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New Approach to Synchronize General Relativity and Quantum Mechanics with Constant “K”-Resulting Dark Matter as a New Fundamental Force Particle
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作者 Siva Prasad Kodukula 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期292-302,共11页
Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction a... Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction and expansion forces of space time. According to this, the space time with Planck diameter is a flat space time. This is the only diameter of space time that can be used as signal transformation in special relativity. This space time diameter defines the fundamental force which belongs to that space time. In quantum mechanics, this space time diameter is only the quantum of space which belongs to that particular fundamental force. Einstein’s general relativity equation and Planck parameters of quantum mechanics have been written in terms of equations containing a constant “K”, thus found a new equation for transformation of general relativity space time in to quantum space time. In this process of synchronization, there is a possibility of a new fundamental force between electromagnetic and gravitational forces with Planck length as its space time diameter. It is proposed that dark matter is that fundamental force carrying particle. By grand unification equation with space-time diameter, we found a coupling constant as per standard model “α<sub>s</sub>” for that fundamental force is 1.08 × 10<sup>-23</sup>. Its energy calculated as 113 MeV. A group of experimental scientists reported the energy of dark matter particle as 17 MeV. Thorough review may advance science further. 展开更多
关键词 General Relativity Quantum mechanics Space Time Dark Matter A New Fundamental Constant k
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Mechanism of Na and K Substitutions in Bioapatite Within Salty Area
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作者 LI Zhen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期86-86,共1页
Introduction Na and K are two most important cations in salty water,and also are two typical ions in animals’body fluids.The mineral,bioapatite,is a form of carbonated hydroxylapatite,which makes up over 50 wt.%of bones
关键词 bone NA mechanism of Na and k Substitutions in Bioapatite Within Salty Area
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AN INVESTIGATION ON THE MECHANISM OF SUPERCONDUCTIVITY IN ALKALI-DOPED BUCKMINSTERFULLERENE A_3C_(60)(A=K,Rb,Cs)
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作者 Ji Min YAN Institute of Chemistry,Academia Sinica,Beijing 100080 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期159-162,共4页
For the superconductors(Rb_xK_(1-x))_3C_(60)(x=0.1),according to BCS theory and assuming that the virtual phonon acting on electron-pair is corresponding to the intrasolecular vibration in the bnckminnterfullerene C_(... For the superconductors(Rb_xK_(1-x))_3C_(60)(x=0.1),according to BCS theory and assuming that the virtual phonon acting on electron-pair is corresponding to the intrasolecular vibration in the bnckminnterfullerene C_(60),a linear relationship of the superconducting transition temperature T_c with x has been derived,which is in agreement with the experimentals, 展开更多
