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A position distribution measurement method and mathematical modeling of two projectiles simultaneous hitting target based on three photoelectric encoder detection screens
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作者 Hanshan Li Zixuan Cao Xiaoqian Zhang 《Defence Technology(防务技术)》 2025年第11期151-168,共18页
To solve the problem of identification and measurement of two projectiles hitting the target at the same time,this paper proposes a projectile coordinate test method combining three photoelectric encoder detection scr... To solve the problem of identification and measurement of two projectiles hitting the target at the same time,this paper proposes a projectile coordinate test method combining three photoelectric encoder detection screens,and establishes a coordinate calculation model for two projectiles to reach the same detection screen at the same time.The design method of three photoelectric encoder detection screens and the position coordinate recognition algorithm of the blocked array photoelectric detector when projectile passing through the photoelectric encoder detection screen are studied.Using the screen projection method,the intersected linear equation of the projectile and the line laser with the main detection screen as the core coordinate plane is established,and the projectile coordinate data set formed by any two photoelectric encoder detection screens is constructed.The principle of minimum error of coordinate data set is used to determine the coordinates of two projectiles hitting the target at the same time.The rationality and feasibility of the proposed test method are verified by experiments and comparative tests. 展开更多
关键词 Photoelectric encoder detection screen PROJECTILE Matching and recognition Linear laser Position distribution
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基于Filter Encoding的GML空间数据查询 被引量:3
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作者 苗立志 张书亮 +2 位作者 伍蓝 闾国年 焦东来 《计算机工程》 CAS CSCD 北大核心 2008年第3期59-61,共3页
随着地理数据网络化程度的提高和GML空间数据的应用越来越广泛,如何从海量的GML空间数据中检索出符合特定条件的地理要素数据成为目前GML研究的焦点问题之一。该文根据OGC制定的过滤编码执行规程,应用规程中的谓词作为查询关键字,结合GM... 随着地理数据网络化程度的提高和GML空间数据的应用越来越广泛,如何从海量的GML空间数据中检索出符合特定条件的地理要素数据成为目前GML研究的焦点问题之一。该文根据OGC制定的过滤编码执行规程,应用规程中的谓词作为查询关键字,结合GML空间数据的特点,通过查询转译器和优化器实现了一种应用于GML空间数据查询的可行性方法。 展开更多
关键词 查询转译器 查询优化器 过滤编码
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Fast encoding algorithm for vector quantization based on subvector L_2-norm 被引量:1
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作者 Chen Shanxue Li Fangwei Zhu Weile 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期611-617,共7页
A fast encoding algorithm based on the mean square error (MSE) distortion for vector quantization is introduced. The vector, which is effectively constructed with wavelet transform (WT) coefficients of images, can... A fast encoding algorithm based on the mean square error (MSE) distortion for vector quantization is introduced. The vector, which is effectively constructed with wavelet transform (WT) coefficients of images, can simplify the realization of the non-linear interpolated vector quantization (NLIVQ) technique and make the partial distance search (PDS) algorithm more efficient. Utilizing the relationship of vector L2-norm and its Euclidean distance, some conditions of eliminating unnecessary codewords are obtained. Further, using inequality constructed by the subvector L2-norm, more unnecessary codewords are eliminated. During the search process for code, mostly unlikely codewords can be rejected by the proposed algorithm combined with the non-linear interpolated vector quantization technique and the partial distance search technique. The experimental results show that the reduction of computation is outstanding in the encoding time and complexity against the full search method. 展开更多
关键词 image compression fast encoding subvector wavelet transform vector quantization.
