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Agro-Morphological Variability in Eight Bambara Groundnut (Vigna subterranea (L.) Verdc.) Morphotypes from Zinder (Niger)
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作者 Oumarou Zango Rabiou Abdou +2 位作者 Saley Adamou Salamatou Agbo So Timothée Kouassi Bakasso Yacoubou 《Agricultural Sciences》 CAS 2023年第1期1-10,共10页
Bambara groundnut (Vigna subterranea (L.) Verdc.) has economic importance for the producers and the traders as cash crop since it generates substantial income for households in Niger. The objective of this study was t... Bambara groundnut (Vigna subterranea (L.) Verdc.) has economic importance for the producers and the traders as cash crop since it generates substantial income for households in Niger. The objective of this study was to assess eight (8) Bambara groundnut morphotype from Université André Salifou de Zinder in Niger Republic by their morphological and agronomic characters. The experiment was conducted in a randomized complete block design with three replications during the rainy season of 2020-2021. Data were collected on the Number of leaves, Plant height (cm), Growth habit (cm), Terminal leaflet length, Terminal leaflet width, Number of nodes/stem, Number of stems/plant, Number of pods/plant, Weight of 100 pods (g), Weight of 100 seeds (g), Length of seeds (mm), Width of seeds (mm), Weight of seeds/Plot (kg). There were significant differences for all characters, except Number of leaves, Terminal leaflet length, Terminal leaflet width, Length of seeds (mm) Weight of 100 pods (g), Weight of 100 seeds (g). The morphotypes UZ-VZ-04, UZ-VZ-03, UZ-VZ-06, UZ-VZ-02 and UZ-VZ-05 have demonstrated good performance for grain weight per plot and can be useful for a breeding program. 展开更多
关键词 Vigna subterranea ACCESSIONS agro-morphological Traits Weight of 100 Seeds
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Strong Laws of Large Numbers for Sequences of Blockwise m-Dependent and Sub-Orthogonal Random Variables under Sublinear Expectations
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作者 Jialiang FU 《Journal of Mathematical Research with Applications》 2026年第1期103-118,共16页
In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random vari... In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random variables,and another is for sub-orthogonal random variables.Both extend the strong law of large numbers for independent random variables under sublinear expectations to the non-independent case. 展开更多
关键词 sublinear expectations strong law of large numbers blockwise m-dependent suborthogonal random variables
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Agro-Morphological Characterization of a Collection of Fonio [Digitaria exilis (Kippist.) Stapf.] Accessions from Burkina Faso
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作者 Balma Patrice Kabore Boukare +3 位作者 Kiebre Mariam Kiebre Zakaria Sanou Jacob Bationo/Kando Pauline 《American Journal of Plant Sciences》 2023年第6期677-690,共14页
Considered as the oldest cereal, fonio (Digitaria exilis Stapf.) is grown in West Africa for its therapeutic virtues, its nutritional and organoleptic qualities. It plays an important socio-cultural and economic role ... Considered as the oldest cereal, fonio (Digitaria exilis Stapf.) is grown in West Africa for its therapeutic virtues, its nutritional and organoleptic qualities. It plays an important socio-cultural and economic role for the populations of western Burkina Faso. However, very few studies on the genetic diversity of fonio have been carried out. This study aims to contribute to a better knowledge of the diversity of Digitaria exilis in Burkina Faso using agro-morphological descriptors. Thus, 60 accessions of fonio collected from western Burkina Faso were characterized using 21 agro-morphological characters according to an Alpha Latice design with three replications. The study showed morphological variability for most of the qualitative and quantitative characters studied. Principal component analysis (PCA) explained 56.07% of the variability. Hierarchical cluster analysis splits the accessions of the collection into four clusters using seven characters. These characters can constitute basic criteria for differentiating fonio accessions in Burkina Faso. The accessions of Group II have a long cycle and high production of grain, while the accessions of Group IV have a short cycle and low production of grain. The groups identified can serve as a starting point for fonio breeding in Burkina Faso. 展开更多
关键词 Digitaria exilis agro-morphological variability ACCESSION Burkina Faso
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Screening of Sapindus germplasm resources in China based on agro-morphological traits 被引量:1
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作者 Jiming Liu Shiqi Liu +9 位作者 Yuanyuan Xu Caowen Sun Zhong Chen Xin Wang Lixian Wang Shilun Gao Guochun Zhao Qiuyang He Xuehuang Weng Liming Jia 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第1期203-216,共14页
