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Transformations of phosphatidylinositol phosphates in the outer and inner nuclear membrane are linked to synthesis and restitution of cellular membranes 被引量:5
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作者 Amalia Slomiany Bronislaw L. Slomiany 《Health》 2011年第4期187-199,共13页
The ultimate goal in phosphoinositides cellular metabolism is to decipher their global functional organization and coordination of the com- partmentalized signaling processes. In this report we present evidence linkin... The ultimate goal in phosphoinositides cellular metabolism is to decipher their global functional organization and coordination of the com- partmentalized signaling processes. In this report we present evidence linking nuclear phos- phoinositides cycle with endoplasmic reticulum synthesis and function. The rapid transformation of [3H]inositol-labeled phosphoinositides in the intact nuclei (IN) was captured in chase studies for 0-5 min, followed by examination of phosphatidylinositides in the inner nuclear me- mbrane (INM), the outer nuclear membrane (ONM) and endoplasmic reticulum (ER). We revealed that synthesis of phosphatidylinositol phosphates (PIPs) occurs in ONM and the de- phosphorylation takes place in the INM. The rapid transformation of the radiolabeled PIPs in ONM reverberated in their appearance and successive transformation in INM, and in the 5min chased nuclei was tracked to ONM as the re- emerging radiolabeled phosphatidylinositol (PI). These chase-uncovered changes in ONM and INM PIPs profiles allow us to conclude that the observed conversions in the nuclear membrane continuum are induced by the lateral movement of the membrane and its transit from the cytosolic to nuclear and back to cytosolic environment. The suggested membrane synthesisinduced movement provides the means to transport the membrane- and the membrane lipid ligand-associated cytosolic proteins to the intranuclear spaces and renewal of INM. Export of the nuclear components interacting with the modified INM, by exiting from nuclear to cytosolic site, endows ER with a steady influx of the membrane that is conditioned to generate vesicles according to the nucleus delivered templates. 展开更多
关键词 Phosphatidylinositides PIPs Transformation RESTITUTION outer NUCLEAR MEMBRANE inner NUCLEAR MEMBRANE Endoplasmic Reticulum CELLULAR Membranes
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Lipophilic extractives of the inner and outer barks from six different Pinus species grown in Indonesia 被引量:2
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作者 Masendra Tatsuya Ashitani +1 位作者 Koetsu Takahashi Ganis Lukmandaru 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1329-1336,共8页
The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated... The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated by GC and GC–MS.Generally,the amounts of extractive contents were higher in the inner bark than in the outer bark except for P.merksuii.Fatty acids,monoterpenes,sesquiterpenes,resin acids,triterpenoids,and steroids were detected and quantified.Inner and outer barks differed not only in content of these compounds but also in their composition.Fatty acids and alcohols were the major classes of lipophilic compounds in the outer bark of P.caribeae, P.insularis,and P.montezumae.Steroids and triterpenoids were the dominant compounds identified in the inner bark of P.elliotii,P.insularis,and P.merkusii.Resin acids were the most abundant group in the inner bark of P.oocarpa whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species. 展开更多
关键词 Bark extractive LIPOPHILIC inner bark outer bark Pinus spp
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Petrogenesis of Early Permian Intrusive Rocks from Southeastern Inner Mongolia, China: Constraints on the Tectonic Framework of the Southeastern Central Asian Orogenic Belt 被引量:2
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作者 QIAN Cheng LU Lu +4 位作者 SHI Lu DU Jiyu WANG Yan YANG Xiaoping ZHANG Yujin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第5期1566-1586,共21页
The late Paleozoic tectonic framework of the southeastern Central Asian Orogenic Belt is key to restricting the accretion orogeny between the Siberia Craton and the North China Craton. To clarify the framework, petrog... The late Paleozoic tectonic framework of the southeastern Central Asian Orogenic Belt is key to restricting the accretion orogeny between the Siberia Craton and the North China Craton. To clarify the framework, petrogenesis of early Permian intrusive rocks from southeastern Inner Mongolia was studied. Zircon U-Pb dating for bojite and syenogranite from Ar-Horqin indicate that they were emplaced at 288–285 Ma. Geochemical data reveal that the bojite is highly magnesian and low-K to middle-K calc-alkaline, with E-MORB-type REE and IAB-like