为了进一步提高电能质量评估结果的精细化程度,提出了一种基于灰色关联度分析(Grey Relational Analysis,GRA)、二元语义(Binary Semantics,BS)和逼近理想解排序法(Technique for Order Preference by Similarity to an Ideal Solution,...为了进一步提高电能质量评估结果的精细化程度,提出了一种基于灰色关联度分析(Grey Relational Analysis,GRA)、二元语义(Binary Semantics,BS)和逼近理想解排序法(Technique for Order Preference by Similarity to an Ideal Solution,TOPSIS)的电能质量综合评估方法。首先建立电能质量综合评估指标体系;其次利用G1法确定主观权重,采用指标相关法(Criteria Importance Though Intercrieria Correlation,CITIC)确定客观权重,并引入博弈论优化主客观综合权重系数,得到各项指标的综合权重;然后使用TOPSIS方法计算监测点指标数据与各指标对应的最优、最劣解之间的欧氏距离,并结合灰色关联度计算出相对贴近度,将其作为确定电能质量等级的判据并进行一次评估;最后利用二元语义法对一次评估结果中电能质量等级相同的监测点进行更为精细的二次评估。仿真算例结果验证该方法的有效性和精细性。展开更多
共价键均裂在含能分子的热分解过程中普遍存在,因此极为重要.然而,以往的理论研究通常用键能(ΔH,BDE)估算均裂能垒,因忽略了熵效应,必然造成较大误差.采用对称破缺密度泛函方法(BS-UB3LYP/6-311+G**),对含能分子3-硝基-1,2,4-三唑-5-酮...共价键均裂在含能分子的热分解过程中普遍存在,因此极为重要.然而,以往的理论研究通常用键能(ΔH,BDE)估算均裂能垒,因忽略了熵效应,必然造成较大误差.采用对称破缺密度泛函方法(BS-UB3LYP/6-311+G**),对含能分子3-硝基-1,2,4-三唑-5-酮(NTO)的热分解机理进行了系统研究和梳理,计算了共价键均裂的过渡态及能垒.结果表明,C—NO_(2)键均裂和随后的自由基复合是最优途径,能垒为216.9 k J·mol^(-1)(523 K).随后产生的NO自由基通过多次“复合-均裂”过程促进三唑中间体开环,分解为HNCO,N_(2)O和CO等小分子,它们相互反应又生成NO_(2),N_(2)和CO_(2).这些分解产物与诸多实验观测结果一致.展开更多
In the framework of the heavy quark effective theory, the leading order Isgur-Wise functions relevant to semileptonie decays of the orbitally P-wave excited Bs meson states Bs＊, including the newly found narrow Bs1 ...In the framework of the heavy quark effective theory, the leading order Isgur-Wise functions relevant to semileptonie decays of the orbitally P-wave excited Bs meson states Bs＊, including the newly found narrow Bs1 （5830） andBs2（5840） states, into the （Ds1（2536）, Ds2（2573）） doublet are calculated from QCD sum rules. With these universal form factors, the decay rates and branching ratios are also estimated.展开更多
Structural buildings are subjected to huge cyclic powers during earthquakes. The structural failures during seismic events notably impact a variety of facets of buildings within tolerable levels like sustainable stren...Structural buildings are subjected to huge cyclic powers during earthquakes. The structural failures during seismic events notably impact a variety of facets of buildings within tolerable levels like sustainable strength and stable energy dissipation capability to sustain inter-story drifts and overall structural damages. The major structural elements such as columns, beams and soil shearing capacities are majorly affected during seismic events. Buildings situated in the earthquake prone zone are exposed to most concerns in the structural design. Boreholes are also one of the main factors responsible for seismic waves and soil shearing. Shear strength is a term used in soil mechanics to describe the magnitude of the shear stress that soil can sustain, especially selected BC soil. The shear resistance of soil is a result of friction and interlocking of particles, and possibly cementation or bonding at particle contacts. Soils consist of individual particles that can slide and roll relative to one another. Shear strength of a soil is equal to the maximum value of shear stress that can be mobilized within a soil mass without failure taking place. In many parts of the world to avoid or control these consequences, buildings have been constructed as steel-composite structures. However, in India, buildings are being constructed as RCC framed structures. Here a novel combination of VANE shear footing and BRB method has been introduced. In this article, the effects of boreholes increase seismic bearing capacity of foundation, and load bearing capacity to balance seismic pressure.展开更多
