者 Doris S.Essah 《文化与宗教研究:英文版》 2018年第6期367-375,共9页
In 1907,military leader Robert Baden-Powell started the Boy Scouts Association in England as the British colonial government officers instituted Tamale village as the administrative centre of the Northern Territories ... In 1907,military leader Robert Baden-Powell started the Boy Scouts Association in England as the British colonial government officers instituted Tamale village as the administrative centre of the Northern Territories Protectorate.Sam Yarney worked with Frank Collyer the European bank cashier and scoutmaster who started the Boy Scouts in the Gold Coast Colony in 1914,the year the First World War started.In 1922,Governor Gordon Guggisberg,who was brigadier general during the war was the chief scout.He reorganized the Local Boy Scouts Association in the Tamale Government School that received select boys from various schools in the Northern Territories Protectorate.The schoolboys excelled in the Standard VII and Civil Service Examinations to work with the government institutions and train as teachers and telegraphists.Arthur James Philbrick the chief scout commissioner of the Northern Territories employed Yarney as the assistant scout commissioner in the Southern Province to take on the staff of the reorganized Tamale Local Boy Scouts Association and register the 1st Tamale Troop.The scout officers subscribed to a Scout Fund to buy kit,for the schoolboys who passed the Tenderfoot Tests to buy uniforms and perform at events. 展开更多
关键词 LOCAL BOY Scouts ASSOCIATION 1920s uniforms Tamale GOVERNMENT School Northern TERRITORIES Protectorate Gold Coast COLONY
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扰动强度对太湖水华微囊藻群体生长和叶绿素荧光的影响 预览 被引量:1
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作者 韩丽华 杨桂军 +3 位作者 刘玉 秦伯强 钟春妮 杨宏伟 《环境科学研究》 CSCD 北大核心 2018年第2期265-272,共8页
风浪扰动在湖泊和水库中频繁发生,是影响湖泊生态系统的重要因素之一.为了解太湖风浪扰动对水华微囊藻群体生长的影响,并探究其影响机理,利用室内摇床试验,设置不同的扰动强度(0、50、100、200、400 r min)来模拟太湖风浪扰动,扰动时间... 风浪扰动在湖泊和水库中频繁发生,是影响湖泊生态系统的重要因素之一.为了解太湖风浪扰动对水华微囊藻群体生长的影响,并探究其影响机理,利用室内摇床试验,设置不同的扰动强度(0、50、100、200、400 r min)来模拟太湖风浪扰动,扰动时间为24 h,并测定不同扰动强度下水华微囊藻群体生长和叶绿素荧光参数.结果表明,所有试验组中,100 r min组的ρ(Chla)、微囊藻数量、F v F m(潜在最大光合效率)、ETR max(潜在最大光合速率)、I k(半饱和光强)和α(光能利用效率)增加最快,试验结束时分别为扰动前的3.29、10.75、1.20、2.30、2.21和1.21倍;并且扰动结束后,100 r min组中3~10细胞群体细胞数量占比由25.80%降至20.70%,显著低于对照组(P<0.05),而>10细胞群体细胞数量占比由0增至25.55%,显著高于对照组(P<0.05).方差分析表明,试验第7~11天,100 r min组的ρ(Chla)、水华微囊藻数量、F v F m、ETR max和α显著高于对照组(P<0.05);第1~5天,400 r min组的ρ(Chla)、ETR max和I k显著低于对照组(P<0.05).研究显示,适宜的扰动强度(100 r min)促进水华微囊藻群体生长和光合活性,过高的扰动强度(400 r min)则抑制水华微囊藻群体生长和光合活性. 展开更多
关键词 水华微囊藻 群体 扰动强度 叶绿素荧光 太湖
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