trace element patterns. The syenogranite is a middle-K calc-alkaline fractionated A-type granite and shows oceanic-arc-like trace element patterns, with depleted Sr-Nd-Hf isotopes,(~(87)Sr/~(86)Sr)I = 0.7032–0.7042, ε_(Nd)(t) = +4.0 to +6.6 and zircon ε_(Hf)(t) = +11.14 to +14.99. This suggests that the bojite was derived from lithospheric mantle metasomatized by subducted slab melt, while the syenogranite originated from very juvenile arc-related lower crust. Usng data from coeval magmatic rocks from Linxi-Ar-Horqin, the Ar-Horqin intra-oceanic arc was reconstructed, i.e., initial transition in 290–280 Ma and mature after 278 Ma. Combined with regional geological and geophysical materials in southeastern Inner Mongolia, an early Permian tectonic framework as ‘one narrow ocean basin of the PAO', ‘two continental marginal arcs on its northern and southern' and ‘one intra-oceanic arc in its southern' is proposed. 展开更多
关键词 tectonic framework early Permian intra-oceanic arc southeastern inner Mongolia Central Asian Orogenic Belt
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Viscous Inner and Outer Pressure Forming Method of Thin-walled Tube and Its Application 被引量:3
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作者 高铁军 LIU Yang WANG Zhongjin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第2期404-407,共4页
Aiming at overcoming the difficulties in integral forming of thin-walled tubes with complex shapes, a novel forming method by inner and outer pressure through viscous was proposed. In this method, by dividing large de... Aiming at overcoming the difficulties in integral forming of thin-walled tubes with complex shapes, a novel forming method by inner and outer pressure through viscous was proposed. In this method, by dividing large deformation of the part into inner and outer pressure forming deformations, the limit deformation of tube part can be increased by several times. Meanwhile, the principle of viscous inner and outer pressure forming was provided, and key problems during the forming process such as reduction of the wall-thickness and instability wrinkling were analyzed. Thereby, the complex curved surface super-alloy GH3044 thin-walled tube with varying diameter ratio of 1.35(the ratio between the maximum and minimum diameters of the part) can be integrally formed by this method. The experimental surface of the formed part is superior in quality and the wall-thickness distribution is uniform. The results show that the viscous inner and outer pressure forming can provide a new approach for integral forming of thin-walled tubes with complex shapes. 展开更多
关键词 thin-walled tube inner and outer pressure forming viscous medium integral forming
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Influence of Inner/Outer Stator Pole Ratio and Relative Position on Electromagnetic Performance of Partitioned Stator Switched Flux Permanent Magnet Machines 被引量:1
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作者 J.T.Shi Z.Q.Zhu 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第3期259-268,共10页
Based on the 6-pole outer stator(armature winding-stator),the influence of inner(permanent magnet-stator)/outer stator pole ratio n(n=NIS/NOS),stator relative positions and rotor pole number combinations on electromag... Based on the 6-pole outer stator(armature winding-stator),the influence of inner(permanent magnet-stator)/outer stator pole ratio n(n=NIS/NOS),stator relative positions and rotor pole number combinations on electromagnetic performance of partitioned stator switched flux permanent magnet(PM)machines(PS-SFPMMs)is investigated in this paper.Since the armature windings and PMs are located in two separated stators and PMs are stationary,PS-SFPMMs have high fault tolerance capabilities.To maximize the torque performance,the PM of inner stator pole should be aligned with outer stator pole when n is odd while the iron rib of inner stator pole should be aligned with outer stator pole when n is even.No matter what n is selected,the rotor pole number NR can be any integers except the phase number and its multiples.The analysis results indicate that the optimal NR is closed to(NIS+NOS)/2 and it is odd when n is odd while it is even when n is even.Meanwhile,symmetrical phase back-EMF waveform will be obtained when the ratio of Min(NOS,NIS)to the greatest common divisor of Min(NOS,NIS)and NR is even.Based on the optimal rotor pole numbers for 6-pole outer stator with different n and corresponding optimal relative position together with same rated copper loss,the average torque is improved by 18.4%,25.1%and 25.7%respectively in PS-SFPMMs with n equal to 2,3 and 4 when compared with PS-SFPMM with n equal to 1.The analyses are validated by experiment results of the prototype machine. 展开更多
关键词 inner/outer stator partitioned stator permanent magnet pole ratio relative position switched flux.
