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A novel immiscible high entropy alloy strengthened via L1_(2)-nanoprecipitate
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作者 WANG Zheng-qin FAN Ming-yu +5 位作者 ZHANG Yang LI Jun-peng LIU Li-yuan HAN Ji-hong LI Xing-hao ZHANG Zhong-wu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期1808-1822,共15页
The low-cost Fe-Cu,Fe-Ni,and Cu-based high-entropy alloys exhibit a widespread utilization prospect.However,these potential applications have been limited by their low strength.In this study,a novel Fe_(31)Cu_(31)Ni_(... The low-cost Fe-Cu,Fe-Ni,and Cu-based high-entropy alloys exhibit a widespread utilization prospect.However,these potential applications have been limited by their low strength.In this study,a novel Fe_(31)Cu_(31)Ni_(28)Al_(4)Ti_(3)Co_(3) immiscible high-entropy alloy(HEA)was developed.After vacuum arc melting and copper mold suction casting,this HEA exhibits a unique phase separation microstructure,which consists of striped Cu-rich regions and Fe-rich region.Further magnification of the striped Cu-rich region reveals that it is composed of a Cu-rich dot-like phase and a Fe-rich region.The aging alloy is further strengthened by a L1_(2)-Ni_(3)(AlTi)nanoprecipitates,achieving excellent yield strength(1185 MPa)and uniform ductility(~8.8%).The differential distribution of the L1_(2) nanoprecipitate in the striped Cu-rich region and the external Fe-rich region increased the strength difference between these two regions,which increased the strain gradient and thus improved hetero-deformation induced(HDI)hardening.This work provides a new route to improve the HDI hardening of Fe-Cu alloys. 展开更多
关键词 heterogeneous microstructure precipitation strengthening high-entropy alloy phase separation mechanical property
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Short-term prediction of photovoltaic power generation based on LMD-EE-ESN with error correction
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作者 YU Xiangqian LI Zheng 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期360-368,共9页
Considering the instability of the output power of photovoltaic(PV)generation system,to improve the power regulation ability of PV power during grid-connected operation,based on the quantitative analysis of meteorolog... Considering the instability of the output power of photovoltaic(PV)generation system,to improve the power regulation ability of PV power during grid-connected operation,based on the quantitative analysis of meteorological conditions,a short-term prediction method of PV power based on LMD-EE-ESN with iterative error correction was proposed.Firstly,through the fuzzy clustering processing of meteorological conditions,taking the power curves of PV power generation in sunny,rainy or snowy,cloudy,and changeable weather as the reference,the local mean decomposition(LMD)was carried out respectively,and their energy entropy(EE)was taken as the meteorological characteristics.Then,the historical generation power series was decomposed by LMD algorithm,and the hierarchical prediction of the power curve was realized by echo state network(ESN)prediction algorithm combined with meteorological characteristics.Finally,the iterative error theory was applied to the correction of power prediction results.The analysis of the historical data in the PV power generation system shows that this method avoids the influence of meteorological conditions in the short-term prediction of PV output power,and improves the accuracy of power prediction on the condition of hierarchical prediction and iterative error correction. 展开更多
关键词 photovoltaic(PV)power generation system short-term forecast local mean decomposition(LMD) energy entropy(EE) echo state network(ESN)
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架一道人文彩虹在心灵深处——我教《熵:一种新的世界观》
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作者 卢真福 《中学语文(教学大参考)(上旬)》 2006年第2期32-34,共3页
新课改之后.语文界开始重视跨学科的学习,教材中也相应选入科普文章。有的老师在教学过程中花大量时间介绍科学术语和相关知识,却脱离对文本语言的研究,忘却语文学科的人文性,把语文课上成了科学课。其结果,教师教得艰难、呆板,... 新课改之后.语文界开始重视跨学科的学习,教材中也相应选入科普文章。有的老师在教学过程中花大量时间介绍科学术语和相关知识,却脱离对文本语言的研究,忘却语文学科的人文性,把语文课上成了科学课。其结果,教师教得艰难、呆板,学生学得空洞、乏味。 展开更多
关键词 《熵:一种新的世界观》 人文性 心灵 彩虹 语文学科 科普文章 相关知识 科学术语 教学过程 文本语言
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一“字”激起千层浪——《熵:一种新的世界观》解读
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作者 王松泉 曹颖群 《中学语文(教师版)》 2004年第3期23-25,共3页