Sapindus L.species are widely cultivated for biodiesel,biomedical,and biochemical raw materials in southern China.However,yields fuctuate widely due to the lack of high-yielding,high-quality,stable cultivars.Therefore... Sapindus L.species are widely cultivated for biodiesel,biomedical,and biochemical raw materials in southern China.However,yields fuctuate widely due to the lack of high-yielding,high-quality,stable cultivars.Therefore,the objectives of this study were to evaluate three species and one variety among 149 nationwide Sapindus species and screen for elite accessions which would serve as Sapindus breeding materials.Accessions were evaluated on 19 agro-morphological traits by correlation analysis and principal component analysis.These displayed substantial diversity and a broad range of economic traits.In particular,accessions of Sapindus mukorossi and Sapindus rarak had more variation in economic traits than Sapindus delavayi and Sapindus rarak var.velutinus.Increased saponin accumulation may be achieved at the cost of seed oil production.Thirty elite accessions for oil and saponin production,and for comprehensive utilization were screened and accessions no.80,110,and 112 had significant potential to produce high yields.These elite accessions will facilitate the identification of genetic determinants of valuable traits and the effective utilization of trait variability in Sapindus breeding. 展开更多
关键词 agro-morphological traits Germplasm resources Sapindus Principal component analysis
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Agro-Morphological Characterization of Cassava (Manihot esculenta Crantz) Cultivars from Chad 被引量:1
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作者 Djirabaye Nadjiam Papa Saliou Sarr +2 位作者 Michel Naïtormbaïdé Jean Marie Mbaïlao Mbaïguinam Aliou Guisse 《Agricultural Sciences》 2016年第7期479-492,共14页
Cassava is a considerable source of food and income for the rural community of the south of Chad. Despite the importance of the diversity of cultivars in situ, their morphological traits and agronomic performance are ... Cassava is a considerable source of food and income for the rural community of the south of Chad. Despite the importance of the diversity of cultivars in situ, their morphological traits and agronomic performance are under investigated. The aim of this study is to characterize and analyze the variability structure of the cassava’s germplasm. Fifty nine cultivars collected from five main cassava growing regions, were evaluated by forty five agro-morphological descriptors in a Fisher design replicated three times. Data were collected at three, six, nine and twelve months after planting. High phenotypic variability was shown within the collection for the color of apical leaf, vein leaf, petiole, roots and pulp. The same case was observed for the root peduncle, the shape of the central leaflet and the root, the cortex root thickness and the texture of root epidermis. Significant to highly significant differences were observed for all the quantitative traits. High variability were shown for the size of the leaf lobe, petiole length, plant height, root number and length, harvest index, above-ground biomass and fresh root weight. Positive correlations were found between the leaflet and leaf lobe number. Fresh root weight was also positively correlated to the root number, length and diameter. Principal component analysis (PCA) on quantitative variable revealed four groups with two of them containing performant cultivars: Group II with small root, high potential yield but less leaflet and leaf lobe and group III characterized by some cultivars with high productivity, more leaflet and leaf lobe, more and bigger roots. At regional level, significant differences were shown within cultivars which were discriminated in relation to their origin region by the number of the leaf lobes. The better cultivars and the interesting traits could be used to improve cassava production in Chad. 展开更多
关键词 variability TRAITS Cassava Cultivars LOCAL Improved CHAD
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Agro-Morphological Characterization and Genetic Dissection of Linseed(Linum usitatissimum L.)Genotypes 被引量:1
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作者 A.K.M.Golam Sarwar Md.Sabibul Haque +6 位作者 Md.Ekramul Haque Md.Amir Hossain Md.Golam Azam Md.Nesar Uddin Eldessoky S.Dessoky Mahmoud A.Basry Md.Alamgir Hossain 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第8期1721-1743,共23页
Linseed is a multipurpose crop and the crop needs further improvement to increase production and yield due to its high value and demand.This study aimed to assess the extent and pattern of genetic variability of forty... Linseed is a multipurpose crop and the crop needs further improvement to increase production and yield due to its high value and demand.This study aimed to assess the extent and pattern of genetic variability of forty linseed genotypes based on diverse agro–morphological and yield attributes.The field experiment was conducted following a Randomized Complete Block Design with three replications.Linseed germplasm showed a wide range of phenotypic expression,genetic variability and heritability for 30 studied traits.A low to high phenotypic coeffi-cient of variation(PCV)and genotypic coefficient of variation(GCV)were observed.The lowest genotypic(σ2 g)and phenotypic variances(σ2 p)were found in capsule diameter(CD),length of calyx(LC),capsule length(CL),seed length(SL),and seed breadth(SB).High broad-sense heritability(h2 b)with high