关键词 RB A=k Rb Cs A AN INVESTIGATION ON THE mechanism OF SUPERCONDUCTIVITY IN ALkALI-DOPED BUCkMINSTERFULLERENE A3C
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Elucidation of the hepatoprotective effect and mechanism of Melastoma dodecandrum Lour. based on network pharmacology and experimental validation
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作者 Jinfeng Wang Linyuan Wang +4 位作者 Zhihao Zhang Min Wu Wenting Fei Zhihui Yang Jianjun Zhang 《Journal of Traditional Chinese Medical Sciences》 2022年第1期47-58,共12页
Objective:To systematically explore the effect and mechanism of melastomatis dodecandri herba(Melastoma dodecandrum Lour.)in the treatment of hepatitis based on network pharmacology.Method:We evaluated the hepatoprote... Objective:To systematically explore the effect and mechanism of melastomatis dodecandri herba(Melastoma dodecandrum Lour.)in the treatment of hepatitis based on network pharmacology.Method:We evaluated the hepatoprotective effects of M.dodecandrum in concanavalin A(Con A)-induced hepatitis in mice by assessing survival rate,histological analysis,serum transaminases,and related cytokines.Then the mechanism of action was predicted by a network pharmacology-based strategy.Based on the results,we measured the hepatic expression of related genes at mRNA level and proteins related to the phosphoinositide 3-kinase(PI3K)/protein kinase B(Akt)and nuclear factorkappa B(NF-кB)pathways.Results:Our study results clearly demonstrated that M.dodecandrum pretreatment significantly alleviated liver injury.This was demonstrated by an increase in survival rate,decreased severity of liver damage,and reduced serum transaminase levels compared with those in the Con A group.Moreover,M.dodecandrum significantly reduced the serum levels of tumor necrosis factor-a,interleukin-6,and interferon-g and increased the liver levels of superoxide dismutase,which indicated that M.dodecandrum exhibits anti-inflammatory and antioxidant activities.On the basis of network pharmacology,50 nodes were selected as major hubs based on their topological importance.Pathway enrichment analyses indicated that the putative targets of M.dodecandrum mostly participate in various pathways associated with the anti-inflammation response,which implies the underlying mechanism by which M.dodecandrum acts on hepatitis.Real-time fluorescent quantitative PCR analysis showed that M.dodecandrum downregulates the mRNA expression of interleukin-6,Toll-like receptor 7,interleukin-1 receptor-associated kinase-4,NF-кB and tumor necrosis factor-a in liver tissues.Western blotting showed that M.dodecandrum pretreatment protected against inflammation through activating the PI3K-Akt pathway by upregulating phosphorylated Akt(p-Akt)expression and suppressing NF-кB activation by inhibiting the phosphorylation of IKK,IkBa,and p65.Conclusion:The present work demonstrated the hepatoprotective effects of M.dodecandrum by regulating the PI3K/Akt and NF-кB pathways in Con A-induced mice,which provide insights into the treatment of hepatitis using M.dodecandrum. 展开更多