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Dynamic matrix encoding strategy for voice-over-IP steganography 被引量:5
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作者 田晖 周可 冯丹 《Journal of Central South University》 SCIE EI CAS 2010年第6期1285-1292,共8页
In order to optionally regulate embedding capacity and embedding transparency according to user's requirements in voice-over-IP(VoIP) steganography,a dynamic matrix encoding strategy(DMES) was presented.Differing ... In order to optionally regulate embedding capacity and embedding transparency according to user's requirements in voice-over-IP(VoIP) steganography,a dynamic matrix encoding strategy(DMES) was presented.Differing from the traditional matrix encoding strategy,DMES dynamically chose the size of each message group in a given set of adoptable message sizes.The appearance possibilities of all adoptable sizes were set in accordance with the desired embedding performance(embedding rate or bit-change rate).Accordingly,a searching algorithm that could provide an optimal combination of appearance possibilities was proposed.Furthermore,the roulette wheel algorithm was employed to determine the size of each message group according to the optimal combination of appearance possibilities.The effectiveness of DMES was evaluated in StegVoIP,which is a typical covert communication system based on VoIP.The experimental results demonstrate that DMES can adjust embedding capacity and embedding transparency effectively and flexibly,and achieve the desired embedding performance in any case.For the desired embedding rate,the average errors are not more than 0.000 8,and the standard deviations are not more than 0.002 0;for the desired bit-change rate,the average errors are not more than 0.001 4,and the standard deviations are not more than 0.002 6. 展开更多
关键词 STEGANOGRAPHY embedding transparency dynamic matrix encoding strategy voice over IP
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Therapeutic effect of intravesical or intratumoral injection of oncolysate transfected with recombinant vaccinia virus encoding human IL-2 gene on murine melanoma model 被引量:1
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作者 Bruce Acres 《中国实验血液学杂志》 CAS CSCD 1997年第3期317-317,共1页
Oncolysate, a debris of tumor cells, has been provento be effective in tumor active immunotherapy, it wasreported that the vaccinia virus, especially recombinantvaccinia viruses encoding human IL-2 (rVV-IL-2 ),enhance... Oncolysate, a debris of tumor cells, has been provento be effective in tumor active immunotherapy, it wasreported that the vaccinia virus, especially recombinantvaccinia viruses encoding human IL-2 (rVV-IL-2 ),enhanced the immunogenicity of transfected tumor cells.In this experiment, the murine melanoma cell B16-F10oncolysates trans fected by rVV-IL-2 (IL-2VBO) wereused as vaccine. The IL-2VBO or TK-VBO was preparedby incubating B16-F10 cells with rVV-IL-2 or rVV-TK 展开更多
关键词 MELANOMA encoding immunotherapy DEBRIS MURINE vaccine PROLONGED inhibited cytotoxicity markedly
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苹果NBS-encoding基因对斑点落叶病菌侵染的表达响应 被引量:2
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作者 童月霞 胡晓璇 +1 位作者 程宗明 仲岩 《南京农业大学学报》 CAS CSCD 北大核心 2019年第2期253-260,共8页
