基于随机收敛因子和差分变异的改进灰狼优化算法

针对基本灰狼优化算法在求解高维复杂优化问题时存在解精度低和易陷入局部最优的缺点,提出一种改进的灰狼优化算法。受粒子群优化算法的启发,设计一种收敛因子a随机动态调整策略以协调算法的全局勘探和局部开采能力;为了增强种群多样性和降低算法陷入局部最优的概率,受差分进化算法的启发,构建一种随机差分变异策略产生新个体。选取6个标准测试函数进行仿真实验。结果表明:在相同的适应度函数评价次数条件下,此算法在求解精度和收敛速度上均优于其他算法。     

求解全局优化问题的改进灰狼算法

灰狼算法是一种高效的优化技术,但其在一些问题上存在求解精度不高、收敛速度较慢和易于陷入局部最优的缺点。因此,提出了一种改进的灰狼优化算法（MGWO）。该算法引入了3种改进策略：平衡算法全局搜索性和局部开发性的指数规律收敛因子调整策略、提高算法求解精度的自适应位置更新策略和修订动态权重策略。通过两组在10个基准测试函数上的对比实验,验证3种改进策略的有效性。实验结果表明,综合使用3种策略的MGWO_4明显提升了基本灰狼算法（GWO）的性能,而且优于其他文献中的改进灰狼算法和其他数个优化算法。最后,在工程设计问题上的实验结果进一步证明了MGWO高效的寻优能力。     

求解函数优化和特征选择的改进金豺狼优化算法

针对基本金豺狼优化算法(Golden Jackal Optimization, GJO)在解决高维优化问题时存在计算精度低、开发能力弱、容易陷入局部最优的缺点,提出一种改进GJO算法(I-GJO)。在改进算法中,设计一种基于正弦函数的非线性能量因子替代原随机递减能量因子,以平衡算法在搜索过程中的全局探索和局部开发能力。在算法迭代后期引入翻筋斗学习策略,从而扩大群体搜索范围和改善解的精度。为了验证I-GJO算法的有效性,选取6个基准函数优化问题进行数值实验,并与灰狼优化、海鸥优化算法和基本GJO算法比较。结果表明,I-GJO获得较高的精度和较快的收敛速度。最后利用I-GJO算法求解特征选择问题,对16个基准数据集的数值结果显示,改进算法能有效去除冗余特征和提高分类精度。     

嵌入遗传算子的改进灰狼优化算法

针对基本灰狼优化算法(GWO)存在求解精度低、后期收敛速度慢和易陷入局部最优的问题,提出一种基于遗传算子的改进灰狼优化(IGWO)算法用于求解无约束优化问题.该算法首先利用佳点集理论初始化种群,为算法全局搜索多样性奠定基础;然后在决策层以外的群体中随机选取三个个体与决策层个体执行算术交叉操作,引导群体向决策层区域移动以增强算法局部搜索能力和加快算法收敛速度;最后,对决策层个体进行多样性变异操作以避免算法陷入局部最优.采用几个标准测试函数进行仿真实验:当维数较高(D=30或D=50)时,IGWO算法的总体性能上均优于基本GWO算法.实验结果表明IGWO算法在收敛速度和求解精度指标上明显优于对比算法.     

改进收敛因子和变异策略的灰狼优化算法

针对灰狼优化算法(GWO)在求解复杂优化问题时容易出现收敛速度慢和早熟收敛等缺点,提出了一种改进收敛因子和变异策略的新型灰狼优化算法(CMGWO)。为了平衡GWO算法的全局探索能力与局部开发能力,设计了一种基于反余弦函数变化策略的收敛因子;为了进一步提高算法跳出局部最优解的能力,提出了一种新的位置变异策略。仿真实验结果表明,与已有的3种智能优化算法和5种典型改进灰狼优化算法相比,改进算法具有更快的收敛速度和更高的寻优精度,更适用于解决各种函数优化问题。     

基于改进蝗虫优化算法的特征选择方法

针对传统蝗虫优化算法寻优精度低和收敛速度慢的问题,提出一种基于非线性调整策略的改进蝗虫优化算法.首先,利用非线性参数代替传统蝗虫算法中的递减系数,协调算法全局探索和局部开发能力,加快算法收敛速度;其次,引入自适应权重系数改变蝗虫位置更新方式,提高算法寻优精度;然后,结合limit阈值思想,利用非线性参数对种群中部分个体进行扰动,避免算法陷入局部最优.通过六个基准测试函数的仿真结果表明,改进算法的收敛速度和寻优精度均有明显提高.最后将改进算法应用于特征选择问题中,通过在七个数据集上的实验结果表明,基于改进算法的特征选择方法能够有效地进行特征选择,提高分类准确率.     