genetic advance as a percentage of mean(GAM)were observed in days to germination started(DGS),days to 80%emergence(DE),plant height at 28 and 40 DAS,number of flowers(NFPP),filled capsules(NFCPP)and yield per plant(YPP)indicating additive gene action exists for these characters.Hierarchical cluster analysis separated 40 genotypes into five clusters,where Clusters I to V assembled with 13,4,4,5 and 14 genotypes,respectively.Considering yield and yield attributes,Cluster-IV(G3,G4,G6,G10 and G31)genotypes showed promising while,Cluster-II(G2,G16,G35,G36)and Cluster-III(G1,G33,G39 and G40)genotypes were dominant on plant morphological traits.Based on principal component analysis(PCA),few characters such as YPP,NFPP,NFCPP,days to first flowering and capsule formation,early emergence,days to branch initiation and plant heights at different growth stages revealed important and effective traits for consideration in the selection of linseed breeding programs. 展开更多
关键词 Genetic variability HERITABILITY genetic advance principal component analysis hierarchical clustering LINSEED
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Agro-Morphological, Physico-Chemical and Molecular Characterization of Rice Germplasm with Similar Names of Bangladesh
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作者 Mir Sharf Uddin AHMED Mohammad KHALEQUZZAMAN +1 位作者 Md.Khairul BASHAR Abul Kalam Mohammad SHAMSUDDIN 《Rice science》 SCIE CSCD 2016年第4期211-218,共8页
Thirty-one duplicate and similar named rice germplasms of Bangladesh were studied to assess the genetic variation for the agro-morphological and physico-chemical traits and simple sequence repeat banding patterns duri... Thirty-one duplicate and similar named rice germplasms of Bangladesh were studied to assess the genetic variation for the agro-morphological and physico-chemical traits and simple sequence repeat banding patterns during 2009–2012 at Bangladesh Rice Research Institute. The range of variations within the cultivar groups showed higher degree. The principal component analysis showed that the first five components with vector values > 1 contributed 82.90% of the total variations. The cluster analysis grouped the genotypes into four clusters, where no duplicate germplasm was found. The highest number(11) of genotypes was constellated in cluster I and the lowest(3) in cluster II. The intra- and inter-cluster distances were the maximum in cluster I(0.93) and between clusters I and IV(24.61), respectively, and the minimum in cluster IV(0.62) and between clusters I and III(5.07), respectively. The cluster mean revealed that the crosses between the genotypes of cluster I with those of clusters II and IV would exhibit high heterosis for maximum good characters. A total of 350 alleles varied from 3(RM277) to 14(RM21) with an average of 7.8 per locus were detected at 45 microsatellite loci across the 31 rice accessions. The gene diversity ranged from 0.48 to 0.90 with an average of 0.77, and the polymorphism information content values from 0.44(RM133) to 0.89(RM206) with an average of 0.74. RM206, RM21, RM55, RM258 and RM433 were considered as the best markers on the basis of their higher polymorphism information content values. The dendrogram from unweighted pair-group method with arithmetic average clustering also classified the genotypes into four groups, where group IV comprised of 20 genotypes and group III of one genotype, but no duplicate was found. Finally, similar and duplicate named rice germplasms need to be conserved in gene bank as are distinct from each other. 展开更多
关键词 diversity simple sequence repeat similar name LANDRACE rice agro-morphological and PHYSICO-CHEMICAL TRAIT
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Agro-morphological Characteristics and Sensory Evaluation of Native Peruvian Chili Peppers
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作者 Kirti Patel Rosa Calderon +3 位作者 Edgard Asencios Dioliza Vilchez Mavel Marcelo Rosario Rojas 《Journal of Agricultural Science and Technology(B)》 2016年第3期180-187,共8页
In this work, 31 native Peruvian chili peppers were evaluated for their agro-morphological characteristics and sensory attributes. The descriptive sensory analysis (DSA) was used to evaluate the 31 chili pepper samp... In this work, 31 native Peruvian chili peppers were evaluated for their agro-morphological characteristics and sensory attributes. The descriptive sensory analysis (DSA) was used to evaluate the 31 chili pepper samples based on their acid, bell pepper, sweet, tomato, apple, citrus, fruity, herbal, oregano and passion fruit attributes. The data obtained from the DSA enabled the grouping of these 31 chili peppers into six groups based on their different sensory attributes, such as fruity, bell pepper and herbal. The most abundant group (12 of the 31) had the bell pepper, apple, herbal, fruity and sweet attributes. Each group contained different species and different physical appearances, indicating that species or different forms of chili pepper do not define that sensory attribute. Considering the fact that Peruvian peppers are in high demand, the results achieved would be useful for growers, producers and chefs, as well as for further breeding activities. 展开更多
关键词 Chili peppers Peru sensory analysis agro-morphological characteristics.
