Constrained differential evolution with multiobjective sorting mutation operators for constrained optimization

Differential evolution (DE) is a simple and powerful evolutionary algorithm for global optimization. DE with constraint handling techniques, named constrained differential evolution (CDE), can be used to solve constrained optimization problems (COPs). In existing CDEs, the parents are randomly selected from the current population to produce trial vectors. However, individuals with fitness and diversity information should have more chances to be selected. This study proposes a new CDE framework that uses nondominated sorting mutation operator based on fitness and diversity information, named MS-CDE. In MS-CDE, firstly, the fitness of each individual in the population is calculated according to the current population situation. Secondly, individuals in the current population are ranked according to their fitness and diversity contribution. Lastly, parents in the mutation operators are selected in proportion to their rankings based on fitness and diversity. Thus, promising individuals with better fitness and diversity are more likely to be selected as parents. The MS-CDE framework can be applied to most CDE variants. In this study, the framework is applied to two popular representative CDE variants, (μ + λ)-CDE and ECHT-DE. Experiment results on 24 benchmark functions from CEC’2006 and 18 benchmark functions from CEC’2010 show that the proposed framework is an effective approach to enhance the performance of CDE algorithms.     

Leveraging diverse knowledge sources through proactive behaviour: How companies can use inter‐organizational networks for business model innovation

The relevance of business model innovation (BMI) for strategic renewal and competitive advantage has been increasingly recognized by both strategy scholars and managers. In this paper, we explore how inter‐organizational networks and firms' proactiveness influence BMI. By examining Dutch design companies, we show that having a network of companies with different sizes has a positive effect on BMI. We also observe a positive effect of ties change. Finally, we show the importance of firms' proactiveness. Through the discussion of network elements and proactiveness as antecedents of BMI, we contribute to the business model and social network literature.     

新闻与大众传播教育的现状和发展趋势——以对美国新闻与大众传播院系教师的抽样调查为例

本文是对美国30所新闻与大众传播院系的教师进行抽样调查的报告。探讨的主要问题包括当前美国新闻与传播教育的教学内容与教学手段、教学与科技发展的情况以及未来发展的趋势。结论主要可以概括为：科技为新闻与大众传播教育带来新挑战,基本理念、基本技能地位岿然不动,多样化是其发展的必然趋势。     

基于动态权值的粒子群算法的多样性分析

种群的多样性是保证粒子群优化算法收敛的前提条件,基于此提出了一个概念清晰、运算量小的多样性定义,并从粒子在寻优过程中粒子聚合程度和速度进化程度出发分析粒子群的多样性。在此基础上,提出了一种基于动态权值的改进算法,算法能自适应的调整惯性因子以保持种群多样性,有效地避免了早熟收敛。仿真实验表明该算法不仅能加快种群的进化速度,而且还能增强算法的全局收敛性,收敛概率也从15％增加到100％。     

对山东省经济发展水平区域划分的探讨

区域经济差异是经济发展过程中出现的一个普遍的问题，它直接影响着社会的安定和人民的生活水平。本文采用因子分析和聚类分析相结合的方法，结合山东省的具体情况将总体分为发达地区、相对落后地区和异常地区三类。     

Triple band notched mushroom and uniplanar EBG structures based UWB MIMO/Diversity antenna with enhanced wide band isolation

Triple band-rejection MIMO/Diversity UWB antenna characteristics are described in this paper. Proposed antenna discards worldwide interoperability for microwave access WiMAX band from 3.3 to 3.6 GHz, wireless local area network WLAN band from 5 to 6 GHz and X-Band satellite downlink communication band from 7.1 to 7.9 GHz. Mushroom Electromagnetic Band Gap (EBG) structures helps to attain band notches in WiMAX and WLAN bands. Uniplanar plus shaped EBG structure is used for notch in X-band downlink satellite communication band. Decoupling strips and slotted ground plane are employed to develop the isolation among two closely spaced UWB monopoles. The individual monopoles are 90° angularly separated with stepped structure which helps to reduce mutual coupling and also contributes towards impedance matching by increasing current path length. Mutual coupling magnitude of more than 15 dB is found over whole UWB frequency range. The Envelope Correlation Coefficient is less than 0.02 over whole UWB frequency range.The variations in the notched frequency with the variations in mushroom EBG structure parameters are investigated.The antenna has been designed using FR-4 substrate and overall dimensions is (64 × 45 × 1.6) mm³.     

大众化体育建筑的多元发展

本文探讨了新时期体育建筑的大众化发展理念,对体育建筑的理性决策、适用技术、多元化发展及对特殊人群的关注等方面进行了分析,阐述了大众化体育建筑和谐多元、科学有序的发展方向。"     

Effects of microelements on soil nematode assemblages seven years after contaminating an agricultural field

Long-term effects of Cd, Cr, Cu, Se and Zn were studied 7 years after artificially contaminating plots of an agricultural field on a calcareous chernozem soil. Effects of three to four different contamination levels (originally 10, 30, 90 and 270 mg kg⁻¹) were studied. Nematode density was significantly reduced by 90 and 270 mg kg⁻¹ Se as well as by 270 mg kg⁻¹ Cr, while 90 and 270 mg kg⁻¹ Se also reduced nematode generic richness. Maturity Index values (calculated for c-p 2–5 nematodes) consistently decreased with increasing Cr and Se concentration and to a lesser extent in Zn plots as well. Structure Index showed decreasing trends in increasing Cr, Se and (to a lesser extent) in Zn treatments, while in Cd it shows a moderate increase. Distribution of c-p groups was negatively affected by the increasing Cr and Se concentration, while in Zn plots, this decrease was not significant. Response of feeding groups to pollutions was similar to other parameters: Cr and Se caused significant changes toward the loss of variability. The proportion of the most sensitive omnivorous and predatory nematodes decreased clearly as a consequence of Cr and Se treatments. Zn pollution also resulted in a slight decrease in this group, while Cd caused an increase. Nematode diversity profiles showed a significant decrease in the plots of increased Cr and Se concentrations, while increased concentrations of Cu and Zn resulted in ambiguous effects. Besides providing evidence on the harmful effects of Cr and Se on a soil nematode assemblage, our results suggest that simultaneous analysis of Maturity Index, Structure Index and diversity profiles provide a promising tool in nematological indication of soil pollution.     

乡土之路--杰佛里·巴瓦的风景园林设计探索之路解析

斯里兰卡著名建筑师与风景园林师杰佛里·巴瓦勇于探索建筑设计与风景园林设计的关系,其风景园林设计作品在国际风景园林界产生了很好的影响,有人称赞他为建筑与风景园林设计的结合,走出了成功的一步。他在经济并不发达、政治与民族关系纷繁复杂的斯里兰卡,默默无闻地执著工作,并最终获得成功,同时也得到世人的认可。巴瓦的才华是有目共睹的,他执著的精神和强烈的责任感,更加值得世人敬佩和学习。通过探讨他的设计理念和设计方法,试图从中找到其成功答案——如何走上乡土之路。