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Short-span interleaving based selected mapping
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作者 吴炳洋 程时昕 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期385-388,共4页
A novel interleaving based selected mapping (SLM) scheme to depress the relatively high peak power of transmit signals in multicarrier communications is proposed. In the scheme, a group of bit-level interleavers spa... A novel interleaving based selected mapping (SLM) scheme to depress the relatively high peak power of transmit signals in multicarrier communications is proposed. In the scheme, a group of bit-level interleavers spanning only a few bits are used to produce multiple sequences representing the same information, and one of the sequences resulting in the lowest peak-to-average power ratio (PAPR) is selected for transmission. The implementation of the scheme including the structure of the short-span interleaver is illustrated. The performance of this PAPR reduction scheme is investigated by simulations. This scheme exhibits a good PAPR reduction performance, and for signals of high level modulation, such as 16QAM and 64QAM, it approaches the best performance of all SLM schemes. Compared to the conventional interleaving SLM, this short-span interleaving SLM results in a very short time delay, requires very few register units for buffering, and can be easily implemented by hardware. 展开更多
关键词 multicarrier communications peak-to-average power ratio selected mapping INTERLEAVING
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An integrated method of selecting environmental covariates for predictive soil depth mapping 被引量:7
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作者 LU Yuan-yuan LIU Feng +2 位作者 ZHAO Yu-guo SONG Xiao-dong ZHANG Gan-lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第2期301-315,共15页
Environmental covariates are the basis of predictive soil mapping.Their selection determines the performance of soil mapping to a great extent,especially in cases where the number of soil samples is limited but soil s... Environmental covariates are the basis of predictive soil mapping.Their selection determines the performance of soil mapping to a great extent,especially in cases where the number of soil samples is limited but soil spatial heterogeneity is high.In this study,we proposed an integrated method to select environmental covariates for predictive soil depth mapping.First,candidate variables that may influence the development of soil depth were selected based on pedogenetic knowledge.Second,three conventional methods(Pearson correlation analysis(PsCA),generalized additive models(GAMs),and Random Forest(RF))were used to generate optimal combinations of environmental covariates.Finally,three optimal combinations were integrated to produce a final combination based on the importance and occurrence frequency of each environmental covariate.We tested this method for soil depth mapping in the upper reaches of the Heihe River Basin in Northwest China.A total of 129 soil sampling sites were collected using a representative sampling strategy,and RF and support vector machine(SVM)models were used to map soil depth.The results showed that compared to the set of environmental covariates selected by the three conventional selection methods,the set of environmental covariates selected by the proposed method achieved higher mapping accuracy.The combination from the proposed method obtained a root mean square error(RMSE)of 11.88 cm,which was 2.25–7.64 cm lower than the other methods,and an R^2 value of 0.76,which was 0.08–0.26 higher than the other methods.The results suggest that our method can be used as an alternative to the conventional methods for soil depth mapping and may also be effective for mapping other soil properties. 展开更多
关键词 ENVIRONMENTAL COVARIATE selection integrated method PREDICTIVE SOIL mapping SOIL depth
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Fine mapping and marker-assisted selection (MAS) of a low glutelin content gene in rice 被引量:18
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作者 Yi Hua WANG Shi Jia LIU +4 位作者 Su Lan JI Wen Wei ZHANG Chun Ming WANG Ling JIANG Jian Min WAN 《Cell Research》 SCIE CAS CSCD 2005年第8期622-630,共9页
Rice with low glutelin content is suitable as functional food for patients affected with diabetes and kidney failure. The fine mapping of the gene(s) responsible for low glutelin content will provide information regar... Rice with low glutelin content is suitable as functional food for patients affected with diabetes and kidney failure. The fine mapping of the gene(s) responsible for low glutelin content will provide information regarding the distribution of glutelin related genes in rice genome and will generate markers for the selection of low glutelin rice varieties. Following an SDS-PAGE screen of rice germplasm from Taihu Valley of China, Japonica selection W3660 is identified to be a novel mutant characterized with low glutelin content. For fine mapping the mutant gene for low glutelin content, F2 and F3 populations were derived from a cross between W3660 and Jingrennuo. SDS-PAGE analysis of the total endosperm protein showed that the low glutelin content trait was controlled by a single dominant nuclear gene. Genetic mapping, using SSRs, located this gene to chromosome 2, in the region between SSR2-001/SSR2-004 and RM1358. The dis- tances of the two markers to the target gene were 1.1 cM and 3.8 cM respectively. By semi-quantitative RT-PCR analysis, the transcripts of GluB4/GluB5 genes located within the region do not change. However, GluB5 gene located proximal to SSR2-001/SSR2-004 was specifically reduced. SSR profiles of seven Japonica varieties were compared with that of W3660 for loci in the relevant genetic region. The markers SSR2-004 and RM1358 were used for marker- assisted selection. The selection efficiencies of SSR2-004 and RM1358 were 96.8% and 92.7% respectively. This provides a standard starting point for the breeding of low glutelin content rice varieties in China. 展开更多
关键词 fine mapping low glutelin content marker-assisted selection mutant rice.