[目的]本文旨在分析苹果差异表达NBS-encoding基因的特征,挖掘在苹果斑点落叶病菌侵染过程中的潜在响应基因。[方法]通过苹果斑点落叶病菌侵染‘红星’后的RNA-seq数据筛选出差异表达的NBS-encoding基因,并利用ProtParam、Pfam、SMART... [目的]本文旨在分析苹果差异表达NBS-encoding基因的特征,挖掘在苹果斑点落叶病菌侵染过程中的潜在响应基因。[方法]通过苹果斑点落叶病菌侵染‘红星’后的RNA-seq数据筛选出差异表达的NBS-encoding基因,并利用ProtParam、Pfam、SMART等网站分析了其理化性质;利用R studio软件构建表达热图并分析其表达模式;利用Fast Tree 2软件构建苹果NBS-encoding基因家族的系统进化树,并利用MEGA 6.0软件计算差异表达的NBS-encoding基因所在系统进化支的Ka/Ks值,研究NBS-encoding基因在进化过程中受到的选择压力;利用Cytoscape 3.0软件构建共表达网络图,分析NBS-encoding基因之间的关联性。[结果]共筛选得到了19个差异表达NBS-encoding基因。表达模式分析表明,有3个基因(登录号为MDP0000259862、MDP0000304378和MDP0000292810)可能在响应苹果斑点落叶病的过程中起了关键作用。19个差异表达基因分布在系统进化树的15个进化支中,其中进化支10、12、14、15的平均Ka/Ks值均大于1,说明这些进化支中的基因受到正选择压力的作用,尤其是登录号为MDP0000210357、MDP0000751628、MDP0000147704和MDP0000372663的基因;而其余15个NBS-encoding基因的平均Ka/Ks值均小于1,说明它们受到纯化选择的作用。此外,有16个基因处于同一个共表达网络中,登录号为MDP0000210357、MDP0000240537和MDP0000291205的基因扮演着重要的角色。[结论]19个苹果NBS-encoding基因参与苹果斑点落叶病菌侵染后的响应过程,其中登录号为MDP0000259862、MDP0000304378、MDP0000292810、MDP0000210357、MDP0000240537和MDP0000291205的基因可作为候选基因进行苹果抗病品种选育。 展开更多
关键词 苹果斑点落叶病 NBS-encoding基因 表达模式 选择压力 共表达网络
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Computationally efficient direction finding using polynomial rooting with reduced-order and real-valued computations 被引量:3
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作者 Fenggang Yan Yi Shen +1 位作者 Ming Jin Xiaolin Qiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第4期739-745,共7页
The root multiple signal classification(root-MUSIC) algorithm is one of the most important techniques for direction of arrival(DOA) estimation. Using a uniform linear array(ULA) composed of M sensors, this metho... The root multiple signal classification(root-MUSIC) algorithm is one of the most important techniques for direction of arrival(DOA) estimation. Using a uniform linear array(ULA) composed of M sensors, this method usually estimates L signal DOAs by finding roots that lie closest to the unit circle of a(2M-1)-order polynomial, where L 〈 M. A novel efficient root-MUSIC-based method for direction estimation is presented, in which the order of polynomial is efficiently reduced to 2L. Compared with the unitary root-MUSIC(U-root-MUSIC) approach which involves real-valued computations only in the subspace decomposition stage, both tasks of subspace decomposition and polynomial rooting are implemented with real-valued computations in the new technique,which hence shows a significant efficiency advantage over most state-of-the-art techniques. Numerical simulations are conducted to verify the correctness and efficiency of the new estimator. 展开更多
关键词 direction-of-arrival(DOA) estimation root multiple signal classification(root-MUSIC) real-valued computations reduced-order
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Novel joint encoding/decoding algorithms of fountain codes for underwater acoustic communication 被引量:1
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作者 Mingshen Liang Jinjue Duan +2 位作者 Danfeng Zhao Jiaxi Si Xiangyu Song 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第4期772-779,共8页
Fountain codes are considered to be a promising coding technique in underwater acoustic communication(UAC) which is challenged with the unique propagation features of the underwater acoustic channel and the harsh ma... Fountain codes are considered to be a promising coding technique in underwater acoustic communication(UAC) which is challenged with the unique propagation features of the underwater acoustic channel and the harsh marine environment. And Luby transform(LT) codes are the first codes fully realizing the digital fountain concept. However, in conventional LT encoding/decoding algorithms, due to the imperfect coverage(IC) of input symbols and short cycles in the generator matrix, stopping sets would occur and terminate the decoding. Thus, the recovery probability is reduced,high coding overhead is required and decoding delay is increased.These issues would be disadvantages while applying LT codes in underwater acoustic communication. Aimed at solving those issues, novel encoding/decoding algorithms are proposed. First,a