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Preliminary Assessment of Genetic Diversity in Three Taro (Colocasia esculenta L, Schott) Landraces Using Agro-morphological and SSR DNA Characterisation
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作者 Tafadzwanashe Mabhaudhi Albert Thembinkosi Modi 《Journal of Agricultural Science and Technology(B)》 2013年第4期265-271,共7页
Taro (Colocasia esculenta L. Schott) is an important underutilised crop in South Africa, East Africa and Indonesia. Three taro landraces, namely, Dumbe Lomfula (wild), KwaNgwanase and Umbumbulu, were collected fro... Taro (Colocasia esculenta L. Schott) is an important underutilised crop in South Africa, East Africa and Indonesia. Three taro landraces, namely, Dumbe Lomfula (wild), KwaNgwanase and Umbumbulu, were collected from two locations in KwaZulu-Natal (KZN), South Africa, and planted at two locations, Pietermaritzburg (KZN) and Roodeplaat, Pretoria. Ago-morphological characterisation of vegetative and corm characteristics were done four months after planting and at harvest, respectively. Sampling for DNA fingerprinting using five SSR primers was done using leaf material four months after planting. Agro-morphological characterisation was useful in showing differences between the wild landrace and the two cultivated landraces, as well as identification of dasheen and eddoe types. SSR primer characterisation showed that despite significant morphological difference, the wild Dumbe Lomfula and Umbumbulu landraces were closely related but different from the KwaNgwanase landrace. Although landraces showed great morphological variation, this did not necessarily imply genetic variation. It is concluded that SSR primers are more useful for characterising taro landraces. 展开更多
关键词 agro-morphology characterisation DNA LANDRACES SSR primers taro (Colocasia esculenta L. Schott) geneticdiversity.
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Responses of Annual Variability of Vegetation NPP to Climate Variables Using Satellite Techniques in Gadarif State, Sudan
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作者 Anwar Mohamedelhassan Bo Zhang +1 位作者 Abdelrahim E. Jahelnabi Eman M. Elhassan 《Journal of Geographic Information System》 2024年第2期136-147,共12页
Plants play an essential role in matter and energy transformations and are key messengers in the carbon and energy cycle. Net primary productivity (NPP) reflects the capability of plants to transform solar energy into... Plants play an essential role in matter and energy transformations and are key messengers in the carbon and energy cycle. Net primary productivity (NPP) reflects the capability of plants to transform solar energy into photosynthesis. It is very sensible for factors affecting on vegetation variability such as climate, soils, plant characteristics and human activities. So, it can be used as an indicator of actual and potential trend of vegetation. In this study we used the actual NPP which was derived from MODIS to assess the response of NPP to climate variables in Gadarif State, from 2000 to 2010. The correlations between NPP and climate variables (temperature and precipitation) are calculated using Pearson’s Correlation Coefficient and ordinary least squares regression. The main results show the following 1) the correlation Coefficient between NPP and mean annual temperature is Somewhat negative for Feshaga, Rahd, Gadarif and Galabat areas and weakly negative in Faw area;2) the correlation Coefficient between NPP and annual total precipitation is weakly negative in Faw, Rahd and Galabat areas and somewhat negative in Galabat and Rahd areas. This study demonstrated that the correlation analysis between NPP and climate variables (precipitation and temperature) gives reliably result of NPP responses to climate variables that is clearly in a very large scale of study area. 展开更多
关键词 Climate Variables MODIS NPP Climate Change Correlation Coefficient Gadarif State Remote Sensing GIS Applications
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Genetic Diversity of Local Rice Accessions Cultivated in Guinea Based on Agro-Morphological Traits and Identification of Sources of Tolerance to Iron Toxicity
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作者 Mamadou Laho Barry Nerbéwendé Sawadogo +5 位作者 Mahamadi Hamed Ouédraogo Kiswendsida Romaric Nanema Sawa Camara Moussa Sié Pauline Bationo-Kando Mahamadou Sawadogo 《Agricultural Sciences》 2021年第10期1070-1088,共19页