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Fine mapping of the powdery mildew resistance gene PmXQ-0508 in bread wheat
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作者 Zejun Qian Guohao Han +11 位作者 Ningning Yu Cheng Liu Ran Han Paula E.Jameson Jiaojiao Wang Ya Zhao Bei Xiao Ruishan Liu Jiadong Zhang Yuli Jin Hongjie Li Pengtao Ma 《The Crop Journal》 SCIE CSCD 2024年第4期1176-1184,共9页
In a wheat breeding line XQ-0508 showing consistent resistance to powdery mildew disease,a recessive gene,designated PmXQ-0508,was identified and mapped to a distal region on chromosome arm 2BS.Of three resistance-ass... In a wheat breeding line XQ-0508 showing consistent resistance to powdery mildew disease,a recessive gene,designated PmXQ-0508,was identified and mapped to a distal region on chromosome arm 2BS.Of three resistance-associated genes in this region,one encoding a protein kinase was selected as the primary candidate for PmXQ-0508.Ten closely linked DNA markers developed in the study could be used for marker-assisted selection for powdery-mildew resistance in breeding programs. 展开更多
关键词 Wheat powdery mildew PmXQ-0508 BSR-Seq Fine mapping Marker-assisted selection
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Improving model performance in mapping cropland soil organic matter using time-series remote sensing data
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作者 Xianglin Zhang Jie Xue +5 位作者 Songchao Chen Zhiqing Zhuo Zheng Wang Xueyao Chen Yi Xiao Zhou Shi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2820-2841,共22页
Faced with increasing global soil degradation,spatially explicit data on cropland soil organic matter(SOM)provides crucial data for soil carbon pool accounting,cropland quality assessment and the formulation of effect... Faced with increasing global soil degradation,spatially explicit data on cropland soil organic matter(SOM)provides crucial data for soil carbon pool accounting,cropland quality assessment and the formulation of effective management policies.As a spatial information prediction technique,digital soil mapping(DSM)has been widely used to spatially map soil information at different scales.However,the accuracy of digital SOM maps for cropland is typically lower than for other land cover types due to the inherent difficulty in precisely quantifying human disturbance.To overcome this limitation,this study systematically assessed a framework of“information extractionfeature selection-model averaging”for improving model performance in mapping cropland SOM using 462 cropland soil samples collected in Guangzhou,China in 2021.The results showed that using the framework of dynamic information extraction,feature selection and model averaging could efficiently improve the accuracy of the final predictions(R^(2):0.48 to 0.53)without having obviously negative impacts on uncertainty.Quantifying the dynamic information of the environment was an efficient way to generate covariates that are linearly and nonlinearly related to SOM,which improved the R^(2)of random forest from 0.44 to 0.48 and the R^(2)of extreme gradient boosting from 0.37to 0.43.Forward recursive feature selection(FRFS)is recommended when there are relatively few environmental covariates(<200),whereas Boruta is recommended when there are many environmental covariates(>500).The Granger-Ramanathan model averaging approach could improve the prediction accuracy and average uncertainty.When the structures of initial prediction models are similar,increasing in the number of averaging models did not have significantly positive effects on the final predictions.Given the advantages of these selected strategies over information extraction,feature selection and model averaging have a great potential for high-accuracy soil mapping at any scales,so this approach can provide more reliable references for soil conservation policy-making. 展开更多
关键词 CROPLAND soil organic matter digital soil mapping machine learning feature selection model averaging
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An Improved Selective Mapping Method for PAPR Reduction in OFDM/OQAM System 被引量:1
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作者 Guobing Cheng Huilei Li +1 位作者 Binhong Dong Shaoqian Li 《Communications and Network》 2013年第3期53-56,共4页
