空间下弦式液压滑模在小孤山水电站调压井的应用

文中论述了在张掖小孤山电站洞压井的竖井井筒部位采用空间下弦式液压滑模进行衬砌施工的过程,该技术的应用减少了钢材的消耗量,降低了爬升系统的运行难度,整体抗变形能力加强,保证了工程质量.     

欠秩3-UPU并联角台机构工作空间分析

针对欠秩3—UPU并联角台机构的结构特点,首先找出了该机构的几何约束,在此基础上建立了该机构移动副两端虎克铰平行或垂直布置时的位置反解方程。然后利用该机构的几何约束条件,进一步建立了该机构在两种情况下的工作空间的求解方程,为该机构的应用奠定了一定的基础。     

谈工程图学中空间思维的培养

文章分析了学生学习工程制图前的思维习惯，分析了现行教学方法中培养学生空间思维能力的方法和环节的欠缺之处，并提出了加强培养学生空间思维的方法。     

TEMPORAL AND SPATIAL DISCRETIZATION ON QUASI-3-D GROUNDWATER FINITE ELEMENT MODELLING TO AVOID SPURIOUS OSCILLATION

In this article, the finite element solution of quasi-three-dimensional (quasi-3-D) groundwater flow was mathematically analyzed. The research shows that the spurious oscillation solution to the Finite Element Model (FEM) is the results choosing the small time step ?t or the large element size L and using the non-diagonal storage matrix. The mechanism for this phenomenon is explained by the negative weighting factor of implicit part in the discretized equations. To avoid spurious oscillation solution, the criteria on the selection of ?t and L for quasi-3-D groundwater flow simulations were identified. An application example of quasi-3-D groundwater flow simulation was presented to verify the criteria. The results indicate that temporal discretization scale has significant impact on the spurious oscillations in the finite-element solutions, and the spurious oscillations can be avoided in solving practical quasi-3-D groundwater flow problems if the criteria are satisfied.     

Integrated solid-state nanopore devices for third generation DNA sequencing

Third generation DNA sequencing relies on monitoring the ionic current blockage during the DNA molecule’s threading through a nanoscale pore.It is still really tough to attain the single base discrimination on a DNA strand by merely analyzing the ionic current due to speedy DNA translocation and low spatial resolution.More integrated configurations are pursued to present versatile comparative dissimilarities of the four bases by enhancing the spatial resolution within a DNA molecule translocation event,such as transverse tunneling current,local potential change,and capacitance oriented voltage resonance.In this mini review,the insight is provided into the status quo on several functionalized techniques and methodologies for DNA sequencing and furthermore concluding remark and outlook are presented.     

GIS线状缓冲区生成算法研究

缓冲区分析是地理信息系统重要的空间分析功能之一．地理信息系统中的缓冲区生成分点、线、面3种,线状目标缓冲区的生成是点、线、面3种基本空间要素缓冲区生成的关键和基础,文中就线状目标缓冲区的两种生成算法进行了严密的数学推导,并通过编程实现取得了较好的效果．     

MCNP模拟钴-60辐照装置空间剂量场

为模拟辐照室中辐照工位外的周围空间剂量场分布,采用蒙特卡罗粒子输运程序MCNP建立钴-60辐照装置模型。以单板源架中心点为坐标原点的笛卡尔坐标系,考虑钴-60源的γ射线非自吸收和自吸收两种情况,研究坐标轴方向上每隔10 cm间距的空气平面的剂量率和坐标轴上剂量率的变化规律。结果表明,辐照室中辐照产品占满辐照工位的情况下,周围空间剂量场空气面剂量率整体较小;单板源架中心坐标轴上的剂量率变化规律更符合二项式拟合函数。在钴-60源γ射线自吸收情况下,单板源架端面坐标轴附近的空气面剂量率明显偏小,且随着空气面远离单板源架,空气面上的高剂量率区域向两侧移动;在钴-60源γ射线非自吸收情况下,单板源架端面处的空气面高剂量区域始终位于坐标轴附近。MCNP理论模拟计算分析对于利用钴-60辐照装置辐照工位外的周围空间剂量场具有重要的实际指导意义。     

Emotional modulation of cognitive control: Approach–withdrawal states double-dissociate spatial from verbal two-back task performance.

Emotional states might selectively modulate components of cognitive control. To test this hypothesis, the author randomly assigned 152 undergraduates (equal numbers of men and women) to watch short videos intended to induce emotional states (approach, neutral, or withdrawal). Each video was followed by a computerized 2-back working memory task (spatial or verbal, equated for difficulty and appearance). Spatial 2-back performance was enhanced by a withdrawal state and impaired by an approach state; the opposite pattern held for verbal performance. The double dissociation held more strongly for participants who made more errors than average across conditions. The results suggest that approach–withdrawal states can have selective influences on components of cognitive control, possibly on a hemispheric basis. They support and extend several frameworks for conceptualizing emotion–cognition interactions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

普通住宅户型分析

介绍了户型中不同功能空间的布局设计，从动区、静区以及细节设计三方面分析了普通住宅户型的设计方法，以提高设计水平，满足居住者的生活质量要求。     

上海进一步发展的城市空间结构探索

从构筑上海与都市圈相融合的空间结构理念出发,阐述上海大都市圈内城市等级构成及分布;探讨区域交通、产业、生态、文化、旅游走廊的贯通及"指掌形"空间的形成;提出上海与周边地区协调发展的布局形态设想及市域范围内城镇空间系列建议.