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The Gap Labelling Integrated Density of States for a Quasi Crystal Universe Is Identical to the Observed 4.5 Percent Ordinary Energy Density of the Cosmos 被引量:2
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作者 Mohamed S. El Naschie 《Natural Science》 2014年第16期1259-1265,共7页
Condense matter methods and mathematical models used in solving problems in solid state physics are transformed to high energy quantum cosmology in order to estimate the magnitude of the missing dark energy of the uni... Condense matter methods and mathematical models used in solving problems in solid state physics are transformed to high energy quantum cosmology in order to estimate the magnitude of the missing dark energy of the universe. Looking at the problem from this novel viewpoint was rewarded by a rather unexpected result, namely that the gap labelling method of integrated density of states for three dimensional icosahedral quasicrystals is identical to the previously measured and theoretically concluded ordinary energy density of the universe, namely a mere 4.5 percent of Einstein’s energy density, i.e. E(O) = mc2/22 where E is the energy, m is the mass and c is the speed of light. Consequently we conclude that the missing dark energy density must be E(D) = 1 - E(O) = mc2(21/22) in agreement with all known cosmological measurements and observations. This result could also be interpreted as a strong evidence for the self similarity of the geometry of spacetime, which is an expression of its basic fractal nature. 展开更多
关键词 e-INFINITY Theory Fractal-Witten m-THeORY GAP Labelling Theorem DeNSITY of states Dark energy DeNSITY Noncommutative Geometry K-THeORY Dimension Group
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N—策略M/G/1/∞(E,MV)排队系统的一个递推公式 被引量:1
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作者 魏瑛源 《河西学院学报》 2005年第2期10-12,共3页
在文献[1]的基础上,利用嵌入Markow链和PASTA性质,得到了N-策略M/G/1/∞(E,MV)排队系统在任意时刻队长平稳分布的递推公式.
关键词 N-策略 m/G/1/∞(e mV) 队长 平稳分布
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输入率与服务率依赖状态的M/M/c排队模型 被引量:5
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作者 梁希泉 韩玉群 荆禄旭 《青岛科技大学学报(自然科学版)》 CAS 北大核心 2013年第1期103-106,共4页
针对M/M/c排队服务模型,讨论了c个服务台全部繁忙时系统的输入率与服务率依赖系统状态的问题。当服务台至少有一个空闲时,系统的输入率与服务率均恒定不变;当系统服务台全部繁忙时,输入率与服务率同时变化,假设顾客到达系统并进入系统... 针对M/M/c排队服务模型,讨论了c个服务台全部繁忙时系统的输入率与服务率依赖系统状态的问题。当服务台至少有一个空闲时,系统的输入率与服务率均恒定不变;当系统服务台全部繁忙时,输入率与服务率同时变化,假设顾客到达系统并进入系统接受服务的概率为αk(0≤αk≤1),并且假设系统中每个服务台的服务率会提高βk(≥1)倍。根据假设分析得到系统状态转移图,然后利用平衡方程和正则性证明平稳分布定理,从而得到了顾客的平均输入率、平均服务强度、平均队长、系统顾客损失率等指标。 展开更多
关键词 依赖状态 输入率 服务率 平稳分布 m m c
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肿瘤转移中EMT的作用及其调控网络 被引量:1
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作者 李雅倩 罗新鹏 +1 位作者 李宇轩 赵同军 《生命的化学》 CAS 2024年第1期64-72,共9页
恶性肿瘤的转移是肿瘤细胞通过上皮间质转化(epithelial-mesenchymal transition,EMT)获得间质特性从原发部位向远处转移的过程。转移过程中肿瘤细胞既可能发生完全EMT以单细胞形式转移,也可能发生部分EMT以混合E/M状态的小细胞簇形式转... 恶性肿瘤的转移是肿瘤细胞通过上皮间质转化(epithelial-mesenchymal transition,EMT)获得间质特性从原发部位向远处转移的过程。转移过程中肿瘤细胞既可能发生完全EMT以单细胞形式转移,也可能发生部分EMT以混合E/M状态的小细胞簇形式转移,且混合E/M状态的肿瘤细胞比完全间质状态的肿瘤细胞转移潜力更高。本文对混合E/M状态以及EMT进程在肿瘤转移中的作用等方面的最新研究进展予以综述,讨论了影响肿瘤转移的EMT相关调控网络,分析了针对EMT调控网络来抑制肿瘤转移的治疗策略。这些总结有助于深入理解肿瘤转移中EMT及其调控网络的分子机制,为肿瘤转移与复发等方面的基础实验研究及临床抗肿瘤治疗提供借鉴和参考。 展开更多
关键词 上皮间质转化 肿瘤转移 混合e/m状态 调控网络
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A unified description of shape coexistence and mixed-symmetry states in^98Mo using IBM-2
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作者 Cheng-Fu Mu Da-Li Zhang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第5期65-69,共5页