Orthogonal frequency division multiplex/offset QAM (OFDM/OQAM) has been proven to be a promising multi-carrier modulation (MCM) technique for the transmission of signals over multipath fading channels. However, OFDM/O... Orthogonal frequency division multiplex/offset QAM (OFDM/OQAM) has been proven to be a promising multi-carrier modulation (MCM) technique for the transmission of signals over multipath fading channels. However, OFDM/OQAM has also the intrinsic disadvantage of high peak-to-average-power ratio (PAPR) that should be alleviated. In this paper, a novel selective mapping (SLM) method is proposed for OFDM/OQAM system. Since the pulse shape may cover a few OFDM symbols, the basic principle of the proposed method is to apply the SLM method in the range of the most relevant OFDM symbols. Analysis and simulation results show that, compared to the existing SLM algorithms for OFDM/OQAM system, the proposed method has better PAPR performance and lower computation complexity. 展开更多
关键词 OFDM/OQAM PAPR REDUCTION selectIVE mapping
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Combining rough set theory and instance selection in ontology mapping 被引量:1
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作者 Qian Pengfei Wang Yinglin Zhang Shensheng 《High Technology Letters》 EI CAS 2008年第3期258-265,共8页
This paper presents a novel ontology mapping approach based on rough set theory and instance selection.In this appoach the construction approach of a rough set-based inference instance base in which the instance selec... This paper presents a novel ontology mapping approach based on rough set theory and instance selection.In this appoach the construction approach of a rough set-based inference instance base in which the instance selection(involving similarity distance,clustering set and redundancy degree)and discernibility matrix-based feature reduction are introduced respectively;and an ontology mapping approach based on multi-dimensional attribute value joint distribution is proposed.The core of this mapping aI overlapping of the inference instance space.Only valuable instances and important attributes can be selected into the ontology mapping based on the multi-dimensional attribute value joint distribution,so the sequently mapping efficiency is improved.The time complexity of the discernibility matrix-based method and the accuracy of the mapping approach are evaluated by an application example and a series of analyses and comparisons. 展开更多
关键词 ontology mapping instance selection rough set feature reduction
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CONTINUOUS SELECTION THEOREMS FOR FAN-BROWDER MAPPINGS IN TOPOLOGICAL SPACES AND THEIR APPLICATIONS
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作者 杨明歌 邓磊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第4期493-500,共8页
The concept of Fan-Browder mappings was first introduced in topological spaces without any convex structure. Then a new continuous selection theorem was obtained for the Fan-Browder mapping with range in a topological... The concept of Fan-Browder mappings was first introduced in topological spaces without any convex structure. Then a new continuous selection theorem was obtained for the Fan-Browder mapping with range in a topological space without any convex structure and noncompact domain. As applications, some fixed point theorems, coincidence theorems and a nonempty intersection theorem were given. Both the new concepts and results unify and extend many known results in recent literature. 展开更多
关键词 Fan-Browder mapping continuous selection fixed point coincidence point
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Selective Mapping Scheme for Universal Filtered Multicarrier
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作者 Akku Madhusudhan Sudhir Kumar Sharma 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1273-1282,共10页