关键词 Melastoma dodecandrum Lour. Concanavalin A HEPATITIS Network pharmacology Inflammation mechanism Phosphoinositide 3-kinase(PI3k)/protein kinase B Nuclear factor-kappa B
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Influence of anisotropy on the electrical conductivity and diffusion coefficient of dry K-feldspar: Implications of the mechanism of conduction
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作者 代立东 胡海英 +2 位作者 李和平 孙文清 蒋建军 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期630-639,共10页
The electrical conductivities of single-crystal K-feldspar along three different crystallographic directions are investigated by the Solartron-1260 Impedance/Gain-phase analyzer at 873 K–1223 K and 1.0 GPa–3.0 GPa i... The electrical conductivities of single-crystal K-feldspar along three different crystallographic directions are investigated by the Solartron-1260 Impedance/Gain-phase analyzer at 873 K–1223 K and 1.0 GPa–3.0 GPa in a frequency range of 10-1 Hz–106 Hz. The measured electrical conductivity along the ⊥ [001] axis direction decreases with increasing pressure, and the activation energy and activation volume of charge carriers are determined to be 1.04 ± 0.06 e V and 2.51 ± 0.19 cm~3/mole, respectively. The electrical conductivity of K-feldspar is highly anisotropic, and its value along the⊥ [001] axis is approximately three times higher than that along the ⊥ [100] axis. At 2.0 GPa, the diffusion coefficient of ionic potassium is obtained from the electrical conductivity data using the Nernst–Einstein equation. The measured electrical conductivity and calculated diffusion coefficient of potassium suggest that the main conduction mechanism is of ionic conduction, therefore the dominant charge carrier is transferred between normal lattice potassium positions and adjacent interstitial sites along the thermally activated electric field. 展开更多
关键词 electrical conductivity and diffusion coefficient k-feldspar anisotropy conduction mechanism
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Relationship between microstructure and mechanical properties of undercooled K4169 superalloy 被引量:4
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作者 张可人 谢发勤 +1 位作者 胡锐 吴向清 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1885-1891,共7页
Various undercoolings 14-232 K of bulk K4169 superalloys were obtained by the method of molten glass fluxing combined with superheating cycling and the mechanical properties of undercooled K4169 with as-solidified sta... Various undercoolings 14-232 K of bulk K4169 superalloys were obtained by the method of molten glass fluxing combined with superheating cycling and the mechanical properties of undercooled K4169 with as-solidified state were tested. Microstructures and phases composition in undercooled bulk K4169 superalloy were