Level structure and electromagnetic transitions in^98Mo have been investigated on the basis of the proton-neutron interacting boson model(IBM-2)by considering the energy difference between neutron bosonενand proton ... Level structure and electromagnetic transitions in^98Mo have been investigated on the basis of the proton-neutron interacting boson model(IBM-2)by considering the energy difference between neutron bosonενand proton bosonεπ.The results are compared with the recent experimental data and it is observed that they are in good agreement.In particular,the strongest M1 transition from 25^+state to 22^+can be well reproduced,from which one can determine the 25^+as an mixed-symmetry(MS)state.We have calculated the electric monopole strengthρ^2(E0,02^+→01^+),and our result agrees with the experimental one.The calculation indicates that shape coexistence and MS states are simultaneously well described using IBM-2. 展开更多
关键词 shape coexistence mixed-symmetry state IBm-2 e2 and m1 transitions
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Maximizing power saving with state transition overhead for multiple mobile subscriber stations in WiMAX
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作者 Bo LI Sung-kwon PARK 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第10期1085-1094,共10页
In the IEEE 802.16e/m standard, three power saving classes (PSCs) are defined to save the energy of a mobile sub- scriber station (MSS). However, how to set the parameters of PSCs to maximize the power saving and ... In the IEEE 802.16e/m standard, three power saving classes (PSCs) are defined to save the energy of a mobile sub- scriber station (MSS). However, how to set the parameters of PSCs to maximize the power saving and guarantee the quality of service is not specified in the standard. Thus, many algorithms were proposed to set the PSCs in IEEE 802.16 networks. However, most of the proposed algorithms consider only the power saving for a single MSS. In the algorithms designed for multiple MSSs, the sleep state, which is set for activation of state transition overhead power, is not considered. The PSC setting for real-time connections in multiple MSSs with consideration of the state transition overhead is studied. The problem is non-deterministic polynomial time hard (NP-hard), and a suboptimal algorithm for the problem is proposed. Simulation results demonstrate that the energy saving of the proposed algorithm is higher than that of state-of-the-art algorithms and approaches the optimum limit. 展开更多
关键词 Power saving class state transition overhead Ieee 802.16e/m Quality of service
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动静压轴承支承电主轴服役精度保持用磁力减载研究 被引量:7
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作者 陈润霖 欧阳武 +1 位作者 王建磊 袁小阳 《振动与冲击》 EI CSCD 北大核心 2017年第12期25-30,共6页
为了保持动静压轴承支承电主轴的服役精度,提出采用电磁力消减静动态加工力的方案并研制了一套磁力减载系统。以磨床为例,建立电主轴系统的动力学模型,获取了载荷与轴端位移的关系;估算了磨削加工时产生的静态和动态加工力,提出了服役... 为了保持动静压轴承支承电主轴的服役精度,提出采用电磁力消减静动态加工力的方案并研制了一套磁力减载系统。以磨床为例,建立电主轴系统的动力学模型,获取了载荷与轴端位移的关系;估算了磨削加工时产生的静态和动态加工力,提出了服役精度保持的静/动载荷需求;设计并建造了磁力减载系统,包括结构和测控两个模块;其中,结构模块特色在于磁力减载组件配备有万向支撑方案,测控模块支持开环和闭环两种控制策略;设计专项试验验证了减载系统的性能。研究结果表明:不转时减载组件可实现约35 N静载和28 N幅值谐波动载功能,初步证明采用电磁技术消减机床加工力是可行的。针对引入减载装置的电主轴系统,采用人工调节电流的开环控制策略更有效。 展开更多
关键词 动静压轴承 电主轴 磁力减载 精度保持 服役精度
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国产海桑属植物的两个杂交种 被引量:23
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作者 王瑞江 陈忠毅 +1 位作者 陈二英 郑馨仁 《广西植物》 CAS CSCD 北大核心 1999年第3期199-204,共6页
作者通过对红树林海桑属植物进行形态学、花粉学、细胞学以及其它方面的比较研究,证实了拟海桑和海南海桑为两个杂交种,它们的嫌疑亲本分别是杯萼海桑和海桑、杯萼海桑和卵叶海桑·sonneratia×hainanenw... 作者通过对红树林海桑属植物进行形态学、花粉学、细胞学以及其它方面的比较研究,证实了拟海桑和海南海桑为两个杂交种,它们的嫌疑亲本分别是杯萼海桑和海桑、杯萼海桑和卵叶海桑·sonneratia×hainanenwsisko,EY.ChenetW.Y Chen(prosp)为海南海桑的新名称,而拟海桑S.paracseolarisKo,E.Y.Chen,etW,ChenY.Chen则被归并入sonneratia×gulngaiN.C.Duke. 展开更多