The next step in mobile communication technology,known as 5G,is set to go live in a number of countries in the near future.New wireless applica-tions have high data rates and mobility requirements,which have posed a c... The next step in mobile communication technology,known as 5G,is set to go live in a number of countries in the near future.New wireless applica-tions have high data rates and mobility requirements,which have posed a chal-lenge to mobile communication technology researchers and designers.5G systems could benefit from the Universal Filtered Multicarrier(UFMC).UFMC is an alternate waveform to orthogonal frequency-division multiplexing(OFDM),infiltering process is performed for a sub-band of subcarriers rather than the entire band of subcarriers Inter Carrier Interference(ICI)between neighbouring users is reduced via the sub-bandfiltering process,which reduces out-of-band emissions.However,the UFMC system has a high Peak-to-Average Power Ratio(PAPR),which limits its capabilities.Metaheuristic optimization based Selective mapping(SLM)is used in this paper to optimise the UFMC-PAPR.Based on the cognitive behaviour of crows,the research study suggests an innovative metaheuristic opti-mization known as Crow Search Algorithm(CSA)for SLM optimization.Com-pared to the standard UFMC,SLM-UFMC system,and SLM-UFMC with conventional metaheuristic optimization techniques,the suggested technique sig-nificantly reduces PAPR.For the UFMC system,the suggested approach has a very low Bit Error Rate(BER). 展开更多
关键词 -Universalfiltered multicarrier(UFMC) selective mapping(slm) metaheuristic optimization crow search algorithm(CSA) bit error rate(BER)
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Peak-to-average power ratio reduction using selective mapping with unequal power distribution
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作者 E.S.Hassan XU Zhu +3 位作者 S.E.E1-Khamy M.I.Dessouky S.A.EI-Dolill F.E.Abd EI-Samie 《Journal of Central South University》 SCIE EI CAS 2012年第7期1902-1908,共7页
A new approach for peak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM) systems was proposed.This approach is based on assigning powers to the different subcarriers of OFDM... A new approach for peak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM) systems was proposed.This approach is based on assigning powers to the different subcarriers of OFDM using an unequal power distribution strategy.In addition,a reduced complexity selective mapping (RC-SLM) scheme was proposed.The proposed scheme is based on partitioning the frequency domain symbol sequence into several sub-blocks,and then each sub-block is multiplied by different phase sequences whose length is shorter than that used in the conventional SLM scheme.Then,a kind of low complexity conversions is used to replace the IFFT blocks.The performance of the proposed RC-SLM scheme along with the new approach was studied with computer simulation.The obtained results show that the proposed RC-SLM scheme is able to achieve the lowest computational complexity when compared with other low complexity schemes proposed in the literature while at the same time improves the PAPR reduction performance by about 0.3 dB. 展开更多
关键词 orthogonal frequency division multiplexing (OFDM) peak-to-average power ratio (PAPR) computational complexity selective mapping scheme
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Genome Mapping to Enhance Efficient Marker-Assisted Selection and Breeding of the Oil Palm (<i>Elaeis guineensis</i>Jacq.)
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作者 Essubalew Getachew Seyum Ngalle Hermine Bille +2 位作者 Wosene Gebreselassie Abtew Godswill Ntsomboh-Ntsefong Joseph Martin Bell 《Advances in Bioscience and Biotechnology》 2021年第12期407-425,共19页
The oil palm (<i>Elaeis</i> <i>guineensis</i> Jacq.) is one of the major cultivated crops among the economically important palm species. It is cultivated mainly for its edible oil. For a perenn... The oil palm (<i>Elaeis</i> <i>guineensis</i> Jacq.) is one of the major cultivated crops among the economically important palm species. It is cultivated mainly for its edible oil. For a perennial crop like oil palm, the use of Marker Assisted Selection (MAS) techniques helps to reduce the breeding cycle and improve the economic products. Genetic and physical maps are important for sequencing experiments since they show the exact positions of genes and other distinctive features in the chromosomal DNA. This review focuses on the role of genome mapping in oil palm breeding. It assesses the role of genome mapping in oil palm breeding and discusses the major factors affecting