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Inner and outer pressure forming of nickel based super-alloy thin-walled part with variable diameter sections 被引量:3
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作者 王忠金 高铁军 《中国有色金属学会会刊:英文版》 EI CSCD 2008年第2期285-290,共6页
A novel forming method of nickel based super-alloy thin-walled part with variable diameter sections was proposed by using inner and outer pressure with the visco-elasto-plastic pressure-carrying medium at room tempera... A novel forming method of nickel based super-alloy thin-walled part with variable diameter sections was proposed by using inner and outer pressure with the visco-elasto-plastic pressure-carrying medium at room temperature,and the principle of the method was provided.Experiments and FE simulations were carried out to analyze the deformation characteristics for the part with larger variable diameter ratio(35%).The results show that visco-elasto-plastic pressure-carrying medium can meet the requirements of the room-temperature deformation condition for nickel based super-alloy sheet.The inner and outer pressure forming with the visco-elasto-plastic pressure-carrying medium can meet the requirements of dimensional accuracy for the thin-walled part with variable diameter sections.The thinning of wall-thickness is less than 4%.This method provides a new approach for near-net shape forming of nickel based super-alloy thin-walled parts with variable diameter sections. 展开更多
关键词 压力成型技术 合金 直径 变量
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Synchronization investigation of the network group constituted by the nearest neighbor networks under inner and outer synchronous couplings
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作者 李亭亭 李成仁 +4 位作者 王晨 何芳君 周光冶 孙景昌 韩非 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第12期572-576,共5页
A new synchronization technique of inner and outer couplings is proposed in this work to investigate the synchro- nization of network group. Some Haken-Lorenz lasers with chaos behaviors are taken as the nodes to cons... A new synchronization technique of inner and outer couplings is proposed in this work to investigate the synchro- nization of network group. Some Haken-Lorenz lasers with chaos behaviors are taken as the nodes to construct a few nearest neighbor complex networks and those sub-networks are also connected to form a network group. The effective node controllers are designed based on Lyapunov function and the complete synchronization among the sub-networks is realized perfectly under inner and outer couplings. The work is of potential applications in the cooperation output of lasers and the communication network. 展开更多
关键词 synchronization of network group inner and outer couplings Haken-Lorenz laser nearest neigh-bor network