关键词 海桑属 分类学 杂交种 海南海桑 拟海桑 红树林
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基于市盈率修正的非上市公司国有股权定价模型研究 被引量:2
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作者 王平 刘莎 +1 位作者 张竞元 黄文思 《价值工程》 2010年第2期2-4,共3页
外资并购国有企业对我国国有企业改革和资本市场的发展具有重要的推动作用,合理确定国有股的转让价是外资并购中的核心问题,它将直接影响到外资并购的成功与否。基于市盈率修正的非上市公司国有股权定价模型,根据恰当的指标采用德尔菲... 外资并购国有企业对我国国有企业改革和资本市场的发展具有重要的推动作用,合理确定国有股的转让价是外资并购中的核心问题,它将直接影响到外资并购的成功与否。基于市盈率修正的非上市公司国有股权定价模型,根据恰当的指标采用德尔菲法选取上市公司作为参照公司,将非流通股和流通股区别定价,采用加权法确定上市公司合理市盈率,解决了直接利用流通股市盈率估价非流通股存在的市盈率易被高估的问题,完善了传统的股权定价理论,对非上市公司国有股权定价具有很好的指导作用。 展开更多
关键词 外资并购 非上市公司 国有放权是价 市盘率修正
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基于混合跟踪模型的室内步行人体3D运动估计 被引量:3
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作者 于雪松 赵巍 +1 位作者 刘鹏 唐降龙 《自动化学报》 EI CSCD 北大核心 2010年第6期773-784,共12页
针对步行人体3D运动估计过程中的自遮挡问题,提出了基于混合跟踪模型的粒子滤波算法.首先,利用自遮挡状态检测模型,将步行人体运动划分为四种自遮挡状态;其次,根据混合跟踪模型,针对不同的自遮挡状态,算法采用不同的跟踪模型;最后,为了... 针对步行人体3D运动估计过程中的自遮挡问题,提出了基于混合跟踪模型的粒子滤波算法.首先,利用自遮挡状态检测模型,将步行人体运动划分为四种自遮挡状态;其次,根据混合跟踪模型,针对不同的自遮挡状态,算法采用不同的跟踪模型;最后,为了估计遮挡状态下的人体运动,算法提出了基于M–估计的在线训练方法以训练肢体运动相关系数.经过实验分析,算法对处于自遮挡状态下的人体3D运动估计有着良好的效果,人体3D运动的估计精度得到了提高. 展开更多
关键词 混合跟踪模型 步行人体运动 自遮挡状态检测模型 m-估计 肢体运动相关系数
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Description of spectrum and electromagnetic transitions in ^(94)Mo through the proton-neutron interacting boson model
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作者 ChengFu Mu DaLi Zhang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2018年第1期37-43,共7页
We investigated the properties of low-lying states in ^(94)Mo within the framework of the proton-neutron interacting boson model(IBM-2), with special focus on the characteristics of mixed-symmetry states. We calculate... We investigated the properties of low-lying states in ^(94)Mo within the framework of the proton-neutron interacting boson model(IBM-2), with special focus on the characteristics of mixed-symmetry states. We calculated level energies and M1 and E2 transition strengths. The IBM-2 results agree with the available quantitative and qualitative experimental data on ^(94)Mo. The properties of mixed-symmetry states can be well described by IBM-2 given that the energy of the d proton boson is different from that of the neutron boson, especially for the transition of B(M1, 4_2^+→ 4_1^+). 展开更多
关键词 94mo mixed-symmetry states m1 and e2 transition strengths IBm-2
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Evidence for resonant structures in e^+e^-→π^+π^-h_c
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作者 苑长征 《Chinese Physics C》 SCIE CAS CSCD 2014年第4期1-4,共4页
: The cross sections of e+e-→π+π-hc at center-of-mass energies from 3.90 to 4.42 GeV were measured by the BESIII and the CLEO-c experiments. Resonant structures are evident in the e+e-→π+π-hc line shape. Th... : The cross sections of e+e-→π+π-hc at center-of-mass energies from 3.90 to 4.42 GeV were measured by the BESIII and the CLEO-c experiments. Resonant structures are evident in the e+e-→π+π-hc line shape. The fit to the line shape results in a narrow structure at a mass of (4216±18) MeV/c2 and a width of (39±2) MeV, and a possible wide structure of mass (4293±9) MeV/c2 and width (222=k67) MeV. Here, the errors are combined statistical and systematic errors. This may indicate that the Y(4260) state observed in e+e-→π+π-J/ψ has a fine structure in it. 展开更多
关键词 CHARmONIUm chramoniumlike states ee- annihilation eXOTICS hybridS
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