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基于Z-number-IBWM-TODIM的应急供应商评估与选择研究
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作者 谢培成 倪静 《物流科技》 2024年第8期1-4,13,共5页
文章针对应急供应商选择过程中评价信息的不完全可靠性及专家背景的多样性问题,提出了一种基于Z-number和IBWM-TODIM方法相结合的评估框架,以此来选择应急供应商。该方法利用Z-number同时描述认知信息的不确定性和可靠性,增强了决策结... 文章针对应急供应商选择过程中评价信息的不完全可靠性及专家背景的多样性问题,提出了一种基于Z-number和IBWM-TODIM方法相结合的评估框架,以此来选择应急供应商。该方法利用Z-number同时描述认知信息的不确定性和可靠性,增强了决策结果的可靠性和合理性;使用解释结构模型ISM确定最优指标和最劣指标,降低BWM方法的主观性,得到了指标权重;通过群体一致性和Z-number中的可靠性信息确定专家权重,使用TODIM方法进行排序,为应急供应商选择提供了更为准确和可靠的决策依据。 展开更多
关键词 应急供应商评估 Z-number ISM 最优最劣法 TODIM
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基于融合WM算法的Mamdani型模糊推理的板桥损伤定量分析
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作者 项长生 王旭 +2 位作者 赵华 狄生奎 王立宪 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第8期173-180,共8页
为对板桥局部位置的损伤程度进行定量分析,提出1种基于融合WM算法的Mamdani型模糊推理板桥损伤定量分析方法,探讨影响面指标和损伤程度之间的独特联系,并通过MIDAS及Python模拟计算并分析板的损伤程度。研究结果表明:模糊逻辑系统具有... 为对板桥局部位置的损伤程度进行定量分析,提出1种基于融合WM算法的Mamdani型模糊推理板桥损伤定量分析方法,探讨影响面指标和损伤程度之间的独特联系,并通过MIDAS及Python模拟计算并分析板的损伤程度。研究结果表明:模糊逻辑系统具有较为出色的记忆能力。当融合WM算法到模糊逻辑系统中时,不论是单点损伤还是多点损伤,都能对板桥的损伤程度进行准确识别;当未融合WM算法时,由于其模糊规则没有进行置信度计算,将错误的规则也计算在内,最终导致定量结果精度下降。研究结果可为板桥结构的损伤评估和维护策略提供较为科学准确的参考。 展开更多
关键词 板桥 模糊逻辑 wm算法 损伤识别 影响面
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Genome-wide investigation to assess copy number variants in the Italian local chicken population 被引量:1
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作者 Filippo Cendron Martino Cassandro Mauro Penasa 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期563-577,共15页
Background Copy number variants(CNV)hold significant functional and evolutionary importance.Numerous ongoing CNV studies aim to elucidate the etiology of human diseases and gain insights into the population structure ... Background Copy number variants(CNV)hold significant functional and evolutionary importance.Numerous ongoing CNV studies aim to elucidate the etiology of human diseases and gain insights into the population structure of livestock.High-density chips have enabled the detection of CNV with increased resolution,leading to the identification of even small CNV.This study aimed to identify CNV in local Italian chicken breeds and investigate their distribution across the genome.Results Copy number variants were mainly distributed across the first six chromosomes and primarily associated with loss type CNV.The majority of CNV in the investigated breeds were of types 0 and 1,and the minimum length of CNV was significantly larger than that reported in previous studies.Interestingly,a high proportion of the length of chromosome 16 was covered by copy number variation regions(CNVR),with the major histocompatibility complex being the likely cause.Among the genes identified within CNVR,only those present in at least five animals across breeds(n=95)were discussed to reduce the focus on redundant CNV.Some of these genes have been associated to functional traits in chickens.Notably,several CNVR on different chromosomes harbor genes related to muscle development,tissue-specific biological processes,heat stress resistance,and immune response.Quantitative trait loci(QTL)were also analyzed to investigate potential overlapping with the identified CNVR:54 out of the 95 gene-containing regions overlapped with 428 QTL associated to body weight and size,carcass characteristics,egg production,egg components,fat deposition,and feed intake.Conclusions The genomic phenomena reported in this study that can cause changes in the distribution of CNV within the genome over time and the comparison of these differences in CNVR of the local chicken breeds could help in preserving these genetic resources. 展开更多
关键词 CHICKEN Copy number variant CONSERVATION Local breed SNP
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混合级联H桥逆变器的新型SHEPWM功率均衡控制策略
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作者 顾军 丁超 +2 位作者 卜荣荣 蔡润哲 王伟健 《电机与控制学报》 EI CSCD 北大核心 2024年第7期178-186,共9页
对于直流侧电压比为1∶1∶2的混合级联H桥逆变器,传统的指定谐波消除脉宽调制法(SHEPWM)存在各单元间输出功率不均衡问题,因此,提出一种双层功率均衡调制策略。首先,通过对消谐方程组中的基波幅值方程表达式进行等效拆分,使2个低压H桥... 对于直流侧电压比为1∶1∶2的混合级联H桥逆变器,传统的指定谐波消除脉宽调制法(SHEPWM)存在各单元间输出功率不均衡问题,因此,提出一种双层功率均衡调制策略。首先,通过对消谐方程组中的基波幅值方程表达式进行等效拆分,使2个低压H桥单元的输出电压基波幅值之和与高压H桥单元的输出电压基波幅值相等,实现了高低压H桥单元间的功率均衡,即外层功率均衡。其次,利用逻辑运算的方法对低压单元的初始驱动信号进行逻辑重组,实现2个低压单元间的功率均衡,即内层功率均衡;然后使用改进的实数型遗传算法(IRCGA-2)求出消谐方程组的解,消除指定的谐波,得到高质量的输出电压。最后,通过仿真和实验证明了调制策略的正确性与有效性。 展开更多