高中语文第六册第一单元的四篇课文中,除了梁思成的《千篇一律与千变万化》,其余三篇都是不折不扣的科技论说文,篇幅既长,难度亦深——科学术语频率较高,论述也采用科学家思维特有的方式——学生阅读时极可能因知识或思维的断层而... 高中语文第六册第一单元的四篇课文中,除了梁思成的《千篇一律与千变万化》,其余三篇都是不折不扣的科技论说文,篇幅既长,难度亦深——科学术语频率较高,论述也采用科学家思维特有的方式——学生阅读时极可能因知识或思维的断层而出现理解的困难。要帮助学生解决这些困难,教师自己首先要能读懂读深读透文本。 展开更多
关键词 《熵:一种新的世界观》 高中 语文教学 第六册 第一单元 阅读指导
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Prediction of rock burst classification using cloud model with entropy weight 被引量:28
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作者 周科平 林允 +2 位作者 邓红卫 李杰林 刘传举 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1995-2002,共8页
The method of cloud model with entropy weight was adopted for the prediction of rock burst classification. Some main factors of rock burst including the uniaxial compressive strength (σc), the tensile strength (σ... The method of cloud model with entropy weight was adopted for the prediction of rock burst classification. Some main factors of rock burst including the uniaxial compressive strength (σc), the tensile strength (σt), the tangential stress (σθ), the rock brittleness coefficient (σc/σt), the stress coefficient (σθ /σc) and the elastic energy index (Wet) are chosen to establish evaluation index system. The entropy?cloud model and criterion are obtained through 209 sets of rock burst samples from underground rock projects. The sensitivity of indicators is analyzed and 209 sets of rock burst samples are discriminated by this model. The discriminant results of the entropy-cloud model are compared with those of Bayes, KNN and RF methods. The results show that the sensitivity order of those factors from high to low is σ_θ /σ_c, σ_θ, W_(ct), σ_c/σ_t, σ_t, σ_c, and the entropy-cloud model has higher accuracy than Bayes, K-Nearest Neighbor algorithm (KNN) and Random Forest (RF) methods. 展开更多
关键词 rock burst PREDICTION cloud model entropy weight sensitivity
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Effect of minor B addition on microstructure and properties of AlCoCrFeNi multi-compenent alloy 被引量:11
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作者 陈秋实 卢一平 +2 位作者 董勇 王同敏 李廷举 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第9期2958-2964,共7页
The influences of slight amount of B element on the microstructure and properties of AlCoCrFeNiBx high entropy alloys(x = 0,0.01,…,0.09 and 0.1,mole fraction) were investigated.The AlCoCrFeNi high entropy alloy exh... The influences of slight amount of B element on the microstructure and properties of AlCoCrFeNiBx high entropy alloys(x = 0,0.01,…,0.09 and 0.1,mole fraction) were investigated.The AlCoCrFeNi high entropy alloy exhibits equiaxed grain structures with obvious composition segregation.However,with the addition of B element,the alloys exhibit dendrite structures.Inside the dendrites,spinodal decomposition structure can be clearly observed.With the addition of B element,the crystal structures change from(B2 + BCC) to(B2 + BCC + FCC) structures,and the hardness firstly increases from HV 486.7 to HV 502.4,then declines to HV 460.7(x ≥ 0.02).The compressive fracture strength firstly shows a trend of increasing,and then declining(x ≥ 0.08).The coercive forces and the specific saturation magnetizations of the alloys decrease as B addition contents increase,the decreasing coercive forces show a better soft magnetic behavior. 展开更多
关键词 high entropy alloy B element microstructure compressive properties HARDNESS magnetic properties
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First principles calculation of intermetallic compounds in FeTiCoNiVCrMnCuAl system high entropy alloy 被引量:10
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作者 农智升 朱景川 +1 位作者 于海玲 来忠红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1437-1444,共8页
The structural, electronic and elastic properties of common intermetallic compounds in FeTiCoNiVCrMnCuAI system high entropy alloy were investigated by the first principles calculation. The calculation results of form... The structural, electronic and elastic properties of common intermetallic compounds in FeTiCoNiVCrMnCuAI system high entropy alloy were investigated by the first principles calculation. The calculation results of formation enthalpy and cohesive energy show that FeTi, Fe2Ti, AlCrFe2, Co2Ti, AlMn2V and Mn2Ti phases may form in the formation process of the alloy. Further studies show that FeTi, FezTi, AlCrFe2, Co2Ti and AlMn2V phases with higher shear modulus and elastic modulus would be excellent strengthening phases in high entropy alloy and would improve the hardness of the alloy. In addition, the partial density of states was investigated for revealing the bonding mode, and the analyses on the strength of p-d hybridization also reveal the underlying mechanism for the elastic properties of these compounds. 展开更多