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Performance evaluations on inner vs. outer decomposition first parallel join algorithms for two nested loop joins
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作者 Seo-Young NOH Heejun YOON +2 位作者 Il-Yeon YEO Yoon-su JEONG Hyungwoo PARK 《Journal of Central South University》 SCIE EI CAS 2014年第10期3873-3882,共10页
Two popular traditional join algorithms and their parallel versions are introduced. When designing join algorithms in serial computing environment, decomposing inner relation is considered as the right direction to sa... Two popular traditional join algorithms and their parallel versions are introduced. When designing join algorithms in serial computing environment, decomposing inner relation is considered as the right direction to save disk I/Os. However, two different decomposition algorithms are compared, such as inner vs. outer decomposition first algorithms for tuple-based and block-based nested loop joins, showing that the proposed approach is 20% better than general approach. Also lemmas are proved, when we have to use the outer decomposition first parallel join algorithms. 展开更多
关键词 parallel join performance inner decomposition outer decomposition
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Forward masking in distinguishing inner and outer hair cell damage
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作者 DUAN Mao-li Department of Clinical Neuroscience,Karolinska Institutet Department of Otorhinolaryngology Head and Neck & Center for Hearing and Communication Research,Karolinska University Hospital,Sweden 《Journal of Otology》 2009年第1期23-25,共3页
Forward Masking Temporal audiotory resolution is the ability of the auditory system to resolve auditory signals in the time domain. Forward masking is a means of studying temporal resolution where one tone, the probe,... Forward Masking Temporal audiotory resolution is the ability of the auditory system to resolve auditory signals in the time domain. Forward masking is a means of studying temporal resolution where one tone, the probe, is masked by a preceding tone, the masker. Forward masking is 展开更多
关键词 CELL Forward masking in distinguishing inner and outer hair cell damage ABR
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Malfunction of outer retinal barrier and choroid in the occurrence and progression of diabetic macular edema 被引量:5
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作者 ŞtefanŢălu Simona Delia Nicoara 《World Journal of Diabetes》 SCIE CAS 2021年第4期437-452,共16页