In Guinea, traditional rice varieties are the most widely cultivated in rural areas despite their low yield and high susceptibility to iron toxicity. Moreover, the introduction of new improved varieties tolerant to ir... In Guinea, traditional rice varieties are the most widely cultivated in rural areas despite their low yield and high susceptibility to iron toxicity. Moreover, the introduction of new improved varieties tolerant to iron toxicity poses a serious threat to the preservation of the genetic resources of these traditional varieties, whose genetic diversity remains poorly known. The present study therefore aims at a better valorisation of these local rice cultivars through the evaluation of their agromorphological diversity and the identification of genotypes potentially tolerant or resistant to iron toxicity. Thus, 90 accessions collected in the regions of Kindia and Macenta and six controls susceptible or resistant to iron toxicity (AZUCENA, BOUAKE 189, CK 73, IR64, NERICAL 19 and AURYLUX 6) were evaluated in three replicate alpha lattice designs in two sites (Sérédou and Kilissi) using 16 agromorphological traits. The results showed significant agromorphological variability of the traditional accessions at both sites for all qualitative and most quantitative traits studied. In addition, 30 local cultivars expressed similar or higher grain yields than the resistant or tolerant controls at both sites, of which 12 were found to be stable at both sites. Of the 12 cultivars identified, five were resistant and seven tolerant to iron toxicity. These 12 accessions could be used in the varietal improvement of lowland rice in Guinea Conakry. 展开更多
关键词 Local Varieties ORYZA Genetic variability Environmental Stress GUINEA
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Genetic Diversity Assessment of Moroccan Sesame(Sesamum indicum L.)Populations Using Agro-morphological Traits
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作者 Meriem El Harfi Marouane Jbilou +3 位作者 Hafida Hanine Hajar Rizki Mohamed Fechtali Abdelghani Nabloussi 《Journal of Agricultural Science and Technology(A)》 2018年第5期296-305,共10页
Genetic diversity of Moroccan sesame(Sesamum indicum L.)was analyzed for the first time using agro-morphological traits.Thirty-three sesame populations collected from Tadla region in Morocco were evaluated for 13 para... Genetic diversity of Moroccan sesame(Sesamum indicum L.)was analyzed for the first time using agro-morphological traits.Thirty-three sesame populations collected from Tadla region in Morocco were evaluated for 13 parameters in three contrasted environments,Afr-13,Afr-14 and Atj-14.Broad and significant variation among populations was observed only for three agro-morphologic traits,namely first capsule height(FCH),number of seeds per capsule(NSC)and thousand seeds weight(TSW).The respective overall averages were 71.82 cm(ranging from 65 cm to 77 cm),61.39(varying from 57 to 65)and 3.20 g(ranging from 3.0 g to 3.4 g).Environment had a highly significant effect on all studied parameters,except capsule size and oil content.The obtained mean values of parameters studied showed that environment Afr-14 was the most favorable for most of them,particularly seed yield(1.32 t/ha)and TSW(3.57 g).Significant and interesting correlations were observed between seed yield per plant(SYP)and other parameters.As relevant implication of this finding,number of capsules per plant(NCP)and NSC could be used as valuable selection criteria in sesame breeding program.However,limited and non-significant variation among sesame populations for most of parameters studied suggests that they are genetically very close and may be derived from a single cultivar or germplasm.Molecular characterization is needed to confirm or refute this hypothesis.Besides,when compared with sesame grown throughout the world,Moroccan sesame was found to be very promising,which open up the possibility to develop this crop in this country. 展开更多
关键词 Sesame(Sesamum indicum L.) Morocco Tadla REGION variability environment
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Prediction of microstructure evolution of ZK61 alloy during hot spinning by internal state variable model 被引量:2
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作者 Jin-qi PAN Wen-cong ZHANG +3 位作者 Jian-lei YANG Song-hui WANG Yong WU Huan LI 《Transactions of Nonferrous Metals Society of China》 2025年第1期126-142,共17页
An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of t... An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of the internal variables were considered in this ISV model,and the parameters were optimized by genetic algorithm.After validation,the ISV model was used to simulate the evolution of grain size(GS)and dynamic recrystallization(DRX)fraction during hot spinning via Abaqus and its subroutine Vumat.By comparing the simulated results with the experimental results,the application of the ISV model was proven to be reliable.Meanwhile,the strength of the thin-walled spun ZK61 tube increased from 303 to 334 MPa due to grain refinement by DRX and texture strengthening.Besides,some ultrafine grains(0.5μm)that played an important role in mechanical properties were formed due to the proliferation,movement,and entanglement of dislocations during the spinning process. 展开更多