关键词 混合级联H桥逆变器 指定谐波消除 双层功率均衡 基波幅值 逻辑运算 改进的实数型遗传算法
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The first factor affecting dryland winter wheat grain yield under various mulching measures: Spike number 被引量:1
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作者 Yingxia Dou Hubing Zhao +4 位作者 Huimin Yang Tao Wang Guanfei Liu Zhaohui Wang Sukhdev Malhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期836-848,共13页
Water is the key factor limiting dryland wheat grain yield.Mulching affects crop yield and yield components by affecting soil moisture.Further research is needed to determine the relationships between yield components... Water is the key factor limiting dryland wheat grain yield.Mulching affects crop yield and yield components by affecting soil moisture.Further research is needed to determine the relationships between yield components and soil moisture with yield,and to identify the most important factor affecting grain yield under various mulching measures.A long-term 9-yearifeld experiment in the Loess Plateau of Northwest China was carried out with three treatments:no mulch (CK),plastic mulch (M_(P)) and straw mulch (M_(S)).Yield factors and soil moisture were measured,and the relationships between them were explored by correlation analysis,structural equation modeling and significance analysis.The results showed that compared with CK,the average grain yields of M_(P) and M_(S) increased by 13.0and 10.6%,respectively.The average annual grain yield of the M_(P) treatment was 134 kg ha^(–1) higher than the M_(S) treatment.There were no significant differences in yield components among the three treatments (P<0.05).Soil water storage of the M_(S) treatment was greater than the M_(P) treatment,although the differences were not statistically signifiant.Soil water storage during the summer fallow period (SWSSF) and soil water storage before sowing (SWSS) of M_(S) were significantly higher than in CK,which increased by 38.5 and 13.6%,respectively.The relationship between M_(P) and CK was not statistically significant for SWSSF,but the SWSS in M_(P) was significantly higher than in CK.In terms of soil water storage after harvest (SWSH) and water consumption in the growth period(ET),there were no signi?cant differences among the three treatments.Based on the three analysis methods,we found that spike number and ET were positively correlated with grain yield.However,the relative importance of spike number to yield was the greatest in the M_(P )and M_(S) treatments,while that of ET was the greatest in CK.Suifcient SWSSF could indirectly increase spike number and ET in the three treatments.Based on these results,mulch can improve yield and soil water storage.The most important factor affecting the grain yield of dryland wheat was spike number under mulching,and ET with CK.These findings may help us to understand the main factors influencing dryland wheat grain yield under mulching conditions compared to CK. 展开更多
关键词 dryland winter wheat plastic mulch spike number straw mulch
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Origin of Sexy Prime Numbers, Origin of Cousin Prime Numbers, Equations from Supposedly Prime Numbers, Origin of the Mersenne Number, Origin of the Fermat Number
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作者 Mady Ndiaye 《Advances in Pure Mathematics》 2024年第5期321-332,共12页
We have found through calculations that the differences between the closest supposed prime numbers other than 2 and 3 defined in the articles are: 2;4: and 6. For those whose difference is equal to 6, we showed their ... We have found through calculations that the differences between the closest supposed prime numbers other than 2 and 3 defined in the articles are: 2;4: and 6. For those whose difference is equal to 6, we showed their origin then we classified them into two categories according to their classes, we showed in which context two prime numbers which differ from 6 are called sexy and in what context they are said real sexy prime. For those whose difference is equal to 4, we showed their origin then we showed that two prime numbers which differ from 4, that is to say two cousin prime numbers, are successive. We made an observation on the supposed prime numbers then we established two pairs of equations from this observation and deduced the origin of the Mersenne number and that of the Fermat number. 展开更多