such mapping. Generating a high-density map governed by several factors, for instance, marker type, marker density, number of mapped population, and software used are the major issues treated. The general conclusion is that genome mapping is pivotal in the construction of a genetic linkage map. It helps to detect QTL and identify genes that control quantitative traits in oil palm. In perspective, the use of high-density molecular markers with a large number of markers, a large number mapping population, and up-to-date softw<span style="color:;">are </span><span>is necessary</span><span style="color:;"> for oil pal</span>m genome mapping. 展开更多
关键词 Genome mapping Crop Improvement Marker Assisted selection Oil Palm BIOTECHNOLOGY
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基于医学CT与SLM技术的踝关节骨骼逆向建模与制备
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作者 赵丽 刘江豪 +2 位作者 徐洋洋 刘旭波 余廷 《热加工工艺》 北大核心 2024年第13期85-88,93,共5页
基于医学CT与3D打印技术实现了骨骼重建与制造。通过对病人踝关节骨骼原始CT数据的采集,运用医学逆向工程软件Mimics及Geomagic软件对骨骼分别进行三维模型重建和骨骼曲面修复、优化,得到了骨面较为光滑平整的踝关节模型。通过对骨骼模... 基于医学CT与3D打印技术实现了骨骼重建与制造。通过对病人踝关节骨骼原始CT数据的采集,运用医学逆向工程软件Mimics及Geomagic软件对骨骼分别进行三维模型重建和骨骼曲面修复、优化,得到了骨面较为光滑平整的踝关节模型。通过对骨骼模型进行静力学分析,说明在人体结构生物力学条件下,所建立的踝关节三维模型满足力学要求。通过实验获得了TC4钛合金激光选区熔化(SLM)技术的优化工艺参数为激光功率240 W,扫描速度800 mm/s,扫描间距为0.12 mm,铺粉厚度为0.05 mm。采用该工艺参数和所建立的踝关节模型,实现了TC4钛合金踝关节3D打印逆向制造,所得制品的形状与组织成分优,满足医学使用要求。 展开更多
关键词 医学CT 3D打印 踝关节骨骼 逆向建模 激光选区熔化(slm)
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Molecular and Physical Mapping of Powdery Mildew Resistance Genes and QTLs in Wheat: A Review 被引量:7
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作者 Jun GUO Cheng LIU +8 位作者 Shengnan ZHAI Haosheng LI Aifeng LIU Dungong CHENG Ran HAN Jianjun LIU Lingrang KONG Zhendong ZHAO Jianmin SONG 《Agricultural Science & Technology》 CAS 2017年第6期965-970,共6页
Wheat powdery mildew (Pro) is a major disease of wheat worldwide. During the past years, numerous studies have been published on molecular mapping of Pm resistance gene(s) in wheat. We summarized the relevant find... Wheat powdery mildew (Pro) is a major disease of wheat worldwide. During the past years, numerous studies have been published on molecular mapping of Pm resistance gene(s) in wheat. We summarized the relevant findings of 89 major re- sistance gene mapping studies and 25 quantitative trait loci (QTL) mapping studies. Major Pm resistance genes and QTLs were found on all wheat chromosomes, but the Pm resistance genes/QTLs were not randomly distributed on each chromosome of wheat. The summarized data showed that the A or B genome has more major Pm resistance genes than the D genome and chromosomes 1A, 2A, 2B, 5B, 5D, 6B, 7A and 7B harbor more major Pm resistance genes than the other chromosomes. For adult plant resistance (APR) genes/QTLs, B genome of wheat harbors more APR genes than A and D genomes, and chromo- somes 2A, 4A, 5A, 1B, 2B, 3B, 5B, 6B, 7B, 2D, 5D and 7D harbor more Pm resistance QTLs than the other chromosomes, suggesting that A genome except 1A, 3A and 6A, B genome except 4B, D genome except 1D, 3D, 4D, and 6D play an impor- tant role in wheat combating against powdery mildew. Furthermore, Pm resistance genes are derived from wheat and its rela- tives, which suggested that the resistance sources are diverse and Pm resistance genes are diverse and useful in combating against the powdery mildew isolates. In this review, four APR genes, Pm38/Lr34/Yr18/Sr57, Pm46/Lr67/Yr46/Sr55, Pm?/Lr27/Yr30/ SY2 and Pm39/Lr46/Yr29, are not only resistant to powdery mildew but also effective for rust diseases in the field, indicating that such genes are stable and useful in wheat breeding programmes. The summarized data also provide chromosome locations or linked markers for Pm resistance genes/QTLs. Markers linked to these genes can also be utilized to pyramid diverse Pm resis- tance genes/QTLs more efficiently by marker-assisted selection. 展开更多
关键词 Wheat powdery mildew Molecular mapping Major Pm resistance genes Quantitative trait loci (QTL) Marker-assisted selection
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EXISTENCE PROBLEMS OF ADDITIVE SELECTION MAPS FOR ANOTHER TYPE SUBADDITIVE SET-VALUED MAP 被引量:1
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作者 Yongjie Piao Hailan Jin 《Analysis in Theory and Applications》 2012年第3期294-300,共7页