identified by transmission electron microscope (TEM), scanning electron microscope (SEM) and optical microscopy (OM). The morphology of dendrites, grain size and intergranular phase all change with the increased undercooling. Meanwhile, the relationship between microstructure of undercooled K4169 superalloy and tensile properties was investigated. The experimental results show that the uniform distribution of Laves phase and the decrease of grain size and intergranular phase content are favorable for the improvement of mechanical properties. The maximum tensile strength and elongation obtained at undercooling of 232 K are 932.2 MPa and 6.5%, respectively. 展开更多
关键词 k4169 superalloy UNDERCOOLING Laves phase mechanical properties MICROSTRUCTURES
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基于K-Means聚类与熵权TOPSIS法的岩石可爆性评价研究
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作者 叶海旺 雷丙响 +5 位作者 周汉红 余梦豪 雷涛 王其洲 李宁 Doumbouya Sekou 《爆破》 CSCD 北大核心 2024年第2期112-119,共8页
露天矿山的爆破块度分布,直接影响到后续的采装、运输和破碎工作。为了控制石墨矿山不同区域爆破块度分布,基于K-means无监督聚类学习法与熵权TOPSIS评价法建立了一种新的岩石可爆性评价模型,选取岩石密度、动力能量耗散率、动态抗压强... 露天矿山的爆破块度分布,直接影响到后续的采装、运输和破碎工作。为了控制石墨矿山不同区域爆破块度分布,基于K-means无监督聚类学习法与熵权TOPSIS评价法建立了一种新的岩石可爆性评价模型,选取岩石密度、动力能量耗散率、动态抗压强度、平均应变率、脆性指数作为评价指标,通过熵权计算,发现岩石破碎程度受脆性指数影响最大,受平均应变率影响最小。将此模型应用于实际石墨矿山,可爆性分为10个等级,统计不同分级下的岩石平均破碎粒径,发现可爆性分级等级越高平均粒径越大,有明显的分级特征,验证了模型的有效性。从爆破石墨矿石岩体类型看,岩石可爆性从易到难排序为:片岩、片麻岩、变粒岩、混合岩。结合石墨矿石微观观测结果分析可知:岩性从片岩向混合岩转变,岩石内部石墨晶质呈下降趋势,石墨矿石可爆性等级也随之越来越高。岩石密度、能量耗散率、动态抗压强度之间呈线性正相关,岩石可爆性与平均应变率、脆性指数存在负相关性。研究成果为矿山矿岩可爆性评价提供了一条新思路,对露天矿山爆破块度优化具有一定的理论和实践指导意义。 展开更多
关键词 岩体爆破 可爆性评价 岩石力学 k-MEANS算法 熵权TOPSIS评价
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基于自注意力机制和改进的K-BiLSTM的水产养殖水体溶解氧含量预测模型
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作者 冯国富 卢胜涛 +1 位作者 陈明 王耀辉 《江苏农业学报》 CSCD 北大核心 2024年第3期490-499,共10页
为精确预测水产养殖水体溶解氧含量,本研究提出一种基于自注意力机制(ATTN)和改进的K-means聚类-基于残差和批标准化(BN)的双向长短期记忆网络(BiLSTM)的水产养殖水体溶解氧含量预测模型。首先,根据环境数据的相似性,使用改进的K-means... 为精确预测水产养殖水体溶解氧含量,本研究提出一种基于自注意力机制(ATTN)和改进的K-means聚类-基于残差和批标准化(BN)的双向长短期记忆网络(BiLSTM)的水产养殖水体溶解氧含量预测模型。首先,根据环境数据的相似性,使用改进的K-means算法将数据划分成若干个类别;然后,在BiLSTM基础上构建残差连接和加入BN完成高层次特征提取,利用BiLSTM的长期记忆能力保存特征信息;最后,引入自注意力机制突出不同时间节点数据特征的重要性,进一步提升模型的性能。试验结果表明,本研究提出的基于自注意力机制和改进的K-BiLSTM模型的平均绝对误差为0.238、均方根误差为0.322、平均绝对百分比误差为0.035,与单一的BP模型、CNN-LSTM模型、传统的K-means-基于残差和BN的BiLSTM-ATTN等模型相比具有更优的预测性能和泛化能力。 展开更多
关键词 水产养殖 溶解氧预测 k-MEANS聚类 双向长短期记忆网络(BiLSTM) 自注意力机制
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Microstructure and mechanical properties of NZ30K alloy by semi-continuous direct chill and sand mould casting processes 被引量:25
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作者 Zheng Xingwei Dong Jie +1 位作者 Liu Wencai Ding Wenjiang 《China Foundry》 SCIE CAS 2011年第1期41-46,共6页