Diabetic macular edema(DME) is the most common cause of vision loss in diabetic retinopathy,affecting 1 in 15 patients with diabetes mellitus(DM).The disruption of the inner blood-retina barrier(BRB) has been largely ... Diabetic macular edema(DME) is the most common cause of vision loss in diabetic retinopathy,affecting 1 in 15 patients with diabetes mellitus(DM).The disruption of the inner blood-retina barrier(BRB) has been largely investigated and attributed the primary role in the pathogenesis and progression in DME, but there is increasing evidence regarding the role of outer BRB, separating the RPE from the underlying choriocapillaris,in the occurrence and evolution of DME.The development of novel imaging technologies has led to major improvement in the field of in vivo structural analysis of the macula allowing us to delve deeper into the pathogenesis of DME and expanding our vision regarding this condition.In this review we gathered the results of studies that investigated specific outer BRB optical coherence tomography parameters in patients with DM with the aim to outline the current status of its role in the pathogenesis and progression of DME and identify new research pathways contributing to the advancement of knowledge in the understanding of this condition. 展开更多
关键词 Diabetic macular edema External limiting membrane Hyperreflective foci inner segment/outer segment line Optical coherence tomography outer retinal barrier
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A Matrix Representation of Outer Derivations from gl0|2 to the Generalized Witt Lie Superalgebra 被引量:1
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作者 ZHENG KE-LI Du Xian-kun 《Communications in Mathematical Research》 CSCD 2019年第4期367-376,共10页
Let gl0|2 be a subalgebra of the general linear Lie superalgebra.In this paper,outer derivations from gl0|2 to the generalized Witt Lie superalgebra are completely determined by matrices.
关键词 outer DERIVATION inner DERIVATION matrix representation generalized Witt LIE SUPERALGEBRA
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内圣外王的期盼:中国古代君德论及其特征 被引量:1
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作者 王记录 刘饶 《河南师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第2期98-107,共10页
中国古代君德论起源于殷周,发展于两汉,兴盛于唐,繁荣于两宋,变革于明末清初,一脉相承而内容不断丰富。君德的内容包含了君主的德性、器识、才智、能力等诸多因素,主要体现在君主个人修养以及施政过程中如何处理君臣关系、君民关系等方... 中国古代君德论起源于殷周,发展于两汉,兴盛于唐,繁荣于两宋,变革于明末清初,一脉相承而内容不断丰富。君德的内容包含了君主的德性、器识、才智、能力等诸多因素,主要体现在君主个人修养以及施政过程中如何处理君臣关系、君民关系等方面。完善君德的方式主要有经筵讲读、皇储教育、家训教化、大臣谏诤、史书褒贬。古代君德论特征鲜明,君主地位的尊崇、历史的教训与现实的需要是君德论的起点,儒家“修齐治平”“内圣外王”理论是君德论的思想基础,读经观史,以经为则、以史为鉴是完善君德的重要手段,“致君尧舜”是君德修养的重点。古人已经形成了一套围绕君主而展开的关于君德修养的理论体系。同时也要看到,古人讨论君德,既存在“师道”与“君道”之间无法调和的矛盾,也没有进行制度层面的反思,反映的只是一种泛道德化的政治伦理观。 展开更多
关键词 君德论 君主修养 帝王学 内圣外王 历史教育
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“内国”与“外土”:周代铜器铭文所见的两个疆域概念 被引量:1
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作者 王坤鹏 《中原文化研究》 2024年第1期120-128,共9页