In this paper, we consider the following subadditive set-valued map F : X→P0(Y) :where r and s are two natural numbers. And we discuss the existence and unique problem of additive selection maps for the above set... In this paper, we consider the following subadditive set-valued map F : X→P0(Y) :where r and s are two natural numbers. And we discuss the existence and unique problem of additive selection maps for the above set-valued map. 展开更多
关键词 additive selection map subadditive additive selection CONE
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Design and Manufacture of Bionic Porous Titanium Alloy Spinal Implant Based on Selective Laser Melting(SLM) 被引量:2
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作者 Xiaojun Chen Di Wang +4 位作者 Wenhao Dou Yimeng Wang Yongqiang Yang Jianhua Wang Jie Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第9期1099-1117,共19页
In order to meet the clinical requirements of spine surgery,this paper proposed the exploratory research of computer-aided design and selective laser melting(SLM)fabrication of a bionic porous titanium spine implant.T... In order to meet the clinical requirements of spine surgery,this paper proposed the exploratory research of computer-aided design and selective laser melting(SLM)fabrication of a bionic porous titanium spine implant.The structural design of the spinal implant is based on CT scanning data to ensure correct matching,and the mechanical properties of the implant are verified by simulation analysis and laser selective melting experiment.The surface roughness of the spinal implant manufactured by SLM without post-processing is Ra 15μm,and the implant is precisely jointed with the photosensitive resin model of the upper and lower spine.The surface micro-hardness of the implant is HV 373,tensile strengthσ_(b)=1238.7 MPa,yield strengthσ_(0.2)=1043.9 MPa,the elongation is 6.43%,and the compressive strength of porous structure under 84.60%porosity is 184.09 MPa,which can meet the requirements of the reconstruction of stable spines.Compared with the traditional implant and intervertebral fusion cage,the bionic porous spinal implant has the advantages of accurate fit,porous bionic structure and recovery of patients,and the ion release experiment proved that implants manufactured by SLM are more suitable for clinical application after certain treatments.The elastic modulus of the sample is improved after heat treatment,mainly because the microstructure of the sample changes fromα’phase toα+βdual-phase after heat treatment.In addition,the design of high-quality bionic porous spinal implants still needs to be optimized for the actual needs of doctors. 展开更多
关键词 selective laser melting(slm) titanium spinal implant bionic porous
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The Unique Existence of Additive Selection Maps for a Weak Subadditive Set-valued Map 被引量:1
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作者 PIAO Yong-jie SHI Ren-shu 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第1期53-59,共7页
In this paper, we discuss the unique existent problems of a additive selection map for the following map F:X→P0(Y):F(r∑i=1αixi)■r∑i=1αiF(xi),■xi∈K,i=1, ··· , r,where αi and αi (i = 1, ·&#... In this paper, we discuss the unique existent problems of a additive selection map for the following map F:X→P0(Y):F(r∑i=1αixi)■r∑i=1αiF(xi),■xi∈K,i=1, ··· , r,where αi and αi (i = 1, ··· , r) are all non-negative real numbers. 展开更多
关键词 additive selection map subadditive additive selection CONE
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Rice molecular markers and genetic mapping:Current status and prospects 被引量:4
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作者 Ghulam Shabir Kashif Aslam +8 位作者 Abdul Rehman Khan Muhammad Shahid Hamid Manzoor Sibgha Noreen Mueen Alam Khan Muhammad Baber Muhammad Sabar Shahid Masood Shah Muhammad Arif 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第9期1879-1891,共13页