The Mg-3.0Nd-0.2Zn-0.4Zr (NZ30K) alloys were prepared by direct-chill casting (DCC) and sand mould casting (SMC) processes,respectively and their microstructures and mechanical properties were investigated.The results... The Mg-3.0Nd-0.2Zn-0.4Zr (NZ30K) alloys were prepared by direct-chill casting (DCC) and sand mould casting (SMC) processes,respectively and their microstructures and mechanical properties were investigated.The results indicate that casting method plays a remarkable influence on the microstructure and mechanical properties of as-cast NZ30K alloy.The grain size increases from 35-40μm in the billets made by the DCC to about 100-120μm in the billets by the SMC.The aggregation of Mg12Nd usually found at the triple joints of grain boundaries in the billets prepared by SMC while is not observable from the billets by DCC.The tensile strengths and elongations of the billets are 195.2 MPa and 15.5% by DCC,and 162.5 MPa and 3.2% by SMC,respectively.The tensile strength of the alloy by DCC is remarkably enhanced by T6 heat treatment,which reached 308.5 MPa.Fracture surfaces of NZ30K alloy have been characterized as intergranular fracture by SMC and quasi-cleavage fracture by DCC,respectively. 展开更多
关键词 NZ30k alloy direct-chill casting MICROSTRUCTURE mechanical properties
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PI3K/AKT/mTOR信号通路在多发性骨髓瘤中作用机制的研究进展 被引量:3
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作者 刘青青 李宜蔷 程纬民 《中国实验血液学杂志》 CSCD 北大核心 2024年第1期292-296,共5页
PI3K/AKT/mTOR信号通路在肿瘤的发生发展、转归预后中具有重要的意义,与多发性骨髓瘤(MM)的发病密切相关。PI3K/AKT/mTOR信号通路可通过多途径、多靶点参与调节MM,如调控MM细胞生存的肿瘤微环境,影响肿瘤发展、迁移,调控MM细胞增殖、凋... PI3K/AKT/mTOR信号通路在肿瘤的发生发展、转归预后中具有重要的意义,与多发性骨髓瘤(MM)的发病密切相关。PI3K/AKT/mTOR信号通路可通过多途径、多靶点参与调节MM,如调控MM细胞生存的肿瘤微环境,影响肿瘤发展、迁移,调控MM细胞增殖、凋亡、自噬。研究表明,PI3K/AKT/mTOR信号通路被抑制后,MM细胞的凋亡、自噬被激活,促进MM细胞的死亡,抑制MM细胞的转移及复发。因此,深入研究PI3K/AKT/mTOR信号通路在MM中的作用机制有助于阐明MM的发病机理及转归预后。 展开更多
关键词 PI3k/AkT/MTOR 多发性骨髓瘤 作用机制
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基于k-means的动态多组织PBFT算法
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作者 杨雨浓 唐凌翔 王洪 《重庆大学学报》 CAS CSCD 北大核心 2024年第7期125-139,共15页
联盟区块链系统被广泛用于金融和物流等场景。现有应用于区块链系统的实用拜占庭算法(practical Byzantine fault tolerance,PBFT)存在可扩展性较低及通信成本较高等问题,阻碍了区块链系统在大规模场景中的应用。针对上述问题,提出了一... 联盟区块链系统被广泛用于金融和物流等场景。现有应用于区块链系统的实用拜占庭算法(practical Byzantine fault tolerance,PBFT)存在可扩展性较低及通信成本较高等问题,阻碍了区块链系统在大规模场景中的应用。针对上述问题,提出了一种动态多组织实用拜占庭容错算法(k-means-practical Byzantine fault tolerance,k-PBFT)。通过改进k-means算法,根据节点的时延以及节点间通信距离将节点分为多个自治组织,各组织之间通过组织代表节点进行通信。当新节点加入时,根据其特点将其分配到最合理的组织。同时,引入信誉机制以辨别系统中的诚实节点与恶意节点,从而提高系统的安全性。此外,该算法还引入节点任期机制,使区块链中每个诚实节点都有机会充当组织代表节点或主节点。实验结果表明,与PBFT算法相比,k-PBFT算法通信复杂度降低了75%;当节点数为100时,相比于PBFT算法,时延降低了210 ms,吞吐量提高了100%。在高延迟环境下,相较于基于信誉分组的PBFT改进算法,当节点数为100时,时延降低了20%,吞吐量提高了17%。 展开更多
关键词 区块链 拜占庭容错算法 k-MEANS算法 信誉机制 节点任期机制
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Influence of roughness on the detection of mechanical characteristics of low-k film by the surface acoustic waves
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作者 肖夏 陶冶 孙远 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期424-428,共5页