关键词 Cousin Prime numbers Sexy Prime numbers Real Sexy Prime numbers Equations from Supposed Prime numbers Mersenne number Fermat number Supposed Prime numbers Prime numbers
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The prediction of donor number and acceptor number of electrolyte solvent molecules based on machine learning
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作者 Huaping Hu Yuqing Shan +3 位作者 Qiming Zhao Jinglun Wang Lingjun Wu Wanqiang Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期374-382,共9页
Electrolyte solvents have a critical impact on the design of high performance and safe batteries.Gutmann's donor number(DN) and acceptor number(AN) values are two important parameters to screen and design superior... Electrolyte solvents have a critical impact on the design of high performance and safe batteries.Gutmann's donor number(DN) and acceptor number(AN) values are two important parameters to screen and design superior electrolyte solvents. However, it is more time-consuming and expensive to obtain DN and AN values through experimental measurements. Therefore, it is essential to develop a method to predict DN and AN values. This paper presented the prediction models for DN and AN based on molecular structure descriptors of solvents, using four machine learning algorithms such as Cat Boost(Categorical Boosting), GBRT(Gradient Boosting Regression Tree), RF(Random Forest) and RR(Ridge Regression).The results showed that the DN and AN prediction models based on Cat Boost algorithm possesses satisfactory prediction ability, with R^(2) values of the testing set are 0.860 and 0.96. Moreover, the study analyzed the molecular structure parameters that impact DN and AN. The results indicated that TDB02m(3D Topological distance based descriptors-lag 2 weighted by mass) had a significant effect on DN, while HATS1s(leverage-weighted autocorrelation of lag 1/weighted by I-state) plays an important role in AN. The work provided an efficient approach for accurately predicting DN and AN values, which is useful for screening and designing electrolyte solvents. 展开更多
关键词 Machine learning Donor number Acceptor number Electrolyte solvents
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Preliminary Identification of a Prime Number Other Than 2 and 3, the Origin of Twin Prime Numbers, the Structure of the Chain of Prime Numbers and the Set of Prime Numbers Less Than a Given Integer
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作者 Mady Ndiaye 《Advances in Pure Mathematics》 2024年第1期30-48,共19页
The application of the Euclidean division theorem for the positive integers allowed us to establish a set which contains all the prime numbers and this set we called it set of supposedly prime numbers and we noted it ... The application of the Euclidean division theorem for the positive integers allowed us to establish a set which contains all the prime numbers and this set we called it set of supposedly prime numbers and we noted it E<sub>sp</sub>. We subsequently established from the previous set the set of non-prime numbers (the set of numbers belonging to this set and which are not prime) denoted E<sub>np</sub>. We then extracted from the set of supposedly prime numbers the numbers which are not prime and the set of remaining number constitutes the set of prime numbers denoted E<sub>p</sub>. We have deduced from the previous set, the set of prime numbers between two natural numbers. We have explained during our demonstrations the origin of the twin prime numbers and the structure of the chain of prime numbers. 展开更多
关键词 Supposedly Prime numbers Non-Prime numbers Prime numbers Prime numbers Less Than a Given Integer Prime numbers between Two Given Integers
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On the Number of Primes in the Interval (x, 2x) by an Elementary Method