关键词 FeTiCoNiVCrMnCuA1 system high entropy alloy first principles calculation phase stability
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Formation condition of solid solution type high-entropy alloy 被引量:22
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作者 任明星 李邦盛 傅恒志 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期991-995,共5页
Formation condition of high-entropy alloys with solid solution structure was investigated. Seventeen kinds of the high-entropy alloys with different components were prepared, the influencing factors (the comprehensiv... Formation condition of high-entropy alloys with solid solution structure was investigated. Seventeen kinds of the high-entropy alloys with different components were prepared, the influencing factors (the comprehensive atomic radius difference δ, the mixing enthalpy AH and the mixing entropy AS) of phase composition of the alloys were calculated, and the microstructure and phase compositions of alloys were analyzed by using SEM and XRD. The result shows that only the systems with δ≤2.77 and △H≥-8.8 kJ/mol will form high entropy alloy with simple solid solution. Otherwise, intermetallic compounds will exist in the alloys. So, selection of the type of element has important effects on microstructure and properties of high entropy alloys. 展开更多
关键词 high entropy alloy solid solution comprehensive atomic radius difference mixing enthalpy formation condition
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An Entropy-based Index for Fine-scale Mapping of Disease Genes 被引量:2
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作者 李玉梅 向阳 +1 位作者 邓红文 孙振球 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第7期661-668,共8页
By comparing the entropy and the conditional entropy in a marker, an entropy-based index has been presented for fine-scale linkage disequilibrium gene mapping using high-density marker maps for human disease genes. Th... By comparing the entropy and the conditional entropy in a marker, an entropy-based index has been presented for fine-scale linkage disequilibrium gene mapping using high-density marker maps for human disease genes. The index can quantify the level of linkage disequilibrium (LD) between the marker and the disease susceptibility locus (DSL) of genes. The advantage of using the index is attributed to the fact that it does not depend on marker allele frequencies across loci. Moreover, it is parallel to Hardy-Weinberg disequilibrium (HWD) measure for DSL fine mapping. Through various simulations, the fine mapping perform- ances of the proposed entropy-based index was extensively investigated under various genetic parameters. The results show that the index presented is both robust and powerful for DSL mapping in genes. 展开更多
关键词 ENTROPY entropy-based index fine mapping
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Application of Fuzzy Comprehensive Evaluation Method Based on Entropy Weight Theory in Evaluation of Salt Tolerance of Cotton 被引量:6
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作者 张国伟 刘瑞显 +1 位作者 杨长琴 杨富强 《Agricultural Science & Technology》 CAS 2014年第9期1441-1445,1481,共6页
[Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of ... [Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of cotton. [Method] A sand culture experiment under salt stress of 150 mmol/L of NaCI was designed. The in- dicator weight was determined with the entropy weight fuzzy comprehensive evalu- ation method, based on the salt injury index of indicators. The salt tolerance of cotton was evaluated comprehensively. [Result] At the germination stage, the entropy and weight of salt injury index of germination energy, vigor index, hypocotyl length and fresh weight were highest, followed by germination rate and germination index, and of root length were lowest. At the seedling stage, the entropy and weight of salt injury index of plasma membrane permeability, root vigor and leaf expansion rate were highest, followed by plant height and net photosynthetic rate, and of shoot dry weight and root dry weight were lowest. The salt tolerance of cotton differed a- mong growth stages and cultivars. Among the 11 cultivars, CCRI-44 and CCRI-75 were steadily salt-tolerant at both germination and seedling stages; CCRI-17, Sumi- an 22, Sumian 15 and Dexiamianl had a stable moderate salt tolerance; while Sumian 12 and Simian 3 were steadily salt-sensitive. [Conclusion] The evaluated result was objective and exact, which indicated that this method could be used in comprehensive evaluation of salt tolerance of cotton. 展开更多