The surface acoustic wave (SAW) technique is a precise and nondestructive method to detect the mechanical charac- teristics of the thin low dielectric constant (low-k) film by matching the theoretical dispersion c... The surface acoustic wave (SAW) technique is a precise and nondestructive method to detect the mechanical charac- teristics of the thin low dielectric constant (low-k) film by matching the theoretical dispersion curve with the experimental dispersion curve. In this paper, the influence of sample roughness on the precision of SAW mechanical detection is inves- tigated in detail. Random roughness values at the surface of low-k film and at the interface between this low-k film and the substrate are obtained by the Monte Carlo method. The dispersive characteristic of SAW on the layered structure with rough surface and rough interface is modeled by numerical simulation of finite element method. The Young's moduli of the Black DiamondTM samples with different roughness values are determined by SAWs in the experiment. The results show that the influence of sample roughness is very small when the root-mean-square (RMS) of roughness is smaller than 50 nm and correlation length is smaller than 20 μm. This study indicates that the SAW technique is reliable and precise in the nondestructive mechanical detection for low-k films. 展开更多
关键词 low-k film mechanical character detection rough surface rough interface surface acoustic wave
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基于改进K-means的AODV路由协议
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作者 陈成鹏 查文文 +3 位作者 潘伟豪 汤先美 辜丽川 许正荣 《合肥学院学报(综合版)》 2024年第2期83-90,共8页
AODV路由协议是无线自组织网络中的经典协议,被广泛应用于各种通讯场景中。传统的AODV路由协议在路由发现阶段使用广播方法转发RREQ(路由请求分组),容易造成广播风暴从而影响网络性能。针对该问题,研究提出了基于改进K-means的AODV路由... AODV路由协议是无线自组织网络中的经典协议,被广泛应用于各种通讯场景中。传统的AODV路由协议在路由发现阶段使用广播方法转发RREQ(路由请求分组),容易造成广播风暴从而影响网络性能。针对该问题,研究提出了基于改进K-means的AODV路由协议,使用节点间距离、传输错误数和路由拥塞度作为路由度量,利用密集度参数改进初始聚类中心的选择,设计AODV-K路由协议选择最佳转发节点以减少不必要的路由请求分组转发,提高了路由请求分组的转发效率并减少了路由拥塞。运用NS-3对协议进行仿真,仿真结果表明所提出的改进路由协议,在高网络负载和网络密度下,对比原AODV路由协议,在平均端到端延迟方面分别降低了26.1%和25.6%。当节点数在30、40、50时,在分组投递率方面平均提升13.7%,当每秒发送分组数据包数大于30时,分组投递率平均提高了11.3%。 展开更多
关键词 无线自组织网络 AODV路由协议 路由度量 k-MEANS聚类 消息转发机制
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BFe10-1-1合金K-TIG焊接接头的组织和性能
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作者 马照伟 刘甲 +4 位作者 崔永杰 董闯闯 张亚龙 郁炎 胡伟民 《热加工工艺》 北大核心 2024年第15期112-114,120,共4页
采用Keyhole TIG(K-TIG)焊接工艺开展了10 mm厚BFe10-1-1铜合金板的焊接试验。结果表明:采用K-TIG焊实现了单面焊双面成型,焊缝成型美观,接头焊缝截面无气孔、未熔合、裂纹等缺陷;焊缝区主要为枝晶状α组织,由熔合线向焊缝中心生长延伸... 采用Keyhole TIG(K-TIG)焊接工艺开展了10 mm厚BFe10-1-1铜合金板的焊接试验。结果表明:采用K-TIG焊实现了单面焊双面成型,焊缝成型美观,接头焊缝截面无气孔、未熔合、裂纹等缺陷;焊缝区主要为枝晶状α组织,由熔合线向焊缝中心生长延伸;母材区和热影响区的组织是孪晶状的α相,且热影响区距离焊缝越近,其晶粒尺寸越大。焊缝区的硬度值较高,从焊缝到母材的硬度值先降低再增加,近熔合线的焊缝区和打底焊缝上部区域出现轻微软化。接头平均抗拉强度为346.5 MPa,断裂位置为母材;在α=180°、d=4 t条件下进行侧弯测试,未发现裂纹。 展开更多
关键词 BFe10-1-1合金 k-TIG焊 微观组织 力学性能 硬度
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基于k-modes聚类算法的混洗差分隐私方法
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作者 祁富 陈丽敏 《牡丹江师范学院学报(自然科学版)》 2024年第2期6-13,共8页
首次提出一种基于k-modes聚类算法的混洗差分隐私保护方案(简称SDPk-modes).SDPk-modes根据每个数据之间的距离划分为不同的组,得到足够的细粒度优化效用,采用基于梯度随机扰动技术使计算最优概率耗时更短;在k-modes聚类过程中,通过将... 首次提出一种基于k-modes聚类算法的混洗差分隐私保护方案(简称SDPk-modes).SDPk-modes根据每个数据之间的距离划分为不同的组,得到足够的细粒度优化效用,采用基于梯度随机扰动技术使计算最优概率耗时更短;在k-modes聚类过程中,通过将数据中频繁出现的特征向量作为聚类中心点,基于属性熵的距离度量方法,加快算法收敛至聚类中心的速度,解决原始算法聚类速度慢、易陷入局部最优等问题,显著提高聚类的效果.实验验证表明,本文提出的方案优于当前同类方案. 展开更多
关键词 混洗差分隐私 k-modes 随机响应机制 隐私保护
