Results 101 to 110 of about 39,766 (300)
Precise asymptotics in the complete moment convergence of NA sequence(负相伴随机变量序列矩完全收敛的精确渐近性)
Zhejiang Daxue xuebao. Lixue ban, 2005 假设{X,Xn; n≥1}为平稳的负相伴随机变量序列.对其矩完全收敛的精确渐近性进行讨论.令EX1=0，E|X1 ...
JIANGYe(蒋), ZHANGLi-xin(张立新)
doaj +1 more source
Investigation on Martensitic Transformation and Shape Memory Effect at High Temperature in Co-V-X (X: Si, Al) Alloys [PDF]
, 2017 形状记忆合金是一种具有形状记忆效应和超弹性的智能材料，用作驱动元件时，具有响应频率高、可回复应变大等优点。但是在传统的形状记忆合金中，马氏体相变温度较低，难以达到一些高温环境下特殊应用的要求。由此，研究者们开发出了一些具有较高马氏体相变温度的形状记忆合金，即高温形状记忆合金。然而，在已有的高温形状记忆合金中，各自存在着一些主要的问题：一是在较高的温度下，马氏体的热稳定性较差；二是在多晶合金中，由金属间化合物转变而来的马氏体脆性较大，影响到高温形状记忆合金的延展性 ...
蒋恒星
core
Policy Studies Journal, EarlyView.Abstract Defined by threat, urgency, and uncertainty, crises produce opportunities for government leaders to exploit and create meaning around their policy decisions in such unstable circumstances. In narrating their preferred policy solutions, one of the tools governments can use is relying on evidence‐based information.
Laura Mastroianni, Stefania Profeti
wiley +1 more source
新化合物——Sr<sub>2</sub>CdWO<sub>6</sub>的相变和晶体结构 [PDF]
, 1990 正民 傅
openalex +1 more source
Networking strategies for coordinating interdependent policy issues: A motif approach
Policy Studies Journal, EarlyView.Abstract Complex societal challenges, such as climate change and environmental degradation, are encumbered by numerous interdependences across different policy issues. Coordination of interdependent policy issues is thus critical. However, coordination challenges persist, partly because coordinating interdependent policy issues among actors often ...
Johanna Hedlund +2 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan为揭示偏心竖向荷载作用下薄壁箱梁的畸变，基于能量变分原理和箱梁各板件的静力平衡分析，给出优化后箱梁畸变研究的3种方法。推导出各方法研究梯形截面箱梁畸变解析计算式的普遍形式，得出相应的四阶畸变控制微分方程。对各畸变研究方法采用典型数值算例进行验证，研究结果表明：优化后的各畸变研究方法计算的畸变翘曲正应力的值同文献数值相差很小，各方法之间误差最大不超过5.39%，方法2和方法3计算结果误差很小可忽略；各方法计算矩形截面箱梁的畸变扇性坐标值都相等，梯形截面箱梁的则不同 ...
王兆南, 张元海
doaj +2 more sources
Transition metal compounds and alloys: A first-principles investigation [PDF]
, 2015 含过渡金属的化合物与合金在数据存储、光催化和能量存储与转换等领域有重要的应用，主要得益于其特定的电子结构、力学性能等性质。本论文利用基于密度泛函理论的第一性原理计算方法，选取特定的研究体系，系统地探索了过渡金属化合物与合金的电子结构（第三章）、内部原子扩散（第四章）、力学性能（第五章）以及压力与温度对其性质的影响（第六章）。 为了研究缺陷和掺杂对过渡金属氧化物电子结构的调制，我们以SrZrO3为研究对象，首先研究了内部含有有序氧空位和部分无序氧空位体系的电子结构。计算结果表明 ...
郭忠路
core
Institutions, in time: Designing feedback pathways for shared infrastructure transitions
Policy Studies Journal, EarlyView.Abstract Electric utilities, challenged by a rapidly unfolding energy transition, use many informal institutions to bridge across technologies and sectors. Little is known, however, about how electric utility systems and other polycentric systems' institutions‐in‐use vary and evolve over time.
Matthew Grimley +6 more
wiley +1 more source