关键词 Entropy weight method Fuzzy comprehensive evaluation COTTON Salt tolerance
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Intra-annual Vegetation Change Characteristics in the NDVI-Ts Space:Application to Farming-Pastoral Zone in North China 被引量:6
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作者 陈云浩 李晓兵 +2 位作者 史培军 窦闻 李霞 《Acta Botanica Sinica》 CSCD 2003年第10期1139-1145,共7页
Land use/land cover change (LUCC) mapping and analysis using multi-temporal normalize difference vegetation index (NDVI) data have been well documented. Recent empirical studies have documented that many new methods w... Land use/land cover change (LUCC) mapping and analysis using multi-temporal normalize difference vegetation index (NDVI) data have been well documented. Recent empirical studies have documented that many new methods with high accuracy of retrieved land surface temperature ( Ts) have been developed. Thus, the combination of land surface temperature and NDVI has the greatest potential to improve the surface vegetation dynamic monitoring. In this study, the following objectives are pursued to: (1) introduce the practical method to produce the Ts, NDVI and Ts/NDVI based on remotely sensed data; (2) investigate the different retrieved result of vegetation cover information from NDVI, Ts and Ts/NDVI data sets, and analyze the intra-annual time trajectories of different vegetation cover categories in the NDVI- Ts space for farming-pastoral zone in North China, and (3) quantitative analysis the difference in using NDVI, Ts and Ts/NDVI data sets to express information based on the indices (information entropy and averaged information grads), and evaluate the relative role of Ts/NDVI data set in the discrimination of different vegetation cover categories through comparison to traditional NDVI data set. 展开更多
关键词 vegetation index land surface temperature NDVI-Ts space information entropy
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NEW METHOD FOR MEASURING FUZZINESS IN ROUGH SETS 被引量:4
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作者 何亚群 胡寿松 魏崇辉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期31-35,共5页
A method with the fuzzy entropy for measuring fuzziness to fuzzy problem in rough sets is proposed. A new sort of the fuzzy entropy is given. The calculating formula and the equivalent expression method with the fuzzy... A method with the fuzzy entropy for measuring fuzziness to fuzzy problem in rough sets is proposed. A new sort of the fuzzy entropy is given. The calculating formula and the equivalent expression method with the fuzzy entropy in rough sets based on equivalence relation are provided, and the properties of the fuzzy entropy are proved. The fuzzy entropy based on equivalent relation is extended to generalize the fuzzy entropy based on general binary relation, and the calculating formula and the equivalent expression of the generalized fuzzy entropy are also given. Finally, an example illustrates the way for getting the fuzzy entropy. Results show that the fuzzy entropy can conveniently measure the fuzziness in rough sets. 展开更多
关键词 rough sets FUZZINESS fuzzy entropy generalized fuzzy entropy
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Two-Dimensional Entropy Method Based on Genetic Algorithm 被引量:4
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作者 王蕾 沈庭芝 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期184-188,共5页
Two dimensional(2 D) entropy method has to pay the price of time when applied to image segmentation. So the genetic algorithm is introduced to improve the computational efficiency of the 2 D entropy method. The pro... Two dimensional(2 D) entropy method has to pay the price of time when applied to image segmentation. So the genetic algorithm is introduced to improve the computational efficiency of the 2 D entropy method. The proposed method uses both the gray value of a pixel and the local average gray value of an image. At the same time, the simple genetic algorithm is improved by using better reproduction and crossover operators. Thus the proposed method makes up the 2 D entropy method’s drawback of being time consuming, and yields satisfactory segmentation results. Experimental results show that the proposed method can save computational time when it provides good quality segmentation. 展开更多