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作者 Sudhindra B. Kittur 《Advances in Pure Mathematics》 2024年第1期16-29,共14页
An elementary formula to know the number of primes in the interval (x, 2x) close to the exact figure for a fixed x is given here. A new elementary equation is derived (a relation between prime numbers and composite nu... An elementary formula to know the number of primes in the interval (x, 2x) close to the exact figure for a fixed x is given here. A new elementary equation is derived (a relation between prime numbers and composite numbers distributed in the interval [1, 2x]). An elementary method to know the number of primes in a given magnitude is suitably placed in the form of a general formula, and we have proved it. The general formula is applied to the terms of the equation, and a tactical simplification of the terms gives rise to an expression whose verification envisages scope for its further studies. 展开更多
关键词 Prime numbers Composite numbers EXPRESSION INTEGERS
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A novel Effective Panicle Number per Plant 4 haplotype enhances grain yield by coordinating panicle number and grain number in rice
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作者 Yun Wang Xiaoqian Wang +6 位作者 Laiyuan Zhai Sundus Zafar Congcong Shen Shuangbing Zhu Kai Chen Yun Wang Jianlong Xu 《The Crop Journal》 SCIE CSCD 2024年第1期202-212,共11页
Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-... Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-wide association analysis to identify the EPN4 gene,which is allelic to NARROW LEAF1(NAL1).Overexpression lines containing the Teqing allele(TQ)of EPN4 had significantly increased EPN.NIL-EPN4^(TQ) in japonica(geng)cultivar Lemont(LT)exhibited significantly improved EPN but decreased grain number and flag leaf size relative to LT.Haplotype analysis indicated that accessions with EPN4-1 had medium EPN,medium grain number,and medium grain weight,but had the highest grain yield among seven haplotypes,indicating that EPN4-1 is an elite haplotype of EPN4 for positive coordination of the three components of grain yield.Furthermore,accessions carrying the combination of EPN4-1 and haplotype GNP1-6 of GNP1 for grain number per panicle showed higher grain yield than those with other allele combinations.Therefore,pyramiding of EPN4-1 and GNP1-6 could be a preferred approach to obtain high yield potential in breeding. 展开更多
关键词 RICE Effective panicle number per plant Grain number per panicle HAPLOTYPE Grain yield potential
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How Prime Numbers Are Interconnected and Built with Two Equations: Addition and Subtraction Rules the Function (6µ)
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作者 John Richard Wisdom 《Advances in Pure Mathematics》 2024年第4期228-241,共14页
Are all prime numbers linked by four simple functions? Can we predict when a prime will appear in a sequence of primes? If we classify primes into two groups, Group 1 for all primes that appear before ζ (such that , ... Are all prime numbers linked by four simple functions? Can we predict when a prime will appear in a sequence of primes? If we classify primes into two groups, Group 1 for all primes that appear before ζ (such that , for instance 5, ), an even number divisible by 3 and 2, and Group 2 for all primes that are after ζ (such that , for instance 7), then we find a simple function: for each prime in each group, , where n is any natural number. If we start a sequence of primes with 5 for Group 1 and 7 for Group 2, we can attribute a μ value for each prime. The μ value can be attributed to every prime greater than 7. Thus for Group 1, and . Using this formula, all the primes appear for , where μ is any natural number. 展开更多
关键词 number Theory Prime number Groups Twin Primes Prime Structure and Sequence Prime Subtraction and Addition
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基于决策者偏好构造的概率语言型Z-number多属性决策方法 被引量:1
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作者 王旭婷 毛军军 张新宇 《海南师范大学学报(自然科学版)》 CAS 2024年第2期135-143,共9页