doping and non-uniform selecting(DNS) encoding algorithm is proposed to solve the IC and the generation of short cycles problems. And this can reduce the probability of stopping sets occur during decoding. Second, a hybrid on the fly Gaussian elimination and belief propagation(OFG-BP) decoding algorithm is designed to reduce the decoding delay and efficiently utilize the information of stopping sets. Comparisons via Monte Carlo simulation confirm that the proposed schemes could achieve better overall decoding performances in comparison with conventional schemes. 展开更多
关键词 underwater acoustic communication(UAC) fountain codes non-uniform encoding hybrid decoding algorithm stopping sets
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Cloning and Characterization of a Tau Glutathione S-transferase Subunit Encoding Gene in Gossypium hirsutum 被引量:3
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作者 MA Zhi-ying,LI Zhi-kun,WANG Xing-fen,MA Jun,ZHANG Gui-yin(Agricultural University of Hebei,Baoding 071001,China) 《棉花学报》 CSCD 北大核心 2008年第S1期61-,共1页
A predicted tau glutathione S-transferase(GST) subunit encoding gene,named GhGST,was isolated from Gossypium hirsutum with RACE method from SSH library based on Verticillium
关键词 Cloning and Characterization of a Tau Glutathione S-transferase Subunit encoding Gene in Gossypium hirsutum
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In vivo gene therapy of murine melanoma mediated by recombinant vaccinia virus encoding human IL-2 gene
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作者 Bruce Acres 《中国实验血液学杂志》 CAS CSCD 1997年第3期317-318,共2页
Direct gene transfer into somatic tissue in vivo is adeveloping technology with potential application forcancer gene therapy. Retrovirus vector, which was aneffective vehicle, still has some disadvantages ingenerating... Direct gene transfer into somatic tissue in vivo is adeveloping technology with potential application forcancer gene therapy. Retrovirus vector, which was aneffective vehicle, still has some disadvantages ingenerating high titer recombinant vectors andmanipulating to mediate in viro gene transfer. In thispaper, recombinant vaccinia virus vector encoding 展开更多
关键词 MELANOMA encoding disadvantages SOMATIC MURINE TITER transfection HOMOLOGOUS expanded plaque
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The development and characterization ot recombinant adenovirus encoding RA538, p53 or p16 for gene therapy of cancer
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作者 Jinke Cheng, Chen Lin, Xueyan Zhang, Rong Xing, Juwei Mu, Min WuNational Laboratory of Molecular Oncology, Cancer Institute, Chinese Academy of Medical Sciences, and Peking Union Medical College, Beijing 100021 《中国实验血液学杂志》 CAS CSCD 1997年第3期331-332,共2页
We have constructed three recombinantadenoviruses encoding RA538, p53 or p16 respec-tively. These recombinant adenoviruses are able toexpress RA538, p53 or p16 in infected human cancercells. The transduction efficienc... We have constructed three recombinantadenoviruses encoding RA538, p53 or p16 respec-tively. These recombinant adenoviruses are able toexpress RA538, p53 or p16 in infected human cancercells. The transduction efficiency assay showed thatthe infected cancer cells inoculated with theserecombinant adenoviruses at MOI of 25 or greaterexhibited 100% transduction efficiency. The growthrates and colony formation of cancer cells infectedwith these recombinant adenoviruses were 展开更多
关键词 ADENOVIRUS encoding infected transduction CYTOMETRY inoculated colony SUBCUTANEOUS NUDE arrest
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Improved encoding structure and decoding algorithms for spinal codes