关键词 THRESHOLDING image segmentation entropy method genetic algorithm
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Computer vision technology in log volume inspection 被引量:3
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作者 汪亚明 黄文清 赵匀 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期67-70,84,共4页
Log volume inspection is very important in forestry research and paper making engineering. This paper proposed a novel approach based on computer vision technology to cope with log volume inspection. The needed hardwa... Log volume inspection is very important in forestry research and paper making engineering. This paper proposed a novel approach based on computer vision technology to cope with log volume inspection. The needed hardware system was analyzed and the details of the inspection algorithms were given. A fuzzy entropy based on image enhancement algorithm was presented for enhancing the image of the cross-section of log. In many practical applications the cross-section is often partially invisible, and this is the major obstacle for correct inspection. To solve this problem, a robust Hausdorff distance method was proposed to recover the whole cross-section. Experiment results showed that this method was efficient. 展开更多
关键词 Log volume Automatic inspection Computer vision Fuzzy entropy Hausdorff distance
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AUTOMATIC MULTILEVEL THRESHOLDING METHOD BASED ON MAXIMUM ENTROPY 被引量:2
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作者 曹力 史忠科 郑家伟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第4期335-338,共4页
In the multilevel thresholding segmentation of the image, the classification number is always given by the supervisor. To solve this problem, a fast multilevel thresholding algorithm considering both the threshold val... In the multilevel thresholding segmentation of the image, the classification number is always given by the supervisor. To solve this problem, a fast multilevel thresholding algorithm considering both the threshold value and the classification number is proposed based on the maximum entropy, and the self-adaptive criterion of the classification number is given. The algorithm can obtain thresholds and automatically decide the classification number. Experimental results show that the algorithm is effective. 展开更多
关键词 multilevel thresholding maximum entropy classification number nonparametric method
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AN ALGORITHM OF EDGE DETECTION BASED ON ENTROPY OPERATOR 被引量:3
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作者 王晖 张基宏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期21-25,共5页
This paper presents an algorithm of edge detection in image processing. A new entropy operator and threshold estimation technique are effectively proposed. The algorithm overcomes some drawbacks of Shiozaki operator. ... This paper presents an algorithm of edge detection in image processing. A new entropy operator and threshold estimation technique are effectively proposed. The algorithm overcomes some drawbacks of Shiozaki operator. It not only has higher speed but also can extract the edge better. Finally, an example of 2D image is given to demonstrate the usefulness and advantages of the algorithm. 展开更多
关键词 image processing edge detection entropy operator
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A New Adaptive Image Segmentation Method 被引量:2
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作者 沈庭芝 方子文 +1 位作者 吴玲艳 王飞 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期316-321,共6页
Aim Researching the optimal thieshold of image segmentation. M^ethods An adaptiveimages segmentation method based on the entropy of histogram of gray-level picture and genetic. algorithm (GA) was presental. Results ... Aim Researching the optimal thieshold of image segmentation. M^ethods An adaptiveimages segmentation method based on the entropy of histogram of gray-level picture and genetic. algorithm (GA) was presental. Results In our approach, the segmentation problem was formulated as an optimization problem and the fitness of GA which can efficiently search the segmentation parameter space was regarded as the quality criterion. Conclusion The methodcan be adapted for optimal behold segmentation. 展开更多