由于决策环境的日益复杂,专家评价信息往往会包含专家偏好,因此有必要对专家偏好进行识别与处理。针对这一情况,提出了基于决策者偏好构造的概率语言型Z-number并应用于多属性决策问题中。首先,针对专家偏好未知的情况,提出了一种基于... 由于决策环境的日益复杂,专家评价信息往往会包含专家偏好,因此有必要对专家偏好进行识别与处理。针对这一情况,提出了基于决策者偏好构造的概率语言型Z-number并应用于多属性决策问题中。首先,针对专家偏好未知的情况,提出了一种基于修正的平均得分距离,由专家评价信息确定专家偏好。然后,依据得到的专家偏好,利用GOWPA算子与最大熵生成概率语言型Z-number。同时,获得专家评价信息的可信度,由专家可信度聚合专家信息并采用TODIM方法对方案进行排序。最后,在国家大力提倡节能减排的背景下,将所提方法应用于国家绿色矿山试点企业的选取上,验证了所提方法的有效性和可行性。 展开更多
关键词 概率语言型Z-number 偏好 GOWPA算子 最大熵 多准则群决策
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The wheat sucrose synthase gene TaSus1 is a determinant of grain number per spike
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作者 Liping Shen Lili Zhang +20 位作者 Changbin Yin Xiaowan Xu Yangyang Liu Kuocheng Shen He Wu Zhiwen Sun Ke Wang Zhonghu He Xueyong Zhang Chenyang Hao Jian Hou Aoyue Bi Xuebo Zhao Daxing Xu Botao Ye Xuchang Yu Ziying Wang Danni Liu Yuanfeng Hao Fei Lu Zifeng Guo 《The Crop Journal》 SCIE CSCD 2024年第1期295-300,共6页
Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The e... Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions. 展开更多
关键词 Domestication selection Fertile spikelet number per spike(FSN) Geographical differentiation Grain number per spike(GNS) TaSus1
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Ovule number as a rising star for regulating seed yield:Hope or hype
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作者 Shahid Ullah Khan Ahmad Ali +5 位作者 Sumbul Saeed Yonghai Fan Ali Shehazd Hameed Gul Shah Fahad Kun Lu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第11期3623-3640,共18页
Rapeseed(Brassica napus L.)is the second most widely grown premium oilseed crop globally,mainly for its vegetable oil and protein meal.One of the main goals of breeders is producing high-yield rapeseed cultivars with ... Rapeseed(Brassica napus L.)is the second most widely grown premium oilseed crop globally,mainly for its vegetable oil and protein meal.One of the main goals of breeders is producing high-yield rapeseed cultivars with sustainable production to meet the requirements of the fast-growing population.Besides the pod number,seeds per silique(SS),and thousand-seed weight(TSW),the ovule number(ON)is a decisive yield determining factor of individual plants and the final seed yield.In recent years,tremendous efforts have been made to dissect the genetic and molecular basis of these complex traits,but relatively few genes or loci controlling these traits have been reported thus far.This review highlights the updated information on the hormonal and molecular basis of ON and development in model plants(Arabidopsis thaliana).It also presents what is known about the hormonal,molecular,and genetic mechanism of ovule development and number,and bridges our understanding between the model plant species(A.thaliana)and cultivated species(B.napus).This report will open new pathways for primary and applied research in plant biology and benefit rapeseed breeding programs.This synopsis will stimulate research interest to further understand ovule number determination,its role in yield improvement,and its possible utilization in breeding programs. 展开更多
关键词 Brassica napus ovule number genetics ovule development hormonal signaling
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Lychrel Numbers in Base 10: A Probabilistic Approach
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作者 Rostand S. Kuitché 《Advances in Pure Mathematics》 2024年第8期667-694,共28页
For decades, Lychrel numbers have been studied on many bases. Their existence has been proven in base 2, 11 or 17. This paper presents a probabilistic proof of the existence of Lychrel number in base 10 and provides s... For decades, Lychrel numbers have been studied on many bases. Their existence has been proven in base 2, 11 or 17. This paper presents a probabilistic proof of the existence of Lychrel number in base 10 and provides some properties which enable a mathematical extraction of new Lychrel numbers from existing ones. This probabilistic approach has the advantage of being extendable to other bases. The results show that palindromes can also be Lychrel numbers. 展开更多
关键词 Probabilistic Approach PALINDROMES Lychrel numbers Iteration Function DIGITS