文摘为了进一步提高电能质量评估结果的精细化程度,提出了一种基于灰色关联度分析(Grey Relational Analysis,GRA)、二元语义(Binary Semantics,BS)和逼近理想解排序法(Technique for Order Preference by Similarity to an Ideal Solution,TOPSIS)的电能质量综合评估方法。首先建立电能质量综合评估指标体系;其次利用G1法确定主观权重,采用指标相关法(Criteria Importance Though Intercrieria Correlation,CITIC)确定客观权重,并引入博弈论优化主客观综合权重系数,得到各项指标的综合权重;然后使用TOPSIS方法计算监测点指标数据与各指标对应的最优、最劣解之间的欧氏距离,并结合灰色关联度计算出相对贴近度,将其作为确定电能质量等级的判据并进行一次评估;最后利用二元语义法对一次评估结果中电能质量等级相同的监测点进行更为精细的二次评估。仿真算例结果验证该方法的有效性和精细性。
文摘结合对称性破损(BS)方法,采用不同的密度泛函理论(DFT)对反铁磁性μ-1,3-N3-Ni(II)叠氮配合物[LNi2(N3)](Cl O4)2(L=pyrazolate)的磁特性进行了研究.结果显示,杂化密度泛函理论(HDFT)的计算结果与实验数据非常吻合,能够准确描述配合物的磁特性.磁轨道研究结果表明,配合物表现出较大的单占据轨道能量劈裂(0.93-0.99 e V),显示配合物的单占据轨道去简并化程度较大,且配合物中的2个磁通道(叠氮基、配体pyrazolate)中都分别存在有氮原子之间的p轨道重叠,这些都使得体系表现为反铁磁耦合作用.另外,配合物的磁性与叠氮桥和两金属离子间形成的二面角(τ,Ni-N-N-N-Ni)密切相关,τ从-55.38°逐渐变化到-1.5°的过程中,其反铁磁性逐渐增强,交换耦合常数(Jab)的绝对值逐渐增大,并在-11.95°处达到最大值(Jab=-151.02 cm-1).在此过程中,配合物中叠氮桥及其所连接的2个Ni离子与pyrazolate基配体L-中的2个桥原子N(4)、N(5)形成的七元环共平面性不断增强,即共平面性会诱导增强体系的反铁磁相互作用.
文摘共价键均裂在含能分子的热分解过程中普遍存在,因此极为重要.然而,以往的理论研究通常用键能(ΔH,BDE)估算均裂能垒,因忽略了熵效应,必然造成较大误差.采用对称破缺密度泛函方法(BS-UB3LYP/6-311+G**),对含能分子3-硝基-1,2,4-三唑-5-酮(NTO)的热分解机理进行了系统研究和梳理,计算了共价键均裂的过渡态及能垒.结果表明,C—NO_(2)键均裂和随后的自由基复合是最优途径,能垒为216.9 k J·mol^(-1)(523 K).随后产生的NO自由基通过多次“复合-均裂”过程促进三唑中间体开环,分解为HNCO,N_(2)O和CO等小分子,它们相互反应又生成NO_(2),N_(2)和CO_(2).这些分解产物与诸多实验观测结果一致.
基金Supported by the National Natural Science Foundation of China under Grant No. 10975184
文摘In the framework of the heavy quark effective theory, the leading order Isgur-Wise functions relevant to semileptonie decays of the orbitally P-wave excited Bs meson states Bs＊, including the newly found narrow Bs1 （5830） andBs2（5840） states, into the （Ds1（2536）, Ds2（2573）） doublet are calculated from QCD sum rules. With these universal form factors, the decay rates and branching ratios are also estimated.
文摘Structural buildings are subjected to huge cyclic powers during earthquakes. The structural failures during seismic events notably impact a variety of facets of buildings within tolerable levels like sustainable strength and stable energy dissipation capability to sustain inter-story drifts and overall structural damages. The major structural elements such as columns, beams and soil shearing capacities are majorly affected during seismic events. Buildings situated in the earthquake prone zone are exposed to most concerns in the structural design. Boreholes are also one of the main factors responsible for seismic waves and soil shearing. Shear strength is a term used in soil mechanics to describe the magnitude of the shear stress that soil can sustain, especially selected BC soil. The shear resistance of soil is a result of friction and interlocking of particles, and possibly cementation or bonding at particle contacts. Soils consist of individual particles that can slide and roll relative to one another. Shear strength of a soil is equal to the maximum value of shear stress that can be mobilized within a soil mass without failure taking place. In many parts of the world to avoid or control these consequences, buildings have been constructed as steel-composite structures. However, in India, buildings are being constructed as RCC framed structures. Here a novel combination of VANE shear footing and BRB method has been introduced. In this article, the effects of boreholes increase seismic bearing capacity of foundation, and load bearing capacity to balance seismic pressure.