基于莱维飞行和布朗运动的鲸鱼优化算法

针对鲸鱼优化算法存在的求解精度不高、收敛速度较慢和易陷入局部最优等缺点，设计了一种基于莱维飞行和布朗运动的鲸鱼优化算法.先利用莱维飞行方法对鲸鱼种群进行初始化，以增加初始种群的多样性；再根据布朗运动原理对鲸鱼种群的位置更新进行随机扰动，以避免算法提前陷入局部最优.将改进的鲸鱼优化算法与鲸鱼优化算法、粒子群优化算法、遗传算法和蚁群优化算法在7个不同的基准测试函数上进行对比测试，结果表明，改进的鲸鱼优化算法在求解精度、收敛速度方面均优于其他4种算法.对初始化阶段采用莱维飞行策略的改进鲸鱼优化算法与采用随机搜索策略的鲸鱼优化算法的初始解探索范围进行仿真对比实验，结果表明，改进鲸鱼优化算法一定程度上可以避免陷入局部最优.     

基于自适应头狼的灰狼优化算法

灰狼优化算法一种模拟灰狼捕食行为的元启发式优化算法.由于灰狼算法在种群迭代更新中始终靠近最优解,所以易陷入局部最优.提出了一种基于自适应头狼的灰狼优化算法,并在个体迭代更新中选择合适的头狼个数进行个体更新,这使得算法能够平衡开发和勘探能力.通过对20个基准函数优化问题的仿真实验表明,改进后的算法与原始灰狼优化算法相比,其全局搜索能力有显著提高.     

动态透镜成像学习人工兔优化算法及应用

针对基本人工兔优化(Artificial Rabbits Optimization, ARO)算法在解决复杂优化问题时存在收敛慢、精度不高和容易陷入局部最优等缺陷,本文提出一种改进的ARO算法(记为IARO算法)。IARO算法中的基于正弦函数的非线性递减能量因子能够帮助算法实现从探索阶段到开发阶段的良好过渡,从而提高算法的收敛速度和解的质量。此外,为了提高算法跳出局部最优的概率,IARO算法引入了一种动态透镜成像学习策略。为了证明IARO算法的优越性,首先选取了6个基准测试函数进行数值实验,然后用其求解2个工程设计优化问题和1个包括15个数据集的特征选择问题,并与灰狼优化(GWO)算法、鲸鱼优化算法(WOA)、正弦余弦算法(SCA)和基本ARO算法进行对比。结果表明,IARO算法有着比其他对比算法更优越的性能。     

基于改进灰狼优化算法的区域监测机器人路径规划

为了解决大任务量作业监测中机器人路径规划问题,提出了一种区域监测的机器人路径规划算法。模拟大任务量监测真实环境进行问题建模。针对传统灰狼优化算法求解模型时全局搜索能力差且易陷入局部最优解的问题,提出了一种改进的灰狼优化算法。引入Logistic混沌映射,以加强初始化种群的多样性;引入一种控制参数的自适应调整策略,以平衡灰狼优化算法的搜索能力和开发能力;引入静态加权平均权重策略,更新种群位置,加快收敛速度。将机器人载电量与路径长度短作为约束,引入K-means算法进行任务聚类,通过改进灰狼优化算法对模型进行离线求解以规划出路径,将大任务量监测作业自动转换成分时分步作业。实验结果表明:通过国际通用6个基准函数进行测试,改进的灰狼优化算法在收敛速度、搜索精度及稳定性上均有明显提高。通过50任务点与100任务点作业场景对机器人路径规划模型进行算法仿真,验证了算法的真实有效性,且任务量越大模型优越性越好,路径缩短比例越高。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the