关键词 genetic algorithm image segmentation entropy of histogram segmenting threshold
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Adaptive genetic algorithm with the criterion of premature convergence 被引量:9
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作者 袁晓辉 曹玲 夏良正 《Journal of Southeast University(English Edition)》 EI CAS 2003年第1期40-43,共4页
To counter the defect of traditional genetic algorithms, an improved adaptivegenetic algorithm with the criterion of premature convergence is provided. The occurrence ofpremature convergence is forecasted using colony... To counter the defect of traditional genetic algorithms, an improved adaptivegenetic algorithm with the criterion of premature convergence is provided. The occurrence ofpremature convergence is forecasted using colony entropy and colony variance. When prematureconvergence occurs, new individuals are generated in proper scale randomly based on superiorindividuals in the colony. We use these new individuals to replace some individuals in the oldcolony. The updated individuals account for 30 percent - 40 percent of all individuals and the sizeof scale is related to the distribution of the extreme value of the target function. Simulationtests show that there is much improvement in the speed of convergence and the probability of globalconvergence. 展开更多
关键词 genetic algorithm premature convergence ADAPTATION
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A Robust Low Power Chaos-Based Truly Random Number Generator 被引量:1
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作者 周童 周志波 +1 位作者 喻明艳 叶以正 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第1期69-74,共6页
This paper presents a low power,truly random number generator (TRNG) based on a simple chaotic map of the Bernoulli shift,which is extended to remain robustness in implementation. The map is realized by switched-cur... This paper presents a low power,truly random number generator (TRNG) based on a simple chaotic map of the Bernoulli shift,which is extended to remain robustness in implementation. The map is realized by switched-current techniques that can fully integrate it in a cryptosystem on a chip. A pipelined architecture post-processed by a simple XOR circuit is used to improve the entropy. The TRNG is fabricated in an HJTC 0.18μm CMOS mixed signal process,and the statistical properties are investigated by measurement results. The power consumption is only 1.42mW and the truly random output bit rate is 10Mbit/s. 展开更多
关键词 random number generator CHAOS ENTROPY switched current
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Application of combination weighting method in contract risk's evaluation of third party logistics 被引量:3
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作者 傅新平 邹敏 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期128-132,共5页
First,the analytical hierarchy process(AHP),which stands for the subjective weighting method,and the entropy method,which stands for the objective weighting method,are chosen to calculate the index weights of the cont... First,the analytical hierarchy process(AHP),which stands for the subjective weighting method,and the entropy method,which stands for the objective weighting method,are chosen to calculate the index weights of the contract risks of third party logistics(TPL),respectively.Then,they can determine the combination weights using the combination weighting method.Second,using the combination weights,the contract risks of TPL are evaluated through the fuzzy comprehensive evaluation method.According to the combination weights,the most important risk factor of the contract risks of TPL is choosing sub-contractors.The results are basically consistent with the facts and show that the weights determined by the combination weighting method can avoid the man-made deviations of the subjective weighting method on the one hand,and prevent results opposite to the reality brought about by the objective weighting method on the other hand.Meanwhile,the results of the fuzzy comprehensive evaluation are that the contract risks of TPL are at a high risk level.Roughly this matches real situations,and it indicates that the combination weighting method can generate the comprehensive assessment more scientifically and more reasonably as well. 展开更多
关键词 analytical hierarchy process(AHP) entropy method combination weighting method contract risk
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