关键词 internal state variable model hot spinning ZK61 alloy finite element simulation texture evolution
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Numerical Methods for Boundary Value Problems in Variable Coefficient Ordinary Differential Equations 被引量:1
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作者 ZHAO Ting-ting CAI Wei-yun 《Chinese Quarterly Journal of Mathematics》 2025年第3期295-303,共9页
In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error... In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error between the numerical solution and the exact solution is obtained,and then compared with the error formed by the difference method,it is concluded that the Lagrange interpolation method is more effective in solving the variable coefficient ordinary differential equation. 展开更多
关键词 Variable coefficient ordinary differential equations Lagrange interpolation Difference methods
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A Significant Transition of Antarctic Sea Ice Variability in Response to the Shoaling of the Circumpolar Deep Water 被引量:1
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作者 Ruonan CHEN Xiao-Yi YANG Dongxiao WANG 《Advances in Atmospheric Sciences》 2025年第12期2499-2517,共19页
As a crucial component of the Earth’s climate system,Antarctic sea ice has demonstrated significant variability over the satellite era.Here,we identify a remarkable decadal transition in the total Antarctic Sea Ice E... As a crucial component of the Earth’s climate system,Antarctic sea ice has demonstrated significant variability over the satellite era.Here,we identify a remarkable decadal transition in the total Antarctic Sea Ice Extent(SIE).The stage from 1979 to 2006 is characterized by high-frequency(i.e.,seasonal to interannual)temporal variability in SIE and zonal asymmetry in Sea Ice Concentration(SIC),which is primarily under the control of the Amundsen Sea Low(ASL).After 2007,however,sea ice changes exhibit a more spatially homogeneous pattern in SIC and a more temporally long-lasting mode in SIE.Further analysis reveals that sea ice-ocean interaction plays a major role in the low-frequency(i.e.,multiannual)variability of Antarctic sea ice from 2007−22.The related physical process is inferred to manifest as a strong coupling between the surface and the subsurface ocean layers,involving enhanced vertical convection and the downward delivery of the surface anomalies related to ice melting and freezing processes,thus maintaining the SIE anomalies for a longer time.Furthermore,this process mainly occurs in the Amundsen-Bellingshausen Sea(ABS)sector,and the weakened subsurface ocean stratification is the key factor triggering the coupling process in this region.We find that the Circumpolar Deep Water(CDW)over the ABS sector continued to shoal before 2007 and remained stable thereafter.It is speculated that the shoaling of the CDW may be a possible driver leading to the weakening of the subsurface stratification. 展开更多
关键词 Antarctic sea ice low-frequency variability coupling process ocean stratification CDW ice-ocean interaction
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Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation
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作者 Younong Li Li Dan +2 位作者 Jing Peng Qidong Yang Fuqiang Yang 《Atmospheric and Oceanic Science Letters》 2025年第1期32-38,共7页
El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation an... El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further investigation.To investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 models.The results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the future.The higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in variability.Carbon flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through temperature.This occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures. 展开更多
关键词 Carbon variability ENSO modulation CMIP6 models
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Optimizing Fine-Tuning in Quantized Language Models:An In-Depth Analysis of Key Variables
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作者 Ao Shen Zhiquan Lai +1 位作者 Dongsheng Li Xiaoyu Hu 《Computers, Materials & Continua》 SCIE EI 2025年第1期307-325,共19页
Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning paradigm.While this approach allows models to specialize in speci... Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning paradigm.While this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader deployment.Parameter-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational efficiency.Among these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA variants.Despite these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains underexplored.This study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM architectures.Our investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do so.These insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized LLMs.Moreover,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller one.This study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM fine-tuning in resource-constrained environments. 展开更多