周代铜器录卣铭中的“内国”及戎生钟铭中的“外土”构成了一对在内涵上密切相关的疆域概念。这两个概念有特定内涵,“内国”意为“内域”,在铭文中指以郑洛地区为中心的中原腹地,这一地区自夏代至两周一直是早期王朝的核心疆域。“外... 周代铜器录卣铭中的“内国”及戎生钟铭中的“外土”构成了一对在内涵上密切相关的疆域概念。这两个概念有特定内涵,“内国”意为“内域”,在铭文中指以郑洛地区为中心的中原腹地,这一地区自夏代至两周一直是早期王朝的核心疆域。“外土”为周王朝领土的外层区域,其地存在着大量的土著族群。不过作为周王朝能够有效管辖的区域,该区仍属周王朝之疆域。“内国”与“外土”作为一对疆域概念,反映了周王朝疆域形态及疆域治理均具有多层次性的特征。“内国”是王朝疆域的内层,由王廷所任命的内服职官加以治理。“外土”则是王朝疆域的外层,周王朝于此广设侯、伯贵族以治理土著族群并威慑在其之外的敌对势力。至于“外土”之外的区域,亦可能受到周人的军事打击,但周王朝已无法对其进行有效控制,其地已非周之疆域。 展开更多
关键词 西周 内国 外土 疆域
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圆柱滚子轴承滚子对数修形优化研究
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作者 吕海霆 郭玉飞 +2 位作者 魏延刚 许凯 姚金池 《机电工程》 CAS 北大核心 2024年第4期604-612,共9页
为了提高轴承的疲劳寿命,采用Romax Designer工程分析软件,在充分考虑径向游隙和内外圈相对倾斜量(影响轴承寿命的主要因素)对修形效果影响的基础上,对某大兆瓦风电机组齿轮箱输出轴轴承进行了对数修形优化分析。首先,对国际标准ISO/TS ... 为了提高轴承的疲劳寿命,采用Romax Designer工程分析软件,在充分考虑径向游隙和内外圈相对倾斜量(影响轴承寿命的主要因素)对修形效果影响的基础上,对某大兆瓦风电机组齿轮箱输出轴轴承进行了对数修形优化分析。首先,对国际标准ISO/TS 16281寿命计算方法进行了简要分析;然后,对不同径向游隙情况下对数修形的效果进行了分析;最后,对不同内外圈相对倾斜量情况下对数修形的效果进行了分析。研究结果表明:以轴承最大接触应力最小为优化目标和以国际标准ISO/TS 16281寿命最长为优化目标的轴承对数修形,其最佳修形量不同,相应的ISO/TS 16281寿命有很大不同;在该轴承的具体条件下,以ISO/TS 16281寿命最长为优化目标的最佳修形凸度量对应的ISO/TS 16281寿命比以最大接触应力最小为优化目标的最佳修形凸度量对应的ISO/TS 16281寿命长2.39%~10.63%;以ISO/TS 16281寿命最长为优化目标的最佳修形凸度量对应的ISO/TS 16281寿命比未修形的ISO/TS 16281寿命长111.47%~1054.88%,建议以ISO/TS 16281寿命最长为优化目标对轴承进行修形优化设计。该研究结果可为滚子类轴承的优化设计提供参考。 展开更多
关键词 滚柱轴承 对数修形 接触应力 疲劳寿命 径向游隙 内外圈相对倾斜量 国际标准ISO/TS 16281
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基于奇异摄动分解的带机械臂旋翼无人机飞行稳定性研究
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作者 梅平 谢双双 +1 位作者 张豪 刘云平 《电光与控制》 CSCD 北大核心 2024年第9期18-24,37,共8页
为了降低无人机和机械臂之间的耦合作用,提高带臂四旋翼无人机飞行过程中的稳定性,首先建立系统动力学模型,然后根据实际情况,对模型进行简化。在此基础上进行内、外环分解,外环为四旋翼位置控制和机械臂角度控制,内环为四旋翼俯仰角控... 为了降低无人机和机械臂之间的耦合作用,提高带臂四旋翼无人机飞行过程中的稳定性,首先建立系统动力学模型,然后根据实际情况,对模型进行简化。在此基础上进行内、外环分解,外环为四旋翼位置控制和机械臂角度控制,内环为四旋翼俯仰角控制。对于外环的动力学模型,根据速度变化特点,利用奇异摄动理论对外环变量,即四旋翼线速度和机械臂角速度,进行快、慢变子系统分解,再次降低了系统间的耦合性。对于分解后的快、慢变子系统,设计非奇异终端滑模控制并引入干扰观测器,以期提高带臂四旋翼无人机飞行过程中的稳定性。最后,仿真验证了所设计算法的优越性。 展开更多
关键词 无人机 机械臂 飞行稳定性 内外环分解 奇异摄动理论 非奇异终端滑模控制
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概率区间值犹豫模糊集多属性群决策模型及其应用
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作者 朱国成 张娟 徐健 《中国计量大学学报》 2024年第1期106-115,共10页
目的:研究概率区间值犹豫模糊集及应用。方法:将概率区间值犹豫模糊数,用区间值隶属度的中位数、区间值隶属度的清晰度以及概率构成的三维点坐标进行刻画,在此基础上提出了概率区间值犹豫模糊元的相关运算。根据概率区间值犹豫模糊元的... 目的:研究概率区间值犹豫模糊集及应用。方法:将概率区间值犹豫模糊数,用区间值隶属度的中位数、区间值隶属度的清晰度以及概率构成的三维点坐标进行刻画,在此基础上提出了概率区间值犹豫模糊元的相关运算。根据概率区间值犹豫模糊元的相关运算采用熵值法计算属性权重。最后基于TOPSIS思想给出了一个新的贴近度公式,并利用新的贴近度公式对方案排序。结果:建立的概率区间值犹豫模糊集多属性群决策模型可以有效排序方案。结论:将概率区间值犹豫模糊集采用区间值隶属度的中位数、区间值隶属度的清晰度以及概率来表示不仅可行,而且可以用来解决多属性群决策问题。 展开更多
关键词 概率区间值犹豫模糊集 三维点坐标 外值函数模型 内值函数模型 TOPSIS
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经世的庄子与庄子的经世——论钟泰对庄子内圣外王之道的开显
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作者 郭敬东 《中国文化与管理》 2024年第1期82-93,271,共13页
