Results 31 to 40 of about 2,331,158 (156)
, 2006 洛河是黄河的一条重要支流。本文采用洛河氵状头水文站1965~2003年共计39年的实测径流资料,依据线性平稳随机模型的理论建立了一阶自回归模型;运用季节性随机模型的理论方法建立洛河氵状头站月径流量典型解集模型。经实用性检验,模拟序列与实测序列各项估计参数吻合良好,符合精度要求 ...
徐利岗, 周宏飞
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Resource Substitution: Local Governments' Issue Attention and Policy Reinvention
Policy Studies Journal, EarlyView.ABSTRACT Research on policy reinvention, where a government modifies rather than replicates policy innovations introduced by other governments, has progressed significantly, but how it is influenced by the government's issue attention has not been thoroughly examined.
Yingxin Zhang, Yixue Yao, Kaifeng Yang
wiley +1 more source
, 2004 引言在爆炸成形工艺技术发展的现阶段,模型试验是确定工艺条件和工艺参数(如所需药量)的一个主要方法。因此,如何选定模型试验方案,如何整理和归纳试验数据以及如何根据模型试验结果,确定实物生产的工艺条件和参数等就成为需要研究和解决的问题。换言之,需要研究和解决模型律问题。在这篇报告里讨论,当毛料为薄板或薄壳的时候,爆炸成形的模型律,提出我们对这一问题的见解和认为需要进一步探讨的问题。为明确起见,我们把所讨论的对象规定为:药包具有一定的几何形状,而且除药包尺寸和毛料的厚度外,毛料的其他尺寸,药包的悬挂位置 ...
郑哲敏
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Regional News, Regional Bias? Evidence From Media Discourses and Welfare Decisions in Germany
Policy Studies Journal, EarlyView.ABSTRACT How do media representations of immigrants shape their treatment by street‐level bureaucrats? Despite a uniform federal legal framework, decision‐making varies substantially across local welfare offices. Though prior research links national news reporting and policy implementation, little is known about how regional variation in news reporting
Stefanie Rueß
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, 1989 建立移动式机器人的环境模型，是近年来智能机器人研究领域中的一个重要课题。本文论述的主要内容是在超声建模的中间层次－几何模型的基础上，运用超图理论为指导，通过对环境空间的几何、拓朴性质的研究，在环境建模的高层次上建立适用于移动式机器人路径规划和导航任务的抽象模型－道路模型，以及将这一模型具体应用于移动式机器人路径规划的研究工作。方中提出了对几何模型予处理中的物体边缘的检出及标记算法，以及边缘扩展的赋值边图匹配法；在最大交迭区、基本凸多边区及道路宽度等模型信息的获取过程中，本文主要从建模理论的完整性 ...
侯秋枫
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Risk, Hazards &Crisis in Public Policy, Volume 17, Issue 3, September 2026.ABSTRACT Disasters and crises disrupt lives and test the capacities of governments and organizations. While their immediate aftermath is often marked by uncertainty and disruption, recurrent patterns in how individuals are affected give rise to foreseeable hardships.
Michel L. A. Dückers
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, 2015 本实用新型提供了一种三维模型打印系统。该三维模型打印系统包括：工控机；驱动装置，所述驱动装置与所述工控机电连接，所述工控机控制所述驱动装置运动；以及喷嘴阵列，所述喷嘴阵列包括n行×m列个的喷嘴，其中，n≥1，m≥1，第n行中的第m个所述喷嘴的轴线和第n+1行中的第m或m+1个所述喷嘴的轴线之间存在距离，所述工控机控制所述驱动装置带动所述喷嘴开启或者关闭，解决了打印速度与打印精度不能兼容的技术难题 ...
张远明, 张文武
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Intangible drivers of tolerance shape human–elephant coexistence in Southwest China
People and Nature, Volume 8, Issue 8, Page 2763-2780, August 2026.Abstract Southwest China is home to a small but rapidly expanding population of Asian elephants (Elephas maximus), whose growth has intensified conflicts with people living in shared landscapes. These conflicts result in substantial economic losses and occasional human casualties. This coexistence paradox—where conservation success leads to significant
Xiaoyu Yu +4 more
wiley +1 more source
, 2010 本发明公开了一种高速列车动模型试验系统，该试验系统包括列车动模型单元和空气炮驱动单元，列车动模型单元包括列车模型及其导轨，列车模型可在空气炮驱动单元驱动下沿其导轨滑动；空气炮驱动单元包括高压气体发生装置、炮管、运动部件，运动部件安装在炮管内，高压气体发生装置直接或通过管路与炮管后端相接，并通过向炮管内输入高压气体驱动运动部件运动，并通过运动部件带用炮管外的列车模型一同运动。利用本发明试验系统不仅可以进行隧道空气动力学研究 ...
李斌, 李进平, 陈宏
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World Water Policy, Volume 12, Issue 3, August 2026.ABSTRACT Bengaluru, a primary metropolitan centre in India, is currently grappling with the dual crises of urban flooding and severe groundwater depletion. These challenges are driven by rapid urbanization, which has seen built‐up areas increase from 42% to 86% over two decades, resulting in a dramatic loss of vegetation and wetlands.
S. Biswas, S. V. B. Patel, B. Maheshwari
wiley +1 more source