Results 61 to 70 of about 622,398 (259)

一种微流控塑料芯片注射成型模具

open access: yes, 2003
一种微流控塑料芯片注射成型模具,其特征在于:模具主要由底板、模板、定型板、封闭板、立柱、螺母A组合而成;模板上表面具有芯片通道形状的凸起;定型板中部具有芯片形状的通孔A;封闭板中部具有开口M4~M12的螺孔,芯片进出口位置具有芯片进出口形状的通孔B;底板、模板、定型板、封闭板由下至上依次叠合并夹紧,立柱插入封闭板上的通孔B中,螺母A螺合于封闭板的螺孔中。用本实用新型模具成型的芯片形状尺寸均一,不需要后续的处理 ...
林炳承, 戴忠鹏, 罗勇
core  

Changes in the transformative potential of action proposals in Finnish Red Lists from 1986 to 2019

open access: yesConservation Biology, EarlyView.
Abstract Red lists provide critical knowledge regarding biodiversity decline, especially in Finland, where broad assessments have been made regularly since the 1980s. They deliver information on the threat status of species and ecosystems, propose actions to guide conservation policy, and have the potential to spur transformative change.
Anni Arponen   +4 more
wiley   +1 more source

雁型断裂的分形模型和能量耗散

open access: yes, 1994
现场和实验室观察表明;在断裂区内的雁型裂纹具有一个Riedel几何结构。本文应用剪切裂纹位错堆积(Pile-up)模型;描述了雁型裂纹形成的拉破坏机理;建立了雁型裂纹的分形模型来模拟Riedel几何结构。根据这个模型;可以直接量测出现场和实验中出现的雁型裂纹的分形维数。在此基础上;应用分形损伤演化模型;推导出了雁型裂纹的能量耗散 ...
谢和平
core  

Uncovering correlates of decline and critical refuges for a threatened terrestrial mammal

open access: yesConservation Biology, EarlyView.
Abstract Globally, the geographic ranges of numerous species are contracting. Identifying spatiotemporal patterns of threat impact can illuminate why species decline in some parts of their range but persist in others. We developed a correlative approach to identify species’ response thresholds and locate ecological refuge areas associated with ...
Natalya M. Maitz   +5 more
wiley   +1 more source

洛河径流典型解集模型研究

open access: yes, 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
core  

Institutional lessons from the Nordic management model

open access: yesConservation Biology, EarlyView.
Abstract To improve wildlife management outcomes, in terms of reaching management goals and increasing legitimacy, Nordic countries have developed institutional systems involving stakeholders that aim for a more inclusive and participatory model.
Jens Nilsson   +2 more
wiley   +1 more source

腰椎间盘突出症实验动物模型的应用与展望

open access: yesZhongguo shiyan zhenduanxue
在腰椎间盘突出症(lumbar disc herniation,LDH)领域,实验动物模型的建立至关重要。本文综合评估了不同类型的LDH动物模型。腰椎间盘退行性病变模型模拟了LDH的早期发病机制,LDH模型则可分为压迫性模型和非压迫性模型。总体而言,不同实验动物模型在模拟LDH病理过程中各具特点,为疾病机制研究和药物开发提供了重要的参考借鉴。未来研究可进一步优化不同模型,以更好地模拟临床情况,促进相关研究进一步发展。
曹卓妍   +4 more
doaj  

VPN资源管理中Hose模型的研究

open access: yesGuangtongxin yanjiu, 2005
文章首先介绍了虚拟专用网(VPN)中提供服务质量(QoS)的两种模型(管道模型和软管模型)的基本概念,然后通过对两种模型的比较,给出了软管(Hose)模型的优点以及实现方式,最后给出了在Hose模型下最小生成树的求解的基本理论和实现算法。
张宏伟, 何岩
doaj  

爆炸成形模型律

open access: yes, 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
core  

Integrating fossil data in ecological niche models to improve predictions of future habitat of Caribbean corals

open access: yesConservation Biology, EarlyView.
Abstract Ecological niche models (ENMs) are used to assess the abiotic preferences of species by linking their occurrences to the environmental conditions in which they live. We developed a fossil‐informed ENM framework that integrates mid‐Holocene and modern occurrences to test niche stability and reconstruct abiotic niche characteristics for four ...
Claire. M. Williams   +3 more
wiley   +1 more source

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