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Study of baryon number transport dynamics and strangeness conservation effects using Ω-hadron correlations
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作者 Wei-Jie Dong Xiao-Zhou Yu +4 位作者 Si-Yuan Ping Xia-Tong Wu Gang Wang Huan-Zhong Huang Zi-Wei Lin 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期147-156,共10页
In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been tr... In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been transported from the incident nuclei and/or produced in the baryon-pair production of Ω with other types of anti-hyperons such as Ξ. To investigate these two scenarios, we propose to measure the correlations between Ω and K and between Ω and anti-hyperons. We use two versions, the default and string-melting, of a multiphase transport(AMPT) model to illustrate the method for measuring the correlation and to demonstrate the general shape of the correlation. We present the Ω-hadron correlations from simulated Au+Au collisions at ■ =7.7 and 14.6 Ge V and discuss the dependence on the collision energy and on the hadronization scheme in these two AMPT versions. These correlations can be used to explore the mechanism of baryon number transport and the effects of baryon number and strangeness conservation on nuclear collisions. 展开更多
关键词 Baryon number transport Strangeness conversation Correlation Gluon junction
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On Perron’s Formula and the Prime Numbers
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作者 Michael M. Anthony 《Advances in Pure Mathematics》 2024年第6期487-494,共8页
The Riemann hypothesis is intimately connected to the counting functions for the primes. In particular, Perron’s explicit formula relates the prime counting function to fixed points of iterations of the explicit form... The Riemann hypothesis is intimately connected to the counting functions for the primes. In particular, Perron’s explicit formula relates the prime counting function to fixed points of iterations of the explicit formula with particular relations involving the trivial and non-trivial roots of the Riemann Zeta function and the Primes. The aim of the paper is to demonstrate this relation at the fixed points of iterations of explicit formula, defined by functions of the form limT∈Ν→∞fT(zw)=zw,where, zwis a real number. 展开更多
关键词 Perron Fixed Points ITERATIONS number Theory Riemann Hypothesis ITERATIONS INVARIANCE PRIMES
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Impacts of Aggregation Methods and Trophospecies Number on the Structure and Function of Marine Food Webs
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作者 LI Pengcheng ZHANG Chongliang +4 位作者 XU Binduo JI Yupeng LI Fan REN Yiping XUE Ying 《Journal of Ocean University of China》 CAS CSCD 2024年第1期190-198,共9页
Aggregation of species with similar ecological properties is one of the effective methods to simplify food web researches.However,species aggregation will affect not only the complexity of modeling process but also th... Aggregation of species with similar ecological properties is one of the effective methods to simplify food web researches.However,species aggregation will affect not only the complexity of modeling process but also the accuracy of models’outputs.Selection of aggregation methods and the number of trophospecies are the keys to study the simplification of food web.In this study,three aggregation methods,including taxonomic aggregation(TA),structural equivalence aggregation(SEA),and self-organizing maps(SOM),were analyzed and compared with the linear inverse model–Markov Chain Monte Carlo(LIM-MCMC)model.Impacts of aggregation methods and trophospecies number on food webs were evaluated based on the robustness and unitless of ecological net-work indices.Results showed that aggregation method of SEA performed better than the other two methods in estimating food web structure and function indices.The effects of aggregation methods were driven by the differences in species aggregation principles,which will alter food web structure and function through the redistribution of energy flow.According to the results of mean absolute percentage error(MAPE)which can be applied to evaluate