关键词 Large-scale Language Model Parameter-Efficient Fine-Tuning parameter quantization key variable trainable parameters experimental analysis
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Interannual variability of boreal summer intraseasonal oscillation over the northwestern Pacific influenced by the Pacific Meridional Mode
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作者 Haoyu Zhou Pang-Chi Hsu +1 位作者 Lin Chen Yitian Qian 《Atmospheric and Oceanic Science Letters》 2025年第1期6-11,共6页
During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the s... During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis results.To elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget analysis.The findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern Pacific.This increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective instability.Such a process is pivotal in amplifying intraseasonal convection anomalies.The observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns. 展开更多
关键词 Boreal summer intraseasonal oscillation Interannual variability Pacific Meridional Mode Moisture budget analysis
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Assessment of Genetic Variability and Inter-Relationship for Yield Attributing Traits in Maize (Zea mays L.) Genotypes in White Nile State, Sudan
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作者 Sara Mohammed Abdalla Khalid Abdalla Osman +1 位作者 Abd Elwahab Abdalla Dafaalla Soheap Abdalrahman Yousif 《Agricultural Sciences》 2025年第2期280-289,共10页
Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly... Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly due to the use of low yielding landraces. It is necessary to carry out breeding programs that deal with the production of high yielding, adaptable new varieties. Therefore, this study aimed to estimate genetic variability, heritability, genotypic performance and interrelationships among the traits. Ten maize genotypes evaluated at White Nile Research Station Farm, Kosti, of the Agricultural Research Corporation (ARC), Wad Medani Sudan were planted in a randomized complete block design with three replications during the two seasons of 2021 and 2022. Most evaluated genotypes exhibited a wide and significant variation in the 11 measured traits. Genotypic coefficient of variation and genetic advance were recorded for days to 50% tasseling, ear diameter (cm), number of grains per row and grain yield (t/ha) in both seasons. High heritability and genetic advance were recorded for grain yield, ear length, ear height, plant height, number of rows per ear, ear weight, days to 50% tasseling, 100-grain weight and days to 50% silking. Moreover, there was a highly significant and positive correlation of grain yield with number of rows per ear (r = 0.479), ear length (r = 0.381), 100-grain weight (r = 0.344) and days to 50% tasseling (r = 0.214). The highest yielding five genotypes across the seasons were TZCOM1/ZDPSYN (4.2 t/ha), EEPVAH-3 (4.2 t/ha), F2TWLY131228 (4.1 t/ha), PVA SYN6F2 (3.9 t/ha) and EEPVAH-9 (3.8 t/ha) these were needed to check the adaptability, stability and to test major maize growing areas to make sound recommendations for release. 展开更多
关键词 Genetic variability HERITABILITY Correlation MAIZE YIELD
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Equilibrium Strategies in M/M/1 Retrial Queues with Variable Service Rate
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作者 LIU Yuanyuan YAN Zhaozeng YANG Qin 《应用概率统计》 北大核心 2025年第3期448-466,共19页
We consider a single server constant retrial queue,in which a state-dependent service policy is used to control the service rate.Customer arrival follows Poisson process,while service time and retrial time are exponen... We consider a single server constant retrial queue,in which a state-dependent service policy is used to control the service rate.Customer arrival follows Poisson process,while service time and retrial time are exponential distributions.Whenever the server is available,it admits the retrial customers into service based on a first-come first-served rule.The service rate adjusts in real-time based on the retrial queue length.An iterative algorithm is proposed to numerically solve the personal optimal problem in the fully observable scenario.Furthermore,we investigate the impact of parameters on the social optimal threshold.The effectiveness of the results is illustrated by two examples. 展开更多
关键词 variable service rate retrial queues real-time adaptability equilibrium strategies ALGORITHM
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