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作者 HUANG Wensha WANG Lina 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第4期856-866,共11页
To improve the error correction performance, an innovative encoding structure with tail-biting for spinal codes is designed. Furthermore, an adaptive forward stack decoding(A-FSD) algorithm with lower complexity for s... To improve the error correction performance, an innovative encoding structure with tail-biting for spinal codes is designed. Furthermore, an adaptive forward stack decoding(A-FSD) algorithm with lower complexity for spinal codes is proposed. In the A-FSD algorithm, a flexible threshold parameter is set by a variable channel state to narrow the scale of nodes accessed. On this basis, a new decoding method of AFSD with early termination(AFSD-ET) is further proposed. The AFSD-ET decoder not only has the ability of dynamically modifying the number of stored nodes, but also adopts the early termination criterion to curtail complexity. The complexity and related parameters are verified through a series of simulations. The simulation results show that the proposed spinal codes with tail-biting and the AFSD-ET decoding algorithms can reduce the complexity and improve the decoding rate without sacrificing correct decoding performance. 展开更多
关键词 spinal code tail-biting encoding lower decoding complexity early termination strategy
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Identification and Cloning of Resistance Gene Analogues (RGAs) Encoding NBS-LRR Proteins from Gossypium arboreum L.
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作者 AZHAR Muhammad Tehseen BASHIR Aftab BRIDDON Rob W MANSOOR Shahid 《棉花学报》 CSCD 北大核心 2008年第S1期42-,共1页
Plants have developed a complicated defense mechanism during evolution to resist the harmful pathogens they encountered.The mechanism involves the interaction of the plant resistance(R)
关键词 NBS encoding NBS-LRR Proteins from Gossypium arboreum L Identification and Cloning of Resistance Gene Analogues LRR RGAs
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基于时空Transformer-encoder的跨社交网络用户匹配方法
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作者 张洋 马强 《计算机应用研究》 CSCD 北大核心 2024年第12期3742-3748,共7页
针对目前基于签到时空数据的跨社交网络用户匹配方法未充分利用时空信息之间的耦合关系,导致时空数据特征提取困难,匹配准确率下降的问题,提出了一种基于时空Transformer-encoder的跨社交网络用户匹配方法。该方法通过网格映射将签到时... 针对目前基于签到时空数据的跨社交网络用户匹配方法未充分利用时空信息之间的耦合关系,导致时空数据特征提取困难,匹配准确率下降的问题,提出了一种基于时空Transformer-encoder的跨社交网络用户匹配方法。该方法通过网格映射将签到时空信息转换为序列数据,生成签到序列;利用序列嵌入层将离散的签到序列映射到连续高维空间;然后借助多头注意力机制和卷积神经网络提取高维签到特征,并利用卷积神经网络实现优化多头注意力模块权重变换和特征融合;最后利用前馈神经网络实现分类,输出用户匹配得分。在两组真实社交网络用户数据集上进行大量用户匹配实验,与现有方法相比,准确率提升了0.40~10.53百分点,F_(1)值提升了0.43~9.5百分点。这验证了所提方法能够有效提取用户签到耦合特征,并提高用户匹配的性能。 展开更多
关键词 跨社交网络 用户匹配 Transformer-encoder 卷积神经网络
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An Improved Method of Linear Encoding Representation-A Cell Linear Quadtree
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作者 He Yu Zhang Qianren Ye Yizheng Li Zhongrong (Department of Computer science) 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 1990年第3期28-31,共4页
The linear encoding of a quadtree is an efficient way to represent the quadtree. In this paper, an improved linear quadtree, a cell linear quadtree, is proposed, in which its redundant storage is eliminated and the co... The linear encoding of a quadtree is an efficient way to represent the quadtree. In this paper, an improved linear quadtree, a cell linear quadtree, is proposed, in which its redundant storage is eliminated and the concept of a cell is introduced. Therefore, it has higher storage efficiency than a conventional linear quadtree. 展开更多