the accuracy of the model,we found that MAPE in food web indices will increase with the reducing trophospecies number,and MAPE in food web function indices were smaller and more stable than those in food web structure indices.Therefore,trade-off between simplifying food webs and reflecting the status of ecosystem should be con-sidered in food web studies.These findings highlight the importance of aggregation methods and trophospecies number in the analy-sis of food web simplification.This study provided a framework to explore the extent to which food web models are affected by dif-ferent species aggregation,and will provide scientific basis for the construction of food webs. 展开更多
关键词 LIM-MCMC model species aggregation trophospecies number aggregation methods food web indices
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Three- and Four-Dimensional Generalized Pythagorean Numbers
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2024年第1期1-15,共15页
The Pythagorean triples (a, b | c) of planar geometry which satisfy the equation a<sup>2</sup>+b<sup>2</sup>=c<sup>2</sup> with integers (a, b, c) are generalized to 3D-Pythagorean ... The Pythagorean triples (a, b | c) of planar geometry which satisfy the equation a<sup>2</sup>+b<sup>2</sup>=c<sup>2</sup> with integers (a, b, c) are generalized to 3D-Pythagorean quadruples (a, b, c | d) of spatial geometry which satisfy the equation a<sup>2</sup>+b<sup>2</sup>+c<sup>2</sup>=d<sup>2</sup> with integers (a, b, c, d). Rules for a parametrization of the numbers (a, b, c, d) are derived and a list of all possible nonequivalent cases without common divisors up to d<sup>2</sup> is established. The 3D-Pythagorean quadruples are then generalized to 4D-Pythagorean quintuples (a, b, c, d | e) which satisfy the equation a<sup>2</sup>+b<sup>2</sup>+c<sup>2</sup>+d<sup>2</sup>=e<sup>2</sup> and a parametrization is derived. Relations to the 4-square identity are discussed which leads also to the N-dimensional case. The initial 3D- and 4D-Pythagorean numbers are explicitly calculated up to d<sup>2</sup>, respectively, e<sup>2</sup>. 展开更多
关键词 number Theory Pythagorean Triples Tesseract 4-Square Identity Diophantine Equation
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Novel Rifle Number Recognition Based on Improved YOLO in Military Environment
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作者 Hyun Kwon Sanghyun Lee 《Computers, Materials & Continua》 SCIE EI 2024年第1期249-263,共15页
Deep neural networks perform well in image recognition,object recognition,pattern analysis,and speech recog-nition.In military applications,deep neural networks can detect equipment and recognize objects.In military e... Deep neural networks perform well in image recognition,object recognition,pattern analysis,and speech recog-nition.In military applications,deep neural networks can detect equipment and recognize objects.In military equipment,it is necessary to detect and recognize rifle management,which is an important piece of equipment,using deep neural networks.There have been no previous studies on the detection of real rifle numbers using real rifle image datasets.In this study,we propose a method for detecting and recognizing rifle numbers when rifle image data are insufficient.The proposed method was designed to improve the recognition rate of a specific dataset using data fusion and transfer learningmethods.In the proposed method,real rifle images and existing digit images are fusedas trainingdata,andthe final layer is transferredto theYolov5 algorithmmodel.The detectionand recognition performance of rifle numbers was improved and analyzed using rifle image and numerical datasets.We used actual rifle image data(K-2 rifle)and numeric image datasets,as an experimental environment.TensorFlow was used as the machine learning library.Experimental results show that the proposed method maintains 84.42% accuracy,73.54% precision,81.81% recall,and 77.46% F1-score in detecting and recognizing rifle numbers.The proposed method is effective in detecting rifle numbers. 展开更多
关键词 Machine learning deep neural network rifle number recognition DETECTION
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