历代解庄、注庄者在诠释庄子思想时,多将庄子视为岩穴之士,而忽略了其思想中所具有的经世之志与治理主张。钟泰则通过对《庄子》文本的分析,在梳理庄子形象变迁的基础上,指出了庄子思想中所具有的忧患意识与现实关照。他认为《庄子》内... 历代解庄、注庄者在诠释庄子思想时,多将庄子视为岩穴之士,而忽略了其思想中所具有的经世之志与治理主张。钟泰则通过对《庄子》文本的分析,在梳理庄子形象变迁的基础上,指出了庄子思想中所具有的忧患意识与现实关照。他认为《庄子》内七篇完整地阐发了庄子本人的内圣外王之道:《逍遥游》阐明了内圣外王之道的价值指向,《齐物论》为内圣外王之道奠定了认识论基础,《养生主》指出了内圣外王之道的修养工夫,《人间世》则阐发了内圣外王之道的实践智慧,《德充符》则诠释了内圣外王之道的内在关联,《大宗师》与《应帝王》则论述了内圣外王之道的实施路径。以此内七篇为基础,钟泰分别细致剖析了庄子内圣之学与外王之道的具体含义,彰显了庄子经世思想的内在逻辑,为理解庄子治道思想开显了政治哲学视域下的诠释路径。 展开更多
关键词 钟泰 庄子 内圣外王
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基于内外侧联动式抽芯的多分型面镂空式收纳桶模具设计 被引量:1
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作者 邵俊 胡烈 +1 位作者 褚建忠 任建平 《工程塑料应用》 CAS CSCD 北大核心 2024年第7期109-115,共7页
根据产品的使用性能和工艺特点,对镂空式收纳桶的产品结构和工艺进行了分析。基于产品镂空和桶槽分布位置的不同,设计了3层分型面的模具结构,以实现对各个成型部分的运动控制;镂空形状分布面积比较大,为提高成型质量、节省模具空间,巧... 根据产品的使用性能和工艺特点,对镂空式收纳桶的产品结构和工艺进行了分析。基于产品镂空和桶槽分布位置的不同,设计了3层分型面的模具结构,以实现对各个成型部分的运动控制;镂空形状分布面积比较大,为提高成型质量、节省模具空间,巧妙设计了定模侧爆炸式滑块抽芯机构;由于产品底部的侧凹形状位于定模底部,空间狭窄且缺乏动力源,因此在定模底部设计了型腔侧浮动式斜顶机构,完成了底部侧凹的抽芯动作;针对产品边缘具有内外圆角的大尺寸桶槽,在动模内部设计了内外侧联动式抽芯机构。模具投产后,各个抽芯机构动作顺畅,产品脱模顺利,达到了预期目的。 展开更多
关键词 内外侧抽芯 多分型面 爆炸式滑块 浮动式斜顶
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内/外隔热复合结构炸药装药快速烤燃热防护效应 被引量:1
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作者 白孟璟 段卓平 +4 位作者 白志玲 张玉龙 刘瑞峰 张连生 黄风雷 《兵工学报》 EI CAS CSCD 北大核心 2024年第5期1555-1563,共9页
为了研究快速烤燃(火烧)条件下炸药装药内/外隔热复合结构(内隔热材料/外阻燃材料)的热防护效应,对多种内/外隔热复合结构的炸药装药进行多点测温快速烤燃试验,得到火焰场和炸药装药各测点的温度-时间曲线及装药点火响应时间。开展内/... 为了研究快速烤燃(火烧)条件下炸药装药内/外隔热复合结构(内隔热材料/外阻燃材料)的热防护效应,对多种内/外隔热复合结构的炸药装药进行多点测温快速烤燃试验,得到火焰场和炸药装药各测点的温度-时间曲线及装药点火响应时间。开展内/外隔热复合结构炸药装药快速烤燃数值模拟,获得内/外隔热复合结构对装药快速烤燃点火响应时间的影响规律。研究结果表明:在快速烤燃过程中,外阻燃材料由于火烧变性存在导热增强及隔热减弱效应,在数值模拟中需考虑该效应;无论使用单独的隔热/阻燃材料还是使用内/外隔热复合结构,炸药装药的点火响应时间均随着材料涂覆厚度增加而延后,其中内/外隔热复合结构具有更好的热防护能力;点火位置均发生在装药端面棱角处,装药点火后反应烈度不受内/外隔热复合结构影响,反应等级均为爆燃;对于一定热防护性能范围内的隔热阻燃材料,壳体外表面涂层材料是耐高温纳米隔热材料、壳体内表面涂层材料是高效隔热防护材料时复合结构的隔热效果最好,并且当需求的隔热效果给定时,可考虑优先增加壳体外表面涂层的涂覆厚度,实现以最小涂覆厚度的内/外隔热复合结构满足所需的隔热效果。研究成果可为提升弹药热安全性设计提供参考。 展开更多
关键词 炸药装药 快速烤燃 内/外隔热复合结构 热防护效应 点火延迟
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无人驾驶农机装备的模糊PI-LQR转向控制算法 被引量:1
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作者 姬江涛 王启洲 +1 位作者 张玉成 韩志豪 《河南科技大学学报(自然科学版)》 CAS 北大核心 2024年第3期9-16,共8页
无人驾驶农机装备转向系统处于小流量、小角度控制时会出现非线性和时滞,这会导致转向控制超调或者控制时滞,进而导致无法快速准确地跟踪到路径预瞄点。针对这个问题,本文提出了一种模糊比例积分-线性二次型调节器(PI-LQR)数据融合的内... 无人驾驶农机装备转向系统处于小流量、小角度控制时会出现非线性和时滞,这会导致转向控制超调或者控制时滞,进而导致无法快速准确地跟踪到路径预瞄点。针对这个问题,本文提出了一种模糊比例积分-线性二次型调节器(PI-LQR)数据融合的内外环控制算法。该算法以模糊PI控制为内环,基于转角误差和转角误差变化率,通过模糊逻辑运算自适应调节PI参数,进行转向角度的闭环控制。以LQR控制为外环,基于农机装备XY-横摆角控制,融合内环的转角误差,进一步提升无人驾驶农机装备转向的精准控制。Carsim和Matlab/Simulink联合仿真表明:通过100 m长的双移线路径下,最大横向误差为0.18 m,最大横向摆角误差为0.067 rad。实车测试表明:通过100 m长的双移线路径下,最大横向误差0.26 m,相较于PID纯跟踪控制算法,最大横向误差减少了0.19 m。 展开更多
关键词 无人驾驶 转向系统 模糊PI LQR 内外环控制
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