关键词 分支树 图像处理 图像编码 层状数据结构 编码表达法
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基于集成学习的恶意代码动态检测方法 被引量:1
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作者 刘强 王坚 +1 位作者 王亚男 王珊 《信息网络安全》 北大核心 2025年第1期159-172,共14页
在当前网络环境中,不断升级的恶意代码变种为网络安全带来了巨大挑战。现有的人工智能模型虽然在恶意代码检测方面成效明显,但仍存在两个不可忽视的缺点。一是泛化能力较差,虽然在训练数据上表现优异,但受概念漂移现象的影响,在实际测... 在当前网络环境中,不断升级的恶意代码变种为网络安全带来了巨大挑战。现有的人工智能模型虽然在恶意代码检测方面成效明显,但仍存在两个不可忽视的缺点。一是泛化能力较差,虽然在训练数据上表现优异,但受概念漂移现象的影响,在实际测试中性能不够理想;二是鲁棒性不佳,容易受到对抗样本的攻击。为解决上述问题,文章提出一种基于集成学习的恶意代码动态检测方法,根据API序列的不同特征,分别构建统计特征分析模块、语义特征分析模块和结构特征分析模块,各模块针对性地进行恶意代码检测,最后融合各模块分析结果,得出最终检测结论。在Speakeasy数据集上的实验结果表明,与现有研究方法相比,该方法各项性能指标具有明显优势,同时具有较好的鲁棒性,能够有效抵抗针对API序列的两种对抗攻击。 展开更多
关键词 恶意代码检测 n-gram算法 Transformer编码器 图神经网络 对抗性攻击
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基于SCADA参量耦合网络变分图自编码的风电机组异常检测方法 被引量:2
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作者 刘小峰 李俊锋 柏林 《太阳能学报》 北大核心 2025年第5期567-576,共10页
利用风电机组数据采集与监控系统(SCADA)数据监测参量本身数值信息及其相互间的耦合关联性,提出基于多参量耦合关系变分图自编码的风电机组异常检测方法。该方法利用时间序列自适应符号传递熵构建SCADA数据的参量耦合关系网络,设计变分... 利用风电机组数据采集与监控系统(SCADA)数据监测参量本身数值信息及其相互间的耦合关联性,提出基于多参量耦合关系变分图自编码的风电机组异常检测方法。该方法利用时间序列自适应符号传递熵构建SCADA数据的参量耦合关系网络,设计变分图自编码再编码模型对参量耦合关系网络进行编码重构。结合SCADA参量耦合关系网络的编码重构误差构建风电机组的健康状态评估指标,采用支持向量回归的迭代更新法,对机组实时健康阈值进行自适应设置。两个风场的风力发电机组SCADA数据分析结果表明:该文方法充分利用了SCADA数据本身的数值信息及耦合关系结构信息,有效提高了风电机组异常状态检测的准确性及对环境工况的鲁棒性。 展开更多
关键词 风电机组 多参量耦合 变分图自编码 健康指数 异常检测
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基于Radix-4 Booth编码的并行乘法器设计 被引量:1
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作者 范文兵 周健章 《郑州大学学报(工学版)》 CAS 北大核心 2025年第1期26-33,共8页
速度和面积是评价乘法器单元性能优劣的两个基本指标。针对当前乘法器设计难以平衡版图面积和传输延时的问题,采用Radix-4 Booth算法,设计了一种新型的16位有符号定点乘法器。在部分积生成过程中,首先改进对乘数的取补码电路,然后优化... 速度和面积是评价乘法器单元性能优劣的两个基本指标。针对当前乘法器设计难以平衡版图面积和传输延时的问题,采用Radix-4 Booth算法,设计了一种新型的16位有符号定点乘法器。在部分积生成过程中,首先改进对乘数的取补码电路,然后优化基数为4的改进Booth编码器和解码器,此结构采用较少的逻辑门资源,并且易对输入比特进行并行化处理。在Wallace压缩电路中,对符号扩展位进行预处理并设计新的压缩器结构,优化整个Wallace压缩模块。在第二级压缩过程中提前对高位使用纹波进位加法器结构计算,减小了多bit伪和的求和位数。在求和电路中,使用两级超前进位加法器结构,在缩短关键路径传输延时的同时避免增大芯片面积,提高了乘法器的运行速度。新型定点乘法器与已有的乘法器结构相比,减少了12.0%的面积,降低了20.5%的延时。 展开更多
关键词 Radix-4 Booth编码 面积 传输延时 编码器 解码器 Wallace压缩
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基于二次调制双通道同步的高分辨力绝对式时栅角位移传感器 被引量:1
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作者 杨继森 秦小东 +2 位作者 桂强 徐杰 刘家红 《仪器仪表学报》 北大核心 2025年第2期314-324,共11页
为了在不增加传感器尺寸的前提下,提高传感器的分辨力和测量精度,并实现绝对角位移测量,以满足空间受限的工业场合应用需求,故提出了一种基于二次调制双通道同步的高分辨力绝对式时栅角位移传感器设计方案。该传感器主要由定尺、动尺和... 为了在不增加传感器尺寸的前提下,提高传感器的分辨力和测量精度,并实现绝对角位移测量,以满足空间受限的工业场合应用需求,故提出了一种基于二次调制双通道同步的高分辨力绝对式时栅角位移传感器设计方案。该传感器主要由定尺、动尺和驱动电路板组成,定尺上设置有精机码道的两路激励线圈、粗机码道的两路感应线圈、电磁耦合线圈的次级,动尺上设置有精机码道的两路感应线圈、粗机码道的两路激励线圈、电磁耦合线圈的初级,驱动电路板上设置有一组驱动信号发生电路、两组感应信号处理电路、FPGA核心电路。将动尺上精机码道的两路感应线圈与粗机码道的两路激励线圈串联在一起实现二次调制,当传感器精机码道的激励线圈上电工作时,精机码道的两路感应线圈上所感应的两路角位移电信号被调制到粗机码道上,从而实现了粗机码道与精机码道分辨力相加的目的,以此提升传感器的分辨力。同时将一路精机感应信号通过电磁耦合线圈回传到定尺端作为整周定位信号。通过FPGA同步解算这两路信号,实现绝对角位移测量。采用PCB工艺制作了外径为140 mm的传感器样机。实验结果表明,该传感器只需要一组驱动电路就能够实现绝对角位移测量,且分辨力从0.38″提升到0.2″,提高了47%,原始测量误差范围从±34.14″降低到±16.06″,降低了53%。 展开更多
关键词 角位移传感器 绝对式 二次调制 同步测量
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基于遗传算法的被动式木窗材下料优化 被引量:1
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作者 任长清 武子棋 +2 位作者 闫杰 丁星尘 杨春梅 《森林工程》 北大核心 2025年第3期595-602,共8页
在定制化被动式木窗加工过程中,减少边框材下料过程中的原料浪费是降低成本的关键。为此,将该问题建模为一维下料问题,针对传统遗传算法中个体编码方式在迭代过程中容易导致切割模式被破坏和探索效率低下的问题,提出一种新的个体编码方... 在定制化被动式木窗加工过程中,减少边框材下料过程中的原料浪费是降低成本的关键。为此,将该问题建模为一维下料问题,针对传统遗传算法中个体编码方式在迭代过程中容易导致切割模式被破坏和探索效率低下的问题,提出一种新的个体编码方式,以保护进化过程中切割模式的完整性。同时,设计启发式策略和修正策略,用于个体修正和种群进化。仿真试验表明,在不同算例下,除末根外的原料平均利用率均可达到99%,且末根余料长度相较其他算法也有所提高。在2组企业的实际生产数据中,与企业现有软件相比,该算法不仅达到了理论下界,还在除末根外的平均利用率上分别达到99.49%和99.66%,优于企业软件的计算结果。该算法有助于降低成本,能为工程实践提供可靠的解决方案。 展开更多
关键词 一维下料问题 遗传算法 启发式算法 种群编码 可用剩余物
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