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植物K^+吸收转运的分子机制研究进展 被引量:12
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作者 鲁黎明 杨铁钊 《棉花学报》 CSCD 北大核心 2006年第6期379-385,共7页
K+在植物的生命活动中发挥着十分重要的作用。植物对K+的吸收,可分为高亲和吸收与低亲和吸收两个组分。在分子水平上,高亲和吸收主要由KUP/HAK/KT及HKT家族的K+转运蛋白来承担;而Shaker、KCO等家族的K+通道蛋白,则主要在植物的低亲和吸... K+在植物的生命活动中发挥着十分重要的作用。植物对K+的吸收,可分为高亲和吸收与低亲和吸收两个组分。在分子水平上,高亲和吸收主要由KUP/HAK/KT及HKT家族的K+转运蛋白来承担;而Shaker、KCO等家族的K+通道蛋白,则主要在植物的低亲和吸收中发挥重要作用。在高等植物K+吸收转运的分子机制的研究中,KAT1及AKT1是两个最先克隆出来的K+通道基因。植物中最先克隆出来的高亲和K+转运体基因,是小麦的HKT1。在棉花的生长发育过程中,K+的作用十分关键。棉花的K+转运蛋白GhKT1在棉纤维的发育中至关重要。综述了高等植物K+吸收运转及调节的分子机制研究方面的最新进展,并对研究的前景进行了展望。 展开更多
关键词 k^-转运体 k^-通道 Shaker家族 分子机制 进展
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Si、Al、K掺杂钼丝的组织和性能研究 被引量:9
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作者 高家诚 王勇 +2 位作者 陈功明 李伟勤 周永贵 《粉末冶金技术》 EI CAS CSCD 北大核心 2007年第1期7-12,16,共7页
通过透射电镜(TEM)、扫描电镜(SEM)、能谱分析(EDS)对Si、Al、K掺杂烧结钼条和退火钼丝的组织形貌进行了跟踪检测分析;通过DSC和硬度试验检测Si、Al、K掺杂钼丝的再结晶温度;通过热模拟试验对纯钼条和Si、Al、K掺杂钼条的高温综合力学... 通过透射电镜(TEM)、扫描电镜(SEM)、能谱分析(EDS)对Si、Al、K掺杂烧结钼条和退火钼丝的组织形貌进行了跟踪检测分析;通过DSC和硬度试验检测Si、Al、K掺杂钼丝的再结晶温度;通过热模拟试验对纯钼条和Si、Al、K掺杂钼条的高温综合力学性能进行了对比分析。结果表明:Si、Al、K掺杂使钼条的高温综合力学性能得到了明显的改善;在本试验条件下,Si、Al、K掺杂使钼丝的再结晶温度提高约550~600℃,再结晶后由长径比大的晶粒形成燕尾搭接状链锁结构组织;Si、Al、K掺杂钼丝的强化相是K泡和硅酸铝钾颗粒。 展开更多
关键词 SI AL k掺杂 钼丝 再结晶温度 k 高温力学性能
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Bain对应和K-S模型的数学描述 被引量:4
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作者 王宝奇 谷南驹 +1 位作者 郭素珍 马晓莉 《金属学报》 SCIE EI CAS CSCD 北大核心 2002年第5期474-478,共5页
利用Bain点阵对应时K-S模型的晶格改建过程进行了严密的数学描述,对于不同的马氏体正方度,提出了计算第一切变、第二切变及晶格调整的计算依据,并给出了普遍的计算公式,以Fe-1.4C和纯铁为例,计算了马氏体相变的点阵畸变,进一步分析表明,... 利用Bain点阵对应时K-S模型的晶格改建过程进行了严密的数学描述,对于不同的马氏体正方度,提出了计算第一切变、第二切变及晶格调整的计算依据,并给出了普遍的计算公式,以Fe-1.4C和纯铁为例,计算了马氏体相变的点阵畸变,进一步分析表明,K-S模型实质是Bain模型的旋转,计算的结果与实测的取向关系相符合。 展开更多
关键词 k-S模型 数学描述 马氏体相变 点阵畸变 Bain模型
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面向复杂系统的知识发现过程模型KD(D&K)及其应用 被引量:10
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作者 杨炳儒 李晋宏 +1 位作者 宋威 李欣 《自动化学报》 EI CSCD 北大核心 2007年第2期151-155,共5页
为适麻复杂系统的知识发现的需要,在双库协同机制及其诱导的KDD过程模型,双基融合机制及其诱导的KDK过程模型的基础上,借鉴协同原理,提出了将KDD与KDK有机地融合在一起的、双库协同机制与双基融合机制协同工作的知识发现过程模型KD(D&am... 为适麻复杂系统的知识发现的需要,在双库协同机制及其诱导的KDD过程模型,双基融合机制及其诱导的KDK过程模型的基础上,借鉴协同原理,提出了将KDD与KDK有机地融合在一起的、双库协同机制与双基融合机制协同工作的知识发现过程模型KD(D&K);描述了KD(D&K)的总体流程、动态知识库系统及其特征;并在农业施肥和植保领域的应用过程中得到验证. 展开更多
关键词 知识发现 双库协同机制 双基融合机制 kD(D&k)
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差分隐私保护下一种精确挖掘top-k频繁模式方法 被引量:29
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作者 张啸剑 王淼 孟小峰 《计算机研究与发展》 EI CSCD 北大核心 2014年第1期104-114,共11页
频繁模式挖掘是分析事务数据集常用技术.然而,当事务数据集含有敏感数据时(如用户行为记录、电子病例等),直接发布频繁模式及其支持度计数会给个人隐私带来相当大的风险.对此提出了一种满足ε-差分隐私的top-k频繁模式挖掘算法DP-topkP(... 频繁模式挖掘是分析事务数据集常用技术.然而,当事务数据集含有敏感数据时(如用户行为记录、电子病例等),直接发布频繁模式及其支持度计数会给个人隐私带来相当大的风险.对此提出了一种满足ε-差分隐私的top-k频繁模式挖掘算法DP-topkP(differentially private top-kpattern mining).该算法利用指数机制从候选频繁模式集合中挑选出top-k个携带真实支持度计数的模式;采用拉普拉斯机制产生的噪音扰动所选模式的真实支持度计数;为了增强输出模式的可用性,采用后置处理技术对top-k个模式的噪音支持度计数进行求精处理.从理论角度证明了该算法满足ε-差分隐私,并符合(λ,δ)-useful要求.实验结果证明了DP-topkP算法具有较好的准确性、可用性和可扩展性. 展开更多
关键词 频繁模式挖掘 top-k模式 差分隐私 拉普拉斯机制 指数机制
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