Dramatic changes in climatic conditions that supplement the biotic and abiotic stresses pose severe threat to the sustainable rice production and have made it a difficult task for rice molecular breeders to enhance pr... Dramatic changes in climatic conditions that supplement the biotic and abiotic stresses pose severe threat to the sustainable rice production and have made it a difficult task for rice molecular breeders to enhance production and productivity under these stress factors. The main focus of rice molecular breeders is to understand the fundamentals of molecular pathways involved in complex agronomic traits to increase the yield. The availability of complete rice genome sequence and recent improvements in rice genomics research has made it possible to detect and map accurately a large number of genes by using linkage to DNA markers. Linkage mapping is an effective approach to identify the genetic markers which are co-segregating with target traits within the family. The ideas of genetic diversity, quantitative trait locus(QTL) mapping, and marker-assisted selection(MAS) are evolving into more efficient concepts of linkage disequilibrium(LD) also called association mapping and genomic selection(GS), respectively. The use of cost-effective DNA markers derived from the fine mapped position of the genes for important agronomic traits will provide opportunities for breeders to develop high-yielding, stress-resistant, and better quality rice cultivars. Here we focus on the progress of molecular marker technologies, their application in genetic mapping and evolution of association mapping techniques in rice. 展开更多
关键词 genetic mapping molecular markers maker assisted selection Oryza sativa L quantitative trait loci
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CSMCCVA:Framework of cross-modal semantic mapping based on cognitive computing of visual and auditory sensations 被引量:1
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作者 刘扬 Zheng Fengbin Zuo Xianyu 《High Technology Letters》 EI CAS 2016年第1期90-98,共9页
Cross-modal semantic mapping and cross-media retrieval are key problems of the multimedia search engine.This study analyzes the hierarchy,the functionality,and the structure in the visual and auditory sensations of co... Cross-modal semantic mapping and cross-media retrieval are key problems of the multimedia search engine.This study analyzes the hierarchy,the functionality,and the structure in the visual and auditory sensations of cognitive system,and establishes a brain-like cross-modal semantic mapping framework based on cognitive computing of visual and auditory sensations.The mechanism of visual-auditory multisensory integration,selective attention in thalamo-cortical,emotional control in limbic system and the memory-enhancing in hippocampal were considered in the framework.Then,the algorithms of cross-modal semantic mapping were given.Experimental results show that the framework can be effectively applied to the cross-modal semantic mapping,and also provides an important significance for brain-like computing of non-von Neumann structure. 展开更多
关键词 multimedia neural cognitive computing (MNCC) brain-like computing cross-modal semantic mapping (CSM) selective attention limbic system multisensory integration memory-enhancing mechanism
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面向混合波束成形结构的改进SLM算法
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作者 肖迪笙 胡世成 +2 位作者 钱骅 康凯 李明齐 《中国科学院大学学报(中英文)》 CAS CSCD 北大核心 2024年第6期786-793,共8页
在大规模多输入多输出系统中,峰均功率比(PAPR)是影响发射机性能的主要因素之一。传统的PAPR降低方法都是基于全数字编码结构,无法有效地降低混合波束成形结构中发射天线端信号的PAPR。为解决这一问题,提出一种改进选择性映射(SLM)算法... 在大规模多输入多输出系统中,峰均功率比(PAPR)是影响发射机性能的主要因素之一。传统的PAPR降低方法都是基于全数字编码结构,无法有效地降低混合波束成形结构中发射天线端信号的PAPR。为解决这一问题,提出一种改进选择性映射(SLM)算法,该方法对输入信号进行独立的相位旋转并计算发射天线端信号的PAPR,最后选取PAPR最小的一组信号进行发送。此外,还分析了使用该算法下发射天线端信号PAPR的上界和下界。理论分析与仿真结果显示,改进SLM算法能够有效地降低混合波束成形结构发射天线端信号的PAPR。 展开更多
关键词 大规模多输入多输出 混合波束成形 峰均功率比(PAPR) 选择性映射(slm)
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铝合金叶轮SLM成型摆放及支撑方案仿真与实验
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作者 亢红叶 龚海军 +4 位作者 张梦祥 张旸 段虎明 唐刚志 张继祥 《热加工工艺》 北大核心 2024年第19期60-66,共7页
为减少选区激光熔化成型试错次数并高效打印某铝合金潜水泵叶轮,使用ANSYS软件模拟不同摆放和支撑设计方案下叶轮SLM成型过程中的应力、变形和刮刀碰撞。通过对比确定叶轮正置为最优的设计方案,并进行了SLM成型。试制叶轮外表无裂纹和... 为减少选区激光熔化成型试错次数并高效打印某铝合金潜水泵叶轮,使用ANSYS软件模拟不同摆放和支撑设计方案下叶轮SLM成型过程中的应力、变形和刮刀碰撞。通过对比确定叶轮正置为最优的设计方案,并进行了SLM成型。试制叶轮外表无裂纹和明显变形,内部无大孔隙。对叶轮进行激光扫描偏差分析,发现平均偏差为0.106mm。退火后,试棒抗拉强度可达257~264 MPa,断后伸长率为11%~12%。可见,叶轮SLM成型过程仿真可为同类结构铝合金零件SLM成型摆放与支撑设计提供有益参考。 展开更多
关键词 潜水泵叶轮 铝合金 选区激光熔化 摆放与支撑
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